Lens manufacturing method

Abstract

To provide a manufacturing method of lens, capable of manufacturing a spectacle lens with good yield and high reliability from a polarizable curved laminate.SOLUTION: The manufacturing method of lens includes: a first step of obtaining a curve-shaped polarizable curved laminate from a polarizable laminate; a second step of bringing the polarizable curved laminate into close contact with a mold; and a third step of forming a resin layer on the polarizable curved laminate. The polarizable laminate is curved such that radius of curvature RB1, and radius of curvature RB2 of curved concave surfaces of the mold and the radius of curvature R1, and radius of curvature R2 of curved convex surfaces of the polarizable curved laminate satisfy either one of the relational expressions (A), (B) and do not satisfy the relational expression (C) in the first step. 0.70≤RB1 / R1≤1.00 and 1.00≤RB2 / R2≤1.40...(A), 1.00≤RB1 / R1≤1.40 and 0.70≤RB2 / R2≤1.00...(B), and 0.95<RB1 / R1<1.06 and 0.95<RB2 / R2<1.06...(C).SELECTED DRAWING: Figure 3

Description

[Technical field]

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

[0002] 2. Description of the Related Art There has been proposed a lens for glasses that includes a polarizing laminate (resin substrate) configured such that both sides of a polarizing film are covered with covering layers mainly made of polycarbonate-based resin, polyamide-based resin, or the like.

[0003] This lens (spectacle lens) is manufactured, for example, by punching a polarizing laminate having a flat overall shape into a predetermined shape such as a circle in a plan view with protective films attached to both sides of the polarizing laminate. Then, the polarizing laminate is subjected to a heat bending process under heating to form a polarizing curved laminate curved by heat bending. Then, after peeling off the protective film from the polarizing curved laminate, the polarizing curved laminate is adsorbed to a mold having a curved recess such that the recess of the mold and the protruding portion of the polarizing curved laminate come into contact with each other, and a resin layer mainly made of a resin material such as a polycarbonate-based resin or a polyamide-based resin is formed on the concave surface of the polarizing curved laminate by 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 typically has a radius of curvature of its convex portion that is set to be 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 adhered 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 the insert injection molding method 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, the polarizing curved laminate cannot be attached to the mold with sufficient adhesiveness due to slight misalignment of the installation position of the polarizing curved laminate relative to the mold or the environment in which the polarizing curved laminate is attached, etc., and this causes 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] JP 2009-294445 A Summary of the Invention [Problem to be solved by the invention]

[0007] An object of the present invention is to provide a method for producing a lens that can produce a highly reliable eyeglass lens with a high yield from a polarizing curved laminate. [Means for solving the problem]

[0008] Such objectives are as follows: 6 This is achieved by the present invention described in (1) A first step of obtaining a polarizing curved laminate, the polarizing laminate having a flat overall shape including 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, by bending the polarizing laminate into a curved shape such that one surface of the polarizing laminate forms a curved concave surface and the other surface of the polarizing laminate forms a curved convex surface; Radius of curvature in one direction R B1 [mm], radius of curvature R in a direction perpendicular to the one direction B2a second step of closely contacting the polarizing curved laminate with a mold having a curved concave surface of 1 mm in diameter, with the other surface side of the polarizing curved laminate that is the curved convex surface facing the mold; and a third step of forming a resin layer bonded to the polarizing curved laminate on the one surface side of the polarizing curved laminate, the one surface side being the curved concave surface, while maintaining the polarizing curved laminate in intimate contact with the mold, The radius of curvature in the one direction on the other surface of the polarizing curved laminate, which is the curved convex surface, is R 1 [mm], and the radius of curvature in the orthogonal direction is R 2 When expressed in [mm], A method for manufacturing a lens, characterized in that in the first step, the polarizing laminate is curved to obtain the polarizing curved laminate so that either one of the following relational formula (A) or the following relational formula (B) is satisfied, but the following relational formula (C) is not satisfied. 0.70≦R B1 / R 1 ≦1.00, And 1.00≦R B2 / R 2 ≦1.40 … (A) 1.00≦R B1 / R 1 ≦1.40, And 0.70≦R B2 / R 2 ≦1.00 … (B) 0.95 <R B1 / R 1 <1.06, and 0.95 <R B2 / R 2 <1.06 … (C)

[0009] (2) In the first step, The above The coefficient (A) is satisfied, and furthermore, 1.07 <R 1 / R 2 < 1.68, or The above-mentioned relational expression (B) is satisfied, and further, <R 1 / R 2The method for producing a lens according to the above (1), further comprising curving the polarizing laminate so as to satisfy the relationship:

[0010] (3) In the first step, 3. The method for producing a lens according to claim 2, further comprising curving the polarizing laminate so as to satisfy the following relational expression (1):

number

[0011] (4) The radius of curvature R B1 , the radius of curvature R B2 The method for manufacturing a lens according to any one of (1) to (3) above, each of which is independently 58 mm or more and 523 mm or less.

