Lens manufacturing method

Abstract

The present invention addresses the problem of providing a lens manufacturing method with which it is possible to: suppress wraparound of a film-forming composition on a rear surface of a lens base material; form a film on the entire surface of the lens base material; and obtain a film having excellent smoothness. This lens manufacturing method is for coating a film-forming composition through spin-coating on a lens base material that does not have a perfectly circular shape in plan view, to form a film and manufacture a lens. During the spin-coating, when defining, as a proximity position, a position closest to a center position of the major axis of the lens base material on an outer edge of the lens base material in plan view of the lens base material, and defining, as a distance Z, a distance from the center position of the major axis to the proximity position, a discharge amount of the film-forming composition and a first position and a second position satisfy prescribed requirements when discharging the film-forming composition while a nozzle for discharging the film-forming composition from the tip is linearly moving from the first position to the center position of the major axis of the lens base material or to the second position located across the center position of the major axis from the first position through the center position of the major axis, while rotating the lens base material around the center position of the major axis as the rotation center.

Description

Lens manufacturing method

[0001] The present disclosure relates to a method for manufacturing a lens.

[0002] Patent Document 1 discloses a method for manufacturing a heat mode type optical information recording medium having a recording layer on a substrate on which information can be recorded by irradiation with laser light, in which a solution for forming the recording layer is applied to the substrate while the substrate is being rotated, and the rotation speed of the substrate is increased when the solution is applied to the inner peripheral side of the substrate.

[0003] Japanese Patent Application Laid-Open No. 2000-155994

[0004] The present disclosure relates to a lens manufacturing method that applies a film-forming composition to a lens substrate that is not perfectly circular in plan view by spin coating to form a film and manufacture a lens, wherein, when, in plan view of the lens substrate, the position on the outer edge of the lens substrate that is closest to the center position of the major axis of the lens substrate is defined as a proximity position, and the distance from the center position of the major axis to the proximity position is defined as distance Z, the lens substrate is rotated in the spin coating method around the center position of the major axis as the center of rotation, and a nozzle that ejects the film-forming composition from its tip is moved linearly from a first position to the center position of the major axis of the lens substrate, or through the center position of the major axis to a second position that is located between the first position and the center position of the major axis, and the film-forming composition is ejected while the nozzle is moved linearly from a first position to the center position of the major axis of the lens substrate, or through the center position of the major axis to a second position that is located between the first position and the center position of the major axis, and the method satisfies any of requirements 1 to 3 described below.

[0005] 1A and 1B are schematic cross-sectional views showing a method for manufacturing a lens of the present disclosure, a diagram showing positional relationships in the method for manufacturing a lens of the present disclosure, and a cross-sectional view of one embodiment of a lens obtained by the method for manufacturing a lens of the present disclosure.

[0006] The present disclosure will be described in detail below. According to the lens manufacturing method of the present disclosure (hereinafter also referred to as the "present manufacturing method"), it is possible to prevent the film-forming composition from spreading to the back surface of the lens substrate, allowing a film to be formed over the entire surface of the lens substrate, and the resulting film also has excellent smoothness. Hereinafter, the property of easily forming a film over the entire surface of the lens substrate will also be referred to as "full-surface coatability." The following explanation of the constituent elements may be based on representative embodiments of the present disclosure, but the present disclosure is not limited to such embodiments.

[0007] In this specification, a numerical range expressed using "to" means a range that includes the numerical values ​​written before and after "to" as the lower and upper limits. Furthermore, in this specification, when two or more types of a component are present, the "content" of that component means the total content of those two or more components. In this specification, in a numerical range described in stages, the upper or lower limit value described in a certain numerical range may be replaced with the upper or lower limit value of another numerical range described in stages. Furthermore, in a numerical range described in this specification, the upper or lower limit value described in a certain numerical range may be replaced with a value shown in the Examples. In this specification, a combination of two or more preferred embodiments is a more preferred embodiment.

[0008] As used herein, the "solids" of a composition refers to the components that form a layer formed using the composition. When the composition contains a solvent (e.g., an organic solvent and water), this refers to all components excluding the solvent. Furthermore, liquid components that form a layer using the composition are also considered to be solids. As used herein, angular relationships (e.g., "perpendicular," "parallel," etc.) are intended to encompass the range of error acceptable in the technical field to which the present disclosure pertains. Specifically, this refers to a range of less than ±10° from the strict angle, and the error from the strict angle is preferably within ±5° or less, and more preferably within ±3° or less. The bonding direction of divalent groups described herein is not limited unless otherwise specified. For example, when Y is -COO- in a compound represented by the formula "X-Y-Z," Y may be either -CO-O- or -O-CO-. Furthermore, the compound may be either "X-CO-O-Z" or "X-O-CO-Z." In this specification, the term "(meth)acrylic" is a concept that encompasses either or both of acrylic and methacrylic, and the terms "(meth)acrylate" and "(meth)acryloyl" have the same meaning.

[0009] <Lens Manufacturing Method> The lens manufacturing method of the present disclosure is a method of applying a film-forming composition to a lens substrate that is not perfectly round in plan view by spin coating to form a film on the lens substrate. Spin coating is generally performed by placing the lens substrate on a spin coater equipped with a base that can fix and rotate the substrate, and then, while the lens substrate is rotating, ejecting and supplying the film-forming composition from a nozzle onto the surface of the substrate. This allows the film-forming composition to be applied to the entire surface of the substrate by centrifugal force, forming a film.

[0010] The type of film formed by the method of the present disclosure is not particularly limited, but preferred examples include a primer film and a hard coat film. For example, by using a primer layer-forming composition as the film-forming composition, a primer layer can be formed on the lens substrate. Furthermore, by using a hard coat layer-forming composition as the film-forming composition, a hard coat layer can be formed on the lens substrate. The lens substrate, the spin coating method, and the film-forming composition will be described in detail below.

[0011] [Lens Substrate] The lens substrate used in this manufacturing method is a lens substrate that is not perfectly circular in plan view. "Not perfectly circular in plan view" means that the plan view of the lens when viewed from the optical axis direction of the lens (hereinafter also referred to as "lens plan view") is not perfectly circular. A lens substrate that is not perfectly circular in plan view has a major axis and a minor axis. In this disclosure, the major axis refers to the line connecting two parallel lines that are tangent to the outer periphery of the lens substrate in the lens plan view, and two points of contact with the outer periphery of the lens substrate, selected so that the distance between the two lines is the greatest. Note that, when multiple major axes can be defined, the line that provides the smallest value for distance Z' / distance Z, described below, is the major axis. In this disclosure, the minor axis refers to the line connecting two parallel lines that are tangent to the outer periphery of the lens substrate, and two points of contact with the outer periphery of the lens substrate, selected so that the distance between the two lines is the smallest. It is preferable that the major axis and minor axis are perpendicular to each other. Specifically, the acute angle formed by the major axis and the minor axis is preferably 80 to 90°, more preferably 85 to 90°, and even more preferably 87 to 90°. It is also preferable that the minor axis passes through the center position of the major axis. The center positions of the major axis and the minor axis may or may not coincide with each other, but it is preferable that the center positions of the major axis and the minor axis approximately coincide with each other. Specifically, the value of (distance from the center position of the minor axis to the center position of the major axis) / (length of the major axis) is preferably 0.4 or less, more preferably 0.2 or less. The lower limit is 0 or more, and 0 is preferable.

