Contact lens package

Abstract

An embodiment of the present invention provides a contact lens package including: a package having a lid member and a bottom member; and a contact lens accommodated in a deformed state in an accommodation space sealed by the lid member and the bottom member, wherein the contact lens has a relaxation modulus of 1.6 MPa or less, and the relaxation modulus of the contact lens is the modulus of elasticity one second after the start of measurement when a contact lens piece in an aqueous medium at a temperature of 35ºC is subjected to a strain of 75% with respect to the upper limit of a linear deformation region in a tensile test while simultaneously starting measurement of the stress required to hold the contact lens piece.

Description

Contact Lens Package

[0001] The present invention relates to a contact lens package.

[0002] Conventional disposable contact lenses are generally stored in a package consisting of a cover and a base, with the lens storage space being higher than the natural sagittal height of the contact lens, together with a storage solution.

[0003] In recent years, from the viewpoint of reducing plastic waste and saving space, thin contact lens packages have been proposed in which a contact lens is housed in a thin package that is thinner than the natural sagittal height of the contact lens (for example, Patent Document 1).

[0004] Japanese Patent Application Laid-Open No. 2005-234576

[0005] When a contact lens is taken out of a thin contact lens package and worn, the wearer may experience discomfort when wearing the lens. The main object of the present invention is to improve the discomfort when wearing a contact lens taken out of a thin contact lens package.

[0006] [1] According to one aspect of the present invention, there is provided a contact lens package comprising a package having a lid member and a bottom member, and a contact lens contained in a deformed state in a storage space sealed by the lid member and the bottom member, wherein the relaxation modulus of the contact lens is 1.6 MPa or less, and the relaxation modulus of the contact lens is the modulus measured 1 second after the start of measurement when a contact lens piece is subjected to a strain of 75% of the upper limit of the linear elastic region in a tensile test in an aqueous medium at 35° C. [2] In the contact lens package described in [1] above, the tensile loss tangent of the contact lens, as measured by dynamic tensile viscoelasticity measurement in an aqueous medium at 35° C., may be 0.14 or less. [3] In the contact lens package described in [1] or [2] above, the relaxation modulus of the contact lens may be 1.3 MPa or less. [4] According to another aspect of the present invention, there is provided a contact lens package comprising a package having a lid member and a bottom member, and a contact lens contained in a deformed state in a storage space sealed by the lid member and the bottom member, wherein the tensile loss tangent of the contact lens, as determined by dynamic tensile viscoelasticity measurement in an aqueous medium at 35° C., is 0.1 or less. [5] In the contact lens package described in [4] above, the tensile loss tangent of the contact lens may be 0.06 or less. [6] In the contact lens package described in [4] or [5] above, the contact lens may have a relaxation modulus of 1.8 MPa or less, the relaxation modulus being the modulus measured 1 second after the start of measurement when a contact lens piece is subjected to a strain of 75% of the upper limit of the linear elastic region in a tensile test in an aqueous medium at 35° C. and simultaneously measurement of the stress required to hold the contact lens piece is started.[7] According to another aspect of the present invention, there is provided a contact lens package comprising a package having a lid member and a bottom member, and a contact lens contained in a deformed state in a storage space sealed by the lid member and the bottom member, wherein the tensile loss tangent of the contact lens, as measured by dynamic tensile viscoelasticity measurement in an aqueous medium at 35°C, is 0.1 or less, and the relaxation modulus of the contact lens is 1.6 MPa or less, the relaxation modulus being the modulus measured 1 second after the start of measurement when a contact lens piece is subjected to a strain of 75% of the upper limit of the linear elastic region in a tensile test in an aqueous medium at 35°C and the stress required to hold the contact lens piece is simultaneously measured. [8] In the contact lens package described in [7] above, the tensile loss tangent of the contact lens may be 0.06 or less. [9] In the contact lens package described in [7] or [8] above, the relaxation modulus of the contact lens may be 1.2 MPa or less.

[10] In the contact lens package according to any one of [1] to [9] above, the oxygen permeability (Dk / t) of the contact lens may be 24 or more.

[11] In the contact lens package according to any one of [1] to

[10] above, the contact lens may be a silicone hydrogel lens.

[12] In the contact lens package according to any one of [1] to

[11] above, the contact lens may be accommodated in the accommodation space with its height smaller than its natural sagittal height.

[13] In the contact lens package according to any one of [1] to

[12] above, the height of the accommodation space may be 2 mm or less.

[14] According to another aspect of the present invention, there is provided a method for improving the recovery of wrinkles in a contact lens when a contact lens package is opened, the method comprising: producing a contact lens package by joining a lid member and a bottom member facing each other so as to form a sealed storage space in which a contact lens is placed, the height of the storage space being smaller than the natural sagittal height of the contact lens, the contact lens having a relaxation modulus of 1.6 MPa or less, the relaxation modulus of the contact lens being the modulus of elasticity measured 1 second after the start of measurement when a contact lens piece is subjected to a strain of 75% of the upper limit of the linear elastic region in a tensile test in an aqueous medium at 35°C and simultaneously measurement of the stress required to hold the contact lens piece is started.

[15] According to another aspect of the present invention, there is provided a method for suppressing the occurrence of wrinkles in a contact lens in a contact lens package, comprising: producing a contact lens package by joining a lid member and a bottom member opposed to each other so as to form a sealed storage space in which a contact lens is placed, wherein the height of the storage space is smaller than the natural sagittal height of the contact lens, and wherein at least one of the following is satisfied: (i) the tensile loss tangent of the contact lens, as determined by dynamic tensile viscoelasticity measurement in an aqueous medium at 35°C, is 0.1 or less; and (ii) the rate of energy released for shrinking the contact lens from a stretched state to a stretch ratio of 0% to energy absorbed when the contact lens is stretched to a stretch ratio of 100% in an aqueous medium at 35°C is 90% or more.

[16] According to another aspect of the present invention, there is provided a contact lens package comprising: a package having a lid member and a bottom member; and a contact lens contained in a storage space sealed by the lid member and the bottom member, wherein the storage space is defined by a convex curved surface portion of the lid member that protrudes toward the bottom member and a concave curved surface portion of the bottom member that protrudes on the side of the bottom member opposite the lid member, and wherein the package is configured so that the contact lens adheres to the lid member or the bottom member when the package is opened, and wherein at least one of the following is satisfied: (i) the relaxation modulus of the contact lens is 1.6 MPa or less, and the relaxation modulus of the contact lens is the modulus of elasticity measured 1 second after the start of measurement when a contact lens piece is subjected to a strain of 75% of the upper limit of the linear elastic region in a tensile test in an aqueous medium at 35°C and the measurement of the stress required to hold the contact lens piece is started simultaneously; and (ii) the tensile loss tangent of the contact lens measured in dynamic tensile viscoelasticity measurement in an aqueous medium at 35°C is 0.1 or less.

[0007] According to an embodiment of the present invention, a contact lens having predetermined physical properties is used as the contact lens contained in the thin package, which can improve the initial visual discomfort after wearing the contact lens even when the contact lens is taken out of the thin package and worn immediately.

[0008] Thinner packaging leads to a reduction in plastic and other waste, and so the thin contact lens package according to the embodiment of the present invention also contributes to the achievement of the 17 goals and 169 targets of the SDGs (Sustainable Development Goals), particularly "12. Responsible Consumption and Production" and "14. Protect and sustainably use the water below sea level."

[0009] FIG. 1A is a schematic top view of a contact lens package according to one embodiment of the present invention. FIG. 1B is a schematic bottom view of the contact lens package shown in FIG. 1A. FIG. 1C is a schematic cross-sectional view of the contact lens package shown in FIG. 1A taken along line A-A. FIG. 1D is an exploded perspective view of the contact lens package shown in FIG. 1A. FIG. 2 is a schematic perspective view of an example of a package in an opened state. FIG. 3 is a diagram illustrating the natural sagittal height of a contact lens. FIG. 4A is a schematic cross-sectional view of a lens-loading substrate used in the contact lens package shown in FIG. 1A. FIG. 4B is a schematic cross-sectional view of an example of a lens-loading substrate. FIG. 5 is a schematic cross-sectional view of a contact lens package according to one embodiment of the present invention. FIG. 6 is a schematic cross-sectional view of the bottom member of the contact lens package shown in FIG. 5. FIG. 7 is a schematic cross-sectional view of a contact lens package according to one embodiment of the present invention. (a) is a schematic cross-sectional view of the lid member of the contact lens package shown in FIG. 7, and (b) is a schematic cross-sectional view of the bottom member of the contact lens package shown in FIG. 7. FIG. 9 is a diagram illustrating a method for preparing a measurement sample. FIG. 1A is a diagram showing the power distribution of a contact lens in which all ring regions have a Q value of 2 or more, and FIG. 1B is a diagram showing the power distribution of a contact lens in which all ring regions have a Q value of 2 or less.

