Optical member and method for manufacturing optical member

Abstract

An optical member (100) comprises: a first layer (11) that comprises a cured product of a first polymerizable composition; and a second layer (21) that is thicker than the thickness of the first layer (11), is provided in contact with the first layer (11), and comprises a cured product of a second polymerizable composition, wherein when, at an interface S (surface (11b), surface (21a)) between the first layer (11) and the second layer (21), the first layer (11) side is treated as peaks and the second layer (21) side is treated as valleys, the arithmetic mean height Sa as calculated according to ISO 4287-1997 is 0.01-0.15 μm, the maximum valley depth Sv is 0.2-2 μm, and the refractive index is 1.40-2.00.

Description

Optical member and method for manufacturing the same

[0001] The present invention relates to an optical member and a method for manufacturing an optical member.

[0002] It has been known that photochromic compounds have the property of being reversibly colored / decolored depending on the presence or absence of light such as sunlight. For example, eyeglasses using plastic lenses with photochromic properties function as normal clear eyeglasses indoors, but function like sunglasses outdoors by coloring the lenses gray, brown, etc. in response to sunlight (ultraviolet rays). While sunglasses require changing their appearance depending on whether they are indoors or outdoors, eyeglasses using photochromic lenses are highly convenient because they can be worn both indoors and outdoors as they are.

[0003] Methods for producing photochromic lenses include coating methods and lamination methods (cast polymerization methods).

[0004] For example, Patent Document 1 (WO 2011 / 125956) discloses a coating method for producing a photochromic lens by coating a plastic lens substrate to which no photochromic compound has been added with a coating liquid containing a photochromic compound.

[0005] Furthermore, Patent Document 2 (WO 2003 / 011967) discloses a cast polymerization method in which a gap is secured between a plastic lens and a glass mold, both are placed in a mold, a photochromic composition is poured into the gap, and the composition is polymerized and cured to form a photochromic layer on the surface of the plastic lens.

[0006] International Publication No. WO 2011 / 125956 International Publication No. WO 2003 / 011967

[0007] In conventional coating and lamination methods, a primer or adhesive is used to bond the lens substrate layer and the photochromic layer, but if a primer or adhesive is not used, peeling may occur between the lens substrate layer and the photochromic layer. Therefore, the techniques disclosed in Patent Documents 1 and 2 have room for improvement in terms of improving the adhesion between the layers.

[0008] Therefore, the present inventors conducted extensive research into improving interlayer adhesion in multilayer optical components and discovered that by controlling the roughness of the interlayer interface to fall within a predetermined numerical range, it is possible to improve interlayer adhesion while maintaining optical properties, thereby completing the present invention.

[0009] According to the present invention, the following optical member and method for manufacturing the optical member are provided.

[0010] [1] An optical element comprising: a first layer made of a cured product of a first polymerizable composition; and a second layer made of a cured product of a second polymerizable composition, the second layer being thicker than the first layer and provided in contact with the first layer; wherein, at the interface between the first layer and the second layer, when the first layer side is a peak and the second layer side is a valley, the optical element has an arithmetic mean height Sa of 0.01 to 0.15 μm and a maximum valley depth Sv of 0.20 to 2.00 μm, as determined in accordance with ISO 4287-1997; and a refractive index of 1.40 or more and 2.00 or less. [2] An optical member comprising: a first layer made of a cured product of a first polymerizable composition; and a second layer made of a cured product of a second polymerizable composition, the second layer having a thickness greater than that of the first layer and provided in contact with the first layer, wherein the interface between the first layer and the second layer has a center line average roughness Ra of 0.010 to 0.100 μm as measured in accordance with JIS B 0601-2001, with the first layer side being the peak and the second layer side being the valley, and a refractive index of 1.40 or more and 2.00 or less. [3] The optical member according to [1] or [2], wherein the first layer or the second layer comprises one or more resins selected from the group consisting of polycarbonate-based resins, (meth)acrylic-based resins, epoxy-based resins, urethane-based resins, episulfide-based resins, and thiourethane-based resins. [4] The optical member according to any one of [1] to [3], wherein the first polymerizable composition and the second polymerizable composition have different compositions. [5] The optical member according to any one of [1] to [4], wherein the second layer contains an episulfide-based resin. [6] The optical member according to any one of [1] to [5], wherein the first layer contains a dye. [7] The optical member according to any one of [1] to [6], wherein the first layer contains a photochromic dye. [8] The optical member according to any one of [1] to [7], wherein the first polymerizable composition contains a polyol compound. [9] The optical member according to [8], wherein the polyol compound contains one or more selected from linear or branched aliphatic polyols (i), alicyclic polyols (ii), and polyether polyols (iii).

[10] The optical member according to any one of [1] to [9], wherein the first layer has an average thickness of 0.1 mm to 5 mm.

[11] The optical member according to any one of [1] to

[10] , wherein the second layer has an average thickness of 0.5 mm to 20 mm.

[12] The optical member according to any one of [1] to

[11] , wherein the first layer has a refractive index of 1.50 to 1.67.

[13] The optical member according to any one of [1] to

[12] , wherein the absolute value of the difference between the refractive index of the first layer and the refractive index of the second layer is 0.45 or less.

[14] The optical member according to any one of [1] to

[13] , wherein the haze value according to JIS K7136 is 1% or more and 40% or less.

[15] The optical member according to any one of [1] to

[14] , wherein the light transmittance at a wavelength of 555 nm is 3 to 97%.

[16] An optical lens comprising the optical member described in any one of [1] to

[15] .

[17] A photochromic lens comprising the optical member described in any one of [1] to

[16] .

[18] A method for producing an optical member comprising: a first layer made of a cured product of a first polymerizable composition; and a second layer made of a cured product of a second polymerizable composition that is thicker than the first layer and is provided in contact with the first layer, the method comprising: curing the second polymerizable composition to form the second layer; polishing at least one surface of the second layer so that the arithmetic mean height Sa, as determined in accordance with ISO 4287-1997, is 0.01 to 0.15 μm and the maximum valley depth Sv is 0.20 to 2.00 μm; and forming the first layer made of the cured product of the first polymerizable composition on the polished surface of the second layer, wherein the refractive index of the optical member is 1.40 or more and 2.00 or less.

[19] The method for producing an optical member according to

[18] , wherein the first layer or the second layer contains one or more resins selected from the group consisting of polycarbonate-based resins, (meth)acrylic-based resins, epoxy-based resins, urethane-based resins, episulfide-based resins, and thiourethane-based resins.

[20] The method for producing an optical member according to any one of

[18] to

[19] , wherein the first polymerizable composition and the second polymerizable composition have different compositions.

[21] The method for producing an optical member according to any one of

[18] to

[20] , wherein the second layer contains an episulfide-based resin.

[22] The method for producing an optical member according to any one of

[18] to

[21] , wherein the polishing step uses an abrasive having an average particle size of 5 to 15 μm.

[23] The method for producing an optical member according to any one of

[18] to

[22] , wherein the polishing step uses an abrasive consisting of one or more types selected from alumina, diamond powder, boron nitride, cerium oxide, and zirconium oxide.

[24] The method for producing an optical member according to any one of

[18] to

[23] , comprising the step of cleaning the second layer after the polishing step and before the step of forming the first layer.

[25] The method for producing an optical member according to any one of

[18] to

[24] , wherein in the step of forming the first layer, a film made of a first polymerizable composition is laminated on the polished surface of the second layer and then cured, or the first polymerizable composition is injected into a mold in which the second layer has been placed and then cured to form the first layer.

[26] The method for producing an optical member according to any one of

[18] to

[25] , wherein the first polymerizable composition contains a photochromic dye.

[0011] The present invention can provide an optical member that maintains photochromic function while improving adhesion, and a method for manufacturing an optical member.

[0012] 1A to 1C are cross-sectional views schematically showing an optical member of the present embodiment, and FIG. 1B is a cross-sectional view schematically showing an example of a manufacturing process of the optical member of the present embodiment.

[0013] In this specification, the notation "a to b" in the description of a numerical range means from a to b, unless otherwise specified. For example, "1 to 5 mass %" means "1 mass % to 5 mass %." Furthermore, the lower limit and upper limit of a numerical range can be arbitrarily combined with the lower limit and upper limit of another numerical range.

[0014] Unless otherwise specified, each of the components and materials exemplified in this specification may be used alone or in combination of two or more.