[0012] In a plan view of the lens (in other words, in a plan view of the lens substrate), the position on the outer edge of the lens substrate closest to the center position of the major axis is defined as proximity position Z, and the distance from the center position of the major axis to proximity position Z is defined as distance Z. Among the intersections of a line passing through the center position of the major axis and proximity position Z with the outer edge of the lens substrate, a position other than proximity position Z is defined as position Z', and the distance from the center position of the major axis to position Z' is defined as distance Z'. The value of distance Z' / distance Z is preferably 1.2 or less, more preferably 1.1 or less, and even more preferably 1.05 or less. The lower limit is 1.0 or more. Note that position Z' and proximity position Z are located on either side of the center position of the major axis, and are both located on the outer edge of the lens substrate. In other words, the line connecting position Z' and proximity position Z passes through the center position of the major axis. It is also preferable that the major axis is perpendicular to the line passing through the center position of the major axis and proximity position Z. Specifically, the acute angle formed by the major axis and the line passing through the center position of the major axis and the proximity position Z is preferably 80 to 90°, more preferably 85 to 90°, and even more preferably 87 to 90°. It is also preferable that the line connecting position Z' and the proximity position Z is the minor axis described above.

[0013] Specific examples of the shape of the lens substrate when viewed in plan include ellipse, oval, oval, rectangular, and polygonal, with ellipse being preferred. The aspect ratio (ratio of the major axis to the minor axis) of the lens substrate is preferably 1.5 or less, more preferably 1.4 or less, and even more preferably 1.2 or less. The lower limit is greater than 1.0. The length of the major axis of the lens substrate is not particularly limited, but is often 30 to 80 mm, preferably 40 to 80 mm, and more preferably 40 to 70 mm.

[0014] The thickness of the lens substrate is not particularly limited, but from the viewpoint of ease of handling, it is often about 1 to 30 mm. If the lens has a thickness distribution, it is preferable that the center thickness falls within the above range. The shape of the surface of the lens substrate on which the film-forming composition is formed by spin coating (the surface to be coated) may be flat, convex, or concave, and is often convex. When the surface of the lens substrate to be coated has a convex or concave shape, its radius of curvature is preferably 50 to 2500 mm, more preferably 100 to 1000 mm.

[0015] The refractive index of the lens substrate is not particularly limited, but is often 1.50 or more, preferably 1.60 to 1.80, and more preferably 1.60 to 1.74.

[0016] The type of lens substrate used in this manufacturing method is not particularly limited, but is preferably a lens for spectacles. When the lens is for spectacles, examples include a finished lens in which both the convex and concave surfaces are optically finished and molded to match the desired power, a semi-finished lens in which only the convex surface is finished as an optical surface (spherical, rotationally symmetric aspherical, progressive surface, etc.), and a semi-finished lens in which the concave surface is processed and polished to match the wearer's prescription.

[0017] (Configuration of Lens Substrate) The material of the lens substrate is not particularly limited, and examples thereof include glass lenses and plastic lenses, with plastic lenses being preferred. Examples of glass lenses include inorganic glass lenses. The type of plastic (so-called resin) contained in the plastic lens is not particularly limited, and examples thereof include (meth)acrylic acid ester resin, thiourethane resin, allyl resin, episulfide resin, polycarbonate resin, urethane resin, polyester resin, polystyrene resin, polyethersulfone resin, poly4-methylpentene-1 resin, and diethylene glycol bisallyl carbonate resin (CR-39). Of these, thiourethane resin, episulfide resin, and diethylene glycol bisallyl carbonate resin are preferably used. The thiourethane resin is obtained from a polyisocyanate compound and a polythiol compound. As the polyisocyanate compound, it is preferable to use at least one selected from m-xylylene diisocyanate, a mixture of 2,5-bis(isocyanatomethyl)-bicyclo[2,2,1]heptane and 2,6-bis(isocyanatomethyl)-bicyclo[2,2,1]-heptane, isophorone diisocyanate, hexamethylene diisocyanate, and tolylene diisocyanate. As the polythiol compound, it is preferable to use at least one selected from pentaerythritol tetrakis(3-mercaptopropionate), 1,2-bis[(2-mercaptoethyl)thio]-3-mercaptopropane, and a mixture of 5,7-dimercaptomethyl-1,11-dimercapto-3,6,9-trithiaundecane, 4,7-dimercaptomethyl-1,11-dimercapto-3,6,9-trithiaundecane, and 4,8-dimercaptomethyl-1,11-dimercapto-3,6,9-trithiaundecane. The episulfide resin is obtained by ring-opening polymerization of a monomer having an episulfide group (also referred to as an epithio group) or a mixed monomer containing this monomer. As the monomer having an episulfide group, it is preferable to use at least one selected from bis(2,3-epithiopropyl) sulfide and bis(2,3-epithiopropyl) disulfide.

[0018] The lens substrate may be either transparent or opaque, and preferably has translucency. The lens may also be colored.

[0019] The lens substrate may contain additives such as bluing agents, light stabilizers, UV absorbers, and antioxidants.

[0020] The lens substrate may include layers other than lenses such as plastic lenses and glass lenses. For example, the lens substrate may be a substrate in which another layer is formed on the surface of a plastic lens. Specifically, for example, when a hard coat layer is formed using the present manufacturing method, a primer layer may be included as another layer. Details of the primer layer that may be included as another layer will be described later.

[0021] [Spin ​​Coating Method] As described above, in this manufacturing method, a coating of the film-forming composition is applied to a lens substrate by spin coating. The center of rotation of the lens substrate in the spin coating method is the central position of the major axis of the lens substrate. In this manufacturing method, when discharging the film-forming composition, the nozzle moves linearly from a first position to the central position of the major axis (a position away from the central position of the major axis by 0% of the distance Z) or through the central position of the major axis to a second position located between the first position and the central position of the major axis. The second position is located between the first position and the central position of the major axis; that is, the first position, the central position of the major axis, and the second position are located in this order on a line passing through the central position of the major axis of the lens substrate.

[0022] The present production method satisfies any one of the following requirements 1 to 3, and preferably satisfies requirement 1 or requirement 2 in terms of achieving better effects of the present invention. Requirement 1: The amount of film-forming composition discharged per unit area of ​​the lens substrate in plan view is 0.00100 g / mm ２ 0.00130g / mm or more ２The first position is located at a distance of 83 to 97% of the distance Z from the center position of the major axis, and the second position is located at a distance of more than 0% but not more than 55% of the distance Z from the center position of the major axis. Requirement 2 The amount of film-forming composition discharged per unit area in a plan view of the lens substrate is 0.00080 g / mm ２ 0.00100g / mm or more ２ The first position is located at a distance of 91 to 97% of the distance Z from the center position of the major axis, and the second position is located at a distance of more than 0% but not more than 55% of the distance Z from the center position of the major axis. Requirement 3: The discharge amount of the film-forming composition per unit area in a plan view of the lens substrate is 0.00060 g / mm ２ 0.00080g / mm or more ２ The first position is located at a distance of 93 to 97% of the distance Z from the center position of the major axis, and the second position is located at a distance of more than 0% and not more than 45% of the distance Z from the center position of the major axis.