[0010] Representative embodiments of the present invention will be described below, but the present invention is not limited to these embodiments. Each embodiment can be combined as appropriate unless it is clearly inappropriate. For clarity, the drawings are shown schematically, and the thickness and size of each component and the thickness and other ratios between components in the drawings are different from the actual ones.

[0011] In this specification, the surface of a contact lens that comes into contact with the eye may be referred to as the inner surface, and the opposite surface as the outer surface.

[0012] In this specification, "monomer" means a polymerizable compound having one or more polymerizable groups. Preferred examples of the polymerizable group include ethylenically unsaturated groups, and the polymerizable group may be, for example, a (meth)acryloyl group, a vinyl group, a styryl group, or an allyl group. Here, "(meth)" means any methyl substitution. Therefore, "(meth)acryloyl" means methacryloyl and / or acryloyl. The same applies to other descriptions such as "(meth)acrylic."

[0013] [Contact Lens Package] According to one aspect of the present invention, there is provided a contact lens package including a package having a lid member and a base member, and a contact lens contained in a storage space sealed by the lid member and the base member. In the sealed storage space, the contact lens may be in a state in which at least a portion of the contact lens is deformed. The deformation of the contact lens may be within a range that allows the contact lens to recover to a state in which it can be worn after the storage space is opened, and may be in a state in which at least a portion of the hemispherical shape formed to fit the corneal curve is folded, twisted, bent, crushed, rolled, or the like. For example, in the sealed storage space, the contact lens may be in a state in which its height is smaller than its natural sagittal height and / or its diameter is smaller than its natural diameter (DIA).

[0014] The standard deviation of the diopter distribution in a predetermined region of a contact lens immediately after opening a contact lens package according to an embodiment of the present invention (e.g., within 15 seconds after opening) is typically 3 or less, e.g., 2 or less, preferably 1.5 or less, more preferably 1 or less, and even more preferably 0.5 or less. The lower limit of the standard deviation of the diopter distribution is not particularly limited, but may be, for example, 0.01 or more. A small standard deviation of the diopter distribution means that there is little power unevenness on the surface of the contact lens, and as a result, the discomfort of vision can be reduced. The standard deviation of the diopter distribution can be obtained as a Q value by measurement using, for example, an underwater power meter ("VC-2001" manufactured by Visionix). The predetermined region to be measured for the diopter distribution can be, for example, a ring region within a radius of 5 mm from the center of the contact lens, a spot region within a radius of 5 mm, or a spot region within a radius of 3 mm.

[0015] The standard deviation of the power distribution in a predetermined region of the contact lens 900 seconds after opening a contact lens package according to an embodiment of the present invention is typically 3 or less, for example 2 or less, preferably 1.5 or less, more preferably 1 or less, and even more preferably 0.5 or less. The lower limit of the standard deviation of the power distribution is not particularly limited, but may be, for example, 0.01 or more.

[0016] Fig. 1A is a schematic top view of a contact lens package according to one embodiment of the present invention, Fig. 1B is a schematic bottom view of the contact lens package shown in Fig. 1A, Fig. 1C is a schematic cross-sectional view of the contact lens package shown in Fig. 1A taken along line A-A, and Fig. 1D is an exploded perspective view of the contact lens package shown in Fig. 1A. Also, Fig. 2 is a schematic perspective view of an example of the package in an opened state.

[0017] 1A to 1D, a contact lens package 200A includes a package 100 having a cover member 10 and a base member 20, and a contact lens 120 accommodated in a storage space 110 sealed by the cover member 10 and the base member 20. Although not shown, a contact lens storage solution is also accommodated in the storage space 110, thereby maintaining the contact lens 120 in a hydrated state. The contact lens 120 is accommodated in the storage space 110 in a deformed state, specifically, in a state in which its height is smaller than its natural sagittal height, and may be in a flattened state, for example. The natural sagittal height of the contact lens refers to the height of the outer surface of the lens when the hydrated contact lens is placed with its inner surface facing down on a horizontal surface, and is the height indicated by "T" in FIG. 3.

[0018] As shown in FIGS. 1A to 1D and 2, the package 100 is composed of a cover member 10 and a bottom member 20 .

[0019] The cover member 10 is made of, for example, a flexible film substrate, and examples of the material for forming the film substrate include inorganic materials such as aluminum, polyolefin resins such as polyethylene (PE) and polypropylene (PP), polyester resins such as polyethylene terephthalate (PET), and polyamide resins.

[0020] The film substrate may have a single-layer structure or a laminated structure. In one embodiment, the film substrate may have a single-layer structure made of a resin film (e.g., a PP film, a PET film) or a metal foil (e.g., an aluminum foil). In another embodiment, the film substrate may have a two-layer structure including a resin layer (e.g., a PP film, a PET film) and an aluminum layer (e.g., an aluminum vapor-deposited layer) disposed on one side thereof. In another embodiment, the film substrate may have a three-layer structure including a first resin layer, an aluminum layer, and a second resin layer.

[0021] In the illustrated example, the base member 20 includes a support substrate 22 and a lens-carrying substrate 24 disposed on the inner surface of the support substrate 22. The lens-carrying substrate 24 is fixed to a predetermined position on the support substrate 22 by, for example, an adhesive. However, the lens-carrying substrate 24 is an optional component and may be omitted depending on the purpose.

[0022] The support base material 22 is made of, for example, a film base material having the same flexibility as the film base material that constitutes the lid member 10 .

[0023] The lens-loading substrate 24 in the illustrated example has a disk-shaped lens-loading portion 24a and an edge portion 24b surrounding the outer periphery of the lens-loading portion 24a and having a maximum height T2 that is greater than the maximum height T1 of the lens-loading portion 24a ( FIGS. 1D , 2 , and 4A ). In a sealed contact lens package, a contact lens is typically loaded on the lens-loading portion 24a of the lens-loading substrate 24. The lens-loading substrate 24 is formed from a resin material such as PE, PP, or PET, and has the mechanical strength and shape-retaining properties to support a contact lens.

[0024] The shape of the lens carrying substrate 24 is not limited to the illustrated example. For example, the lens carrying substrate may be non-circular (e.g., elliptical, polygonal, etc.). For example, the lens carrying portion may be flat, or may be curved upwardly convexly or concavely, depending on the purpose. Specifically, as shown in FIG. 4B , the lens carrying portion 24 a may be curved upwardly convexly. For example, the lens carrying substrate may not have an edge.

[0025] The thickness of the lens mounting portion 24a is, for example, 0.1 mm to 1.0 mm, and preferably 0.2 mm to 0.9 mm.

[0026] As shown in the illustrated example, the lens mounting base 24 may have a through-hole 24c that penetrates the lens mounting portion 24a in the thickness direction. One or more through-holes may be provided.

[0027] The storage space 110 sealed by the lid member 10 and the bottom member 20 can be formed by bonding the lid member 10 and the bottom member 20 (more specifically, the lid member 10 and the support substrate 22) together so as to surround a predetermined region. For example, a contact lens is placed at a predetermined position on the bottom member (e.g., on the lens-loading portion of the lens-loading substrate), and then the lid member and the bottom member are bonded together at least in a predetermined region surrounding the lens-loading substrate (e.g., region S in FIG. 2 ). This provides a contact lens package in which a contact lens is housed in a storage space sealed by the lid member and the bottom member. From the viewpoints of hermetic sealing and ease of opening, bonding is preferably performed by heat sealing or ultrasonic sealing, with heat sealing being more preferred. The contact lens package 200A shown in the figure has protruding portions on the top surface (lid member 10) and the bottom surface (bottom member 20) corresponding to the lens-loading substrate 24, but the contact lens package according to this embodiment is not limited to this configuration. For example, the contact lens package may have one surface having a convex portion corresponding to the contact lens or lens-carrying substrate 24, and the other surface being flat.