[0015] In this specification, the term "(meth)acrylic" represents a concept that encompasses both acrylic and methacrylic. The same applies to similar terms such as "(meth)acrylate."

[0016] Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. To avoid complexity, when multiple identical components appear in the same drawing, only one of the components may be labeled with a reference symbol, and not all of the components may be labeled with a reference symbol. All drawings are for illustrative purposes only. The shapes and dimensional ratios of each component in the drawings do not necessarily correspond to actual objects.

[0017] In this embodiment, unless otherwise specified, the thickness refers to an average thickness. The thickness can be measured using a dial thickness gauge SM130 manufactured by TECLOCK Corporation.

[0018] 1 is a cross-sectional view schematically illustrating an optical member according to the present embodiment. The optical member 100 includes a first layer 11 made of a cured product of a first polymerizable composition, and a second layer 21 made of a cured product of a second polymerizable composition that is thicker than the first layer 11 and is provided in contact with the first layer 11. At an interface S (surface 11b, surface 21a) between the first layer 11 and the second layer 21, when the first layer 11 side is defined as a peak and the second layer 21 side is defined as a valley, the optical member 100 has an arithmetic mean height Sa of 0.01 to 0.15 μm, a maximum valley depth Sv of 0.20 to 2.00 μm, and a refractive index of 1.40 or more and 2.00 or less.

[0019] The optical element 100 also includes a first layer 11 made of a cured product of a first polymerizable composition, and a second layer 21 made of a cured product of a second polymerizable composition that is thicker than the first layer 11 and is provided in contact with the first layer 11. When the first layer 11 side is defined as a peak and the second layer 21 side is defined as a valley at the interface S (surface 11b, surface 21a) between the first layer 11 and the second layer 21, the center line average roughness Ra value determined in accordance with JIS B 0601-2001 is 0.010 to 0.100 μm, and the refractive index is 1.40 or more and 2.00 or less.

[0020] This effectively improves the adhesion between the first layer 11 and the second layer 21 while maintaining the optical properties of the optical element 100. That is, by controlling the roughness of the interface S between the first layer 11 and the second layer 21 to a specific numerical range, the fine irregularities at the interface allow the two layers to be tightly intertwined, improving the adhesion while maintaining optical uniformity.

[0021] In the present embodiment, the optical member 100 has the second layer 21 laminated so as to be in contact with the surface 11b of the first layer 11. That is, the interface S between the first layer 11 and the second layer 21 coincides with the surface 11b of the first layer 11 and the surface 21a of the second layer 21.

[0022] In this embodiment, the arithmetic mean height Sa determined in accordance with ISO 4287-1997 is 0.01 to 0.15 μm, preferably 0.015 μm or more, more preferably 0.020 μm or more, and preferably 0.125 μm or less, more preferably 0.100 μm or less. By setting the arithmetic mean height Sa to be equal to or greater than the above-mentioned lower limit, the contact area between the first layer 11 and the second layer 21 can be increased, thereby improving adhesion. On the other hand, by setting the arithmetic mean height Sa to be equal to or less than the above-mentioned upper limit, the first layer 11 and the second layer 21 can be well entangled, thereby improving adhesion.

[0023] In this embodiment, the maximum valley depth Sv determined in accordance with ISO 4287-1997 is 0.20 to 2.00 μm, preferably 0.300 μm or more, more preferably 0.400 μm or more, and preferably 1.75 μm or less, more preferably 1.50 μm or less. By setting the maximum valley depth Sv to the above-mentioned lower limit or more, the contact area between the first layer 11 and the second layer 21 can be increased, thereby improving adhesion. On the other hand, by setting the maximum valley depth Sv to the above-mentioned upper limit or less, the first layer 11 and the second layer 21 can be well entangled, thereby improving adhesion.

[0024] In this embodiment, the centerline average roughness Ra determined in accordance with JIS B 0601-2001 is 0.010 to 0.100 μm, preferably 0.013 μm or more, more preferably 0.015 μm or more, and preferably 0.080 μm or less, more preferably 0.060 μm or less. By setting the centerline average roughness Ra to the above-mentioned lower limit or more, the contact area between the first layer 11 and the second layer 21 can be increased, thereby improving adhesion. On the other hand, by setting the centerline average roughness Ra to the above-mentioned upper limit or less, the first layer 11 and the second layer 21 can be well entangled, thereby improving adhesion.

[0025] The arithmetic mean height Sa, maximum valley depth Sv, and centerline average roughness Ra of the optical member 100 can be measured, for example, as follows: Images are obtained by confocal laser microscope or SEM observation of the surface of the second layer 21 of the optical member 100 after the second layer 21 is formed, or of a cross section opposite to the surface where the second layer 21 and the first layer 11 contact, which includes the optical center of the optical member 100 where the second layer 21 and the first layer 11 contact, and the images are processed to calculate the arithmetic mean height Sa, maximum valley depth Sv, and centerline average roughness Ra.

[0026] The above-mentioned arithmetic mean height Sa, maximum valley depth Sv, and center line average roughness Ra of the optical element 100 can be achieved, for example, by controlling the manufacturing conditions of the second layer 21, the composition of the second polymerizable composition, and the polishing conditions in the polishing step described below.

[0027] The refractive index of the optical member 100 is 1.40 or more and 2.00 or less, preferably 1.425 or more, more preferably 1.45 or more, and preferably 1.90 or less, more preferably 1.80 or less.

[0028] The refractive index is measured in accordance with JIS K7142 (2014).

[0029] The haze value of the optical element 100 of this embodiment, as measured by JIS K7136, is preferably 40% or less, more preferably 35% or less, even more preferably 30% or less, and even more preferably 25% or less. By setting the haze value to the upper limit or less, the transparency of the interface between the first layer 11 and the second layer 21 can be improved, thereby improving the optical properties. The haze value of the optical element 100 of this embodiment, as measured by JIS K7136, is preferably 1% or more, more preferably 5% or more, and even more preferably 10% or more, from the viewpoint of maintaining good transparency while obtaining interlayer adhesion. The haze value of the optical element 100 can be controlled by changing the particle size of the abrasive used during the polishing operation or adjusting the polishing conditions in the manufacturing method of the optical element 100 described below.

[0030] The optical member 100 of this embodiment has a light transmittance at a wavelength of 555 nm of preferably 3 to 97%, more preferably 4 to 96%, and even more preferably 5 to 95%. By setting the light transmittance above the lower limit, it is possible to improve the transparency of the optical member 100. On the other hand, by setting the light transmittance to the upper limit or less, it is possible to easily exhibit the functions of the optical member 100 while maintaining good transparency.

[0031] The light transmittance of the optical element 100 of this embodiment may vary depending on the function of the optical element 100. For example, if the first layer 11 of the optical element 100 contains a photochromic dye and thereby has a photochromic function, the light transmittance is low when the photochromic dye is colored and high when the photochromic dye is decolored. In this case, the difference in light transmittance at a wavelength of 555 nm between when the photochromic dye is colored and when the photochromic dye is decolored is preferably 40% or more, more preferably 50% or more, and even more preferably 60% or more.

[0032] The luminous transmittance of the optical member 100 of this embodiment when colored is preferably 3 to 40%, more preferably 5 to 30%, and even more preferably 10 to 20%. On the other hand, the luminous transmittance of the optical member 100 of this embodiment when decolored is preferably 60 to 97%, more preferably 70 to 96%, and even more preferably 80 to 95%.

[0033] The light transmittance of the optical element 100 can be controlled by adjusting the materials of the first layer 11 and the second layer 21. The light transmittance is measured in accordance with ISO 8930-3.

[0034] In addition, in this embodiment, an example is given in which the second layer 21 is laminated on the surface (surface 11b) of the first layer 11, but the second layer 21 may also be provided on the surface (surface 11a) side of the first layer 11.

[0035] The thickness of the optical member 100 is preferably 0.5 to 25 mm, and more preferably 3 to 12 mm, in order to facilitate improved adhesion.

[0036] Furthermore, when the optical element 100 has a curved surface on at least one side, the radius of curvature is preferably 30 mm or more and 400 mm or less, more preferably 45 mm or more and 350 mm or less, and even more preferably 50 mm or more and 300 mm or less. Furthermore, it is preferable that the radius of curvature of one surface of the optical element 100 is the same as the radius of curvature of the opposite surface. Note that when the optical element 100 has a curved surface, the thickness of the optical element 100 is the geometric center thickness.