[0023] (Requirement 1) In Requirement 1, the amount of film-forming composition discharged per unit area of ​​the lens substrate in a plan view is 0.00100 g / m ２ 0.00130g / m or more ２ or less, and ２ 0.00120g / m or more ２ The amount of the film-forming composition discharged per unit area in plan view of the lens substrate is preferably the amount (g) of the film-forming composition discharged from the start of discharge to the end of discharge, multiplied by the area (mm ２ ) and the same applies to the following requirements 2 and 3.

[0024] The first position in requirement 1 is located at a position 83 to 97% of the distance Z from the center position of the major axis. That is, the first position is located between a position 83% of the distance Z from the center position of the major axis and a position 97% of the distance Z from the center position of the major axis. For example, if the distance Z of the lens substrate is 20 mm, the first position is located at a position 16.6 to 19.4 mm from the center position of the major axis. In terms of better overall coatability, the first position in requirement 1 is preferably located at a position 87 to 97% of the distance Z from the center position of the major axis, and more preferably at a position 89 to 97% of the distance Z.

[0025] The second position in requirement 1 is located at a distance from the center position of the major axis that is more than 0% and not more than 55% of the distance Z. For example, if the distance Z of the lens substrate is 20 mm, the second position is located at a distance from the center position of the major axis that is more than 0 mm and not more than 11.0 mm. In terms of superior smoothness, the second position in requirement 1 is preferably located at a distance from the center position of the major axis that is more than 0% and not more than 45% of the distance Z, and more preferably located at a distance from the center position of the major axis that is more than 0% and not more than 35% of the distance Z.

[0026] (Requirement 2) In Requirement 2, the amount of the film-forming composition discharged per unit area in plan view of the lens substrate is 0.00080 g / m ２ 0.00100g / m or more ２ less than 0.00085 g / m ２ 0.00100g / m or more ２ Less than is preferred.

[0027] The first position in requirement 2 is located at a distance of 91 to 97% of the distance Z from the center position of the major axis.

[0028] The second position in requirement 2 is located at a distance from the center position of the major axis that is more than 0% and not more than 55% of the distance Z. In terms of more excellent smoothness, the second position in requirement 2 is preferably located at a distance from the center position of the major axis that is more than 0% and not more than 45% of the distance Z, and more preferably located at a distance from the center position of the major axis that is more than 0% and not more than 35% of the distance Z.

[0029] (Requirement 3) In Requirement 3, the amount of the film-forming composition discharged per unit area in plan view of the lens substrate is 0.00060 g / m ２ 0.00080g / m or more ２ less than 0.00070 g / m ２ 0.00080g / m or more ２ Less than is preferred.

[0030] The first position in requirement 3 is located at a position away from the center position of the major axis by 93 to 97% of the distance Z. In terms of better overall coating properties, the first position in requirement 3 is preferably located at a position away from the center position of the major axis by 95 to 97% of the distance Z.

[0031] The second position in requirement 3 is located at a distance from the center position of the major axis that is more than 0% and not more than 45% of the distance Z. In terms of better smoothness, the second position in requirement 3 is preferably located at a distance from the center position of the major axis that is more than 0% and not more than 35% of the distance Z.

[0032] The method for manufacturing a lens according to the present disclosure will be described below in accordance with the embodiment shown in Figures 1 and 2. Figure 1 is a schematic cross-sectional view of a main part of the spin coating method according to the embodiment of the present disclosure, and Figure 2 is a diagram showing the positional relationship of the spin coating method according to the embodiment of the present disclosure from the direction of the white arrow in Figure 1, and corresponds to a plan view when viewed from the optical axis direction of the lens.

[0033] As shown in FIG. 1 , while the lens substrate 10 is rotating, the nozzle 20 located at a first position begins to discharge the film-forming composition. In FIG. 1 , the dashed line indicates the rotation axis of the lens substrate 10, which passes through the center of the major axis of the lens substrate 10. Note that FIG. 1 shows an embodiment in which the surface of the lens substrate 10 facing the nozzle 20 is convex and the opposite surface is concave. However, the shape of the lens substrate 10 is not limited to this; each surface may be convex, concave, or flat. In a first embodiment of this manufacturing method, while the lens substrate 10 is rotating, the nozzle 20 discharging the film-forming composition is moved linearly from the first position through the center of the major axis of the lens substrate 10 to a second position, as indicated by the black arrow in FIG. 1 . When the nozzle 20 reaches the second position, it stops discharging the film-forming composition. Although Figure 1 shows the first embodiment in which the nozzle 20 passes through the center position of the long diameter of the lens substrate 10 and moves to the second position, a second embodiment in which the nozzle 20 stops discharging the film-forming composition at the center position of the long diameter may also be used.

[0034] As shown in FIG. 2 , the second position P2 is located on the opposite side of the first position P1 across the center O of the major axis of the lens substrate 10. In other words, the first position P1, the center O of the major axis, and the second position P2 are located on the same line in this order, and in the first mode, the nozzle 20 moves linearly along a line passing through these three points. In FIG. 2 , the lens substrate 10 is shown as an elliptical lens substrate (distance Z′ / distance Z = 1.0), but the lens substrate is not limited to this shape and may be any lens substrate that is not perfectly circular in plan view. In FIG. 2 , Z represents the proximity position Z. In FIG. 2 , the dashed circle represents a circle whose center is the center O of the major axis and whose radius is distance Z. The straight dashed line passing through the center O of the major axis represents a line (hereinafter also referred to as line Z) that passes through the first position P1, the center O of the major axis, and the second position P2, and whose distance from the center O of the major axis to both ends is distance Z. The nozzle 20 moves along line Z. In FIG. 2, for convenience, the lens substrate 10 is shown in a stationary state, but in this manufacturing method, the film-forming composition is discharged while the lens substrate 10 is rotated around the center position O of the major axis as the rotation center.

[0035] In FIG. 2 , the center position O of the major axis is defined as a position at a distance of 0.0% from the center position O of the major axis, position Z1 at one end of line Z (position at a distance Z from the center position O of the major axis) is defined as a position at a distance of 100% from the center position O of the major axis, and position Z2 at the other end of line Z (position at a distance Z from the center position O of the major axis) is defined as a position at a distance of −100% from the center position O of the major axis. The absolute value of the percentage is the absolute value of the percentage of the distance from the center position O of the major axis with respect to the distance Z. For example, in FIG. 2 , a position on line Z located on the position Z1 side of the center position O of the major axis and 10% of the distance Z from the center position O of the major axis is defined as a position at a distance of 10% from the center position O of the major axis. Furthermore, a position on line Z located on the position Z2 side of the center position O of the major axis and 10% of the distance Z from the center position O of the major axis is defined as a position at a distance of −10% from the center position O of the major axis. For example, when requirement 1 is satisfied, first position P1 is located at a distance of 83 to 97% of distance Z from center position O of the major axis. That is, in FIG. 2, first position P1 is located at a distance of −83 to −97% from center position O of the major axis. Furthermore, when requirement 1 is satisfied, second position P2 is located at a distance of more than 0 and not more than 55% of distance Z from center position O of the major axis. That is, in FIG. 2, second position P2 is located at a distance of more than 0 and not more than 55% of distance Z from center position O of the major axis.

