Composite membrane

Abstract

The present invention provides a composite film excellent in adhesion between layers. A composite film according to an embodiment of the present invention includes a first polymer part including a first polymer, and a second polymer part disposed in direct contact with at least a portion of the first polymer part and including a second polymer, wherein each of the first polymer and the second polymer includes a constituent unit derived from a siloxane monomer, the second polymer (i) not including a constituent unit derived from a siloxane monomer containing a nitrogen atom, or (ii) including a constituent unit derived from a siloxane monomer containing a nitrogen atom, and in the case of (ii), the second polymer including 4 wt% or more of a constituent unit derived from a monofunctional monomer having a molecular weight of 500 or less and not containing a nitrogen atom.

Description

composite membrane

[0001] The present invention relates to composite membranes, and more particularly to composite membranes applicable to ophthalmic devices.

[0002] Contact lenses are generally broadly classified into hard contact lenses, which are made of relatively hard materials, and soft contact lenses, which are made of relatively soft materials. In recent years, hybrid lenses that combine two or more materials, such as a soft contact lens material and a hard contact lens material, or a soft contact lens material A and a soft contact lens material B, have been studied in order to impart desired properties to contact lenses (see, for example, Patent Document 1). Research is also underway on smart contact lenses, which incorporate electronic components inside the lens (see, for example, Patent Document 2).

[0003] US Patent Application Publication No. 2007 / 0291224 JP 2016-46256 A

[0004] Contact lenses with a laminated structure, such as those found in hybrid lenses and smart contact lenses, require high adhesion between layers. Specifically, if delamination or lifting occurs during use, concerns arise about a foreign body sensation, eye irritation, lens fogging due to tear fluid penetration, and the growth of bacteria. Furthermore, with smart contact lenses, concerns exist about electric shock due to exposed electronic components and the leakage of harmful substances.

[0005] A primary object of the present invention is to provide a composite membrane having excellent adhesion between different materials, for example, a composite membrane having excellent interlayer adhesion between two or more layers containing different polymer materials.

[0006] [1] According to one aspect of the present invention, there is provided a composite membrane comprising a first polymer portion containing a first polymer and a second polymer portion disposed in direct contact with at least a portion of the first polymer portion, the first polymer and the second polymer each containing a structural unit derived from a siloxane monomer, with the proviso that the second polymer either (i) does not contain a structural unit derived from a siloxane monomer containing a nitrogen atom, or (ii) contains a structural unit derived from a siloxane monomer containing a nitrogen atom, and in the case of (ii), the second polymer has a molecular weight of 500 or less and contains 4 wt% or more structural units derived from a monofunctional monomer not containing a nitrogen atom. [2] In the composite membrane described in [1] above, the first polymer portion may be a first polymer layer having a front surface and a back surface, and the second polymer portion may be a second polymer layer disposed in direct contact with at least a portion of one surface of the first polymer layer. [3] The composite membrane described in [2] above may have a laminate structure in which two or more polymer layers are laminated. [4] In the composite film described in [2] or [3] above, the second polymer layer may be disposed in direct contact with at least a portion of the back surface of the first polymer layer. [5] The composite film described in any of [2] to [4] above may further include a third polymer layer disposed in direct contact with at least a portion of the surface of the second polymer layer opposite the first polymer layer, the third polymer including a structural unit derived from a siloxane monomer. [6] The composite film described in any of [1] to [5] above may have an oxygen permeability coefficient of 50 Barrers or more. [7] The composite film described in any of [1] to [6] above may have a total light transmittance of 80% or more. [8] In the composite film described in any of [1] to [7] above, the water absorption of each polymer portion may be 3 wt% or less. [9] In the composite film described in any of [2] to [8] above, at least one outermost layer may have a Rockwell superficial hardness of 20 or more.

[10] In the composite film described in any one of [1] to [9] above, the first polymer and / or the second polymer may contain, as the siloxane monomer-derived structural unit, a structural unit derived from a long-chain siloxane monomer having a siloxane bond with a repeat number of 3 or more.

[11] In the composite film described in

[10] above, the total number of siloxane bonds in the long-chain siloxane monomer may be 100 or less.

[12] In the composite film described in

[10] or

[11] above, the second polymer may contain the long-chain siloxane monomer-derived structural unit.

[13] In the composite film described in any one of [1] to

[12] above, the first polymer may contain the siloxane monomer-derived structural unit in a content of 80 wt% or less.

[14] In the composite film described in any one of [1] to

[13] above, the first polymer may contain, as the siloxane monomer-derived structural unit, a structural unit derived from a siloxane-containing styrene derivative.

[15] The composite film according to any one of [1] to

[14] above may be an ophthalmic device.

[16] The composite film according to any one of [1] to

[14] above may be an intraocular lens.