[0037] In a plan view of the optical member 100 , the second layer 21 may be included in a region surrounded by the outer edge of the first layer 11 .

[0038] Each component of the optical member 100 will be described below.

[0039] [First Layer 11 ] The first layer 11 is provided so as to be in contact with the surface 21 a of the second layer 21 .

[0040] The average thickness of the first layer 11 is preferably 0.1 to 5 mm, more preferably 0.2 to 3 mm, and even more preferably 0.4 to 2 mm. The first layer 11 may have any thickness as long as it is thinner than the second layer 21.

[0041] The refractive index of the first layer 11 is preferably 1.50 to 1.67, more preferably 1.52 to 1.65, and even more preferably 1.55 to 1.63. By setting the refractive index of the first layer 11 within the above range, the function as a spectacle lens can be exhibited.

[0042] Furthermore, the absolute value of the difference between the refractive index of the first layer 11 and the refractive index of the second layer 21 described below is preferably 0.45 or less, more preferably 0.30 or less, even more preferably 0.20 or less, and particularly preferably 0.15 or less. By setting the absolute value of the difference in refractive index to the above upper limit or less, optical reflection at the interface between the resins (the interface between the first layer 11 and the second layer 21) can be suppressed.

[0043] The first layer 11 has at least one curved surface, and the radius of curvature is preferably 30 mm to 400 mm, more preferably 45 mm to 350 mm, and even more preferably 50 mm to 300 mm. Furthermore, it is preferable that the radius of curvature of one surface of the first layer 11 is the same as the radius of curvature of the opposite surface.

[0044] By imparting a desired function such as a photochromic function to the first layer 11, an optical member 100 having the desired function can be obtained.

[0045] (First Polymerizable Composition) The first layer 11 is made of a cured product of the first polymerizable composition. The first layer 11 preferably contains, as a resin component of the first polymerizable composition, one or more resins selected from the group consisting of (thio)urethane-based resins, episulfide-based resins, polycarbonate-based resins, (meth)acrylic-based resins, and epoxy-based resins.

[0046] Furthermore, the first polymerizable composition preferably has a different composition from the second polymerizable composition. A different composition refers to, for example, different types of resin components or different blending ratios. Here, different compositions are expected to reduce the surface adhesion between the first layer 11 and the second layer 21. However, in the optical member 100 of this embodiment, the interface between the first layer 11 and the second layer 21 is controlled to have a predetermined roughness (arithmetic mean height Sa, maximum valley depth Sv, centerline average roughness Ra), thereby achieving good interlayer adhesion. In particular, the first layer 11 preferably contains a (thio)urethane-based resin. In this case, the first polymerizable composition preferably contains a polyol compound. This allows for good interlayer adhesion while achieving good optical properties. Furthermore, when the first layer 11 contains a (thio)urethane-based resin, the second layer 21 preferably contains an episulfide-based resin. The present inventors have found that when the first layer 11 contains a (thio)urethane-based resin and the second layer 21 contains an episulfide-based resin, the interlayer adhesion between the two layers is significantly reduced. Therefore, in the optical member 100 of this embodiment, the interface between the first layer 11 and the second layer 21 is controlled to have predetermined roughnesses (arithmetic mean height Sa, maximum valley depth Sv, and center line average roughness Ra), so that good interlayer adhesion can be obtained even when the first layer 11 contains a (thio)urethane-based resin and the second layer 21 contains an episulfide-based resin.

[0047] Each resin will be described below.

[0048] [(Thio)urethane Resin] Urethane resins are obtained by reacting polyisocyanate (a compound having an -NCO group) with polyol (a compound having a polyvalent hydroxyl group). Thiourethane resins are resins containing a thiourethane structure, and are obtained by reacting an iso(thio)cyanate group, which is a polymerizable functional group of a polyiso(thio)cyanate compound, with a thiol group, which is a polymerizable functional group of a polythiol compound. In particular, (thio)urethane resins preferably comprise a structural unit derived from an iso(thia)cyanate compound (a) and at least one of a structural unit derived from a thiol compound (b) and a structural unit derived from a polyol compound (c).

[0049] (Iso(thio)cyanate compound (a)) The iso(thio)cyanate compound (a) is an iso(thio)cyanate compound having two or more iso(thio)cyanato groups, and here, the iso(thio)cyanate compound means an isocyanate compound or an isothiocyanate compound.

[0050] Examples of the iso(thio)cyanate compound (a) of the present embodiment include alicyclic polyiso(thio)cyanate compounds, aromatic polyiso(thio)cyanate compounds, and modified products thereof.

[0051] More specifically, the isocyanate compound includes isophorone diisocyanate, hexamethylene diisocyanate, bis(isocyanatomethyl)cyclohexane, dicyclohexylmethane-4,4'-diisocyanate, cyclohexane diisocyanate, methylcyclohexane diisocyanate, dicyclohexyldimethylmethane isocyanate, 2,5-bis(isocyanatomethyl)bicyclo-[2.2.1]-heptane, 2,6-bis(isocyanatomethyl)bicyclo-[2.2.1]-heptane, 3,8-bis(isocyanatomethyl)bicyclo-[2.2.1]-heptane, alicyclic polyisocyanate compounds such as bis(isocyanatomethyl)tricyclodecane, 3,9-bis(isocyanatomethyl)tricyclodecane, 4,8-bis(isocyanatomethyl)tricyclodecane, and 4,9-bis(isocyanatomethyl)tricyclodecane; and aromatic polyisocyanate compounds such as phenylene diisocyanate, 2,4-tolylene diisocyanate, 2,6-tolylene diisocyanate, 4,4'-diphenylmethane diisocyanate, and diphenyl sulfide-4,4'-diisocyanate.

[0052] Examples of the iso(thio)cyanate compound include isophorone diisothiocyanate, bis(isothiocyanatomethyl)cyclohexane, dicyclohexylmethane diisothiocyanate, cyclohexane diisothiocyanate, methylcyclohexane diisothiocyanate, 2,5-bis(isothiocyanatomethyl)bicyclo-[2.2.1]-heptane, 2,6-bis(isothiocyanatomethyl)bicyclo-[2.2.1]-heptane, 3,8-bis(isothiocyanatomethyl)bicyclo-[2.2.1]-heptane, alicyclic polyisothiocyanate compounds such as 3,9-bis(isothiocyanatomethyl)tricyclodecane, 3,9-bis(isothiocyanatomethyl)tricyclodecane, 4,8-bis(isothiocyanatomethyl)tricyclodecane, and 4,9-bis(isothiocyanatomethyl)tricyclodecane; and aromatic polyisothiocyanate compounds such as tolylene diisothiocyanate, 4,4'-diphenylmethane diisothiocyanate, and diphenyl disulfide-4,4'-diisothiocyanate.

[0053] The iso(thio)cyanate compound (a) may also be a halogen-substituted compound such as a chlorine-substituted compound or a bromine-substituted compound, an alkyl-substituted compound, an alkoxy-substituted compound, a nitro-substituted compound, a prepolymer-type modified compound with a polyhydric alcohol, a carbodiimide-modified compound, a urea-modified compound, a biuret-modified compound, a dimerization or trimerization reaction product, etc. The iso(thio)cyanate compound (a) may be used alone or in combination of two or more selected from these.

[0054] Among these, it is preferable that the difunctional or higher iso(thio)cyanate compound (a) is one or more selected from xylylene diisocyanate or a hydrogenated product thereof, 2,5-bis(isocyanatomethyl)bicyclo-[2.2.1]-heptane, 2,6-bis(isocyanatomethyl)bicyclo-[2.2.1]-heptane, tolylene diisocyanate, 4,4'-diphenylmethane diisocyanate, isophorone diisocyanate, hexamethylene diisocyanate, 1,3-bis(isocyanatomethyl)cyclohexane, bis(isocyanatocyclohexyl)methane, and phenylene diisocyanate.

[0055] The content of the difunctional or higher iso(thio)cyanate compound (a) is preferably 40 to 60% by mass, more preferably 45 to 55% by mass, and even more preferably 48 to 52% by mass, based on the total amount of the first layer 11.

[0056] The (thio)urethane resin is not particularly limited, and examples thereof include thiourethane resins described in known documents such as JP-A-63-46213, JP-A-2-270859, JP-A-7-252207, and WO 2008 / 047626.

[0057] (Thiol Compound (b)) Examples of the thiol compound (b) include polythiol compounds having two or more mercapto groups, and these compounds are used alone or in combination. Examples of these polythiol compounds include the compounds exemplified in WO 2016 / 125736.