[0012] (5) The method for manufacturing a lens according to any one of (1) to (4) above, wherein the one direction of the polarizing curved laminate is MD, and the orthogonal direction of the polarizing curved laminate is TD.

[0013] (6) The method for manufacturing a lens according to any one of (1) to (5) above, wherein the first resin layer and the second resin layer are each independently made of a polycarbonate-based resin or a polyamide-based resin as a main material. Effect of the Invention

[0015] According to the present invention, when a lens for glasses is manufactured using a polarizing curved laminate that has been curved by thermal bending, i.e., when a resin layer is formed on the curved concave surface of the polarizing curved laminate, it is possible to appropriately 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, lenses with excellent reliability can be manufactured with a good yield. [Brief description of the drawings]

[0016] [Figure 1]FIG. 1 is a perspective view of an embodiment of sunglasses with lenses having a polarizing curved laminate. [Diagram 2] FIG. 2 is a vertical cross-sectional view showing an embodiment of a polarizing curved laminate included in a lens. [Diagram 3] 1A to 1C are schematic diagrams illustrating a method for manufacturing a lens having a polarizing curved laminate. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0017] DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The lens manufacturing method of the present invention will be described in detail below with reference to preferred embodiments shown in the accompanying drawings.

[0018] The method for producing the lens of the present invention includes a first step of curving a polarizing laminate 15 having a flat overall shape, the polarizing laminate 15 including 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, into a curved shape such that one side of the polarizing laminate 15 constitutes a curved concave surface and the other side of the polarizing laminate constitutes a curved convex surface to obtain a polarizing curved laminate 10; B1 [mm], radius of curvature R in a direction perpendicular to the one direction B2 a second step of closely contacting the polarizing curved laminate 10 with a mold 40 having a curved concave surface of 10 mm in diameter, with the other surface of the polarizing curved laminate 10 that is the curved convex surface facing the mold 40; and a third step of forming a resin layer 35 bonded to the polarizing curved laminate 10 on the one surface of the polarizing curved laminate 10 that is the curved concave surface while maintaining the state in which the polarizing curved laminate 10 is closely contacted with the mold 40, thereby obtaining a lens 30. 1 [mm], and the radius of curvature in the orthogonal direction is R 2 The present invention is characterized in that, in the first step, the polarizing laminate 15 is curved to obtain a polarizing curved laminate 10 so that, when the length (mm) of the polarizing laminate 15 is 1 or 2, the following relational formula (A) or (B) is satisfied, but the following relational formula (C) is not satisfied.

[0019] 0.70≦RB1 / R 1 ≦1.00, And 1.00≦R B2 / R 2 ≦1.40 … (A) 1.00≦R B1 / R 1 ≦1.40, And 0.70≦R B2 / R 2 ≦1.00 … (B) 0.95 <R B1 / R 1 <1.06, and 0.95 <R B2 / R 2 <1.06 … (C)

[0020] According to such a lens manufacturing method, when a lens 30 for glasses is manufactured using the polarizing curved laminate 10 that has been curved by thermal bending, i.e., when a resin layer 35 is formed on the curved concave surface of the polarizing curved laminate 10, it is possible to appropriately suppress or prevent the polarizing curved laminate 10 from falling off from the mold 40 used to form the resin layer 35. In other words, the polarizing curved laminate 10 can be adsorbed to the mold 40 with excellent adhesiveness. Therefore, a lens 30 with excellent reliability can be manufactured with a good yield.

[0021] A lens 30 including a polarizing curved laminate 10 manufactured by applying the lens manufacturing method of the present invention is used, for example, as a lens included in sunglasses 100, which is a type of eyeglasses. Therefore, in the following, first, sunglasses 100 including this lens 30 will be described before describing the lens manufacturing method of the present invention.

[0022] <Sunglasses> Fig. 1 is a perspective view showing an embodiment of sunglasses equipped with lenses having a polarizing curved laminate, and Fig. 2 is a longitudinal cross-sectional view showing an embodiment of a polarizing curved laminate equipped with the lenses. In Fig. 1, when the sunglasses are worn on the head of a user, the surface of the lens facing the user's eyes is called the back surface, and the opposite surface is called the front surface. In Fig. 2, for convenience of explanation, the upper side of Fig. 2 is called "upper" and the lower side is called "lower".

[0023] As shown in FIG. 1, the sunglasses 100 include a frame 20 and a lens 30 (a lens for glasses).

[0024] In this specification, the term "lens" includes both those having a light-collecting function and those not having a light-collecting function.

[0025] The frame 20 is fitted to the head of a user so as to position the lenses 30 adjacent to and in front of the user's eyes.

[0026] The frame 20 has a rim portion 21, a bridge portion 22, a temple portion 23, and a nose pad portion 24.

[0027] The rim portions 21 are ring-shaped, one for each of the right and left eyes, and have lenses 30 attached to their insides. This allows the user to view external information through the lenses 30.