[0036] In the spin coating method, the rotation speed of the lens substrate during the supply of the film-forming composition is preferably 300 to 700 rpm (rotation per minute), more preferably 400 to 600 rpm, and even more preferably 450 to 550 rpm, from the viewpoint of film thickness uniformity. The rotation speed of the lens substrate during the supply of the film-forming composition may be constant or may vary according to a predetermined program, but is preferably constant. After the supply of the film-forming composition, the rotation speed of the substrate may be changed to spread the film-forming composition over the entire surface of the lens substrate and remove unnecessary film-forming composition. The rotation speed of the lens substrate after the supply of the film-forming composition is not particularly limited, but is preferably equal to or higher than the rotation speed of the substrate during the supply of the film-forming composition, with the upper limit being preferably 3000 rpm or less, and more preferably 2500 rpm or less. The rotation speed of the lens substrate after the supply of the film-forming composition may be constant or may vary, and it is preferable to gradually increase the rotation speed.

[0037] The temperature of the lens substrate when the film-forming composition is supplied is not particularly limited, but is preferably 10 to 50°C, more preferably 15 to 40°C, from the viewpoint of the coating properties of the film-forming composition.

[0038] In the present disclosure, when discharging the film-forming composition, the nozzle moves linearly from a first position to the center of the major axis of the lens substrate or to a second position located on either side of the center of the major axis of the lens substrate. Discharge starts from the first position, and ends at the center of the major axis of the lens substrate when moving from the first position to the center of the major axis of the lens substrate, or at the second position when moving to the second position. The nozzle movement speed and discharge speed are controlled so that the discharge amount satisfies the above-mentioned requirements. The discharge amount of the film-forming composition from the start to the end of discharge is preferably 1.0 to 4.0 g, more preferably 1.5 to 3.5 g, and even more preferably 2.0 to 3.0 g. The inner diameter of the tip of the nozzle discharging the film-forming composition is preferably φ1.0 to 3.0, more preferably φ1.5 to 2.5. The discharge rate of the film-forming composition from the nozzle can be adjusted as needed, but is preferably 1.10 to 2.90 g / s, more preferably 1.60 to 2.80 g / s. The nozzle movement speed can be adjusted as appropriate, but is preferably 5.0 to 35.0 mm / s, more preferably 10.0 to 30.0 mm / s, and even more preferably 15.0 to 25.0 mm / s. The time for ejecting the film-forming composition can be adjusted as appropriate, but is preferably 1.0 to 1.9 seconds, and more preferably 1.1 to 1.7 seconds. The ejection speed and movement speed may be constant or may change during movement, but are preferably constant.

[0039] The thickness of the film formed by the lens manufacturing method of the present disclosure is not particularly limited, but is preferably 0.6 μm or more, more preferably 0.8 μm or more, and even more preferably 1.0 μm or more. The upper limit of the film thickness can be, for example, 30 μm or less. The above film thickness is an average film thickness, and is determined by measuring the film thickness at any five points on the film and arithmetically averaging the measured values.

[0040] After the film-forming composition is applied by spin coating, predetermined treatments such as drying and curing may be carried out as necessary to form a film.

[0041] The drying treatment is not particularly limited as long as it is a method that removes the solvent contained in the film-forming composition, and may be, for example, natural drying, a method in which dry air is blown, or heat drying.

[0042] The details of the curing treatment can be appropriately selected depending on the components contained in the film-forming composition, and examples thereof include a heat treatment and a light irradiation treatment. The temperature in the heat treatment may be any temperature that does not deform the lens substrate, and may be, for example, 30 to 100°C. The drying time may be, for example, 1 to 360 minutes. The light used in the light irradiation treatment is not particularly limited, and examples thereof include ultraviolet light and visible light. The light source may be a high-pressure mercury lamp. The integrated light amount in the light irradiation treatment is not particularly limited, and may be, for example, 100 to 3000 mJ / cm. ２ is preferred, and 100 to 1500 mJ / cm ２ The above-mentioned curing treatment may be carried out simultaneously with the drying treatment, or the drying treatment may also serve as the curing treatment.

[0043] The spin coating device used in the lens manufacturing method of the present disclosure is not particularly limited as long as it has a base that can fix and rotate the lens substrate and a nozzle that can eject the film-forming composition while moving in a predetermined direction, and any known spin coating device can be used.

[0044] [Film-forming composition] The film-forming composition contains components capable of forming a film. The film-forming composition preferably contains film-forming components and a solvent. The film-forming components can be selected appropriately depending on the application of the film. The solvent is not particularly limited as long as it is a solvent that can dissolve or disperse the film-forming components, and examples thereof include water and organic solvents. It is also preferable that the solvent contains water. The lens manufacturing method of the present disclosure can form a uniform film over the entire substrate surface while suppressing wraparound, even when using an aqueous composition that has high surface tension and is difficult to spread. The solvent may be a mixed solvent containing two or more solvents.

[0045] The viscosity of the film-forming composition at 20° C. is preferably 2.0 to 6.0 mPa·s, more preferably 3.0 to 5.0 mPa·s, and even more preferably 3.5 to 4.5 mPa·s. The viscosity can be measured using a known measuring device (for example, a cone-plate viscometer).

[0046] The solid content of the film-forming composition can be appropriately selected depending on the solid content, viscosity, etc., but is preferably 5 to 40% by mass, more preferably 10 to 30% by mass, and even more preferably 15 to 25% by mass.

[0047] Examples of the film-forming composition include a primer layer-forming composition and a hard coat layer-forming composition.

[0048] The primer layer-forming composition may be a known primer layer-forming composition, for example, containing a resin or a precursor thereof. Examples of the resin include polyurethane resin, epoxy resin, acrylic resin, phenolic resin, polyimide resin, polyester resin, bismaleimide resin, and polyolefin resin. Polyurethane resin, epoxy resin, or acrylic resin is preferred, and polyurethane resin is more preferred.

[0049] The primer layer-forming composition preferably contains a solvent in terms of ejection properties and full-surface application properties in a spin coating method. The solvent may be either water or an organic solvent, and preferably contains water. Examples of the organic solvent include alcohol solvents, ketone solvents, ether solvents, ester solvents, hydrocarbon solvents, halogenated hydrocarbon solvents, amide solvents, sulfone solvents, and sulfoxide solvents. Alcohol solvents, ester solvents, ketone solvents, or ether solvents are preferred, and alcohol solvents or ether solvents are more preferred. The solvent may be used alone or in combination of two or more.

[0050] The primer layer-forming composition is preferably an aqueous resin composition. The aqueous resin composition is a composition containing a resin component dissolved or dispersed as fine particles (preferably colloidal particles) in an aqueous solvent containing water. When the resin is dispersed in the aqueous resin composition in the form of fine particles, the particle size of the particles is preferably 0.3 μm or less in terms of dispersion stability. Examples of the aqueous solvent include water and mixed solvents of water and organic solvents that are miscible with water in any ratio, with water being preferred.