[0028] The height of the storage space 110 may correspond to the maximum thickness of the portion of the contact lens package 200A corresponding to the storage space 110 minus the total thickness of the cover member and the bottom member. Here, when the bottom member 20 includes a support substrate 22 and a lens loading substrate 24, the thickness of the bottom member 20 may be the sum of the thickness of the support substrate 22 and the maximum height T1 of the lens loading portion 24a.

[0029] The height (maximum height) of the storage space is typically smaller than the natural sagittal height of the contact lens, and may be, for example, 4.5 mm or less, preferably 3 mm or less, more preferably 2.5 mm or less, and may be 2 mm or less, 1.5 mm or less, 1.2 mm or less, 1 mm or less, or 0.9 mm or less. The height of the storage space is, for example, 0.2 mm or more, and may be 0.3 mm or more, 0.4 mm or more, 0.5 mm or more, 0.6 mm or more, 0.8 mm or more, 1 mm or more, 1.2 mm or more, 1.4 mm or more, 1.6 mm or more, 1.8 mm or more, or 2 mm or more. When the height of the storage space is within the above range, a good balance can be achieved between thinning the contact lens package and suppressing wrinkles on the lens, and as a result, the effects of the present invention can be preferably achieved. Packages having such a storage space height are not limited to the configuration of the illustrated example, and for example, those described in JP 2005-234576 A can also be used.

[0030] 5 is a schematic cross-sectional view showing the configuration of a contact lens package according to another embodiment of the present invention. The contact lens package 200B includes a package 100 having a cover member 10 and a base member 20, and a contact lens 120 accommodated in a storage space 110 sealed by the cover member 10 and the base member 20. Although not shown, a contact lens storage solution is also accommodated in the storage space 110, thereby maintaining the contact lens 120 in a hydrated state. The contact lens 120 is accommodated in the storage space 110 in a deformed state, specifically, with its height smaller than its natural sagittal height, and may be in a flattened state, for example.

[0031] The cover member 10 is made of, for example, a flexible film substrate. The material for forming the film substrate is the same as that described for the contact lens package 200A.

[0032] The base member 20 is typically relatively thick and has shape-retaining properties. As shown in Fig. 6, the base member 20 has a concave storage recess 26 for storing a contact lens and storage solution, and a flat flange portion 27 surrounding the storage recess 26. The storage recess 26 and the flange portion 27 are integrally molded by injection molding or the like using a synthetic resin such as polyethylene (PE), polypropylene (PP), or polyethylene terephthalate (PET). The thickness of the base member 20 can be, for example, 0.1 mm to 2 mm, and preferably 0.2 mm to 1 mm.

[0033] The lid member 10 is disposed so as to cover the upper surface of the bottom member 20 in a substantially flat manner. The lid member 10 is releasably joined to the bottom member 10 at least in an area surrounding the entire periphery of the accommodation recess 26, and is laminated on the bottom member 10 without being joined in at least one end area. The joining of the bottom member and the lid member can be performed by, for example, heat sealing, ultrasonic sealing, or the like.

[0034] The storage space 110 is a space defined by the storage recess 26 and the cover member 10. The height (maximum height) of the storage space is typically smaller than the natural sagittal height of the contact lens, and may be, for example, 4.5 mm or less, preferably 3 mm or less, more preferably 2.5 mm or less, and may be 2 mm or less or 1.5 mm or less. The height of the storage space is, for example, 0.2 mm or more, and may be 0.3 mm or more, 0.4 mm or more, 0.5 mm or more, 0.6 mm or more, 0.8 mm or more, 1 mm or more, 1.2 mm or more, 1.4 mm or more, 1.6 mm or more, 1.8 mm or more, or 2 mm or more. When the height of the storage space is within the above range, a good balance can be achieved between thinning the contact lens package and suppressing wrinkles in the lens, resulting in the advantageous achievement of the effects of the present invention.

[0035] 7 is a schematic cross-sectional view showing the configuration of a contact lens package according to yet another embodiment of the present invention. The contact lens package 200C includes a package 100 having a cover member 10 and a base member 20, and a contact lens 120 accommodated in a storage space 110 sealed by the cover member 10 and the base member 20. Although not shown, a contact lens storage solution is also accommodated in the storage space 110, thereby maintaining the contact lens 120 in a hydrated state.

[0036] 7 and 8 , the cover member 10 has a convex curved surface portion 12 that is generally circular in plan view and protrudes toward the bottom member 20, and a flat flange portion 14 that is provided to surround the convex curved surface portion 12; the bottom member 20 has a shape in plan view that corresponds to the convex curved surface portion 12, and has a concave curved surface portion 28 that protrudes toward the opposite side of the cover member 10, and a flat flange portion 27 that is provided to surround the concave curved surface portion 28; the cover member 10 and the bottom member 20 are positioned and joined so that the convex curved surface portion 12 and the concave curved surface portion 28 overlap, thereby forming a storage space 110. In the storage space 110, the contact lens 120 is typically positioned so that its inner surface faces the cover member 10.

[0037] As described above, the storage space 110 is defined by the convex curved surface portion 12 and the concave curved surface portion 28. Because such a storage space has a small volume, even if it has a shape that allows a contact lens to be stored therein while maintaining its natural sagittal height, the contact lens may be stuck to one of the components and deformed during autoclaving, etc., which may cause discomfort to the wearer in the early stages of wearing the contact lens. Therefore, the above-described contact lens package can suitably achieve the effects of the present invention.

[0038] The contact lens package 200C may be configured such that when the lid member 10 is peeled upward to open the package 100, the contact lens 120 adheres (is adsorbed) to the lid member 10. This configuration is not particularly limited, but for example, the concave curved surface portion 28 may have a radius of curvature (e.g., about 13 mm to about 19 mm) smaller than the radius of curvature of the convex curved surface portion 12, and the maximum separation distance between the concave curved surface portion 28 and the convex curved surface portion 12 may be less than 7 mm. Alternatively, the contact lens package 200C may be configured upside down, such that when the package 100 is opened by peeling upward the base member 20, the contact lens 120 adheres (is adsorbed) to the lid member 10 (in this case, the lid member 10 may function as the bottom member, and the base member 20 may function as the lid member). The volume of the storage space 110 may be, for example, 0.1 mL to 0.6 mL, preferably 0.2 mL to 0.5 mL, and more preferably 0.3 mL to 0.4 mL. The height of the storage space 110 (the maximum distance between the convex curved surface portion and the concave curved surface portion) may be, for example, 5 mm or less, preferably 1 mm to 3 mm. For details of a contact lens package having such a configuration, see JP-A-2023-532254, WO2013 / 153582, etc.

[0039] The contact lens 120 is typically a hydrogel contact lens (so-called soft contact lens). The Young's modulus of the contact lens obtained by a tensile test performed in an aqueous medium at 35°C is, for example, 1.6 MPa or less, preferably 1.2 MPa or less, 1.0 MPa or less, or 0.8 MPa or less. When the Young's modulus is within the above range, the lens is flexible and can suppress congestion and other problems that may occur due to friction between the lens and the ocular surface. Furthermore, the Young's modulus of the contact lens is, for example, 0.1 MPa or more, preferably 0.2 MPa or more, and may be, for example, 0.3 MPa or more, 0.4 MPa or more, or 0.5 MPa or more. When the Young's modulus is within the above range, problems such as the lens being too flexible and making it difficult to handle when wearing it (e.g., problems such as the lens sticking to fingers or being easily folded, requiring the lens to be adjusted to its shape when worn) can be resolved. Furthermore, when the Young's modulus is within the range from the lower limit to the upper limit, it is possible to solve the problem related to the flexibility of the lens and to suppress deformation (wrinkles) of the lens. As the aqueous medium, distilled water, physiological saline, etc. can be suitably used.