[0028] Furthermore, 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.

[0029] The temple portion 23 is shaped like a temple and is connected to the edge of each rim portion 21 on the opposite side to the position where the bridge portion 22 is connected. The temple portion 23 is hung on the user's ear when wearing the glasses on the user's head.

[0030] The nose pads 24 are provided on the edges of the rims 21 that correspond to the nose of the user when the sunglasses 100 are worn on the head of the user, and come into contact with the nose of the user, forming a shape that corresponds to the contact portion of the nose of the user at this time. This allows the sunglasses 100 to be stably maintained when worn.

[0031] The materials constituting the respective parts 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 figure, so long as it can be worn on the head of the user.

[0032] The lens 30 is a spectacle lens that is attached to each of the rim portions 21. The lens 30 is a light-transmitting, plate-shaped member that is curved outward, and includes a resin layer 35 and a polarizing curved laminate 10, and is manufactured by applying the lens manufacturing method of the present invention described below.

[0033] The resin layer 35 has optical transparency and is located on the rear side of the lens. When the lens 30 is provided with a light collecting function, the resin layer 35 has the light collecting function.

[0034] The material for the resin layer 35 is not particularly limited as long as it is a resin material having optical transparency, and examples thereof include various curable resins such as various thermoplastic resins, thermosetting resins, and photocurable resins, and one or a combination of two or more of these can be used.

[0035] Examples of the resin material 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 the resin layer 35 include polyether ketone (PEEK), polyetherimide, polyacetal (POM), polyphenylene oxide, polysulfone, polyethersulfone, polyphenylene sulfide, polyarylate, aromatic polyester (liquid crystal polymer), polytetrafluoroethylene, polyvinylidene fluoride, other fluorine-based resins, epoxy resin, phenol resin, urea resin, melamine resin, silicone resin, polyurethane, etc., or copolymers, blends, polymer alloys, etc. that mainly contain these, but among these, it is preferable that the resin layer 35 is the same type or the same as the resin material that constitutes the first resin layer 11 of the polarizing curved laminate 10 described below. This can improve the adhesion between the resin layer 35 and the polarizing curved laminate 10.

[0036] The thickness of the resin layer 35 is not particularly limited, and is preferably, for example, 0.5 mm to 5.0 mm, and more preferably 1.0 mm to 3.0 mm, which allows the lens 30 to have both a relatively high strength and a lightweight structure.

[0037] 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 corresponding to the shape, thereby imparting polarization to the sunglasses 100. As a result, the sunglasses 100 exhibit the function of polarized sunglasses having polarization. This polarizing curved laminate 10 is composed of the polarizing curved laminate of the present invention, but a detailed description thereof will be given later.

[0038] The polarizing curved laminate 10 is obtained by bending a polarizing laminate 15 having an overall flat shape into a curved shape in the manufacturing method of the lens 30 described below. As shown in FIG. 2, the polarizing curved laminate 10 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, 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.

[0039] (Polarizing Film 13) The polarizing film 13 has a function of extracting linearly polarized light having a polarization plane in a predetermined direction from incident light (unpolarized natural light). As a result, the light passing through the polarizing curved laminate 10 (polarizing laminate 15) becomes polarized.

[0040] The polarization degree of the polarizing film 13 is not particularly limited, but is preferably, for example, from 50% to 100%, and more preferably from 80% to 100%. The visible light transmittance of the polarizing film 13 is not particularly limited, but is preferably, for example, from 10% to 80%, and more preferably from 20% to 50%.

[0041] The material for forming such polarizing film 13 is not particularly limited as long as it has the above-mentioned function, and examples thereof include a polymer film formed of polyvinyl alcohol (PVA), partially formalized polyvinyl alcohol, polyethylene vinyl alcohol, polyvinyl butyral, polycarbonate, ethylene-vinyl acetate copolymer partially saponified product, etc., which is dyed with a dichroic substance such as iodine or a dichroic dye and uniaxially stretched, a polyene-based oriented film such as a dehydrated product of polyvinyl alcohol or a dehydrochlorinated product of polyvinyl chloride, etc.

[0042] Among these, the polarizing film 13 is preferably a polymer film mainly made of polyvinyl alcohol (PVA), which is dyed with iodine or a dichroic dye and uniaxially stretched. Polyvinyl alcohol (PVA) is a material that is excellent in transparency, heat resistance, affinity with the dyeing agent iodine or a dichroic dye, and orientation during stretching. Therefore, the polarizing film 13 mainly made of PVA has excellent heat resistance and polarizing ability.

[0043] 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.

[0044] The thickness of the polarizing film 13 is not particularly limited, and is preferably, for example, from 5 μm to 60 μm, and more preferably from 10 μm to 40 μm.

[0045] (First resin layer 11 and second resin layer 12) As shown in FIG. 2, the first resin layer 11 and the second resin layer 12 are provided on the lower surface (one surface) and upper surface (the other surface) of the polarizing film 13, respectively, and thereby function as protective layers for protecting the polarizing film 13.