[0051] When the resin is a polyurethane resin, the primer layer-forming composition can be prepared by urethane-forming a high-molecular-weight polyol compound and an organic polyisocyanate compound, optionally with a chain extender, in a solvent that is inert to the reaction and has high affinity for water to form a prepolymer, neutralizing the prepolymer, and then dispersing it in an aqueous solvent containing the chain extender to increase the molecular weight. For examples of such polyurethane resins and compositions containing polyurethane resins, see paragraphs

[0009] to

[0013] of Japanese Patent No. 3,588,375, paragraphs

[0012] to

[0021] of Japanese Patent Publication No. 8-34897, paragraphs

[0010] to

[0033] of Japanese Patent Publication No. 11-92653, and paragraphs

[0010] to

[0033] of Japanese Patent Publication No. 11-92655, the contents of which are incorporated herein by reference. As a primer layer-forming composition containing a polyurethane resin, a commercially available aqueous urethane product may be used as is, or diluted with an aqueous solvent as needed. Examples of commercially available products include the "Evaphanol" series manufactured by Nicca Chemical Co., Ltd., the "Superflex" series manufactured by Dai-ichi Kogyo Seiyaku Co., Ltd., the "ADEKA Bontitor" series manufactured by ADEKA Corporation, the "Olestar" series manufactured by Mitsui Chemicals, Inc., the "Bondic" series and "Hydran" series manufactured by Dainippon Ink and Chemicals, Inc., the "Impranil" series manufactured by Bayer, the "Sofranate" series manufactured by Nippon Soflan Co., Ltd., the "Poise" series manufactured by Kao Corporation, the "Sunpren" series manufactured by Sanyo Chemical Industries, Ltd., the "Eizelax" series manufactured by Hodogaya Chemical Co., Ltd., and the "Neolet's" series manufactured by Zeneca Corporation.

[0052] The resin may be used alone or in combination of two or more. The resin content is preferably 5 to 40% by mass, more preferably 10 to 30% by mass, and even more preferably 15 to 25% by mass, relative to the total mass of the primer layer-forming composition. When the primer layer-forming composition contains a resin precursor, it is also preferable that the total amount of the resin and the resin precursor falls within the above-mentioned preferred range. The solvent content is preferably 60 to 95% by mass, more preferably 70 to 90% by mass, and even more preferably 75 to 85% by mass, relative to the total mass of the primer layer-forming composition.

[0053] The primer layer-forming composition may contain other components in addition to those described above. Examples of such other components include surfactants, antioxidants, dispersants, plasticizers, pH adjusters, metal oxide particles, hydrolyzable silicon compounds and / or their hydrolysis condensates, conductive fillers, matting agents, and colorants. The metal of the metal oxide particles may be at least one selected from Si, Al, Sn, Sb, Ta, Ce, La, Fe, Zn, W, Zr, In, and Ti. The metal oxide particles may contain only one of the metals (metal atoms) listed above, or two or more metals (metal atoms). The average particle size of the metal oxide particles is not particularly limited, but is preferably 1 to 200 nm, and more preferably 5 to 30 nm. Various functional groups may be introduced onto the surface of the metal oxide particles as needed.

[0054] When the primer layer-forming composition contains the other components, the content thereof is preferably 0.1 to 10 mass %, more preferably 0.1 to 5 mass %, based on the total mass of the primer layer-forming composition.

[0055] As the hard coat layer-forming composition, known hard coat layer-forming compositions can be used. Examples include organic hard coat layer-forming compositions, inorganic hard coat layer-forming compositions, and organic-inorganic hybrid hard coat layer-forming compositions. In the field of eyeglass lenses, organic-inorganic hybrid hard coat layers are commonly used.

[0056] The composition for forming a hard coat layer preferably contains an inorganic compound, such as an inorganic oxide or silsesquioxane.

[0057] The inorganic oxide is preferably a metal oxide particle. Examples of the metal oxide particle include oxide particles of one or more metals selected from the group consisting of Ti, Zr, Si, Al, Sn, Sb, Ta, Ce, La, Fe, Zn, W, and In, as well as composite metal oxide particles thereof. Composite metal oxide particles are oxide particles containing two or more metals (metal atoms). The inorganic oxide particle is preferably a SiO ２(silicon oxide), Al ２ O ３ (aluminum oxide), SnO ２ (tin oxide), ZrO ２ (zirconium oxide) and TiO ２ (titanium oxide), and SiO ２ and ZrO ２ More preferably, the material contains one or more selected from the group consisting of SiO ２ It is more preferable that the inorganic oxide particles contain SiO. Commercially available inorganic oxide particles may be used. ２ , Al ２ O ３ , SnO ２ , ZrO ２ , TiO ２ and composite oxide particles thereof, dispersed in water or an organic solvent.

[0058] Silsesquioxanes are silane compounds having a basic skeleton represented by formula (Q) that can be obtained by hydrolyzing trifunctional silane compounds such as alkoxysilanes, chlorosilanes, and silanols. Examples of silsesquioxane structures include irregular structures such as random structures, ladder structures, cage (fully condensed cage) structures, and incomplete cage structures (partially cleaved cage structures in which some silicon atoms are missing from the cage structure and some silicon-oxygen bonds in the cage structure are broken).

[0059] R Ｑ -SiO ３／２ (Q) In formula (Q), R Ｑ represents a monovalent organic group.

[0060] Examples of silsesquioxanes include the SQ series (eg, AC-SQ series and MAC-SQ series, manufactured by Toagosei Co., Ltd.).

[0061] The inorganic compound may be surface-treated. Examples of the surface treatment include the introduction of various functional groups and treatment using a known surface modifier. Examples of the functional group introduced onto the surface of the inorganic compound include a polymerizable group, and a (meth)acrylate group is preferred. When the inorganic compound has a (meth)acrylate group on the surface, it is preferred because it easily reacts with the resin that may be contained in the composition.

[0062] The average particle size of the inorganic compound is preferably 0.5 to 200 nm, more preferably 1 to 50 nm.

[0063] When the composition for forming a hard coat layer contains an inorganic compound, the content of the inorganic compound is preferably 10.0 to 80.0 mass %, more preferably 20.0 to 70.0 mass %, and still more preferably 30.0 to 60.0 mass %, based on the total solid content of the composition for forming a hard coat layer.

[0064] The hard coat layer-forming composition may contain components other than inorganic compounds. Examples of the components that the hard coat layer-forming composition may contain include polymerizable monomers, polymerization initiators, ultraviolet absorbers, surfactants, antioxidants, plasticizers, pH adjusters, coating film adjusters, light stabilizers, antioxidants, color inhibitors, dyes, fillers, internal mold release agents, hydrolyzable silicon compounds and / or their hydrolysis condensates, conductive fillers, matting agents, and coloring materials.

[0065] The composition for forming a hard coat layer preferably contains a solvent in terms of ejection properties and full-surface application properties in a spin coating method. The solvent may be either water or an organic solvent. Examples of the organic solvent include the organic solvents that may be contained in the composition for forming a primer layer described above, and an alcohol solvent is preferred. The alcohol solvent is preferably an alcohol solvent having 10 or less carbon atoms, and more preferably an alcohol solvent having 5 or less carbon atoms (e.g., isopropanol). The alcohol solvent may also be a polyhydric alcohol having two or more hydroxy groups in one molecule. The solvent may be used alone or in combination of two or more types.