[0040] The relaxation modulus of a contact lens obtained in a stress relaxation test carried out in an aqueous medium at 35°C is, for example, 1.8 MPa or less, preferably 1.6 MPa or less, more preferably 1.5 MPa or less, even more preferably 1.4 MPa or less, even more preferably 1.3 MPa or less, even more preferably 1.2 MPa or less, even more preferably 1.1 MPa or less, and may be 0.9 MPa or less, 0.8 MPa or less, 0.7 MPa or less, 0.6 MPa or less, or 0.5 MPa or less. The relaxation modulus may, for example, be 0.1 MPa or more, 0.2 MPa or more, or 0.3 MPa or more. Here, the relaxation modulus of the contact lens is the modulus measured 1 second after the start of measurement when a contact lens piece is subjected to a strain of 75% of the upper limit of the linear elastic region in a tensile test in an aqueous medium at 35°C and the stress required to hold the contact lens piece is simultaneously measured. A relaxation modulus within the above range can improve the discomfort of vision during the initial wearing of a contact lens taken out of a contact lens package. The reason for this effect, without limiting the present invention, is presumed to be as follows. Specifically, because the contact lens is stored in a deformed state (e.g., flat) in the storage space, minute deformations (wrinkles) may be present on the surface of the contact lens immediately after removal from the contact lens package. While these wrinkles can cause uneven power on the contact lens surface, leading to the aforementioned discomfort in vision, contact lenses having the above-mentioned relaxation modulus are presumed to facilitate the elimination of deformations (wrinkles) over time, thereby quickly relieving the discomfort in vision during initial wear. This effect can be more effectively achieved when contact lenses having the above-mentioned relaxation modulus are used. For example, when the relaxation modulus is 1.6 MPa or less, the discomfort in vision during initial wear can be effectively resolved even when the tensile loss tangent (described later) exceeds 0.1.

[0041] The tensile loss tangent (tanδ) of the contact lens obtained by dynamic tensile viscoelasticity measurement performed in an aqueous medium at 35°C is, for example, 0.14 or less, preferably 0.1 or less, more preferably 0.09 or less, even more preferably 0.08 or less, even more preferably 0.07 or less, and even more preferably 0.06 or less, and may be 0.05 or less or 0.04 or less. The loss tangent (tanδ) may be, for example, 0.001 or more, 0.005 or more, or 0.01 or more. When tanδ is within the above range, the occurrence of wrinkles in the contact lens stored in a deformed state in the storage space tends to be suppressed, and as a result, it is presumed that discomfort in the initial period of wear can be reduced. Such an effect can be more preferably achieved by using a contact lens with a tanδ of 0.1 or less. For example, when tanδ is 0.1 or less, discomfort in the initial period of wear can be preferably eliminated even when the relaxation modulus exceeds 1.6 MPa.

[0042] In one embodiment, the contact lens has a relaxation modulus of 1.6 MPa or less and a tan δ of 0.1 or less. Such a contact lens can suitably prevent wrinkles from forming while it is stored in a storage space in a deformed state, and can quickly eliminate any wrinkles that may occur after the contact lens is removed from the package, thereby more suitably eliminating discomfort to vision during the initial period of wearing the contact lens.

[0043] The resilience (@100%) of a contact lens obtained in a recovery evaluation test conducted in an aqueous medium at 35°C is, for example, 85% or more, preferably 90% or more, and more preferably 92% to 100%. The resilience (@100%) is the ratio of the energy released to shrink the contact lens from a stretched state to a stretching ratio of 0% (original length) to the energy absorbed when the contact lens is stretched at a stretching ratio of 100% (twice the original length). When the resilience (@100%) is within the above range, the occurrence of wrinkles in a contact lens stored in a deformed state in a storage space tends to be suppressed, and as a result, it is presumed that visual discomfort during initial wear can be reduced. Such an effect can be preferably achieved by using a contact lens with a resilience (@100%) of 90% or more. For example, when the resilience (@100%) is 90% or more, visual discomfort during initial wear can be preferably eliminated even when the relaxation modulus exceeds 1.7 MPa.

[0044] The water content of the contact lens is, for example, 10% to 90%, or, for example, 20% to 80%, and may be 30% or more, 35% or more, 40% or more, 45% or more, or 50% or more. When the water content is within the above range, the contact lens can function as a hydrogel contact lens with high flexibility and excellent wearing comfort. Furthermore, by changing the water content, it is possible to adjust the physical properties of the contact lens, such as the relaxed modulus, tan δ, and resilience, thereby suppressing the occurrence of wrinkles in the contact lens and, if wrinkles do occur, effectively eliminating them. The water content can be measured, for example, by the method described in ISO 18369-4.

[0045] From the viewpoint of both suppressing or eliminating deformation (wrinkles) and achieving oxygen permeability, the oxygen permeability coefficient (Dk: × 10 －１１ (cm ２ / sec)・(mLO ２ / mL·mmHg)) is, for example, 12 or more, preferably 24 or more, more preferably 30 or more, even more preferably 36 or more, even more preferably 48 or more, and even more preferably 60 or more, and may be, for example, 140 or less, 130 or less, 120 or less, 110 or less, or 100 or less. The oxygen permeability coefficient is a value calculated in accordance with ISO 18369-4. From the viewpoint of both suppressing or eliminating deformation (wrinkles) and achieving oxygen permeability, the oxygen permeability coefficient (oxygen permeability) per unit thickness of the contact lens (Dk / t: × 10 －９ (cm·mLO ２ / sec·mL·mmHg)) is, for example, 12 or more, preferably 24 or more, more preferably 36 or more, even more preferably 40 or more, even more preferably 48 or more, and even more preferably 60 or more, and may be, for example, 170 or less, 150 or less, 140 or less, 130 or less, 120 or less, 110 or less, or 100 or less. The oxygen permeability (Dk / t) of a contact lens can be calculated by dividing the oxygen permeability coefficient (Dk) by the center thickness (cm) of the lens.

[0046] A contact lens is made of any suitable polymer material that can satisfy the above-mentioned properties. The polymer material that makes up the contact lens is obtained by polymerizing a polymerizable composition containing monomer components, and contains structural units derived from each monomer in the monomer components. In this specification, the content ratio of the structural units derived from each monomer in the polymer material is considered to correspond to the blending ratio of each monomer in the monomer components.

[0047] The monomer component typically contains a hydrophilic monomer and a crosslinking monomer. The monomer component may further contain a hydrophobic monomer and / or a siloxane monomer, as needed. By using a monomer component containing a siloxane monomer, a silicone hydrogel contact lens can be obtained.

[0048] As the hydrophilic monomer, a monofunctional monomer having a polar group (excluding those having a siloxane bond), such as a hydroxyl group-containing monomer, a carboxyl group-containing monomer, a nitrogen atom-containing monomer, or an alkoxyl group-containing monomer, can be preferably used. By including a hydrophilic monomer in the monomer component, a polymer material having desired physical properties (flexibility, relaxation modulus, tan δ, etc.), water content, etc. can be suitably obtained. The hydrophilic monomer can be used alone or in combination of two or more. The solubility of the hydrophilic monomer in water at 25°C can be, for example, 0.03 g / mL or more.

[0049] Preferred examples of hydroxyl group-containing monomers include hydroxyl group-containing alkyl (meth)acrylates. Specific examples include hydroxyl group-containing alkyl (meth)acrylates in which the alkyl group has 1 to 4 carbon atoms, such as hydroxymethyl (meth)acrylate, hydroxyethyl (meth)acrylate, hydroxypropyl (meth)acrylate, hydroxybutyl (meth)acrylate, dihydroxyethyl (meth)acrylate, dihydroxypropyl (meth)acrylate, and dihydroxybutyl (meth)acrylate, and glyceryl (meth)acrylate. Examples of carboxyl group-containing monomers include (meth)acrylic acid, itaconic acid, maleic acid, fumaric acid, and crotonic acid, and acid anhydrides of these acids can also be preferably used. Examples of nitrogen atom-containing monomers include (meth)acrylamides such as N,N-dimethyl(meth)acrylamide, N-ethyl(meth)acrylamide, N-2-hydroxyethyl(meth)acrylamide, and N-isopropyl(meth)acrylamide; N-vinyllactams such as N-vinylpyrrolidone, N-vinylpiperidone, and N-vinylcaprolactam; N-methyllactams such as 1-methyl-3-methylene-2-pyrrolidinone; (meth)acrylonitrile; and N-(meth)acryloylmorpholine. Preferred examples of alkoxyl group-containing monomers include alkoxyalkyl(meth)acrylates. Specific examples include alkoxyalkyl(meth)acrylates in which the alkoxyalkyl group has 2 to 4 carbon atoms, such as methoxymethyl(meth)acrylate, methoxyethyl(meth)acrylate, ethoxymethyl(meth)acrylate, and ethoxyethyl(meth)acrylate.