[0046] The first resin layer 11 and the second resin layer 12 are not particularly limited, but may be mainly made of resin materials such as polyamide resin, polycarbonate resin, and cellulose resin such as triacetyl cellulose, and may be used alone or in combination of two or more of these. Among them, it is preferable to use polyamide resin or polycarbonate resin as the main material.

[0047] Polycarbonate-based resins are rich in transparency (light transmissivity) and mechanical strength such as rigidity, and therefore can improve the transparency and impact resistance of the polarizing curved laminate 10. Furthermore, polycarbonate-based resins have a specific gravity of about 1.2, and are classified as light among resin materials, which can reduce the weight of the polarizing curved laminate 10. Furthermore, polyamide-based resins can improve the chemical resistance, stress resistance, and the like, in addition to the transparency and impact resistance.

[0048] 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 be made to exhibit excellent impact resistance. Moreover, semi-aromatic polyamide is a material with a high elastic modulus. Therefore, the polarizing curved laminate 10 can be made to have excellent resistance to stress such as bending.

[0049] 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).

[0050] [ka] (However, R in formula (1B) 1 and R 2 one of which is a divalent aromatic substituent and the other is a divalent aliphatic substituent, and n is an integer of 2 or greater.

[0051] The polyamide may be a copolymer (random copolymer, block copolymer, etc.) containing two or more kinds of monomers of at least one of dicarboxylic acid and diamine.

[0052] In addition, R in the above formula (1B) 1 , R 2Of these, the aromatic substituent is preferably one represented by the following formula (2B).

[0053] [ka] (In formula (2B), l and m each independently represent an integer of 0 or more and 2 or less.)

[0054] This can more suitably 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.

[0055] R in the above formula (1B) 1 , R 2 Of these, the aliphatic substituent is preferably one having 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 .

[0056] 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 control by stretching can be more easily performed.

[0057] An alicyclic polyamide has an alicyclic chemical structure in its molecule, and may have an alicyclic chemical structure in its main chain structure or may have an alicyclic chemical structure in its side chain structure.

[0058] Examples of the 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).

[0059] [ka] (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.

[0060] The polycarbonate resin is not particularly limited and various types can be used, but among them, aromatic polycarbonate resins are preferable. Aromatic polycarbonate resins have aromatic rings in their main chains, which can improve the strength of the polarizing curved laminate 10.

[0061] 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.

[0062] Examples of bisphenols include bisphenol A and bisphenol (modified bisphenol) which is the source of the repeating unit of polycarbonate represented by the following formula (1A).

[0063] [ka] (In formula (1A), X is an alkyl group having 1 to 18 carbon atoms, an aromatic group, or a cyclic aliphatic group; Ra and Rb are each independently an alkyl group having 1 to 12 carbon atoms; m and n are each an integer of 0 to 4; and p is the number of repeating units.)

[0064] Specific examples of bisphenols that are the source of the repeating units of the polycarbonate represented by the 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 any of these may be used alone or in combination of two or more.

[0065] In particular, it is preferable that the polycarbonate resin is mainly composed of a bisphenol-type polycarbonate resin having a skeleton derived from bisphenol. By using such a bisphenol-type polycarbonate resin, the polarizing curved laminate 10 exhibits even greater strength.

[0066] 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 more and 190°C or less, more preferably 105°C or more and 155°C or less. This makes it relatively easy to form the polarizing curved laminate 10 by heat bending the polarizing laminate 15 in step [3] of the manufacturing method of the lens 30 described later. Furthermore, when retardation is to be expressed in the first resin layer 11 and the second resin layer 12, stretching for expressing this retardation can be suitably performed. Furthermore, the durability and reliability of the polarizing curved laminate 10 can be improved.

[0067] 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 may include, for example, a resin material other than the main material, a colorant such as a dye, a filler, an alignment aid, a stabilizer (such as a heat stabilizer, an ultraviolet absorber, and an antioxidant), a plasticizer, a colorant, a flame retardant, an antistatic agent, and a viscosity adjuster.

[0068] 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.

[0069] The first resin layer 11 and the second resin layer 12 may be made of the same material or different materials.

[0070] 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.

[0071] As a result, the second resin layer 12 is easily deformed in a direction in which the curvature of curvature becomes smaller due to thermal shrinkage, but the first resin layer 11 is less likely to deform due to thermal shrinkage. Therefore, as shown in FIG. 2, by applying the polarizing curved laminate 10 provided in the lens 30, it is used in a curved state, and in this case, it is preferable to make 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, since the second resin layer 12 has a relatively high thermal shrinkage rate, it is relatively easy to thermally deform, but in the polarizing curved laminate 10, the first resin layer 11 exerts a function of suppressing the 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, it is possible to appropriately suppress or prevent the shape of the lens 30 itself from being deformed due to the thermal deformation of the polarizing curved laminate 10.