[0066] The content of the total solid content in the hard coat layer-forming composition is preferably 10 to 90 mass %, more preferably 40 to 80 mass %, based on the total mass of the film-forming composition.

[0067] The film-forming composition may be prepared by mixing the components described above. The mixing method is not particularly limited, and known methods can be used.

[0068] [Other Steps] The method for manufacturing a lens according to the present disclosure may include other steps as long as it includes a step of forming a film by applying the above-described film-forming composition using a predetermined spin coating method.

[0069] The lens manufacturing method of the present disclosure may include a step of forming other layers on the film. Examples of other layers include a hard coat layer, an anti-reflection layer, a water-repellent layer, an antifouling layer, and an anti-fogging layer. Known methods can be used to form the other layers.

[0070] The lens manufacturing method of the present disclosure may include other steps prior to the formation of the film. Examples of such other steps include a prewetting step. The prewetting treatment is not particularly limited as long as it can form a coating film of the prewetting liquid on the substrate surface. Examples of prewetting treatment methods include dipping coating, spin coating, spray coating, inkjet coating, and flow coating, with spin coating being preferred in terms of achieving uniform prewetting. Known organic solvents can be used as the prewetting liquid. Examples of the organic solvent include alcohol solvents, ether solvents, and ester solvents, with alcohol solvents being preferred.

[0071] The method for manufacturing a lens according to the present disclosure may include the step of forming the lens substrate described above. Specifically, for example, the method may include the step of forming another layer, such as a primer layer, on the plastic lens.

[0072] <Lens> Lenses obtained by the lens manufacturing method of the present disclosure will now be described. FIG. 3 shows an example of a lens obtained by the lens manufacturing method of the present disclosure. The lens 40 shown in FIG. 3 has a plastic lens 30, a primer layer 32, a hard coat layer 34, an anti-reflection film 36, and a water- and oil-repellent layer 38, in this order. It is preferable that at least one of the primer layer 32 and the hard coat layer 34 of the lens is a film formed by the manufacturing method of the present disclosure, and it is more preferable that the primer layer 32 is a film formed by the manufacturing method of the present disclosure. In the lens 40 shown in FIG. 3, the primer layer 32, the hard coat layer 34, the anti-reflection film 36, and the water- and oil-repellent layer 38 are formed in this order on one side of the plastic lens 30. However, in FIG. 3, the primer layer, the hard coat layer, the anti-reflection film, and the water- and oil-repellent layer may also be formed in this order on the surface of the plastic lens 30 opposite the primer layer 32 side. 3, one or more of the primer layer 32, hard coat layer 34, anti-reflection coating 36, and water- and oil-repellent layer 38 may be omitted. However, the lens 40 has at least one of the primer layer 32 and the hard coat layer 34. The plastic lens 30 and primer layer 32 are as described above, and preferred embodiments are also as described above. Below, we will explain the anti-reflection coating and water- and oil-repellent layer that the lens obtained by the lens manufacturing method of the present disclosure (hereinafter simply referred to as the "obtained lens") may have.

[0073] [Primer Layer] The primer layer improves the adhesion of the formed film to the lens and can impart impact resistance to the resulting lens. The primer layer may be formed on only one side of the plastic lens, or on both sides of the plastic lens.

[0074] The material constituting the primer layer is not particularly limited, and known materials can be used, for example, a layer formed using the above-mentioned primer layer-forming composition. The method for forming the primer layer is not particularly limited, and known methods can be used, for example, a method in which a primer layer-forming composition containing a predetermined resin is applied to a plastic lens, and a curing treatment is performed as necessary to form a primer layer. Examples of methods for applying the primer layer-forming composition to a plastic lens include the method of applying the above-mentioned film-forming composition. Other known methods, such as dipping coating, spin coating, spray coating, inkjet coating, and flow coating, can also be used. It is also preferable to form a primer layer on a plastic lens using this manufacturing method.

[0075] The thickness of the primer layer is not particularly limited, but is more preferably 0.3 to 2 μm.

[0076] [Hard Coat Layer] The hard coat layer is preferably disposed on the primer layer, and more preferably disposed between the primer layer and the antireflection layer. When the lens has a hard coat layer, the scratch resistance of the lens can be improved. The hard coat layer preferably exhibits a hardness of H or higher in pencil hardness according to JIS K5600. As the hard coat layer, a known hard coat layer can be used, and examples thereof include an organic hard coat layer, an inorganic hard coat layer, and an organic-inorganic hybrid hard coat layer. For example, in the field of eyeglass lenses, an organic-inorganic hybrid hard coat layer is commonly used.

[0077] As a method for forming a hard coat layer, for example, a method can be mentioned in which a composition for forming a hard coat layer is applied to a desired member to form a coating film, and the coating film is subjected to a curing treatment (for example, a light irradiation treatment and a drying treatment) as necessary to form a hard coat layer. As a method for applying a composition for forming a hard coat layer to a substrate, for example, the method of applying the above-mentioned film-forming composition and the method exemplified as the method of applying the above-mentioned composition for forming a primer layer to a plastic lens can be mentioned. A hard coat layer can also be formed using this production method.

[0078] The thickness of the hard coat layer is preferably from 1 to 20 μm, more preferably from 2 to 18 μm.

[0079] [Anti-reflection film] The obtained lens may have an anti-reflection film. The anti-reflection film is preferably disposed on the opposite side of the film from the plastic lens. The anti-reflection film is a layer that has the function of preventing reflection of incident light. Specifically, it can have low reflection characteristics (broadband low reflection characteristics) over the entire visible range of 380 to 780 nm.

[0080] The structure of the antireflective film is not particularly limited, and may be a single-layer structure or a multilayer structure. An inorganic antireflective film is preferred as the antireflective film. An inorganic antireflective film is an antireflective film composed of an inorganic compound. In the case of a multilayer structure, a structure in which low-refractive-index layers and high-refractive-index layers are alternately stacked is preferred. Examples of materials constituting the high-refractive-index layers include oxides of titanium, zirconium, aluminum, niobium, tantalum, or lanthanum. Examples of materials constituting the low-refractive-index layers include oxides of silica. The method for producing the antireflective film is not particularly limited, and examples include dry methods such as vacuum deposition, sputtering, ion plating, ion-beam assisted deposition, and CVD.

[0081] [Water- and oil-repellent layer] The resulting lens may include a water- and oil-repellent layer. The water- and oil-repellent layer is preferably disposed as the outermost layer of the lens. The water- and oil-repellent layer reduces the surface energy of the lens, improving the lens's anti-contamination function and improving the lubricity of the lens surface, thereby improving the lens's abrasion resistance. The water- and oil-repellent layer is preferably provided when the resulting lens is a lens for glasses.

[0082] The material constituting the water- and oil-repellent layer is not particularly limited, and examples thereof include fluorine-containing compounds (compounds containing fluorine atoms) and silicon-containing compounds (compounds containing silicon atoms). Among these, the water- and oil-repellent layer preferably contains a fluorine-containing compound, and more preferably contains at least one selected from the group consisting of fluorine-substituted alkyl group-containing organosilicon compounds, their hydrolysates, and their hydrolyzed condensates. The material constituting the water- and oil-repellent layer may be used alone or in combination of two or more.