[0050] The crosslinkable monomer may be a polyfunctional monomer having two or more polymerizable groups (excluding those having a siloxane bond). By including a crosslinkable monomer in the monomer component, a polymer material having desired physical properties (flexibility, mechanical strength, relaxation modulus, tan δ, etc.) can be suitably obtained. Specific examples of crosslinkable monomers include butanediol di(meth)acrylate, ethylene glycol di(meth)acrylate, diethylene glycol di(meth)acrylate, triethylene glycol di(meth)acrylate, propylene glycol di(meth)acrylate, dipropylene glycol di(meth)acrylate, diallyl fumarate, allyl (meth)acrylate, vinyl (meth)acrylate, trimethylolpropane tri(meth)acrylate, methacryloyloxyethyl (meth)acrylate, divinylbenzene, diallyl phthalate, diallyl adipate, triallyl diisocyanate, α-methylene-N-vinylpyrrolidone, 4-vinylbenzyl (meth)acrylate, 3-vinyl Examples of suitable diols include 1,4-bis(2-(meth)acryloyloxyphenyl)hexafluoropropane, 2,2-bis((meth)acryloyloxyphenyl)propane, 1,4-bis(2-(meth)acryloyloxyhexafluoroisopropyl)benzene, 1,3-bis(2-(meth)acryloyloxyhexafluoroisopropyl)benzene, 1,2-bis(2-(meth)acryloyloxyhexafluoroisopropyl)benzene, 1,4-bis(2-(meth)acryloyloxyisopropyl)benzene, 1,3-bis(2-(meth)acryloyloxyisopropyl)benzene, and 1,2-bis(2-(meth)acryloyloxyisopropyl)benzene. Among these, butanediol di(meth)acrylate and ethylene glycol di(meth)acrylate are preferred because of their excellent copolymerizability and the ease with which the flexibility and mechanical strength of the polymer material can be adjusted. The crosslinkable monomers may be used alone or in combination of two or more.

[0051] As the hydrophobic monomer, monofunctional monomers without polar groups (excluding those with siloxane bonds), such as alkyl (meth)acrylates, fluorine-containing alkyl (meth)acrylates, aromatic ring-containing (meth)acrylates, and styrene-based monomers, can be preferably used. By including a hydrophobic monomer in the monomer component, a polymer material with desired mechanical strength, water content, etc. can be suitably obtained. The hydrophobic monomer can be used alone or in combination of two or more. The solubility of the hydrophobic monomer in water at 25°C can be, for example, less than 0.03 g / mL.

[0052] Preferred examples of alkyl(meth)acrylates include alkyl(meth)acrylates in which the alkyl group has 1 to 20 carbon atoms. Specific examples include linear, branched, or cyclic alkyl(meth)acrylates such as methyl(meth)acrylate, ethyl(meth)acrylate, propyl(meth)acrylate, butyl(meth)acrylate, pentyl(meth)acrylate, hexyl(meth)acrylate, heptyl(meth)acrylate, nonyl(meth)acrylate, stearyl(meth)acrylate, octyl(meth)acrylate, decyl(meth)acrylate, lauryl(meth)acrylate, pentadecyl(meth)acrylate, 2-ethylhexyl(meth)acrylate, cyclopentyl(meth)acrylate, and cyclohexyl(meth)acrylate. Of these, alkyl(meth)acrylates in which the alkyl group has 1 to 5 carbon atoms are preferred. Although methyl acrylate has a solubility in water at 25°C of more than 0.03 g / mL, it is treated as a hydrophobic monomer in this specification because it does not have a polar group. Examples of fluorine-containing alkyl (meth)acrylates include those in which fluorine has been introduced into the alkyl group of the above alkyl (meth)acrylates. Specific examples include 2,2,2-trifluoroethyl (meth)acrylate, 2,2,3,3-tetrafluoropropyl (meth)acrylate, 2,2,3,3-tetrafluoro-t-pentyl (meth)acrylate, 2,2,3,4,4,4-hexafluorobutyl (meth)acrylate, 2,2,3,4,4,4-hexafluoro-t-hexyl (meth)acrylate, and 2,3,4,5,5,5-hexafluoro. 2,4-bis(trifluoromethyl)pentyl (meth)acrylate, 2,2,3,3,4,4-hexafluorobutyl (meth)acrylate, 2,2,2,2',2',2'-hexafluoroisopropyl (meth)acrylate, 2,2,3,3,4,4,4-heptafluorobutyl (meth)acrylate, 2,2,3,3,4,4,5,5-octafluoropentyl (meth)acrylate, and the like.Examples of aromatic ring-containing (meth)acrylates include phenoxyethyl (meth)acrylate, phenylethyl (meth)acrylate, benzyl (meth)acrylate, phenyl (meth)acrylate, pentabromophenyl (meth)acrylate, etc. Examples of styrene-based monomers include styrene, α-methylstyrene, methylstyrene, ethylstyrene, acetoxystyrene, methoxystyrene, ethoxystyrene, propoxystyrene, butoxystyrene, etc.

[0053] Any appropriate monomer can be used as the siloxane monomer, as long as it has a siloxane bond (Si—O—Si) and a polymerizable group. By including a siloxane monomer in the monomer component, a polymer material with high oxygen permeability can be suitably obtained. The number of siloxane bonds in the siloxane monomer is, for example, 1 to 100, and can be 2 to 20, 2 to 10, or 2 to 5. The number of siloxane bonds does not refer to the number of repeating siloxane bonds in one chain, but refers to the total number of all siloxane bonds in the monomer molecule. The number of polymerizable groups in the siloxane monomer may be one or two or more. A single siloxane monomer can be used alone, or two or more types can be used in combination.

[0054] Examples of the siloxane monomer include monomers conventionally used for ophthalmic devices, such as the siloxane monomers described in paragraphs 0039 to 0044 of JP-T-2015-503631A, the siloxane monomers described in paragraphs 0060 to 0065 of JP-A-2014-40598A, and the siloxane monomers described in paragraphs 0024 to 0037 of WO-2015 / 92858A.

[0055] Other specific examples of siloxane monomers include trimethylsiloxydimethylsilylmethyl (meth)acrylate, trimethylsiloxydimethylsilylpropyl (meth)acrylate, methylbis(trimethylsiloxy)silylpropyl (meth)acrylate, tris(trimethylsiloxy)silylpropyl (meth)acrylate, mono[methylbis(trimethylsiloxy)siloxy]bis(trimethylsiloxy)silylpropyl (meth)acrylate, tris[methylbis(trimethylsiloxy)siloxy]silylpropyl (meth)acrylate, methylbis(trimethylsiloxy)silylpropyl glyceryl (meth)acrylate, tris(trimethylsiloxy)silylpropyl glyceryl (meth)acrylate, mono[methylbis(trimethylsiloxy)siloxy]bis(trimethylsiloxy)silylpropyl siloxane-containing alkyl (meth)acrylates such as trimethylsiloxy)silylpropyl glyceryl (meth)acrylate, trimethylsilylethyl tetramethyldisiloxypropyl glyceryl (meth)acrylate, trimethylsilylmethyl (meth)acrylate, trimethylsilylpropyl glyceryl (meth)acrylate, trimethylsilylpropyl (meth)acrylate, trimethylsiloxydimethylsilylpropyl glyceryl (meth)acrylate, methylbis(trimethylsiloxy)silylethyl tetramethyldisiloxymethyl (meth)acrylate, tetramethyltriisopropylcyclotetrasiloxanylpropyl (meth)acrylate, and tetramethyltriisopropylcyclotetrasiloxybis(trimethylsiloxy)silylpropyl (meth)acrylate;Tris(trimethylsiloxy)silylstyrene, bis(trimethylsiloxy)methylsilylstyrene, (trimethylsiloxy)dimethylsilylstyrene, tris(trimethylsiloxy)siloxydimethylsilylstyrene, [bis(trimethylsiloxy)methylsiloxy]dimethylsilylstyrene, (trimethylsiloxy)dimethylsilylstyrene, heptamethyltrisiloxanylstyrene, nonamethyltetrasiloxanylstyrene, pentadecamethylheptasiloxanylstyrene, heptamethyldecasiloxanylstyrene Nylstyrene, heptacosamethyltridecasiloxanylstyrene, heptatriacontamethylpentadecasiloxanylstyrene, trimethylsiloxypentamethyldisiloxymethylsilylstyrene, tris(pentamethyldisiloxy)silylstyrene, tris(trimethylsiloxy)siloxybis(trimethylsiloxy)silylstyrene, bis(heptamethyltrisiloxy)methylsilylstyrene, tris[methylbis(trimethylsiloxy)siloxy]silylstyrene, heptakis(trimethylsiloxy)trisilyl silylstyrene, trimethylsiloxybis[tris(trimethylsiloxy)siloxy]silylstyrene, nonamethyltetrasiloxyundecylmethylpentasiloxymethylsilylstyrene, tris[tris(trimethylsiloxy)siloxy]silylstyrene, (tristrimethylsiloxyhexamethyl)tetrasiloxy[tris(trimethylsiloxy)siloxy]trimethylsiloxysilylstyrene, nonakis(trimethylsiloxy)tetrasilylstyrene, bis(tridecamethylhexasiloxy)methylsilylstyrene Examples of suitable styrene derivatives include siloxane-containing styrene derivatives such as styrene, heptamethylcyclotetrasiloxanylstyrene, heptamethylcyclotetrasiloxybis(trimethylsiloxy)silylstyrene, tripropyltetramethylcyclotetrasiloxanylstyrene, and trimethylsilylstyrene; and siloxane-containing fumaric acid diesters such as bis(3-(trimethylsilyl)propyl)fumarate, bis(3-(pentamethyldisiloxanyl)propyl)fumarate, and bis(tris(trimethylsiloxy)silylpropyl)fumarate. Among these, siloxane-containing styrene derivatives are preferred because they tend to achieve both high oxygen permeability and hardness.