[0058] Examples of the thiol compound (b) include 4-mercaptomethyl-1,8-dimercapto-3,6-dithiaoctane, 5,7-dimercaptomethyl-1,11-dimercapto-3,6,9-trithiaundecane, 4,7-dimercaptomethyl-1,11-dimercapto-3,6,9-trithiaundecane, 4,8-dimercaptomethyl-1,11-dimercapto-3,6,9-trithiaundecane, pentaerythritol tetrakis(2-mercapto acetate), pentaerythritol tetrakis(3-mercaptopropionate), bis(mercaptoethyl)sulfide, 2,5-dimercaptomethyl-1,4-dithiane, 1,1,3,3-tetrakis(mercaptomethylthio)propane, 4,6-bis(mercaptomethylthio)-1,3-dithiane, and 2-(2,2-bis(mercaptomethylthio)ethyl)-1,3-dithietane.

[0059] The content of the thiol compound (b) is preferably 40 to 60% by mass, more preferably 45 to 55% by mass, and even more preferably 48 to 52% by mass, based on the total mass of the first layer 11.

[0060] (Polyol Compound (c)) One or more compounds selected from linear or branched chain aliphatic polyols (i), alicyclic polyols (ii), and polyether polyols (iii) can be used.

[0061] Examples of the linear or branched aliphatic polyol (i) include ethylene glycol, diethylene glycol, triethylene glycol, propylene glycol, dipropylene glycol, tripropylene glycol, 1,3-propanediol, 2,2-dimethyl-1,3-propanediol, 2,2-diethyl-1,3-propanediol, 1,2-butanediol, 1,3-butanediol, 1,4-butanediol, 3-methyl-1,3-butanediol, 1,2-pentanediol, 1,3-pentanediol, 1,5-pentanediol, 2,4-pentanediol, 2-methyl-2,4-pentanediol, 3-methyl-1,5-pentanediol, 1,6-hexanediol, 2,5-hexanediol, glycerol, diglycerol, polyglycerol, trimethylolpropane, pentaerythritol, and di(trimethylolpropane).

[0062] Examples of the alicyclic polyol (ii) include 1,2-cyclopentanediol, 1,3-cyclopentanediol, 3-methyl-1,2-cyclopentanediol, 1,2-cyclohexanediol, 1,3-cyclohexanediol, 1,4-cyclohexanediol, 4,4'-bicyclohexanol, and 1,4-cyclohexanedimethanol.

[0063] The polyether polyol (iii) is a block copolymer containing at least one polyether segment, which may be combined with at least one segment of polyester, polycarbonate, poly(meth)acrylate, polyamide, polyethyleneimine, polysiloxane, polysulfide, polyolefin, or polystyrene. Among these, a hydroxyl group-containing polyether compound having hydroxyl groups is preferred.

[0064] The hydroxyl group-containing polyether compound is preferably a block copolymer which may be combined with at least one segment of polyester, polycarbonate, poly(meth)acrylate, polyamide, polyethyleneimine, polysiloxane, polysulfide, polyolefin, or polystyrene, in addition to polyether.

[0065] Another embodiment of the hydroxyl group-containing polyether compound of this embodiment is a linear polyether block copolymer having at least two different segments, such as a segment structure having a divalent organic group derived from ethylene glycolate, propylene glycolate, butylene glycolate, or the like, or a segment structure having a divalent organic group derived from ethanedithiol, propanedithiol, or the like.

[0066] The polyether is not particularly limited, but examples thereof include polyethylene glycol, polypropylene glycol, and polybutylene glycol.

[0067] The polyesters include, but are not limited to, those obtained by condensation of dicarboxylic acids and diols.

[0068] The dicarboxylic acid may include adipic acid, succinic acid, or a combination thereof.

[0069] Examples of the diol include ethylene-1,2-diol, butane-1,4-diol, hexane-1,6-diol, propane-1,2-diol, 3-methylpentane-1,5-diol, 2-methylpropane-1,3-diol, 2,2-dimethylpropane-1,3-diol, diethylene glycol, triethylene glycol, dipropylene glycol, tripropylene glycol, pentane-1,5-diol, heptane-1,7-diol, and the like, or combinations thereof.

[0070] The polyester may also include polycaprolactone, polybutyrolactone, polyvalerolactone, polylactic acid, polyglycolic acid, or combinations thereof.

[0071] The polycarbonate is not particularly limited, but examples thereof include those obtained by condensation of carbonate and diol.

[0072] Examples of the diol include ethylene-1,2-diol, butane-1,4-diol, hexane-1,6-diol, propane-1,2-diol, 3-methylpentane-1,5-diol, 2-methylpropane-1,3-diol, 2,2-dimethylpropane-1,3-diol, pentane-1,5-diol, heptane-1,7-diol, diethylene glycol, triethylene glycol, dipropylene glycol, tripropylene glycol, and the like, or combinations thereof.

[0073] The poly(meth)acrylate is not particularly limited, but examples thereof include methyl (meth)acrylate, butyl (meth)acrylate, hexyl (meth)acrylate, 2-ethylhexyl (meth)acrylate, 2-hydroxyethyl (meth)acrylate, benzyl (meth)acrylate, phenyl (meth)acrylate, and the like, or combinations thereof.

[0074] The polyamide is not particularly limited, but examples thereof include those obtained by condensation of dicarboxylic acid and diamine.

[0075] The dicarboxylic acid may be adipic acid, succinic acid, or a combination thereof. The diamine may be hexamethylenediamine.

[0076] The polyamide may also include lactams such as polycaprolactam.

[0077] The polyethyleneimine may be a polyethyleneimine chain, which is a polymer chain, such as a polyethyleneimine chain, a polypropionylaziridine chain, a polyacetylaziridine chain, or a polyformylaziridine chain.

[0078] The polysiloxane may be a polysiloxane chain, which is a polymer chain, such as a polydimethylsiloxane chain or a polymethylphenylsiloxane chain.

[0079] The polysulfide may contain a polyethylene sulfide chain or the like.

[0080] The polyolefin may include polyethylene, polypropylene, and the like, or a combination thereof.

[0081] The polystyrene may include polystyrene, polystyrene sulfonate, and the like, or a combination thereof.

[0082] The hydroxyl group-containing polyether compound of this embodiment forms a domain structure. Specifically, it is possible to form micelles by microphase separation, thereby providing uniformly dispersed nano-sized structures. The micellar structure can effectively disperse functional compounds such as photochromic dyes in the optical element 100 of this embodiment while maintaining the mechanical and optical properties.

[0083] The number of hydroxyl groups per molecule of the hydroxyl group-containing polyether compound is preferably 1 to 10, more preferably 1 to 8, and even more preferably 1 to 6. By setting the number of hydroxyl groups per molecule of the hydroxyl group-containing polyether compound within the above numerical range, the compound can more easily exhibit its functions, and performance such as the color development density and color development / fading speed of the photochromic compound can be improved.

[0084] The number-average molecular weight of the hydroxyl group-containing polyether compound is preferably 500 to 50,000, more preferably 1,000 to 30,000, and even more preferably 2,000 to 20,000. By setting the number-average molecular weight of the hydroxyl group-containing polyether compound to the above-mentioned lower limit or more, photochromic performance is easily improved. On the other hand, by setting the number-average molecular weight of the hydroxyl group-containing polyether compound to the above-mentioned upper limit or less, clouding of the optical element 100 can be suppressed while maintaining good photochromic function.

[0085] The content of the hydroxyl group-containing polyether compound is preferably 1 to 25% by mass, more preferably 2 to 20% by mass, and even more preferably 3 to 18% by mass, based on the total mass of the first layer 11 .

[0086] [Episulfide Resin] The episulfide resin is a resin containing a sulfide structure, and is preferably composed of structural units derived from an episulfide compound, or composed of structural units derived from an episulfide compound and structural units derived from a polythiol compound.

[0087] The episulfide compound refers to a compound having two or more episulfide groups per molecule. Examples of episulfide compounds include epithioethylthio compounds, chain aliphatic 2,3-epithiopropylthio compounds, cyclic aliphatic 2,3-epithiopropylthio compounds, aromatic 2,3-epithiopropylthio compounds, chain aliphatic 2,3-epithiopropyloxy compounds, cyclic aliphatic 2,3-epithiopropyloxy compounds, and aromatic 2,3-epithiopropyloxy compounds. More specifically, examples include bis(2,3-epithiopropyl)sulfide, bis(2,3-epithiopropyl)disulfide, and 2,5-bis(2,3-epithiopropylthiomethyl)-1,4-dithiane. Further examples of episulfide compounds include the compounds exemplified in WO 2015 / 137401 and WO 2025 / 013882. These episulfide compounds can be used alone or in combination of two or more.