[17] The composite film according to any one of [1] to

[14] above may be a contact lens.

[18] The composite film according to any one of [1] to

[14] above may be an orthokeratology lens.

[19] The composite film according to any one of [1] to

[14] above may be a hybrid lens comprising a hard contact lens portion and a soft contact lens portion.

[20] In the composite film according to

[19] above, the first polymer portion may be the hard contact lens portion.

[21] The composite film according to any one of [1] to

[20] above may have a functional element embedded therein.

[0007] According to an embodiment of the present invention, in a composite film including a first polymer portion and a second polymer portion, both of which contain a polymer obtained using a siloxane monomer, the second polymer portion can include a polymer obtained without using a siloxane monomer containing a nitrogen atom, or a polymer obtained by using a siloxane monomer containing a nitrogen atom together with a predetermined monofunctional monomer blended at a predetermined content ratio, thereby improving adhesion between the polymer portions.

[0008] FIG. 1(a) is a schematic plan view of a composite membrane according to one embodiment of the present invention, and FIG. 1(b) is a schematic cross-sectional view taken along line A-A thereof. ...b) is a schematic diagram illustrating an example of a method for producing a composite membrane according to an embodiment of the present invention. FIG. 1(b) is a schematic diagram illustrating an example of a method for producing a composite membrane according to an embodiment of the present invention.

[0009] 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.

[0010] 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, or an allyl group. Here, "(meth)" means an optional methyl substitution. Therefore, "(meth)acryloyl" means methacryloyl and / or acryloyl. The same applies to other descriptions such as "(meth)acrylic."

[0011] In this specification, when it is said that "Layer A is in direct contact with Layer B," it means that Layer A and Layer B are in close contact with each other without any gaps between them and without any other layer such as an adhesive layer being interposed therebetween.

[0012] A. Composite Membrane A composite membrane according to an embodiment of the present invention includes a first polymer portion containing a first polymer and a second polymer portion disposed in direct contact with at least a portion of the first polymer portion and containing a second polymer. Typically, the first polymer and the second polymer each contain structural units derived from siloxane monomers, with the proviso that the second polymer either (i) does not contain structural units derived from siloxane monomers containing nitrogen atoms, or (ii) contains structural units derived from siloxane monomers containing nitrogen atoms. In the case of (ii), the second polymer has a molecular weight of 500 or less and contains 4 wt. % or more structural units derived from monofunctional monomers that do not contain nitrogen atoms. As described below, composite membranes according to embodiments of the present invention can be used as ophthalmic lenses, such as contact lenses. Therefore, the composite membrane can have a hemispherical shape that follows the curve of the cornea. Furthermore, with regard to a composite membrane, the side that contacts the eye when used as an ophthalmic lens may be referred to as the back side, and the opposite side as the front side.

[0013] In one embodiment, the composite membrane may be a multilayer membrane including a first polymer layer having a front surface and a back surface and including a first polymer, and a second polymer layer disposed in direct contact with at least a portion of one surface of the first polymer layer and including a second polymer.

[0014] Fig. 1(a) is a schematic plan view of a composite membrane (multilayer membrane) according to one embodiment of the present invention, (b) is a schematic cross-sectional view taken along line A-A thereof, and Fig. 2(a) is a schematic plan view of a composite membrane (multilayer membrane) according to another embodiment of the present invention, (b) is a schematic cross-sectional view taken along line A-A thereof.

[0015] The multilayer film 100A shown in FIG. 1 includes a first polymer layer 10 having a front surface 10a and a back surface 10b, and a second polymer layer 20 disposed in direct contact with the back surface 10b of the first polymer layer 10. The size of the multilayer film 100A can be appropriately set depending on the application. The maximum diameter of the multilayer film 100A is, for example, 12.5 mm to 22 mm. The center thickness of the first polymer layer 10 can be, for example, 0.05 mm to 0.2 mm, or, for example, 0.1 mm to 0.2 mm. The center thickness of the second polymer layer 20 can be, for example, 0.5 mm to 1.2 mm, or, for example, 0.7 mm to 1.1 mm.

[0016] The multilayer film 100B shown in FIG. 2 includes a first polymer layer 10 having a front surface 10a and a back surface 10b, a second polymer layer 20 disposed in direct contact with the back surface 10b of the first polymer layer 10, and a third polymer layer 30 disposed in direct contact with the back surface of the second polymer layer 20. The maximum diameter of the multilayer film 100B is, for example, 12.5 mm to 22 mm. The center thickness of the first polymer layer 10 can be, for example, 0.05 mm to 0.2 mm, or for example, 0.1 mm to 0.2 mm. The center thickness of the second polymer layer 20 can be, for example, 0.5 mm to 1.2 mm, or for example, 0.7 mm to 1.1 mm. The center thickness of the third polymer layer 30 can be, for example, 0.05 mm to 0.2 mm, or for example, 0.1 mm to 0.2 mm.