[0056] Further specific examples of the siloxane monomer include mono(meth)acryloyloxypropyl-terminated, mono-n-butyl-terminated polydimethylsiloxane, mono(meth)acryloyloxypropyl-terminated, mono-n-methyl-terminated polydimethylsiloxane, mono(meth)acryloyloxypropyl-terminated, mono-n-butyl-terminated polydiethylsiloxane, mono(meth)acryloyloxypropyl-terminated, mono-n-methyl-terminated polydiethylsiloxane, mono(meth)acryloylaminopropyl-terminated, mono-n-butyl-terminated polydimethylsiloxane, mono(meth)acryloylaminopropyl-terminated, mono-n-methyl-terminated polydimethylsiloxane, mono(meth)acryloylaminopropyl-terminated, mono-n-butyl-terminated polydiethylsiloxane, and mono(meth)acryloylaminopropyl-terminated, mono-n-methyl-terminated polydiethylsiloxane. In these siloxane monomers, the number of repeating (Si—O) groups may be, for example, 4 to 20, preferably 4 to 12, and more preferably 4 to 10.

[0057] The blending ratio of the hydrophilic monomer in the monomer components excluding the crosslinkable monomer is, for example, 30% by weight or more, 40% by weight or more, preferably 50% by weight or more, more preferably 60% by weight or more, and may be, for example, 100% by weight or less, or, for example, 95% by weight or less, 90% by weight or less.

[0058] The blending ratio of the hydrophobic monomer in the monomer components excluding the crosslinkable monomer is, for example, 5% by weight or less, preferably 3% by weight or less, and may be 0% by weight to 1% by weight.

[0059] The proportion of the siloxane monomer in the monomer components excluding the crosslinkable monomer is, for example, 60% by weight or less, preferably 50% by weight or less, more preferably 40% by weight or less, and may be 30% by weight or less, 20% by weight or less, or 15% by weight or less. The lower limit of the proportion of the siloxane monomer may be 0% by weight or more, 3% by weight or more, or 5% by weight or more.

[0060] The blending ratio of the crosslinkable monomer in the monomer component is, for example, 0.05% by weight or more, or, for example, 0.1% by weight or more, and typically 10% by weight or less, for example, 3% by weight or less, preferably 1% by weight or less, and more preferably 0.8% by weight or less.

[0061] By changing the type and / or blending ratio of each of the above monomers, it is possible to adjust the physical properties of the contact lens, such as mechanical strength, water content, relaxation modulus, tan δ, and resilience. Although the physical properties of the resulting polymer may vary depending on the type of monomer, etc., by increasing the blending ratio of the hydrophilic monomer and decreasing the blending ratio of the hydrophobic monomer, it is possible to obtain a contact lens having physical properties such as mechanical strength, water content, relaxation modulus, tan δ, and resilience within the desired range. For example, by increasing the blending ratio of the hydrophilic monomer and / or decreasing the blending ratio of the hydrophobic monomer, the mechanical strength, relaxation modulus, and tan δ can be reduced, and the water content and resilience can be increased. Furthermore, while a high blending ratio of the siloxane monomer can improve oxygen permeability, the deformation tends to remain as wrinkles in the deformed contact lens. Therefore, by including the siloxane monomer in the above-mentioned blending ratio, it is possible to achieve the desired relaxation modulus, tan δ, resilience, etc. while ensuring favorable oxygen permeability, thereby suppressing the occurrence of wrinkles or quickly eliminating wrinkles, and as a result, it is possible to preferably obtain a contact lens package that is excellent in wearing comfort and has improved difficulty in seeing during the initial period of wearing.

[0062] The monomer component may further include a functional monomer. Examples of the functional monomer include a polymerizable UV absorber, a polymerizable dye, and a polymerizable UV-absorbing dye. Specific examples of these include

[0087] to

[0089] of WO 2022 / 044117. Various functional monomers are commercially available, and a suitable monomer can be selected from these depending on the intended purpose. The functional monomer is a monomer that imparts a specific function to the resulting polymer, and is not included in the hydrophobic monomer, hydrophilic monomer, crosslinkable monomer, and siloxane monomer.

[0063] The total blending ratio of the functional monomers in the monomer component is, for example, 5% by weight or less, preferably 0.0001% by weight to 5% by weight, and more preferably 0.05% by weight to 3% by weight.

[0064] The polymerizable composition typically contains a polymerization initiator in addition to the above-mentioned monomer components, and may further contain a solvent and / or additives, as necessary, such as a cooling agent, a thickener, a surfactant, a non-polymerizable dye, and a non-polymerizable ultraviolet absorber.

[0065] The amount of the additives in the polymerizable composition can be, for example, 0.01 to 5 parts by weight, preferably 0.01 to 3 parts by weight, per 100 parts by weight of the monomer component.

[0066] As the polymerization method, photopolymerization, thermal polymerization, and a combination thereof can be applied.

[0067] When polymerizing a polymerizable composition by photopolymerization, it is preferable to fill or coat a mold with the polymerizable composition and then irradiate the mold with light (e.g., ultraviolet light). Specifically, contact lenses can be manufactured by any manufacturing method, such as a cast molding method or a spin casting method. The material of the mold used for photopolymerization is not particularly limited as long as it is a material that can transmit the light necessary for polymerization. The wavelength of the light irradiated onto the polymerizable composition in the mold is appropriately set depending on the type of photopolymerization initiator used, etc. Furthermore, the light illuminance and irradiation time can be appropriately set depending on the composition of the polymerizable composition, etc.

[0068] When the polymerizable composition is polymerized by thermal polymerization, it is preferable to gradually heat the mold after filling or applying the polymerizable composition into the mold. The heating temperature and heating time when heating the polymerizable composition in the mold can be appropriately set depending on the composition of the polymerizable composition, etc.

[0069] After polymerization, the polymer material is removed from the mold to obtain a contact lens. If necessary, the resulting contact lens may be immersed in water, an organic solvent, or a mixture thereof to elute unreacted monomer components, solvent, and other residues. The residue elution treatment may be repeated. The resulting contact lens may also be subjected to a surface treatment such as plasma treatment.

[0070] As described above, a contact lens package can be obtained by bonding the lid member and the base member together at least in a predetermined region surrounding the contact lens, with the contact lens placed in a predetermined position on the base member (e.g., on the lens loading section or the receiving recess). The lid member and the base member can be bonded together by, for example, heat sealing or ultrasonic sealing. The contact lens package can be sterilized as needed. Sterilization can be performed by any suitable method, such as autoclaving (e.g., high-temperature steam sterilization) or gamma ray sterilization.

[0071] [Method for Improving Wrinkle Recovery and Method for Suppressing Wrinkle Formation] As described above, when a contact lens having a low relaxation modulus is used, even if the contact lens is deformed (wrinkled) due to being stored in a deformed state in a sealed storage space, the wrinkles tend to disappear over time after opening, and therefore discomfort in the initial stage of wear can be quickly alleviated. Therefore, according to another aspect of the present invention, there is provided a method for improving the wrinkle recovery of a contact lens when a contact lens package is opened, the method comprising: producing a contact lens package by joining a lid member and a base member facing each other so as to form a sealed storage space in which a contact lens is placed, the height of the storage space being smaller than the natural sagittal height of the contact lens, and the relaxation modulus of the contact lens being 1.6 MPa or less.