[0083] The organosilicon compound containing fluorine-substituted alkyl group is the organosilicon compound that contains alkyl group in which part or all of hydrogen atom is replaced by fluorine atom, and has hydrolyzable group.Here, the hydrolyzable group is the group that is directly bonded to silicon atom and can proceed hydrolysis reaction and condensation reaction, for example, alkoxy group, halogen atom, acyloxy group, alkenyloxy group and isocyanate group.It should be noted that when a plurality of hydrolyzable groups are directly bonded to one silicon atom, they can be the same or different.

[0084] The hydrolyzate of a fluorine-substituted alkyl group-containing organosilicon compound refers to a compound obtained by hydrolyzing the hydrolyzable groups in a fluorine-substituted alkyl group-containing organosilicon compound. The hydrolyzate may be one in which all of the hydrolyzable groups are hydrolyzed (complete hydrolyzate) or one in which only a portion of the hydrolyzable groups are hydrolyzed (partial hydrolyzate). In other words, the hydrolyzate may be a complete hydrolyzate, a partial hydrolyzate, or a mixture thereof. The hydrolyzed condensate of a fluorine-substituted alkyl group-containing organosilicon compound refers to a compound obtained by hydrolyzing the hydrolyzable groups in a fluorine-substituted alkyl group-containing organosilicon compound and condensing the resulting hydrolyzate. The hydrolyzed condensate may be one in which all of the hydrolyzable groups are hydrolyzed and the hydrolyzate is completely condensed (complete hydrolyzed condensate), or one in which only a portion of the hydrolyzable groups are hydrolyzed and a portion of the hydrolyzate is condensed (partial hydrolyzed condensate). In other words, the hydrolyzed condensate may be a complete hydrolyzed condensate, a partial hydrolyzed condensate, or a mixture thereof.

[0085] There are no particular restrictions on the thickness of the water- and oil-repellent layer of the resulting lens, but it is preferably 5 to 35 nm.

[0086] The method for forming the water- and oil-repellent layer is not particularly limited and can be selected as desired depending on the materials used, the desired performance, thickness, etc. Examples include a method in which a water- and oil-repellent layer-forming composition containing a fluorine-substituted alkyl group-containing organosilicon compound is applied to a substrate and cured as needed, and a dry method. Coating methods include, for example, dip coating, roll coating, bar coating, spin coating, spray coating, die coating, and gravure coating. Curing treatments include, for example, light irradiation treatment, heat treatment, and water vapor contact treatment. Water vapor contact treatments include, for example, contact with air controlled at a humidity of 50 to 90% RH. The above curing treatments may be performed in combination. Examples of dry methods include the same methods as those used for the antireflective coating described above.

[0087] <Uses> Lenses obtained by the lens manufacturing method of the present disclosure are suitable for use in various lens applications, and are particularly suitable for use as lenses for eyeglasses.

[0088] The present disclosure will be explained in more detail below using examples, but the present disclosure is not limited to these examples in any way.

[0089] [Preparation of Film-Forming Composition] The components were mixed to obtain the composition shown in Table 1, thereby obtaining a film-forming composition with a solids concentration of 20% by mass. The viscosity of the film-forming composition at 20°C was 4 mPa·s. An aqueous urethane dispersion (Evaphanol HA170, manufactured by Nicca Chemical Co., Ltd., solids concentration 37% by mass) was used as the polyurethane resin, and the solids content was adjusted to the polyurethane resin content shown in Table 1 below. 501W ADDITIVE (manufactured by Dow Chemical) and L7001 (manufactured by Dow Chemical) were used as surfactants in a mass ratio of 501W ADDITIVE / L7001 = 1 / 1.

[0090]

[0091] [Film Formation] An elliptical lens substrate (a lens having a refractive index of 1.60 (Nikon Lite 3AS material, manufactured by Nikon Essilor Corporation) with a minor axis of 50 mm and a major axis of 70 mm was prepared as the lens substrate. In the above lens substrate, the distance Z was 25 mm. The lens substrate was placed on a spin coater so that the center of rotation was the center of the long axis of the lens substrate, and the rotation speed of the substrate was increased to 500 rpm in 0.1 seconds from the start of rotation. While rotating at 500 rpm, the nozzle was moved from a predetermined first position to a second position shown in the table below, and the film-forming composition was ejected from the nozzle. The nozzle movement speed was 20 mm / s, and the ejection speed was adjusted so that the ejection amount from the start of ejection at the first position to the end of ejection at the second position was 2.0 g, 2.5 g, or 3.0 g. When the ejection amount was 2.0 g, 2.5 g, or 3.0 g, the ejection amount per unit area in the plan view of the lens was 0.00073 g / mm, respectively. ２ ,0.00091g / mm ２ , or 0.00110 g / mm ２The rotational speed was then increased to 800 rpm in 5 seconds, followed by rotation for 7 seconds, and then increased to 2000 rpm in 0.1 seconds, followed by rotation for 5 seconds, forming a coating film on the substrate. The coating was then dried by heating at 60°C for 30 minutes, forming a film with a thickness of 0.8 to 1.0 μm. In the table below, the positions of the first and second positions are indicated by the coordinate axes shown in FIG. 2. For example, when the first position is -90.0% and the second position is 20.0%, the nozzle moves linearly from the first position to the second position, and the first and second positions are located on opposite sides of the center of the major axis of the lens substrate, with the first position being 22.5 mm from the center of the major axis and the second position being 5 mm from the center of the major axis. Also, for example, when the first position is -90.0% and the second position is 0.0%, the nozzle moves in a straight line from the first position to the center position of the long axis of the lens substrate, and the first position is 22.5 mm from the center of the long axis of the lens substrate.

[0092] <Evaluation> [Wrap-around] The lenses obtained by the above procedure were checked under a table fluorescent lamp to see if the film-forming composition had wrapped around the rear surface of the lens substrate, and were evaluated according to the following evaluation criteria. For practical purposes, a rating of C or higher is preferable for wrap-around evaluation. Note that the wrap-around below refers to how many mm of the film-forming composition has wrapped around from the edge of the lens substrate when observing the rear surface of the lens substrate. A: No wrap-around B: Wrap-around is more than 0 mm and 1 mm or less C: Wrap-around is more than 1 mm and 2 mm or less D: Wrap-around is more than 2 mm

[0093] Tables 2 to 4 show the discharge amount of the film-forming composition, the first position, the second position, and the evaluation results. Regarding how to read the following tables, for example, in Table 2, when the first position is -93.0% and the second position is 20.0%, the evaluation is "A." As another example, when the first position is -100.0% and the second position is 50.0%, the evaluation is "D."