[0072] The retardation of the first resin layer 11 is preferably 0 nm or more and 500 nm or less, 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, 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. Therefore, the polarization performance of the polarizing curved laminate 10 can be sufficiently improved.

[0073] 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 thicknesses, and further the stretching ratios.

[0074] The average thickness of the first resin layer 11 and the second resin layer 12 is not particularly limited, and is, for example, preferably 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.

[0075] 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.

[0076] Moreover, it is 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.

[0077] (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 to bond the polarizing film 13 to the second resin layer 12. This can improve the durability of the polarizing curved laminate 10.

[0078] 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, silicone adhesives, etc. 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 conformability to changes in shape.

[0079] The thickness of the adhesive layers 16, 17 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, so that the adhesive layers 16, 17 can reliably provide their functions.

[0080] Depending on the configurations of the first resin layer 11, the second resin layer 12 and the polarizing film 13, the formation of the adhesive layers 16 and 17 may be omitted.

[0081] The polarizing curved laminate 10 preferably has a total thickness of 0.1 mm or more and 2 mm or less.

[0082] In the sunglasses 100 having such a configuration, as described above, the lens 30 may or may not have a light-collecting function.

[0083] Furthermore, as described above, the sunglasses 100 may have the frame 20, or may have a frameless configuration from the standpoint of fashionability, lightweightness, and the like.

[0084] Furthermore, in this embodiment, the glasses of the present invention are applied to sunglasses 100, but are not limited to this, and the glasses of the present invention may be, for example, prescription glasses, fashion glasses, goggles that protect the eyes from wind, rain, dust, chemicals, etc.

[0085] In the sunglasses 100 configured as described above, the lenses 30 provided in the sunglasses 100 are manufactured by the manufacturing method of the lens 30 of the present invention, as described below.

[0086] <Lens manufacturing method> 3 is a schematic diagram for explaining 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 "upper" and the lower side as "lower".

[0087] 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 that includes a first resin layer 11, a polarizing film 13, and a second resin layer 12 that are laminated in this order to have a flat overall shape. That is, a polarizing laminate 15 is prepared that 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 to obtain a multilayer laminate 150 in which protective films 50 are attached to both sides of the polarizing laminate 15 (see FIG. 1(a)).

[0088] [2] Next, as shown in FIG. 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 its thickness direction, so that the multilayer laminate 150 has a circular shape in a plan view.

[0089] 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.

[0090] 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 about 110° C. or more and 170° C. or less, more preferably about 140° C. or more and 160° C. or less, taking into consideration the melting or softening temperatures of resin layers 11, 12, in which polarizing laminate 15 comprises resin layers 11, 12. Setting the heating temperature within this range prevents alteration or deterioration of polarizing laminate 15, and allows polarizing laminate 15 to be brought into a softened or molten state and reliably heat-bent to form polarizing curved laminate 10 having a curved shape.

[0091] The above steps [1] to [3] constitute a first step of obtaining a polarizing curved laminate by curving the polarizing laminate 15.

[0092] [4] Next, the protective film 50 is peeled off from the thermally bent polarizing curved laminate 10. Thereafter, 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 B2The second resin layer 12 (the other side) of the polarizing curved laminate 10, which is the curved convex surface, is placed against the mold 40 having a curved concave surface measuring 12 mm in diameter, and the second resin layer 12 is brought into contact with the curved concave surface of the mold 40, thereby bringing the polarizing curved laminate 10 into close contact (adsorbed) with the mold 40 (second step).

[0093] [5] Next, while maintaining the polarizing curved laminate 10 in intimate contact with the mold 40, a resin layer 35 bonded to the polarizing curved laminate 10 is formed on the side of the first resin layer 11 (one surface) that is the curved concave surface of the polarizing curved laminate 10 (third step). This produces a lens 30 that includes the thermally bent polarizing curved laminate 10 and the resin layer 35.

[0094] The formation of the resin layer 35 on the first resin layer 11 side of this polarizing curved laminate 10 is carried out, for example, by using an insert injection molding method to injection mold the resin layer 35 made of a resin material onto the curved concave surface of the polarizing curved laminate 10.

[0095] Among the insert injection molding methods, the injection compression molding method is preferably used. The injection compression molding method is a method in which the resin material for forming the resin layer 35 is injected into the mold 40 at low pressure, and then the mold 40 is closed at high pressure to apply a compressive force to the resin material, so that the resin layer 35 as a molded body and the lens 30 are less likely to suffer from molding distortion or optical anisotropy due to the local orientation of the resin molecules during molding. In addition, by controlling the mold compression force applied uniformly to the resin material, the resin material can be cooled at a constant specific volume, so that the resin layer 35 with high dimensional accuracy can be obtained.