[0017] The structure of the composite membrane according to the embodiment of the present invention is not limited to the illustrated example. The multilayer membrane may have, for example, a two-layer structure in which a second polymer layer is disposed in direct contact with at least a portion of the front surface of a first polymer layer, or a three-layer structure in which a second polymer layer is disposed in direct contact with at least a portion of one surface of a first polymer layer and a third polymer layer is disposed in direct contact with at least a portion of the other surface of a first polymer layer. The multilayer membrane may also include four or more polymer layers. Furthermore, each polymer layer does not need to be in full contact with the adjacent layer, as long as at least a portion of the polymer layer is in contact. For example, the multilayer membrane may have a structure in which a first polymer layer is disposed in direct contact with the central region of the second polymer layer. In the structure shown in FIG. 1, the diameter of the first polymer layer may be smaller than the diameter of the second polymer layer. Alternatively, the composite membrane may have a structure in which polymer portions, each having a front surface and a back surface, are arranged in a multiple circular pattern in plan view. For example, the composite membrane 100C shown in FIG. 3 includes a second polymer portion 20 that is circular in plan view and a first polymer portion 10 that is disposed in direct contact with the second polymer portion 20 and surrounds its outer peripheral edge. Unlike the illustrated example, the second polymer portion may be disposed in direct contact with the outer peripheral end face of the first polymer portion so as to surround the outer peripheral end face.

[0018] The following description will be made specifically with respect to an embodiment in which the composite membrane is a multilayer membrane, but the following description can also be applied to composite membranes having structures other than multilayer membranes unless the context clearly indicates otherwise.

[0019] The above multilayer film can have high oxygen permeability because both the first polymer and the second polymer contain structural units derived from siloxane monomers. The oxygen permeability coefficient (Dk value) of the multilayer film is, for example, 50 Barrer or more, preferably 100 Barrer or more, and more preferably 150 Barrer or more. A multilayer film having the above oxygen permeability coefficient can supply sufficient oxygen to the cornea when used as a contact lens. The upper limit of the oxygen permeability coefficient to the cornea is not particularly limited, but can be, for example, 600 Barrer or less. The oxygen permeability coefficient can be determined by the method described in the Examples. The unit of oxygen permeability coefficient, "Barrer," is expressed as "×10－１１ (cm ２ / sec)・(mLO ２ / (mL×mmHg)).

[0020] In one embodiment, the Rockwell superficial hardness of at least one outermost layer of the multilayer film is, for example, 20 or more, preferably 30 or more, and more preferably 40 or more. A multilayer film in which the Rockwell superficial hardness of one outermost layer, preferably both outermost layers, is within the above range can have high mechanical stability and excellent handleability. The upper limit of the Rockwell superficial hardness is not particularly limited, but can be, for example, 150 or less.

[0021] In one embodiment, the water absorption (moisture content) of each layer constituting the multilayer film (and consequently the water absorption of the entire multilayer film) is typically less than 10 wt%, for example, 3 wt% or less, preferably 2 wt% or less, more preferably 1 wt% or less, and even more preferably 0.5 wt% or less. The lower limit of the water absorption is not particularly limited, and the water absorption can be, for example, 0.1 wt% or less. The water absorption can be determined by the method described in the Examples.

[0022] The total light transmittance of the multilayer film is, for example, 80% or more, preferably 90% or more, and more preferably 95% or more. When the total light transmittance of the multilayer film is within the above range, it is suitable for use as an ophthalmic device. The total light transmittance can be measured in accordance with JIS K 7361.

[0023] <First Polymer Layer> The first polymer layer includes a first polymer containing a structural unit derived from a siloxane monomer. The first polymer layer is substantially composed of the first polymer. Specifically, the content of the first polymer in the first polymer layer in a water-saturated state is typically more than 90 wt %, for example, 95 wt % or more, and may be 97 wt % or more or 98 wt % or more, and for example, 99.95 wt % or less, or may be 99.9 wt % or less.

[0024] The water absorption of the first polymer layer is typically less than 10% by weight, for example, 3% by weight or less, preferably 2% by weight or less, more preferably 1% by weight or less, and even more preferably 0.5% by weight or less. The lower limit of the water absorption is not particularly limited, and the water absorption can be, for example, 0.1% by weight or less.

[0025] By including a structural unit derived from a siloxane monomer in the first polymer, the first polymer layer can have high oxygen permeability. The oxygen permeability coefficient of the first polymer layer is, for example, 50 Barrer or more, preferably 100 Barrer or more, and more preferably 150 Barrer or more. A multilayer film in which the first polymer layer has the above oxygen permeability coefficient can supply sufficient oxygen to the cornea when used as a contact lens. The upper limit of the oxygen permeability coefficient is not particularly limited, but can be, for example, 600 Barrer or less.