[0088] [Polycarbonate Resin] Polycarbonate resins may be produced by a phosgene method in which a dihydroxydiaryl compound is reacted with phosgene, or an ester exchange method in which a dihydroxydiaryl compound is reacted with a carbonate ester such as diphenyl carbonate.

[0089] The polycarbonate resin may be a polycarbonate resin produced from 2,2-bis(4-hydroxyphenyl)propane (also known as bisphenol A), a polycarbonate resin produced from 1,1-bis(4-hydroxyphenyl)cyclohexane, a polycarbonate resin produced from 1,1-bis(4-hydroxyphenyl)-3,3,5-trimethylcyclohexane, a polycarbonate resin produced from 9,9-bis(4-hydroxyphenyl)fluorene, a polycarbonate resin produced from 9,9-bis[4-(2-hydroxyethyloxy)phenyl]fluorene, a copolymer polycarbonate resin produced from a mixture of dihydroxydiaryl compounds, or a mixture of the above-mentioned polycarbonate resins.

[0090] The viscosity average molecular weight of the polycarbonate resin is usually 10,000 to 100,000, preferably 10,000 to 400,000.

[0091] [(Meth)acrylic Resin] In order to obtain good optical properties, the (meth)acrylic resin is preferably a (meth)acrylic resin containing methyl methacrylate as a structural unit. The content of methyl methacrylate in the (meth)acrylic resin is preferably 30 to 100% by mass, more preferably 50 to 100% by mass, even more preferably 50 to 99.9% by mass, and particularly preferably 50 to 98% by mass. The content of other vinyl monomers copolymerizable with methyl methacrylate in the (meth)acrylic resin is preferably 0 to 70% by mass, more preferably 0 to 50% by mass, even more preferably 0.1 to 50% by mass, and particularly preferably 2 to 50% by mass.

[0092] As other vinyl monomers copolymerizable with methyl methacrylate, for example, (meth)acrylic acid esters (excluding methyl methacrylate) having an alkyl group with 1 to 10 carbon atoms are preferred. Examples of other vinyl monomers copolymerizable with methyl methacrylate include methacrylic acid esters such as ethyl methacrylate, propyl methacrylate, butyl methacrylate, cyclohexyl methacrylate, 2-ethylhexyl methacrylate, benzyl methacrylate, octyl methacrylate, glycidyl methacrylate, epoxycyclohexylmethyl methacrylate, dimethylaminoethyl methacrylate, 2-hydroxyethyl methacrylate, 2-hydroxypropyl methacrylate, dicyclopentanyl methacrylate, 2,2,2-trifluoroethyl methacrylate, 2,2,2-trichloroethyl methacrylate, isobornyl methacrylate, methacrylamide, and N-methylolmethacrylamide; and methyl acrylate, ethyl acrylate, propyl acrylate, butyl acrylate, 2-ethylhexyl acrylate, octyl acrylate, glycidyl acrylate, epoxycyclohexylmethyl acrylate, 2-hydroxyethyl acrylate, 2-hydroxypropyl acrylate. Examples of suitable vinyl monomers include acrylic acid esters such as propyl acrylate, acrylamide, and N-methylol acrylamide; carboxylic acids and salts thereof such as methacrylic acid and acrylic acid; vinyl cyanides such as acrylonitrile and methacrylonitrile; vinyl arenes such as styrene, α-methylstyrene, monochlorostyrene, and dichlorostyrene; maleimides such as N-phenylmaleimide, N-cyclohexylmaleimide, and N-methylmaleimide; maleic acid, fumaric acid, and esters thereof; vinyl halides such as vinyl chloride, vinyl bromide, and chloroprene; vinyl esters such as vinyl formate, vinyl acetate, and vinyl propionate; alkenes such as ethylene, propylene, butylene, butadiene, and isobutylene; halogenated alkenes; and polyfunctional monomers such as allyl methacrylate, diallyl phthalate, triallyl cyanurate, monoethylene glycol dimethacrylate, tetraethylene glycol dimethacrylate, tetraethylene glycol dimethacrylate, and divinylbenzene. These vinyl monomers may be used alone or in combination of two or more.

[0093] [Epoxy Resin] Examples of epoxy resins include aliphatic glycidyl ether type epoxy compounds, hydrogenated epoxy compounds, alicyclic epoxy compounds, aromatic epoxy compounds, glycidyl ester compounds, glycidyl amine compounds, and heterocyclic epoxy compounds, and these can be used alone or in combination of two or more.

[0094] In particular, the first polymerizable composition preferably contains a polyol compound.

[0095] The first polymerizable composition may further contain a dye. By containing a dye, the optical member 100 can be colored, thereby improving functionality, design, and the like. Furthermore, the optical member 100 can be used as a photochromic lens. The dye is not particularly limited, but examples thereof include visible light absorbing dyes and photochromic dyes. Among these, it is preferable to contain a photochromic dye.

[0096] (Photochromic Dye) Photochromic dyes include compounds whose absorption characteristics (absorption spectrum) change with respect to light of a specific wavelength.

[0097] As the photochromic dye of this embodiment, known compounds can be used, and can be obtained by the methods described in, for example, WO 2009 / 146509, WO 2010 / 20770, WO 2012 / 149599, and WO 2012 / 162725. Specific examples include spiropyran compounds, spirooxazine compounds, fulgide compounds, naphthopyran compounds, and bisimidazole compounds. Among these, naphthopyran compounds and spiropyran compounds are preferred, and naphthopyran compounds having no active hydrogen are more preferred.

[0098] The content of the photochromic dye is preferably 0.1 to 5% by mass, more preferably 0.2 to 2% by mass, and even more preferably 0.3 to 1% by mass, based on the total mass of the first layer 11.

[0099] (Others) The first polymerizable composition may further contain known additives such as an ultraviolet absorber, a blooming agent, a resin modifier, a light stabilizer, an antioxidant, and a coloring inhibitor, depending on the properties desired for the application to which it is applied.

[0100] The viscosity of the first polymerizable composition used in this embodiment is preferably 5 to 1000 mPa·s, and more preferably 10 to 500 mPa·s, in order to facilitate application to the production method described below.

[0101] [Second Layer 21] The second layer 21 serves as the base of the optical member 100 and defines the outer shape of the optical member 100. The second layer 21 is configured to be thicker than the first layer 11.

[0102] The ratio of the thickness (mm) of the second layer 21 to the thickness (mm) of the first layer 11 (thickness of the second layer 21 / thickness of the first layer 11) is greater than 1, preferably 1.5 to 200, more preferably 2 to 100, and even more preferably 5 to 20.

[0103] The thickness of the second layer 21 is preferably 0.5 to 20 mm, more preferably 1.0 to 17 mm, and even more preferably 2.0 to 15 mm. When the second layer 21 has a curved surface, the thickness is the geometric center thickness.

[0104] The second layer 21 may have a flat or curved surface depending on the purpose of the optical lens. Furthermore, the second layer 21 has at least one curved surface, and the radius of curvature is preferably greater than 0 and less than 400 mm, more preferably 5 mm or more and less than 380 mm, more preferably 30 mm or more and less than 360 mm, even more preferably 45 mm or more and less than 350 mm, and even more preferably 50 mm or more and less than 300 mm. Furthermore, the radius of curvature of one surface of the second layer 21 and the radius of curvature of the opposite surface are preferably the same.

[0105] The refractive index of the second layer 21 is preferably 1.40 to 2.00, more preferably 1.42 to 1.90, and even more preferably 1.45 to 1.80. By setting the refractive index of the second layer 21 within the above range, the function as a spectacle lens can be exhibited.

[0106] (Second Polymerizable Composition) The second layer 21 is made of a cured product of the second polymerizable composition. The second layer 21 preferably contains, as the resin component of the second polymerizable composition, one or more resins selected from the group consisting of (thio)urethane-based resins, episulfide-based resins, polycarbonate-based resins, (meth)acrylic-based resins, and epoxy-based resins. This allows for good optical properties to be obtained. Examples of these resins include those similar to those described for the first layer 11.