[0096] In the above-described lens manufacturing method, in the present invention, when the polarizing curved laminate 15 is curved to form the polarizing curved laminate 10 in the step [3], the degree of curvature is set to a radius of curvature in the one direction on the curved convex surface on the other surface side of the polarizing curved laminate 10, which is R 1 [mm], and the radius of curvature in the orthogonal direction is R 2When expressed in [mm], it is set so as to satisfy either the following relational expression (A) or the following relational expression (B) but not to satisfy the following relational expression (C).

[0097] 0.70≦R B1 / R 1 ≦1.00, And 1.00≦R B2 / R 2 ≦1.40 … (A) 1.00≦R B1 / R 1 ≦1.40, And 0.70≦R B2 / R 2 ≦1.00 … (B) 0.95 <R B1 / R 1 <1.06, and 0.95 <R B2 / R 2 <1.06 … (C)

[0098] Here, in forming the resin layer 35 on the polarizing curved laminate 10 in the step [5] of the above-mentioned lens manufacturing method, it becomes necessary to adhere the curved polarizing curved laminate 10 to the curved concave surface of the mold 40 so that the curved convex surface of the polarizing curved laminate 10 corresponds to the curved concave surface of the mold 40 without causing the polarizing curved laminate 10 to fall off. That is, it becomes necessary to form the resin layer 35 on the curved concave surface of the polarizing curved laminate 10 in the step [5] while maintaining the close contact of the polarizing curved laminate 10 with the mold 40 in the step [4].

[0099] 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 to the curved concave surface of mold 40 with high positional accuracy.

[0100] Furthermore, when forming the resin layer 35, if the mold 40 is positioned so that the opening of its curved concave surface is aligned along the vertical direction, as shown in Figure 3(d), i.e., if the mold 40 is positioned upright in the vertical direction, it can be said that 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.

[0101] In response to such a demand, in the step [3], in which the flat polarizing laminate 15 is subjected to a thermal bending process under heating to form the polarizing curved laminate 10 having a curved shape, the curvature of the curved convex surface of the polarizing curved laminate 10 is usually 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 is a problem that the polarizing curved laminate 10 frequently falls off from the mold 40 because the polarizing curved laminate 10 cannot be attached to the mold 40 with sufficient adhesiveness due to a 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.

[0102] As a result of thorough investigation into these problems, the inventors have discovered that the frequency with which the polarizing curved laminate 10 falls off from the mold 40 can be reduced by intentionally misaligning the curvature of the curved convex surface of the polarizing curved laminate 10 with the curvature of the curved concave surface of the mold 40 rather than making it match.

[0103] The inventor then conducted further investigation into the magnitude of this misalignment, and as a result, found that when the misalignment of the polarizing curved laminate 10 in one direction relative to the mold 40 and the misalignment in the orthogonal direction are both maintained at a certain level or above so as not to satisfy the following relational formula (C), by setting one of the misalignment of the polarizing curved laminate 10 in one direction relative to the mold 40 to be large and the other to be small so as to satisfy either the following relational formula (A) or the following relational formula (B), the polarizing curved laminate 10 can be adhered to the mold 40 with excellent adhesion and the frequency of the polarizing curved laminate 10 falling off from the mold 40 can be accurately suppressed or prevented, and thus reliable lenses 30 can be manufactured with good yield, thereby completing the present invention.

[0104] 0.70≦R B1 / R 1 ≦1.00, And 1.00≦R B2 / R 2 ≦1.40 … (A) 1.00≦R B1 / R 1 ≦1.40, And 0.70≦R B2 / R 2 ≦1.00 … (B) 0.95 <R B1 / R 1 <1.06, and 0.95 <R B2 / R 2 <1.06 … (C)

[0105] The curvature of the curved concave surface of the mold 40 is set in accordance with the lens 30 to be molded, and is usually set to 1 to 9 curves in both the one direction and the orthogonal direction, and the radius of curvature R B1 , radius of curvature R B2 In terms of the polarization direction of the lens 30, it is preferable that the one direction is MD (flow direction) and the direction perpendicular to the one direction is TD (direction perpendicular to the flow direction).

[0106] When forming such a lens 30, the radius of curvature R is set so as to satisfy either the above relational expression (A) or the above relational expression (B) and not to satisfy the above relational expression (C). B1 and the radius of curvature R B2 and the radius of curvature R 1 and the radius of curvature R 2 However, it is preferable to satisfy either one of the following relational expressions (a1) and (b1), and more preferably either one of the following relational expressions (a2) and (b2), while maintaining the above relational expression (C) not being satisfied. This makes it possible to more significantly reduce the frequency with which the polarizing curved laminate 10 falls off from the mold 40.