[0026] The Rockwell superficial hardness of the first polymer layer is, for example, 20 or more, preferably 30 or more, and more preferably 40 or more. When the Rockwell superficial hardness of the first polymer layer is within the above range, a multilayer film excellent in processability (e.g., lathability) and handleability can be obtained. Furthermore, a first polymer layer having such a hardness can function as a hard contact lens layer. The upper limit of the Rockwell superficial hardness is not particularly limited, but can be, for example, 150 or less.

[0027] The tensile modulus of the first polymer layer is, for example, 50 MPa or more, preferably 100 MPa or more, and more preferably 200 MPa or more. When the tensile modulus of the first polymer layer is within the above range, a multilayer film with high mechanical stability and excellent handleability can be obtained. Furthermore, a first polymer layer having such a tensile modulus can function as a hard contact lens layer. The upper limit of the tensile modulus is not particularly limited, but may be, for example, 3000 MPa or less, or 2000 MPa or less. The tensile modulus can be calculated from the stress-elongation curve, for example, by conducting a tensile test on a dumbbell-shaped test sample with a stretched portion width of approximately 2 mm and a thickness of approximately 0.7 mm in physiological saline at 20°C at a stretching rate of 100 mm / min.

[0028] The total light transmittance of the first polymer layer is, for example, 80% or more, preferably 90% or more, and more preferably 95% or more. When the total light transmittance of the first polymer layer is within the above range, a highly transparent multilayer film can be obtained.

[0029] In one embodiment, the surface of the first polymer layer that does not come into contact with the second polymer layer may be subjected to a surface modification treatment such as corona treatment or plasma treatment. The surface modification treatment improves wettability, resulting in good compatibility with lacrimal fluid and an excellent wearing comfort. The contact angle of the surface of the first polymer layer after the surface modification treatment is, for example, 90° or less, preferably 70° or less, and more preferably 0° to 50°.

[0030] The dynamic friction coefficient of the surface of the first polymer layer can be, for example, 0.1 to 2.0, or, for example, 0.2 to 1.5. A multilayer film in which a first polymer layer having the above dynamic friction coefficient is disposed on the front surface of a second polymer layer that tends to have a high dynamic friction coefficient can reduce friction with the eyelid when used as a contact lens, thereby providing a comfortable fit.

[0031] The first polymer is obtained by polymerizing a polymerizable composition containing a monomer component, and contains structural units derived from each monomer in the monomer component. As the first polymer, a polymer containing structural units derived from a siloxane monomer and satisfying the above-mentioned properties can be preferably used. In this specification, the content ratio of the structural units derived from each monomer in the polymer is considered to correspond to the content ratio of each monomer in the monomer component.

[0032] As described above, the monomer component includes a siloxane monomer. The siloxane monomer has one or more siloxane bonds (Si—O—Si) and a polymerizable group in the molecule. The monomer component typically further includes a monomer other than the siloxane monomer (in other words, a monomer that does not have a siloxane bond in the molecule). Such monomers include copolymerizable monomers (monofunctional monomers) such as hydrophobic monomers and hydrophilic monomers, and crosslinkable monomers (polyfunctional monomers). The monomer component may be composed of a siloxane monomer and one or more monomers selected from copolymerizable monomers and crosslinkable monomers. The total content of the siloxane monomer, hydrophobic monomer, hydrophilic monomer, and crosslinkable monomer in the monomer component may be, for example, 95% to 100% by weight, or, for example, 97% to 99.9999% by weight. From the viewpoint of improving adhesion to the second polymer layer, the content of the nitrogen atom-containing monomer in the monomer components is preferably 50% by weight or less, more preferably 0% by weight to 40% by weight, even more preferably 0% by weight to 20% by weight, and may be, for example, 0% by weight to 10% by weight.

[0033] Any appropriate monomer may be used as the siloxane monomer as long as it has a siloxane bond and a polymerizable group. Due to the presence of the siloxane bond, the siloxane monomer can impart high oxygen permeability to the polymer material. In one embodiment, the siloxane monomer may be a non-crosslinkable siloxane monomer having a single polymerizable group (in other words, having only one polymerizable group in the molecule). In another embodiment, the siloxane monomer may be a crosslinkable siloxane monomer having two or more polymerizable groups in the molecule. From the viewpoint of interlayer adhesion, it is preferable to use a siloxane monomer that does not contain a nitrogen atom. When a siloxane monomer containing a nitrogen atom is used, its content is as described above. In the embodiment of the present invention, only one type of siloxane monomer may be used, or two or more types may be used in combination.