[0072] As described above, a contact lens having a small tan δ or a large resilience can suppress the occurrence of wrinkles while the contact lens is stored in a sealed storage space in a deformed state, thereby reducing discomfort in the initial period of wear. Therefore, according to another aspect of the present invention, there is provided a method for suppressing the occurrence of wrinkles in a contact lens in a contact lens package, the method comprising: producing a contact lens package by joining a lid member and a base member facing each other so as to form a sealed storage space in which a contact lens is placed, the height of the storage space being smaller than the natural sagittal height of the contact lens, and the method satisfies at least one of the following: (i) the tensile loss tangent of the contact lens, as determined by dynamic tensile viscoelasticity measurement in an aqueous medium at 35°C, is 0.1 or less; and (ii) the ratio of the energy released to shrink the contact lens from a stretched state to a stretched state of 0% to the energy absorbed when the contact lens is stretched at a stretch ratio of 100% in an aqueous medium at 35°C is 90% or more.

[0073] The present invention will be described in more detail below with reference to examples, but the present invention is not limited to these examples. Unless otherwise specified, "parts" and "%" in the examples and comparative examples are by weight.

[0074] [Experimental Example 1-7] A lid member and a bottom member were prepared as shown in Figures 1A to 1D. Specifically, the lid member was made of a flexible aluminum-deposited PP film. The bottom member was made of a support substrate made of a flexible aluminum-deposited PP film and a lens-loading substrate fixed to the aluminum-deposited surface with an adhesive. The lens-loading substrate was made of PP and had a disk-shaped lens-loading portion with a through-hole and a rim formed on its outer periphery. Contact lenses obtained by polymerizing the monomer components shown in Table 1 were used. A dropper's worth of saline was added to the lens-loading portion of the support substrate, and various contact lenses were placed on top of it with their inner surfaces facing downward. Another dropper's worth of saline was added on top of them. Next, the lid member was placed over the lens-loading substrate and contact lens, and the periphery of the lens-loading substrate was heat-sealed with the outer edges of the lid member and the bottom member aligned. This resulted in a contact lens package in which the contact lens was sealed in a flattened state in the storage space between the lid member and the bottom member. The top surface of the contact lens package was flat, and the storage space had a height of 1 mm. The contact lens package was then autoclaved using a small retort autoclave. The sterilization temperature was 121°C, the sterilization pressure was 0.20 MPa, and the sterilization time was 20 minutes. In Table 1, the center thickness of the contact lens is the average value of the center thicknesses of three hydrated contact lenses.

[0075] [Evaluation of Physical Properties of Contact Lenses] <Preparation of Measurement Samples> A contact lens was removed from the autoclaved contact lens package and cut using a processing jig with four razor blades arranged in parallel at 2 mm intervals. As a result, three strip-shaped contact lens pieces were prepared from one contact lens, as shown in Figure 9. The contact lens piece passing through the center of the lens (C in Figure 9) was used as the measurement sample, and a tensile measurement test, a dynamic tensile viscoelasticity measurement test, a resilience evaluation test, and measurement of the oxygen permeability coefficient (Dk value) were performed. A peripheral contact lens piece (S1 or S2 in Figure 9) was used as the measurement sample, and a stress relaxation test was performed.

[0076] <Tensile Test> In a tensile test in which a measurement sample was pulled at a constant speed, a stress-strain curve was obtained from the raw data of extension distance vs. detected load. Young's modulus was calculated from the initial slope of the stress-strain curve (strain range = 0 to 10%), and an average value of n = 3 was obtained. The measurement conditions were as follows: - Measurement equipment: Viscoelasticity measuring device "RSA3" (manufactured by TA Instruments) - Measurement environment: Distilled water at 35°C (physiological saline at 35°C for Experimental Examples 1 and 2) - Number of measurement samples: n = 3 - Measurement mode: Transient - Measurement item name: Multiple Extension Mode Test - Pulling speed: 0.01 mm / sec, 140 seconds (data acquisition 140 points, extension 1.4 mm) - Young's modulus calculation: Strain range 0 to 10%

[0077] <Stress Relaxation Test> A strain (initial strain) of 75% relative to the upper limit of the linear elastic region in the tensile test was applied to the measurement sample, and simultaneously measurement of the change in stress (relaxation) required to hold the measurement sample with the initial strain applied was started. The elastic modulus (stress / strain) 1 second after the start of measurement was calculated as the relaxation modulus (MPa), and the average value of n = 3 was obtained. The measurement conditions were as follows: - Measurement equipment: Viscoelasticity measuring device "RSA3" (manufactured by TA Instruments) - Measurement environment: Distilled water at 35°C (physiological saline at 35°C for Experimental Examples 1 and 2) - Number of measurement samples: n = 3 - Measurement mode: Transient - Measurement item name: Stress Relaxation - Initial strain: A strain of 75% relative to the upper limit of the linear elastic region in the tensile test.

[0078] <Dynamic tensile viscoelasticity measurement test> The elastic component (E') and viscous component (E'') of the sample were calculated from the response when an extension strain was applied to the measurement sample while maintaining a constant tension state. Next, the tensile loss tangent (tan δ) was calculated from E'' / E' at 1.0 Hz, and an average value of n=3 was obtained. The measurement conditions were as follows: - Measuring equipment: Viscoelasticity measuring device "RSA3" (manufactured by TA Instruments) - Measurement environment: Distilled water at 35°C (physiological saline at 35°C for Experimental Examples 1 and 2) - Number of measured samples: n = 3 - Measurement mode: Dynamic - Measurement item name: Dynamic Frequency Sweep Test - Measurement frequency: 0.628 rad / sec (= 0.1 Hz) to 62.8 rad / sec (= 10 Hz) - Initial applied load (Initial Static Force): The load equivalent to 75% of the linear elastic region was calculated from the Young's modulus and the cross-sectional area of ​​the sample. - Dynamic strain: 2.5%

[0079] <Resilience Evaluation Test> A sample was stretched at a constant stretching rate and then shrunk to its original size. This stretch-shrinkage measurement was repeated at different stretching ratios to obtain stress-strain curves at multiple stretching ratios. The measurement conditions were as follows: Resilience was calculated using the formula: [Resilience (%) = Area under the "stress-strain curve" during shrinkage / Area under the "stress-strain curve" during stretching × 100], and the average resilience (n = 3) at a stretching ratio of 100% was obtained. Measurement equipment: Viscoelasticity measuring device "RSA3" (manufactured by TA Instruments) Measurement environment: distilled water at 35°C (physiological saline at 35°C for Experimental Examples 1 and 2) Number of measured samples: n = 3 Measurement mode: Transient Measurement item name: Multiple Extension Mode Test Stretching speed: 0.1 mm / sec Stretching ratio: Approximately 25% → 50% → 75% → 100% → 125% → 150% (end)

[0080] <Measurement of Oxygen Permeability Coefficient (Dk Value)> The oxygen permeability coefficient was calculated in accordance with ISO 18369-4.

[0081] <Measurement of Moisture Content> The moisture content was measured in accordance with ISO 18369-4.

[0082] [Power Distribution Evaluation Test] For contact lenses removed from the contact lens packages produced in the experimental examples, the Q values ​​were measured 15 seconds and 900 seconds after opening under the following measurement conditions, and an average value of n=3 was obtained. The Q value is a quality factor proportional to the amount of wavefront deformation in power units in the analyzed region of the lens, and is a value indicating the standard deviation of the power distribution in that region. A small Q value means that the power unevenness on the lens surface is small. For example, Figure 10 (a) shows the power distribution of a contact lens in which the Q values ​​of all ring regions are 2 or more, while (b) shows the power distribution of a contact lens in which the Q values ​​of all ring regions are 2 or less, and it can be seen that the contact lens in (b) has smaller power unevenness than the contact lens in (a).・Measurement equipment: Underwater power measurement device "VC-2001" (manufactured by Visionix) ・Measurement temperature: Approximately 20 to 25°C (room temperature controlled) ・Environmental solution (solution in which the lens is immersed during measurement): Phosphate buffered saline ・Area to be analyzed: Ring area with a radius of 1.5 mm to 5.0 mm from the center of the lens in a planar view (specifically, ring area with a radius of 1.5 mm to 2.0 mm, ring area with a radius of 2.0 mm to 2.5 mm, ring area with a radius of 2.5 mm to 3.0 mm, ring area with a radius of 3.0 mm to 4.0 mm, ring area with a radius of 4.0 mm to 5.0 mm ・Number of measurements: 3 / sample