[0107] 0.75≦R B1 / R 1 ≦0.95, And 1.03≦R B2 / R 2 ≦1.30 … (a1) 1.03≦R B1 / R 1 ≦1.30, And 0.75≦R B2 / R 2 ≦0.95 … (b1) 0.76≦R B1 / R 1 ≦0.93, And 1.06≦R B2 / R 2 ≦1.29 … (a2) 1.06≦R B1 / R 1 ≦1.29, And 0.76≦R B2 / R 2 ≦0.93 … (b2)

[0108] Furthermore, the radius of curvature R 1 and the radius of curvature R 2 It is preferable that at least one of the following two relational expressions is satisfied:

[0109] Specifically, on the one hand, R 1 / R 2 is further set to 1.07 when the above-mentioned relational formula (A) is satisfied. <R 1 / R 2 <1.68 is preferable, and 1.26 <R 1 / R 2 <1.67. In addition, when the above-mentioned relational expression (B) is satisfied, it is more preferable that the above-mentioned relational expression (B) is satisfied. <R 1 / R 2 <0.93 is preferable, and 0.60 <R 1 / R 2 It is more preferable to satisfy <0.79.

[0110] On the other hand, it is preferable that the following relational formula (1) is satisfied, and it is more preferable that the following relational formula (1') is satisfied.

[0111]

number

[0112] radius of curvature R B1 and the radius of curvature R B2 and the radius of curvature R 1 and the radius of curvature R 2 By setting the relational expression within the above range, it is possible to more significantly reduce the frequency with which the polarizing curved laminate 10 falls off from the mold 40. As a result, it is possible to manufacture the highly reliable lenses 30 with an even higher yield.

[0113] Although the lens manufacturing method of the present invention has been described above, the present invention is not limited to this.

[0114] For example, in the method for manufacturing the lens of the present invention, one or more steps can be added for any purpose. EXAMPLES

[0115] The present invention will be described in detail below based on examples, but the present invention is not limited thereto. 1. Fabrication of polarizing curved laminates Example 1 First, a polyvinyl alcohol-based film was dyed with an aqueous solution containing a dye while being stretched in a water tank, and then treated with boric acid. The treated polyvinyl alcohol-based film was then washed with water and dried. This resulted in a polarizing film 13 having a thickness of 35 μm.

[0116] Meanwhile, a polyamide resin (alicyclic polyamide, Grilamid TR90 manufactured by EMS) was used as the first resin material, and a sheet-like first resin layer 11 having a thickness of 0.2 mm was obtained by extrusion molding using a vented single screw extruder.

[0117] 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.

[0118] Next, a two-component moisture-curing polyurethane adhesive (base: Mitsui Chemicals, Inc.'s "Takelac A-520", hardener: Mitsui Chemicals, Inc.'s "Takenate A-50") was applied as a first adhesive to a thickness of 20 μm after drying using a bar coater on one side of the first resin layer 11. Also, a two-component moisture-curing polyurethane adhesive (base: Mitsui Chemicals, Inc.'s "Takelac A-520", hardener: Mitsui Chemicals, Inc.'s "Takenate A-50") was applied as a second adhesive to a thickness of 20 μm after drying using a bar coater on one side of the second resin layer 12.

[0119] Next, the first resin layer 11 and the second resin layer 12 on which the first adhesive and the second adhesive were applied, respectively, were placed in an oven and heated until the solvent in the first adhesive and the second adhesive was dried. This resulted in a first laminate in which the adhesive layer 16 (first adhesive layer) was laminated on one surface of the first resin layer 11, and a second laminate in which the adhesive layer 17 (second adhesive layer) was laminated on one surface of the second resin layer 12.

[0120] Thereafter, the first laminate was laminated on the polarizing film 13 so that the adhesive layer 16 was in contact with one surface of the polarizing film 13, and the second laminate was laminated on the polarizing film 13 so that the adhesive layer 17 was in contact with the other surface of the polarizing film 13, thereby obtaining a polarizing laminate 15. At this time, the first laminate, polarizing film 13, and second laminate were each pressed together using a rubber roll of a laminator, so that the total thickness of the polarizing laminate 15 was 0.75 mm.

[0121] Then, protective films 50 made of polyolefin were laminated by a lamination method on both sides of such a 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.

[0122] Next, the polarizing laminate 15 was punched out to a diameter of 8 cm, and then subjected to a thermal bending process while suctioning at 150° C. for 10 minutes using a Rema molding machine (vacuum molding machine) (CR-32 type). 1 is 80.5 mm, and the radius of curvature R in TD (the orthogonal direction perpendicular to one direction) 2 The polarizing curved laminate 10 of Example 1 was obtained, having a thickness of 87.2 mm.

[0123] (Examples 2 to 9, Example 11, Comparative Examples 1 to 3) 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 a heat bending process while being sucked using a REMA molding machine (vacuum molding machine) (CR-32 type), whereby the radius of curvature R shown in Table 1 was obtained. 1 and the radius of curvature R 2 The polarizing curved laminates 10 of Examples 2 to 9, Example 11, and Comparative Examples 1 to 3 were obtained in the same manner as in Example 1, except that the polarizing curved laminate 10 had a size of

[0124] Example 10 As 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, a polycarbonate resin (Mitsubishi Engineering Plastics Corporation, "Iupilon E-2000") was used instead of a polyamide resin (EMS Corporation, "Grilamid TR90"), and the polarizing laminate 15 was subjected to a hot bending process while being sucked using a Rema molding machine (vacuum molding machine) (CR-32 type), thereby obtaining a radius of curvature R as shown in Table 1. 1 and the radius of curvature R 2 The polarizing curved laminate 10 of Example 10 was obtained in the same manner as in Example 1, except that the polarizing curved laminate 10 had a size of 10 mm.