[0107] The second layer 21 and the first layer 11 may contain the same resin or different resins.

[0108] The second layer 21 preferably contains an episulfide-based resin. This improves adhesion while providing good optical properties. In this case, the second polymerizable composition preferably contains an episulfide compound. Furthermore, as described above, when the first layer 11 contains a (thio)urethane-based resin, the second layer 21 preferably contains an episulfide-based resin. This makes it possible to obtain good interlayer adhesion even when the first layer 11 contains a (thio)urethane-based resin and the second layer 21 contains an episulfide-based resin.

[0109] (Others) The second polymerizable composition may further contain additives such as a catalyst, an internal mold release agent, a resin modifier, a light stabilizer, an antioxidant, and a color inhibitor, depending on the properties desired for the application to which it is applied.

[0110] The catalyst may be, for example, one or more selected from Lewis acids, tertiary amines, organic acids, and amine-organic acid salts, etc. Among these, Lewis acids, amines, and amine-organic acid salts are preferred, and dimethyltin chloride, dibutyltin dichloride, and dibutyltin laurate are more preferred.

[0111] An internal mold release agent may be contained for the purpose of improving releasability from the mold after molding. An acidic phosphate ester can be used as the internal mold release agent. Examples of acidic phosphate esters include monophosphate esters and diphosphate esters, each of which can be used alone or in combination of two or more. Examples of commercially available internal mold release agents include ZelecUN manufactured by STEPAN Corporation, MR internal mold release agents manufactured by Mitsui Chemicals, Inc., the JP series manufactured by Johoku Chemical Industry Co., Ltd., the Phosphanol series manufactured by Toho Chemical Industry Co., Ltd., and the AP and DP series manufactured by Daihachi Chemical Industry Co., Ltd.

[0112] A resin modifier may be contained for the purpose of adjusting various physical properties such as optical properties, impact resistance, specific gravity, etc., and adjusting viscosity and pot life. Examples of the resin modifier include episulfide compounds, alcohol compounds other than the above-mentioned polyol compounds, amine compounds other than the above-mentioned amine compounds, epoxy compounds, organic acids and anhydrides thereof, and olefin compounds including (meth)acrylate compounds.

[0113] The light stabilizer may be a hindered amine compound having a 2,2,6,6-tetramethylpiperidine skeleton or a 1,2,2,6,6-pentamethylpiperidine skeleton. Commercially available hindered amine compounds include Lowilite 76 and Lowilite 92 manufactured by Chemtura Corporation, Tinuvin 144, Tinuvin 292, and Tinuvin 765 manufactured by BASF, Adekastab LA-52 and LA-72 manufactured by ADEKA Corporation, JF-95 manufactured by Johoku Chemical Industry Co., Ltd., and Hostavin PR-25 manufactured by Clariant Chemicals.

[0114] <Method for Manufacturing Optical Member 100> Next, an example of a method for manufacturing the optical member 100 of this embodiment will be described.

[0115] The method for producing an optical member 100 of this embodiment includes a first layer 11 made of a cured product of a first polymerizable composition, and a second layer 21 made of a cured product of a second polymerizable composition that is thicker than the first layer 11 and is provided in contact with the first layer 11, and has a refractive index of 1.40 or more and 2.00 or less, and includes at least the following steps: curing the second polymerizable composition to form the second layer 21; polishing one surface 21a of the second layer 21 so that the arithmetic mean height Sa, as determined in accordance with ISO 4287-1997, is 0.01 to 0.15 μm and the maximum valley depth Sv is 0.2 to 2 μm (step 2); and forming the first layer 11 made of the cured product of the first polymerizable composition on the polished surface 21a of the second layer 21. This allows for improved interlayer adhesion while maintaining optical properties.

[0116] Each step will be described in detail below.

[0117] (Step 1) First, the second polymerizable composition is cured to form the second layer 21. Specifically, the second polymerizable composition is prepared, and the second layer 21 can be obtained by curing the composition by thermal polymerization under curing conditions of, for example, 20°C to 150°C for 48 hours or less.

[0118] (Step 2) Next, one surface 21a of the second layer 21 is polished so that the arithmetic mean height Sa of the surface 21a determined in accordance with ISO 4287-1997 is 0.01 to 0.15 μm and the maximum valley depth Sv is 0.2 to 2 μm.

[0119] The arithmetic mean height Sa is 0.010 to 0.150 μm, preferably 0.015 μm or more, more preferably 0.020 μm or more, and preferably 0.125 μm or less, more preferably 0.100 μm or less. The maximum valley depth Sv is 0.20 to 2.00 μm, preferably 0.300 μm or more, more preferably 0.400 μm or more, and preferably 1.75 μm or less, more preferably 1.50 μm or less.

[0120] The second layer 21 can be polished using an abrasive. The average particle size of the abrasive is preferably 5 to 15 μm, and more preferably 7 to 13 μm in terms of improving adhesion.

[0121] It is also preferable to use an abrasive consisting of one or more materials selected from the group consisting of alumina, diamond powder, boron nitride, cerium oxide, and zirconium oxide, and among these, it is preferable to use one material selected from diamond powder and alumina.

[0122] Furthermore, a step of cleaning the second layer 21 (step 2') may be included after the main polishing step (step 2) and before the step of forming the first layer 11 (step 3) described below.

[0123] By cleaning, polishing residues are removed, and good optical properties can be obtained while further improving the adhesion between the first layer 11 and the second layer 21. The cleaning method is not particularly limited, and known methods such as ultrasonic treatment can be used.

[0124] (Step 3) Next, a first layer 11 made of a cured product of the first polymerizable composition is formed on the polished surface 21a of the second layer 21. The lamination method is not particularly limited, and known methods can be used. Examples include (i) a method of laminating a film made of the first polymerizable composition onto at least the polished surface 21a of the second layer 21, and (ii) a method of placing the second layer 21 along the inner wall of a mold cavity held in place by a gasket, tape, or the like, and then injecting and curing the first polymerizable composition into the cavity.

[0125] The film made of the first polymerizable composition used in the above method (i) is not particularly limited, and any known method can be used to bond a film made of the first polymerizable composition obtained by melt-kneading, impregnation, or the like onto the surface of the second layer 21. The film can be obtained by any of various conventionally known methods, specifically, for example, injection molding, profile extrusion molding, pipe molding, tube molding, coating molding of heterogeneous molded bodies, injection blow molding, direct blow molding, T-die sheet or film molding, inflation film molding, press molding, or the like.

[0126] The cast polymerization in the above method (ii) can be carried out, for example, using a known casting molding apparatus according to the following procedure. Fig. 2 is a cross-sectional view schematically illustrating an example of a manufacturing process for the optical element 100 of this embodiment. Fig. 2 shows the casting molding apparatus including the second layer 21, a substrate 30 disposed opposite the surface 21a of the second layer 21, a fixing member 31 for fixing the peripheral edge of the second layer 21 and the peripheral edge of the substrate 30, and a casting portion provided on the fixing member 31.

[0127] The first layer 11 can be laminated on the surface 21 a of the second layer 21 by injecting the first polymerizable composition into the gap 20 from the injection portion and polymerizing and curing it.

[0128] The second layer 21 and the substrate 30 may have curved surfaces and may be substantially circular in plan view. The gap 20 is formed by being sandwiched between the second layer 21 and the substrate 30, and therefore the shape, thickness, etc. of the gap 20 are adjusted according to the shapes of the second layer 21 and the substrate 30. The first layer 11 is also designed according to the shape, thickness, etc. of the gap 20.

[0129] The material constituting the substrate 30 is not particularly limited, but can be glass, metal, resin, etc. The substrate 30 can be later peeled off to obtain a laminate of the substrate 30 and the second layer 21 that will be formed later in the gap 20. Alternatively, the substrate 30 can be used as is to form a laminate of the first layer 11, a thin-film molded body, and the substrate 30.

[0130] The polymerization conditions of the first polymerizable composition for forming the first layer 11 are not limited because they vary depending on the composition and amount of the second polymerizable composition, the type and amount of the catalyst used, the shape of the mold, etc., but are generally carried out at a temperature of approximately −50 to 150° C. for 1 to 50 hours.

[0131] In this manner, the optical member 100 of this embodiment can be manufactured. Note that the above manufacturing method is an example, and the manufacturing method of the optical member 100 of this embodiment is not limited to this. For example, in step 2, one surface 21a of the second layer 21 may be polished so that the center line average roughness Ra of surface 21a determined in accordance with JIS B 0601-2001 is 0.10 to 0.100 μm.