[0083]

[0084] As shown in Table 1, contact lenses with a tan δ of 0.1 or less achieved a Q value of 2 or less in a ring region with a radius of 1.5 mm to 2.5 mm 15 seconds after removal from the thin package (Experimental Examples 1-3 and 5). In particular, the contact lenses of Experimental Examples 3 and 5, which were prepared using a siloxane monomer, had ring regions with a Q value of more than 1 after 15 seconds, whereas the contact lenses of Experimental Examples 1 and 2, which were prepared without a siloxane monomer, had a Q value of 1 or less after 15 seconds over the entire ring region. Furthermore, contact lenses with a relaxation modulus after 1 second of 1.6 MPa or less achieved a Q value of 2 or less in a ring region with a radius of 1.5 mm to 2.5 mm and a Q value of 3 or less over the entire ring region with a radius of 1.5 mm to 5.0 mm 900 seconds after removal from the thin package, even when the contact lenses had a tan δ of more than 0.1 (Experimental Example 4). From the above, it can be seen that by storing a contact lens with a low tan δ (e.g., tan δ≦0.1) in a thin package, the occurrence of wrinkles (deformation) in the contact lens while it is stored in the storage space can be suppressed. It can also be seen that by storing a contact lens with a low relaxation modulus (e.g., relaxation modulus ≦1.6 MPa) in a thin package, the ability to eliminate (recover) wrinkles (deformation) in the contact lens after opening can be improved. Furthermore, as shown in the table below, contact lenses with a low relaxation modulus (e.g., relaxation modulus ≦1.6 MPa or ≦1.3 MPa) tended to have a high wrinkle recovery rate [Q value reduction rate = (1−Q value after 900 seconds / Q value after 15 seconds) × 100] between 15 seconds and 900 seconds. It can also be seen that contact lenses with high resilience (e.g., resilience ≧90%) can suppress the occurrence of wrinkles (deformation) in the contact lens while it is stored in the storage space.

[0085]

[0086] [Experimental Examples 8-10] Contact lens packages were prepared in the same manner as in Experimental Examples 1-7 above, using contact lenses prepared by polymerizing a polymerizable composition having the following composition. The power distribution of the resulting contact lens packages was evaluated in the same manner as in Experimental Example 1-7, except that the measurement area was a spot area within 3 mm from the center of the lens in a plan view. All of the results showed low Q values ​​equal to or lower than those of Experimental Examples 1-3. From this, it can be seen that the contact lens packages of Experimental Examples 8-10 improve the ability to eliminate (recover) wrinkles (deformations) in the contact lens after opening, or suppress the occurrence of wrinkles (deformations) in the contact lens while it is contained in the storage space, thereby improving the discomfort of vision in the initial period after wearing the contact lens, even when it is worn immediately after being taken out of the thin package.

[0087] The contact lens package according to the embodiment of the present invention can be suitably used in the manufacture and sale of contact lenses.

[0088] REFERENCE SIGNS LIST 10 Lid member 20 Bottom member 22 Support substrate 24 Lens-loading substrate 100 Package 110 Storage space 120 Contact lens 200 Contact lens package

Claims

1. A contact lens package comprising a package having a lid member and a bottom member, and a contact lens accommodated in a deformed state in an accommodation space sealed by the lid member and the bottom member, wherein the relaxation elastic modulus of the contact lens is 1.6 MPa or less, and the relaxation elastic modulus of the contact lens is the elastic modulus 1 second after the start of measurement when a strain of 75% with respect to the upper limit of the linear elastic region in a tensile test is applied to a contact lens piece in an aqueous medium at 35°C and at the same time the measurement of the stress required to hold the contact lens piece is started.

2. The contact lens package according to claim 1, wherein the loss tangent of the tensile force of the contact lens by dynamic tensile viscoelasticity measurement in an aqueous medium at 35°C is 0.14 or less.

3. The contact lens package according to claim 1, wherein the relaxation elastic modulus of the contact lens is 1.3 MPa or less.

4. A contact lens package comprising a package having a lid member and a bottom member, and a contact lens accommodated in a deformed state in an accommodation space sealed by the lid member and the bottom member, wherein the loss tangent of the tensile force of the contact lens by dynamic tensile viscoelasticity measurement in an aqueous medium at 35°C is 0.1 or less.

5. The contact lens package according to claim 4, wherein the loss tangent of the tensile force of the contact lens is 0.06 or less.

6. The contact lens package according to claim 4, wherein the relaxation elastic modulus of the contact lens is 1.8 MPa or less, and the relaxation elastic modulus of the contact lens is the elastic modulus 1 second after the start of measurement when a strain of 75% with respect to the upper limit of the linear elastic region in a tensile test is applied to a contact lens piece in an aqueous medium at 35°C and at the same time the measurement of the stress required to hold the contact lens piece is started.

7. A contact lens package including a package having a lid member and a bottom member, and a contact lens accommodated in a deformed state in an accommodation space sealed by the lid member and the bottom member, wherein the loss tangent of the tension of the contact lens by dynamic tensile viscoelasticity measurement in an aqueous medium at 35°C is 0.1 or less, the relaxation elastic modulus of the contact lens is 1.6 MPa or less, and the relaxation elastic modulus of the contact lens is the elastic modulus 1 second after the start of measurement when a strain of 75% with respect to the upper limit of the linear elastic region in a tensile test is applied to a contact lens piece in an aqueous medium at 35°C and at the same time the measurement of the stress required to hold the contact lens piece is started. Contact lens package.

8. The contact lens package according to claim 7, wherein the loss tangent of the tension of the contact lens is 0.06 or less.

9. The contact lens package according to claim 7, wherein the relaxation elastic modulus of the contact lens is 1.2 MPa or less.

10. The contact lens package according to claim 1, 4, or 7, wherein the oxygen permeability (Dk / t) of the contact lens is 24 or more.

11. The contact lens package according to claim 1, 4, or 7, wherein the contact lens is a silicone hydrogel lens.

12. The contact lens package according to claim 1, 4, or 7, wherein the contact lens is accommodated in the accommodation space in a state where its height is smaller than the natural sagittal height.

13. The contact lens package according to claim 1, 4, or 7, wherein the height of the accommodation space is 2 mm or less.

14. A method for improving the recoverability of wrinkles of a contact lens when a contact lens package is opened, the method including joining a lid member and a bottom member facing each other to form a sealed accommodation space in which the contact lens is disposed, the height of the accommodation space being smaller than the natural sagittal height of the contact lens, the relaxation elastic modulus of the contact lens being 1.6 MPa or less, and the relaxation elastic modulus of the contact lens being the elastic modulus 1 second after the start of measurement when a tensile test is started on a contact lens piece in an aqueous medium at 35° C. while applying a strain of 75% with respect to the upper limit of the linear elastic region.

15. A method for suppressing the occurrence of wrinkles of a contact lens in a contact lens package, the method including joining a lid member and a bottom member facing each other to form a sealed accommodation space in which the contact lens is disposed, the height of the accommodation space being smaller than the natural sagittal height of the contact lens, and satisfying at least one of the following (i) and (ii): (i) the loss tangent of the contact lens in a dynamic tensile viscoelasticity measurement in an aqueous medium at 35° C. is 0.1 or less; (ii) the ratio of the energy released to contract from the stretched state to a stretch ratio of 0% with respect to the energy absorbed when the contact lens is stretched at a stretch ratio of 100% in an aqueous medium at 35° C. is 90% or more.

16. A package having a lid member and a bottom member, and a contact lens accommodated in an accommodation space sealed by the lid member and the bottom member, wherein the accommodation space is defined by a convex curved surface portion protruding toward the bottom member side of the lid member and a concave curved surface portion protruding toward the side opposite to the lid member of the bottom member, and the contact lens is configured to adhere to the lid member or the bottom member when the package is opened, and satisfies at least one of the following (i) and (ii): (i) the relaxation elastic modulus of the contact lens is 1.6 MPa or less, and the relaxation elastic modulus of the contact lens is the elastic modulus 1 second after the start of measurement when a strain of 75% with respect to the upper limit of the linear elastic region in a tensile test is applied to a contact lens piece in an aqueous medium at 35° C. and at the same time the measurement of the stress required to hold the contact lens piece is started; (ii) the loss tangent of the tension of the contact lens by dynamic tensile viscoelasticity measurement in an aqueous medium at 35° C. is 0.1 or less; A contact lens package.

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