[0125] 2. Evaluation (Deletion 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.

[0126] That is, for the polarizing curved laminates 10 of the respective examples and comparative examples, the radius of curvature R B1 [mm] and radius of curvature R B2 The specimen was attached to a mold 40 having a curved concave surface of 1 mm in diameter, and the presence or absence of the specimen falling off from the mold 40 after 5 seconds was confirmed.

[0127] Then, the polarizing curved laminates 10 of each Example and Comparative Example were checked for the presence or absence of falling off, and 100 pieces were tested for each Example and Comparative Example. The results of the evaluation of the falling off property of this polarizing curved laminate 10 are shown in Table 1.

[0128] [Table 1]

[0129] As shown in Table 1, each example satisfies either the following relational formula (A) or the following relational formula (B), but does not satisfy the following relational formula (C), and it has been revealed that the polarizing curved laminate 10 can be prevented from falling off from the mold 40.

[0130] In contrast, in each comparative example, either neither the following relational formula (A) nor the following relational formula (B) was satisfied, or the following relational formula (C) was satisfied, and as a result, the polarizing curved laminate 10 frequently fell off from the mold 40. 0.70≦R B1 / R 1 ≦1.00, And 1.00≦R B2 / R 2 ≦1.40 … (A) 1.00≦R B1 / R 1 ≦1.40, And 0.70≦R B2 / R 2 ≦1.00 … (B) 0.95 <R B1 / R 1 <1.06, and 0.95 <R B2 / R 2 <1.06 … (C) [Explanation of symbols]

[0131] 10. Polarizing curved laminate 11 First resin layer 12 Second resin layer 13 Polarizing film 15 Polarizing laminate 16 First adhesive layer 17 Second adhesive layer 20 Frames 21 Rim 22 Bridge section 23 Temple Section 24 Nose pad section 30 Lenses 35 Resin layer 40 Mold 50 Protective Film 100 Sunglasses 150 Multilayer laminate 200 Curved multi-layer laminate

Claims

1. a first step of obtaining a polarizing curved laminate by bending a polarizing laminate having a flat overall shape, the polarizing laminate including 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, into a curved shape such that one surface of the polarizing laminate constitutes a curved concave surface and the other surface of the polarizing laminate constitutes a curved convex surface; 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 closely contacting the polarizing curved laminate with a mold having a curved concave surface of 1 mm in diameter, with the other surface of the polarizing curved laminate, which is the curved convex surface, facing the mold; and a third step of forming a resin layer bonded to the polarizing curved laminate on the one surface side of the polarizing curved laminate, the one surface side being the curved concave surface, while maintaining the polarizing curved laminate in intimate contact with the mold, The radius of curvature in the one direction on the other surface of the polarizing curved laminate, which is the curved convex surface, is R １ [mm], and the radius of curvature in the perpendicular direction is R ２ When expressed in [mm], A method for manufacturing a lens, characterized in that in the first step, the polarizing laminate is curved to obtain the polarizing curved laminate so as to satisfy either the following relational formula (A) or the following relational formula (B) but not to satisfy the following relational formula (C). 0.70≦R Ｂ１ / R １ ≦1.00、 And 1.00≦R Ｂ２ / R ２ ≦1.40 … (A) 1.00≦R Ｂ１ / R １ ≦1.40、 And 0.70≦R Ｂ２ / R ２ ≦1.00 … (B) 0.95<R Ｂ１ / R １ <1.06、 And 0.95<R Ｂ２ / R ２ <1.06 … (C)

2. In the first step, The above-mentioned relational expression (A) is satisfied, and further, 1.07<R １ / R ２ < 1.68, or The above-mentioned relational expression (B) is satisfied, and further, 0.59<R １ / R ２ The method for manufacturing a lens according to claim 1 , wherein the polarizing laminate is curved so as to satisfy the relationship: φ<0.

93.

3. In the first step, The method for producing a lens according to claim 2 , further comprising curving the polarizing laminate so as to satisfy the following relational expression (1): [0010]

4. The radius of curvature R Ｂ１ , the radius of curvature R Ｂ２ The method for manufacturing a lens according to claim 1 , wherein each of the above is independently 58 mm or more and 523 mm or less.

5. The method of claim 1 , wherein the one direction of the polarizing curved laminate is MD and the orthogonal direction of the polarizing curved laminate is TD.

6. The method for manufacturing a lens according to claim 1 , wherein the first resin layer and the second resin layer are each independently made of a polycarbonate-based resin or a polyamide-based resin as a main material.

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