[0132] <Applications, Optical Lens> Applications of the optical member 100 of this embodiment include plastic lenses, camera lenses, light-emitting diode lenses, light-emitting diode lens cases, prisms, optical fibers, information recording substrates, filters, etc. In particular, it is suitable as an optical material or optical element for plastic lenses, camera lenses, light-emitting diode lenses, light-emitting diode lens cases, etc. Among these, it is suitable as an optical lens having a photochromic function (photochromic lens).

[0133] An optical lens including the optical member 100 of this embodiment may be used as a laminated plastic lens by applying a coating layer to one or both sides of the lens substrate made of the optical member 100, as needed. Examples of coating layers include a primer layer, a hard coat layer, an anti-reflection film layer, an anti-fogging coating film layer, an anti-fouling layer, and a water-repellent layer. These coating layers may be used alone or in combination with multiple coating layers. When coating layers are applied to both sides, the same coating layer or different coating layers may be applied to each side.

[0134] These coating layers may each contain an infrared absorber to protect the eyes from infrared rays, a light stabilizer, an antioxidant, an antistatic agent to improve the weather resistance of the lens, or other known additives to enhance lens performance. A coating layer such as a hard coat layer or an antireflection coat, or a primer layer may also be provided.

[0135] Although the embodiments of the present invention have been described above, these are merely examples of the present invention, and various other configurations can also be adopted.

[0136] Next, the present invention will be described in detail with reference to examples, but the content of the present invention is not limited to the examples.

[0137] <Examples and Comparative Examples> (1) Preparation of Episulfide-Based Resin Substrate (Second Layer) An episulfide-based resin substrate was prepared by the following procedure. First, 1.0 part by mass of Tinuvin PS was added to 90 parts by mass of bis(β-epithiopropyl) disulfide (episulfide compound), and the mixture was stirred at 20°C for 30 minutes to dissolve. 6.49 parts by mass of 4,8-dimercaptomethyl-1,11-dimercapto-3,6,9-trithiaundecane was added to the resulting solution, and the mixture was stirred at 20°C for 10 minutes to prepare Solution A. Separately, a bluing master solution was prepared by adding 0.001 parts by weight of Plast Red 8320 manufactured by Arimoto Chemical Industry Co., Ltd. and 0.002 parts by weight of Plast Blue 8514 manufactured by Arimoto Chemical Industry Co., Ltd. to 40 parts by weight of a composition containing 5,7-dimercaptomethyl-1,11-dimercapto-3,6,9-trithiaundecane, 4,7-dimercaptomethyl-1,11-dimercapto-3,6,9-trithiaundecane, and the mixture was stirred at 15 to 25° C. for 30 minutes to dissolve the mixture. To solution A, 1.94 parts by weight of Bluing master solution was added, and the mixture was stirred at 20°C for 10 minutes to prepare solution B. Next, to prepare an N,N-dimethylcyclohexylamine catalyst master solution, 0.1 parts by weight of N,N-dimethylcyclohexylamine was added to 5 parts by weight of 4,8-dimercaptomethyl-1,11-dimercapto-3,6,9-trithiaundecane, and the mixture was stirred at 15 to 25°C for 60 minutes to dissolve the mixture. To solution B, 0.1 parts by weight of N-methyldicyclohexylamine and 0.58 parts by weight of N,N-dimethylcyclohexylamine catalyst master solution were added, and the mixture was stirred at 20°C for 10 minutes to prepare a polymerizable composition. Thereafter, the polymerizable composition was stirred and degassed for 10 minutes at a temperature between 10°C and 20°C under a reduced pressure environment of 400 Pa or less, and then filtered using a 1.0 μm PTFE (polytetrafluoroethylene) filter. The obtained polymerizable composition was poured into the space surrounded by glass molds, and then heated from 10°C to 120°C over 32 hours.Thereafter, it was cooled to room temperature and removed from the glass mold to obtain an episulfide-based resin substrate (second layer) having a convex surface.

[0138] (Polishing step) The surface (convex surface) of the obtained episulfide-based resin substrate (second layer) was subjected to a polishing treatment using an abrasive shown in Table 1. The polishing device used was a POLISHING MACHINE manufactured by MENTEE N TOR, Inc., and the rotation speed was set to 17,000 rpm (17,000 revolutions per minute). However, polishing was not performed in Comparative Example 1.

[0139] (Cleaning Step) Thereafter, ultrasonic cleaning was carried out using a cleaning machine for eyeglass lenses (multi-layer type), and it was confirmed that the abrasive used did not remain on the surface of the episulfide-based resin substrate (second layer).

[0140] (2) Preparation of First Polymerizable Composition for Photochromic Functional Layer (First Layer) <Raw Materials> Iso(thio)cyanate compound: An isocyanate composition mainly composed of a mixture of 2,5-bis(isocyanatomethyl)bicyclo-[2.2.1]-heptane and 2,6-bis(isocyanatomethyl)bicyclo-[2.2.1]-heptane Hydroxyl group-containing polyether compound: Polyethylene glycol Polypropylene glycol Polyethylene glycol (Pluronic L64, manufactured by BASF) Thiol compound: A polythiol composition mainly composed of 4-mercaptomethyl-1,8-dimercapto-3,6-dithiaoctane

[0141] A master liquid was prepared in advance by dissolving 0.305 parts by weight of Reversacol Wembley Grey and 0.30 parts by weight of Reversacol Heath Green in 19.395 parts by weight of an isocyanate composition containing 2,5-bis(isocyanatomethyl)bicyclo-[2.2.1]-heptane and 2,6-bis(isocyanatomethyl)bicyclo-[2.2.1]-heptane as main components. To 27.7 parts by weight of an isocyanate composition primarily composed of a mixture of 2,5-bis(isocyanatomethyl)bicyclo-[2.2.1]-heptane and 2,6-bis(isocyanatomethyl)bicyclo-[2.2.1]-heptane, 20 parts by weight of the resulting master solution was added and stirred. To this mixture, 15 parts by weight of polyethylene glycol polypropylene glycol polyethylene glycol (Pluronic L64, manufactured by BASF) and 0.3 parts by weight of acidic phosphate ester (JP-506H, manufactured by Johoku Chemical Industry Co., Ltd.) were added, and the mixture was stirred at 15°C to 20°C for 30 minutes. A solution was prepared by adding 0.1 parts by weight of dimethyltin dichloride to 37.3 parts by weight of a thiol composition primarily composed of 4-mercaptomethyl-1,8-dimercapto-3,6-dithiaoctane, and dissolving the mixture uniformly. The resulting mixture was added to this solution and stirred for 15 minutes at 15°C to 20°C to obtain a first polymerizable composition. Thereafter, the first polymerizable composition was stirred and degassed for 1 hour and 30 minutes at 15°C to 20°C in a reduced pressure environment of 400 Pa or less, and then filtered using a 1.0 μm PTFE filter.

[0142] (3) Production of Optical Element Using an injection molding device as shown in Fig. 2, the episulfide-based resin substrate (second layer) prepared in (1) above was set in a mold, and the first polymerizable composition obtained in (2) above was poured into the space surrounded by the glass mold and the episulfide-based resin substrate, and then the temperature was raised from 10°C to 130°C over 24 hours. Thereafter, the mixture was cooled to room temperature, and the glass mold was removed to obtain an optical element that was a photochromic lens in which a photochromic functional layer (first layer) was laminated on the convex surface of the episulfide-based resin substrate (second layer).

[0143] (4) Refractive index (ne): The refractive index was measured at 23°C and 35% humidity using a Shimadzu Kalnew Precision Refractometer KPR-3000 (automatic refractive index measuring instrument) in accordance with JIS K7142 (2014). The results are shown in Table 1.

[0144] (5) Thickness Measurement The thicknesses of the first and second layers at their geometric centers were measured using an SM-130LW manufactured by TECLOCK Co., Ltd. The results are shown in Table 1.