[0034] The number of siloxane bonds contained in the siloxane monomer is not limited as long as the effects of the present invention are obtained, and may be, for example, 1 or more, 2 or more, or 3 or more, and may be, for example, 100 or less, 80 or less, or 60 or less. The number of siloxane bonds does not refer to the number of repetitions of siloxane bonds in one chain, but refers to the total number of all siloxane bonds in the molecule. In this specification, a siloxane monomer containing 3 or more repetitions of siloxane bonds in one chain, whether in the main chain or side chain, may be referred to as a long-chain siloxane monomer. Furthermore, a monomer with an average molecular weight (Mw) of more than 1,000 may be referred to as a macromonomer. The average molecular weight (Mw) can be determined in polystyrene equivalent terms by SEC measurement.

[0035] 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-A No. 2015-503631, the siloxane monomers described in paragraphs 0060 to 0065 of JP-A No. 2014-40598, and the siloxane monomers described in paragraphs 0024 to 0037 of WO 2015 / 92858 (specifically, siloxane monomers represented by the following formula (A), preferably formula (A-1), (A-2), or (A-3)). These publications are incorporated herein by reference in their entirety.

[0036] In the above general formula (A), 1) n is 0 or an integer of 1 to 10. 2) A １ and A ２ are groups represented by the following general formulae (A-II) and (A-III), respectively. In the following general formulae (A-II) and (A-III), Y ２１ and Y ２２ are each independently an acryloyloxy group, a methacryloyloxy group, a vinyl group, or an allyl group, and R ２１ and R ２２ are each independently a direct bond or a linear or branched alkylene group having 2 to 6 carbon atoms. ２１ -R ２１ -...(A-II) -R ２２ -Y ２２ ...(A-III) 3) Z １ , Z ２ , Z ３ , Z ４ , Z ５ and Z ６ are each independently a direct bond or a polyalkylene glycol chain having an alkylene glycol (oxyalkylene group) as a repeating unit. １ ~Z ６ At least one of the Z １ ~Z ６At least one of the above is a polyalkylene glycol chain having an alkylene glycol other than ethylene glycol as a repeating unit (for example, a polypropylene glycol chain having propylene glycol as a constituent unit, specifically a polypropylene glycol chain having 5 to 16 repeating units of propylene glycol). １ is a group represented by the following general formula (A-IV), which contains a urethane bond in the molecular chain of the siloxane monomer. ２１ is a -NHCO- group (in this case, E ２１ is X ２１ and forming a urethane bond), or a divalent group derived from a diisocyanate selected from the group consisting of saturated or unsaturated aliphatic, alicyclic and aromatic diisocyanates (in this case, E ２１ is Z １ and X ２１ A urethane bond is formed between X ２１ is an oxygen atom. ２１ -X ２１ - ... (A-IV) 5) U ２ is a group represented by the following general formula (A-VI), which contains a urethane bond in the molecular chain of the siloxane monomer. ４１ and R ４２ are each independently a linear or branched alkylene group having 2 to 6 carbon atoms; X ４１ and X ４２ are each independently an oxygen atom or an alkylene glycol group, E ４１ is a divalent group derived from a diisocyanate selected from the group consisting of saturated or unsaturated aliphatic, alicyclic and aromatic diisocyanates (in this case, E ４１ is X ４１ and X ４２ -R forms a urethane bond between them. ４１ -X ４１ -E ４１ -X ４２ -R ４２ - ... (A-VI) 6) U ３is a group represented by the following general formula (A-VII), which contains a urethane bond in the molecular chain of the siloxane monomer. ２２ is an oxygen atom, and E ２２ is a -NHCO- group (in this case, E ２２ is X ２２ or a divalent group derived from a diisocyanate selected from the group consisting of saturated or unsaturated aliphatic, alicyclic and aromatic diisocyanates (in this case, E ２２ is Z ５ and X ２２ -X forms a urethane bond. ２２ -E ２２ -...(A-VII) 7)S １ and S ２ are each independently a group represented by the following general formula (AV): ３１ and R ３８ are each independently a linear or branched alkylene group having 2 to 6 carbon atoms, and R ３２ , R ３３ , R ３４ , R ３５ , R ３６ and R ３７ are each independently an alkyl group having 1 to 6 carbon atoms, a fluorine-substituted alkyl group, or a phenyl group. K is an integer of 1 to 1500, L is 0 or an integer of 1 to 1500, and the sum of K and L (K+L) is, for example, an integer of 1 to 1500, preferably an integer of 2 to 1000, and more preferably an integer of 3 to 500.

[0037] (In the above formula, R ５１ represents a hydrogen atom or a methyl group, a is an integer of 2 or more, b is an integer of 2 or more, and n is an integer of 1 to 1500. ５２ and R ５３ is a hydrogen atom or a methyl group, and R ５２ is a hydrogen atom, R ５３ is a methyl group, and R ５２ When is a methyl group, R ５３is a hydrogen atom.)