[0094]

[0095]

[0096]

[0097] [Full-surface coating property] The lenses obtained by the above procedure were checked for uncoated areas on the surface of the lens substrate under a table fluorescent lamp and evaluated according to the following evaluation criteria. For the evaluation of full-surface coating property, a rating of C or higher is preferable in practice. The uncoated areas below indicate the range in mm from the edge of the lens substrate where the film-forming composition is not applied when the lens is observed. A: No uncoated area B: Uncoated area is more than 0 mm and 1 mm or less C: Uncoated area is more than 1 mm and 2 mm or less D: Uncoated area is more than 2 mm

[0098] Tables 5 to 7 show the discharge amount of the film-forming composition, the first position, the second position, and the evaluation results. For example, in Table 5, if the first position is -93.0% and the second position is 20.0%, the evaluation is "C." As another example, if the first position is -95.0% and the second position is 50.0%, the evaluation is "B."

[0099]

[0100]

[0101]

[0102] [Smoothness] The film formed on the lens obtained by the above procedure was observed under a table fluorescent lamp or an ultra-high pressure mercury lamp, and evaluated according to the following evaluation criteria. For practical purposes, a smoothness rating of C or higher is preferable. Note that "without a light source" below means that the observation was made under room light without using a table fluorescent lamp or an ultra-high pressure mercury lamp. A: No unevenness is visible under the ultra-high pressure mercury lamp. B: Unevenness is visible under the ultra-high pressure mercury lamp, but not under the table fluorescent lamp. C: Unevenness is visible under the table fluorescent lamp. D: Unevenness is visible without a light source.

[0103] Tables 8 to 10 show the amount of the film-forming composition dispensed, the first and second positions, and the evaluation results.

[0104]

[0105]

[0106]

[0107] [Overall Evaluation] Based on the evaluation results of wraparound, full surface coating ability, and smoothness, the film-forming ability of this production method was evaluated according to the following evaluation criteria. In practice, an evaluation of C or higher is preferable. A: Wraparound, full surface coating ability, and smoothness are all rated A. B: At least one of wraparound, full surface coating ability, and smoothness is rated B, and the others are rated A or B. C: At least one of wraparound, full surface coating ability, and smoothness is rated C, and the others are rated A, B, or C. D: At least one of wraparound, full surface coating ability, and smoothness is rated D.

[0108] Tables 11 to 13 show the amount of the film-forming composition dispensed, the first and second positions, and the evaluation results.

[0109]

[0110]

[0111]

[0112] The evaluation results confirmed that the lens manufacturing method of the present disclosure can prevent the film-forming composition from spreading onto the back surface of the lens substrate, allowing a film to be formed over the entire surface of the lens substrate, and that the resulting film has excellent smoothness.

[0113] The above evaluation results confirmed that when requirement 1 is met, if the first position is located at a distance of 87 to 97% of the distance Z from the center position of the major axis, the overall coating property is superior, and if the first position is located at a distance of 89 to 97% of the distance Z, the overall coating property is even superior. The above evaluation results confirmed that when requirement 1 is met, if the second position is located at a distance of more than 0% but not more than 45% of the distance Z from the center position of the major axis, the smoothness is superior, and if the second position is located at a distance of more than 0% but not more than 35% of the distance Z, the smoothness is even superior. The above evaluation results confirmed that when requirement 2 is met, if the second position is located at a distance of more than 0% but not more than 45% of the distance Z from the center position of the major axis, the smoothness is superior, and if the second position is located at a distance of more than 0% but not more than 35% of the distance Z, the smoothness is even superior. The above evaluation results confirmed that when requirement 3 is met, if the first position is located at a distance of 85 to 97% of the distance Z from the center position of the major axis, the overall coating property is even superior. From the above evaluation results, it was confirmed that when requirement 1 is satisfied, smoothness is superior when the second position is located at a distance greater than 0% and not more than 35% of the distance Z from the center position of the major axis.

[0114] Discharge rate: 0.00073 g / mm ２ to 0.00062 g / mm ２ When the discharge rate was changed to 0.00073 g / mm, the same results as those in Tables 2, 5, 8, and 11 were obtained. ２ to 0.00078 g / mm ２ When the discharge rate was changed to 0.00091 g / mm, the same results as those in Tables 2, 5, 8, and 11 were obtained. ２ to 0.00082 g / mm ２ When the discharge rate was changed to 0.00091 g / mm, the same results as those in Tables 3, 6, 9, and 12 were obtained. ２ to 0.00098 g / mm ２ When the discharge rate was changed to 0.00110 g / mm, the same results as those in Tables 3, 6, 9, and 12 were obtained. ２ to 0.00102 g / mm ２When the discharge amount was changed to 0.00110 g / mm, the same results as those in Tables 4, 7, 10, and 13 were obtained. ２ to 0.00125 g / mm ２ When the value was changed to , the same results as those in Tables 4, 7, 10, and 13 were obtained.

[0115] 10 Lens substrate 20 Nozzle 30 Plastic lens 32 Primer layer 34 Hard coat layer 36 Anti-reflection film 38 Water-repellent and oil-repellent layer 40 Lens P1 First position P2 Second position O Center position of major axis of lens substrate Z Proximity position Z Z1 Position Z1 Z2 Position Z2

Claims

1. A method for manufacturing a lens, which comprises applying a film-forming composition to a lens substrate that is not perfectly circular in plan view by spin coating to form a film, and manufacturing a lens, wherein, when, in plan view of the lens substrate, the position on the outer edge of the lens substrate that is closest to the center position of the major axis of the lens substrate is defined as the proximity position, and the distance from the center position of the major axis to the proximity position is defined as distance Z, in the spin coating method, the lens substrate is rotated around the center position of the major axis as the center of rotation, and when the film-forming composition is discharged while moving a nozzle that discharges the film-forming composition from its tip in a straight line from a first position to the center position of the major axis, or through the center position of the major axis to a second position that is located between the first position and the center position of the major axis, any of the following requirements 1 to 3 is satisfied: Requirement 1. The amount of the film-forming composition discharged per unit area in plan view of the lens substrate is 0.00100 g / mm ２ 0.00130g / mm or more ２ Requirement 2: The amount of the film-forming composition discharged per unit area in a plan view of the lens substrate is 0.00080 g / mm or less, the first position is located at a position away from the center position of the major axis by a distance of 83 to 97% of the distance Z, and the second position is located at a position away from the center position of the major axis by a distance of more than 0% but not more than 55% of the distance Z. ２ 0.00100g / mm or more ２ Requirement 3: The amount of the film-forming composition discharged per unit area in a plan view of the lens substrate is less than 0.00060 g / mm ２ 0.00080g / mm or more ２ the first position is located at a distance of 93 to 97% of the distance Z from the center position of the major axis, and the second position is located at a distance of more than 0% and not more than 45% of the distance Z from the center position of the major axis.

2. The method for manufacturing a lens according to claim 1, wherein requirement 1 is satisfied, and the first position is located at a distance of 89 to 97% of the distance Z from the center of the major axis, and the second position is located at a distance of more than 0% and not more than 35% of the distance Z from the center of the major axis, or requirement 2 is satisfied, and the first position is located at a distance of 91 to 97% of the distance Z from the center of the major axis, and the second position is located at a distance of more than 0% and not more than 35% of the distance Z from the center of the major axis.

3. The method for producing a lens according to claim 1 or 2, wherein the film-forming composition contains water.

4. The method for manufacturing a lens according to any one of claims 1 to 3, wherein the aspect ratio of the lens substrate is greater than 1.0 and not more than 1.5.

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