[0145] (6) Surface Roughness (Sa, Sq Values) The episulfide-based resin substrate (second layer) prepared in (1) above was left to stand for 1 hour at 23°C and 50% RH, and then surface roughness was measured under the following conditions. The results are shown in Table 1. The optical center of the convex surface side of the episulfide-based resin substrate (second layer) was observed with a laser microscope. From the obtained height image (2D) and brightness image, the arithmetic mean height Sa and maximum valley depth Sv of the convex surface of the episulfide-based resin substrate (second layer) were calculated. <Measurement Conditions> Confocal Laser Scanning Microscope (LSM) Apparatus: LEXT OLS5100 (manufactured by EVIDENT) Conditions: Objective lens / ×20, Measurement mode / Accuracy priority Correction: Noise removal, Shape removal (4th order) <Calculation Conditions>

[0146]

[0147]

[0148] In the formula, A represents the measurement area, Z(x, y) represents the height data from the mean plane (the mean plane is the average value of all measurement data), Sa represents the average of the absolute values ​​of the height data, and Sv represents the absolute value of the minimum height data.

[0149] (7) Center Line Average Roughness (Ra) Using the episulfide-based resin substrate (second layer) prepared in (1) above, line roughness measurement was carried out under the following conditions. For the episulfide-based resin substrate (second layer) (sample) for which the surface roughness in (6) above was measured, measurements were carried out at three locations at 1 / 4 intervals on the measurement screen. The average of the obtained measured values ​​was taken as the center line average roughness (Ra), and is shown in Table 1.

[0150]

[0151] (8) Luminous transmittance when bleached, luminous transmittance when colored, 555 nm light transmittance Using an instantaneous multi-photometering system MSPD-7700 manufactured by Otsuka Electronics equipped with an excitation light source xenon lamp MS-35AAA / FB2000-O manufactured by Ushio Electric Co., Ltd., the spectral transmittance (% T; 400 nm - 780 nm) of the optical element was measured at 23 ° C., and the light transmittance at 555 nm was obtained. Based on ISO 8980-3, the luminous transmittance (% T; 400 nm - 780 nm) when bleached was calculated. Then, the optical element was irradiated with excitation light for 15 minutes under conditions of a temperature of 23 ° C. and an illuminance of 50,000 lux. The spectral transmittance after 15 minutes was measured, and the light transmittance at 555 nm was obtained. Then, based on ISO 8980-3, the luminous transmittance when colored was calculated. The results are shown in Table 1.

[0152] (9) Haze Value The haze value of the obtained optical member was measured using a haze meter (model: NDH 2000) manufactured by Nippon Denshoku Industries Co., Ltd. The results are shown in Table 1.

[0153] (10) Evaluation of Adhesion The blade of a steel wedge (model number: W-S-1.5, blade length 70.5 mm, total length 230 mm) was placed between the episulfide resin substrate (second layer) and the photochromic functional layer (first layer) of the obtained optical component, and the steel wedge was manually hammered into the optical component using a metal hammer until it broke, and the evaluation was performed. The less exposed the interlayer (interface) was, the better the adhesion. The results are shown in Table 1.

[0154] (11) Evaluation of Appearance The obtained optical element was placed on a piece of paper with written characters, and visually observed and evaluated according to the following criteria: Criteria Transparent: The characters written on the paper were clearly visible Opaque: The characters written on the paper were cloudy or blurred and were not clearly visible

[0155] (12) Evaluation of Photochromic Function It was confirmed that the optical elements of Examples 1 to 4 exhibited better color development performance more quickly than the optical elements of Comparative Examples 1 and 2 when placed under sunlight, and quickly returned to a transparent state when returned indoors.

[0156]

[0157] This application claims priority based on Japanese Patent Application No. 2024-129718, filed August 6, 2024, the disclosure of which is incorporated herein by reference in its entirety.

[0158] 11 First layer 11a surface 11b surface 20 Gap 21 Second layer 21a surface 21b surface S Interface 30 Substrate 31 Fixing member 100 Optical member

Claims

1. An optical component comprising: a first layer made of a cured product of a first polymerizable composition; and a second layer made of a cured product of a second polymerizable composition, the second layer being thicker than the first layer and disposed in contact with the first layer; wherein, at the interface between the first and second layers, when the first layer side is a peak and the second layer side is a valley, the arithmetic mean height Sa, as determined in accordance with ISO 4287-1997, is 0.01 to 0.15 μm and the maximum valley depth Sv is 0.20 to 2.00 μm; and the refractive index is 1.40 or more and 2.00 or less.

2. An optical element comprising: a first layer made of a cured product of a first polymerizable composition; and a second layer made of a cured product of a second polymerizable composition, the second layer being thicker than the first layer and disposed in contact with the first layer; wherein, at the interface between the first layer and the second layer, when the first layer side is the peak and the second layer side is the valley, the center line average roughness Ra, as determined in accordance with JIS B 0601-2001, is 0.010 to 0.100 μm; and the refractive index is 1.40 or more and 2.00 or less.

3. An optical element according to claim 1 or 2, wherein the first layer or the second layer contains one or more resins selected from the group consisting of polycarbonate-based resins, (meth)acrylic-based resins, epoxy-based resins, urethane-based resins, episulfide-based resins, and thiourethane-based resins.

4. An optical element according to claim 1 or 2, wherein the first polymerizable composition and the second polymerizable composition have different compositions.

5. An optical member according to claim 1 or 2, wherein the second layer contains an episulfide-based resin.

6. An optical element according to claim 1 or 2, wherein the first layer contains a pigment.

7. An optical element according to claim 1 or 2, wherein the first layer contains a photochromic dye.

8. An optical member according to claim 1 or 2, wherein the first polymerizable composition contains a polyol compound.

9. An optical element according to claim 8, wherein the polyol compound comprises one or more compounds selected from the group consisting of a linear or branched aliphatic polyol (i), an alicyclic polyol (ii), and a polyether polyol (iii).

10. An optical element according to claim 1 or 2, wherein the first layer has an average thickness of 0.1 mm to 5 mm.

11. An optical element according to claim 1 or 2, wherein the average thickness of the second layer is 0.5 mm to 20 mm.

12. An optical element according to claim 1 or 2, wherein the refractive index of the first layer is 1.50 to 1.

67.

13. An optical element according to claim 1 or 2, wherein the absolute value of the difference between the refractive index of the first layer and the refractive index of the second layer is 0.45 or less.

14. The optical element according to claim 1 or 2, wherein the haze value according to JIS K7136 is 1% or more and 40% or less.

15. The optical element according to claim 1 or 2, wherein the transmittance of light at a wavelength of 555 nm is 3 to 97%.

16. An optical lens comprising the optical member according to claim 1 or 2.

17. A photochromic lens comprising the optical element according to claim 1 or 2.

18. A method for producing an optical element comprising: a first layer made of a cured product of a first polymerizable composition; and a second layer made of a cured product of a second polymerizable composition, the second layer being thicker than the first layer and in contact with the first layer; the method comprising: curing the second polymerizable composition to form the second layer; polishing at least one surface of the second layer so that the arithmetic mean height Sa, determined in accordance with ISO 4287-1997, is 0.01 to 0.15 μm and the maximum valley depth Sv is 0.20 to 2.00 μm; and forming the first layer made of the cured product of the first polymerizable composition on the polished surface of the second layer; wherein the refractive index of the optical element is 1.40 or more and 2.00 or less.

19. A method for producing an optical element according to claim 18, wherein the first layer or the second layer contains one or more resins selected from the group consisting of polycarbonate-based resins, (meth)acrylic-based resins, epoxy-based resins, urethane-based resins, episulfide-based resins, and thiourethane-based resins.

20. The method for producing an optical member according to claim 18 or 19, wherein the first polymerizable composition and the second polymerizable composition have different compositions.

21. A method for producing an optical member according to claim 18 or 19, wherein the second layer contains an episulfide-based resin.

22. A method for manufacturing an optical element according to claim 18 or 19, wherein in the polishing step, polishing is carried out using an abrasive having an average particle size of 5 to 15 μm.

23. A method for manufacturing an optical element according to claim 18 or 19, wherein in the polishing step, polishing is carried out using an abrasive consisting of one or more abrasives selected from the group consisting of alumina, diamond powder, boron nitride, cerium oxide, and zirconium oxide.

24. A method for manufacturing an optical member according to claim 18 or 19, comprising the step of cleaning the second layer after the polishing step and before the step of forming the first layer.

25. A method for manufacturing an optical element according to claim 18 or 19, wherein in the step of forming the first layer, the first layer is formed by laminating a film made of a first polymerizable composition onto the polished surface of the second layer and then curing it, or by injecting the first polymerizable composition into a mold in which the second layer has been placed and then curing it.

26. A method for producing an optical member according to claim 18 or 19, wherein the first polymerizable composition contains a photochromic dye.

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