[0038] (In the above formula, a' is an integer of 2 or more, b' is an integer of 2 or more, and n' is an integer of 1 to 1500. ６１ and R ６２ is a hydrogen atom or a methyl group, and R ６１ is a hydrogen atom, R ６２ is a methyl group, and R ６１ When is a methyl group, R ６２ is a hydrogen atom.)

[0039] (In the above formula, a" is an integer of 2 or more, b" is an integer of 2 or more, and n" is an integer of 1 to 1500. ８１ and R ８２ is a hydrogen atom or a methyl group, and R ８１ is a hydrogen atom, R ８２ is a methyl group, and R ８１ When is a methyl group, R ８２ is a hydrogen atom.)

[0040] 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.

[0041] 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.

[0042] The content of the siloxane monomer in the monomer component (in other words, the content of the siloxane monomer-derived structural unit in the first polymer) is, for example, 10% by weight or more, preferably 20% by weight or more, more preferably 30% by weight or more, and for example, 80% by weight or less, preferably 70% by weight or less, more preferably 60% by weight or less. When the content of the siloxane monomer is within the above range, a multilayer film with excellent oxygen permeability can be obtained.

[0043] Examples of hydrophobic monomers include alkyl (meth)acrylates, fluorine-containing alkyl (meth)acrylates, aromatic ring-containing (meth)acrylates, and styrene-based monomers. The hydrophobic monomers may be used singly or in combination. The solubility of the hydrophobic monomer in water at 25°C may be, for example, less than 0.03 g / mL.

[0044] 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, etc. Among these, those with a large fluorine moiety are preferred from the viewpoint of obtaining a multilayer film having superior oxygen permeability and antifouling properties.Specifically, (perfluorohexyl)ethyl (meth)acrylate, (perfluorooctyl)ethyl (meth)acrylate, (perfluorodecyl)ethyl (meth)acrylate, etc. are preferred, and (perfluorooctyl)ethyl (meth)acrylate is more preferred from the viewpoint of easy availability and ease of purification. 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.

[0045] The content of the hydrophobic monomer in the monomer components (in other words, the content of structural units derived from the hydrophobic monomer in the first polymer) is, for example, 5 to 90% by weight, preferably 10 to 80% by weight, and more preferably 10 to 70% by weight. By using the hydrophobic monomer in this content, it is easy to adjust the properties of the first polymer (for example, water absorption).

[0046] Examples of hydrophilic monomers include polar group-containing monomers such as hydroxyl group-containing monomers, carboxyl group-containing monomers, nitrogen atom-containing monomers, and alkoxyl group-containing monomers. The hydrophilic monomers may be used singly or in combination. The solubility of the hydrophilic monomer in water at 25°C may be, for example, 0.03 g / mL or more.

[0047] 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. 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.

[0048] The content of the hydrophilic monomer in the monomer component (in other words, the content of structural units derived from the hydrophilic monomer in the first polymer) is, for example, 80% by weight or less, preferably 0 to 70% by weight, and more preferably 0 to 60% by weight (e.g., 0 to 20% by weight, 0 to 10% by weight, or 0 to 5% by weight). By having the content of the hydrophilic monomer within the above range, a polymer having the desired hydrophilicity can be suitably obtained.

[0049] The crosslinking monomer contains two or more polymerizable functional groups (excluding those corresponding to siloxane monomers). By using the crosslinking monomer, a multilayer film having desired flexibility and mechanical strength can be suitably obtained. The crosslinking monomer can be used alone or in combination of two or more.

[0050] 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 first polymer can be adjusted.

[0051] The content of the crosslinkable monomer in the monomer component (in other words, the content of structural units derived from the crosslinkable monomer in the first polymer) is, for example, 0 to 25% by weight, preferably 0.1 to 20% by weight, more preferably 0.5 to 15% by weight, such as 5 to 15% by weight, or 10 to 15% by weight. When the content of the crosslinkable monomer is within the above range, the flexibility and mechanical strength of the first polymer can be suitably adjusted.

[0052] 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, and crosslinkable monomer.

[0053] The total content of functional monomers in the monomer components (in other words, the total content of structural units derived from functional monomers in the first polymer) 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.

[0054] The first polymer layer may further contain any suitable additive, if necessary. Examples of the additive include additives conventionally used in ophthalmic devices. Examples include a cooling agent, a thickening agent, a surfactant, a non-polymerizable dye, and a non-polymerizable ultraviolet absorber.

[0055] The amount of the additive in the first polymer layer 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 first polymer.

[0056] The polymerizable composition and the polymerization method will be described in detail in Section C.

[0057] <Second Polymer Layer> The second polymer layer includes a second polymer containing structural units derived from a siloxane monomer. The second polymer layer is substantially composed of the second polymer. Specifically, the content of the second polymer in the second polymer layer in a water-saturated state is typically more than 90 wt %, for example, 95 wt % or more, and may be 97 wt % or more or 98 wt % or more, and may be, for example, 99.95 wt % or less, or 99.9 wt % or less.

[0058] The water absorption of the second polymer layer is, for example, less than 10% by weight, preferably 5% by weight or less, more preferably 3% by weight or less, and even more preferably 2% by weight or less. The lower limit of the water absorption is not particularly limited, and the water absorption can be, for example, 0.1% by weight or less.

[0059] The second polymer contains a structural unit derived from a siloxane monomer, which allows the second polymer layer to have high oxygen permeability. The oxygen permeability coefficient of the second polymer layer is, for example, 200 Barrer or more, preferably 300 Barrer or more, and more preferably 400 Barrer or more. When the multilayer film in which the second polymer layer has the above oxygen permeability coefficient is used as a contact lens, it can reduce eye strain and provide an excellent wearing comfort. The upper limit of the oxygen permeability coefficient is not particularly limited, but can be, for example, 1000 Barrer or less.

[0060] In one embodiment, the difference between the oxygen permeability of the first polymer layer and the oxygen permeability of the second polymer layer (Dk value of the second polymer layer - Dk value of the first polymer layer) is, for example, 40 Barrer or more, and may be 50 Barrer to 1000 Barrer. By having the second polymer layer have extremely high oxygen permeability, even when the second polymer layer has a thickness that allows a functional element to be encapsulated therein, the multilayer film as a whole can maintain practical oxygen permeability.

[0061] The tensile modulus of the second polymer layer is, for example, 1000 MPa or less, preferably 500 MPa or less, and more preferably 400 MPa or less. When the tensile modulus of the second polymer layer is within the above range, a multilayer film that provides excellent wearing comfort when used as an ophthalmic lens can be obtained. Furthermore, a second polymer layer having such a tensile modulus can function as a soft contact lens layer. The lower limit of the tensile modulus is not particularly limited, but may be, for example, 0.05 MPa or more, or, for example, 0.1 MPa or more. In one embodiment, the tensile modulus of the second polymer layer is lower than that of the first polymer layer. The tensile modulus can be calculated, for example, by conducting a tensile test using a dumbbell-shaped test sample (e.g., a dumbbell-shaped test sample having a stretched portion width of approximately 2 mm and a thickness of approximately 0.75 mm) in physiological saline at 20°C or at room temperature at a stretching rate of 2 mm / min to 100 mm / min, and then calculating the tensile modulus from the stress-elongation curve.

[0062] The total light transmittance of the second polymer layer is, for example, 80% or more, preferably 90% or more, and more preferably 95% or more. When the total light transmittance of the second polymer layer is within the above range, a highly transparent multilayer film can be obtained.

[0063] The contact angle of the surface of the second polymer layer opposite to the side in contact with the first polymer layer is, for example, 60° to 130°, preferably 70° to 120°, and more preferably 80° to 110°. The difference between the contact angle of the surface of the first polymer layer in contact with the second polymer layer and the contact angle of the surface of the second polymer layer opposite to the side in contact with the first polymer layer (latter - former) may be, for example, 30° or more, 40° or more, 50° or more, or 60° or more.

[0064] The dynamic friction coefficient of the surface of the second polymer layer is, for example, 0.2 to 20, or, for example, 1.0 to 15. A multilayer film in which a first polymer layer having a lower dynamic friction coefficient is disposed on the front surface of a second polymer layer having the above dynamic friction coefficient reduces friction with the eyelids when used as a contact lens, and a comfortable fit can be achieved.

[0065] The second polymer preferably contains structural units derived from siloxane monomers and satisfies the above-described characteristics. The second polymer is obtained by polymerizing a polymerizable composition containing monomer components, and contains structural units derived from each monomer in the monomer components. Typically, the first polymer and the second polymer are different polymer materials, and the types and / or content ratios of the structural units are different.

[0066] In one embodiment, the second polymer does not contain any constitutional units derived from siloxane monomers containing nitrogen atoms. In another embodiment, the second polymer contains constitutional units derived from siloxane monomers containing nitrogen atoms, and further contains 4% by weight or more constitutional units derived from monofunctional monomers that do not contain nitrogen atoms and have a molecular weight of 500 or less.

[0067] The monomer component includes a siloxane monomer. The monomer component can further include a copolymerizable monomer (e.g., a hydrophobic monomer, a hydrophilic monomer), a crosslinkable monomer, etc., as necessary. The monomer component can be composed of a siloxane monomer and one or more monomers selected from copolymerizable monomers and crosslinkable monomers. The total content of the siloxane monomer, hydrophobic monomer, hydrophilic monomer, and crosslinkable monomer in the monomer component can be, for example, 95% to 100% by weight, or, for example, 97% to 99.9999% by weight.

[0068] Examples of the siloxane monomer include the same siloxane monomers as those mentioned above as being capable of constituting the first polymer.

[0069] In one embodiment, the siloxane monomer includes a long-chain siloxane monomer. A preferred example of the long-chain siloxane monomer is a monomer in which the number of repeating siloxane bonds in one chain is 3 or more, preferably 4 or more, and the total number of siloxane bonds in the molecule is, for example, 100 or less, preferably 80 or less. The effects of the present invention can be preferably achieved by using such a long-chain siloxane monomer in combination with a low-molecular-weight monofunctional monomer that does not contain a nitrogen atom. The long-chain siloxane monomer may be a macromonomer having an average molecular weight (Mw) of more than 1000, for example, 2000 or more.

[0070] The siloxane monomer may be used alone or in combination of two or more. For example, one or more long-chain siloxane monomers (may be macromonomers) may be used in combination with one or more siloxane monomers other than the long-chain siloxane monomers. When two or more siloxane monomers are used in combination, the weighted average molecular weight may be 500 or more.

[0071] The content of the siloxane monomer in the monomer component is, for example, 70% by weight or more, preferably 80% by weight or more, more preferably 85% by weight or more, and even more preferably 90% by weight or more. When the siloxane monomer contains a long-chain siloxane monomer, the content of the long-chain siloxane monomer in the monomer component is, for example, 20% by weight or more, preferably 30% by weight or more, more preferably 40% by weight or more, and may be, for example, 80% by weight or more, 85% by weight or more, or 90% by weight or more. When the siloxane monomer does not contain a siloxane monomer containing a nitrogen atom, the upper limit of the content of the siloxane monomer in the monomer component is, for example, 99% by weight or less, 98% by weight or less, or 95% by weight or less. When the siloxane monomer contains a siloxane monomer containing a nitrogen atom, the upper limit of the content of the siloxane monomer is, for example, 96% by weight or less, 94% by weight or less, or 90% by weight or less. When the content of the siloxane monomer is within the above range, a multilayer film having excellent oxygen permeability can be obtained. Furthermore, when the content of the long-chain siloxane monomer is within the above range, a multilayer film having high oxygen permeability and flexibility can be obtained.

[0072] Examples of the hydrophobic monomer include those mentioned above as examples of the hydrophobic monomer that can constitute the first polymer. The hydrophobic monomer can be used alone or in combination of two or more.

[0073] The content of the hydrophobic monomer in the monomer component is, for example, 90% by weight or less, preferably 0% by weight to 80% by weight, and more preferably 0% by weight to 70% by weight (e.g., 0% by weight to 20% by weight, 0% by weight to 10% by weight, or 0% by weight to 5% by weight). By using the hydrophobic monomer in the above content, it is easy to adjust the properties of the second polymer (e.g., water absorption).

[0074] The hydrophilic monomer may be the same as those mentioned above as the hydrophilic monomers that can constitute the first polymer. The hydrophilic monomers may be used alone or in combination of two or more.

[0075] The content of the hydrophilic monomer in the monomer component is, for example, 80% by weight or less, preferably 0% by weight to 70% by weight, and more preferably 0% by weight to 60% by weight (e.g., 0% by weight to 20% by weight, 0% by weight to 10% by weight, or 0% by weight to 5% by weight). When the content of the hydrophilic monomer is within the above range, a polymer having the desired hydrophilicity can be suitably obtained.

[0076] Examples of the crosslinkable monomer include those mentioned above as crosslinkable monomers that can constitute the first polymer. The crosslinkable monomers can be used alone or in combination of two or more.

[0077] The content of the crosslinkable monomer in the monomer component is, for example, 0 to 25% by weight, preferably 0.1 to 20% by weight, and more preferably 0.5 to 15% by weight. When the content of the crosslinkable monomer is within the above range, the flexibility and mechanical strength of the second polymer can be suitably adjusted.

[0078] The monomer component may further include a functional monomer. Specific examples of the functional monomer and the content ratio thereof are as described for the first polymer.

[0079] In an embodiment of the present invention, when the monomer component constituting the second polymer includes a nitrogen-containing siloxane monomer (e.g., a long-chain siloxane monomer containing a nitrogen atom), the monomer component further includes a monofunctional monomer having a molecular weight of 500 or less and not containing a nitrogen atom. Forming a second polymer layer using a nitrogen-containing siloxane monomer may result in insufficient adhesion to the first polymer layer. However, by combining a low-molecular-weight monofunctional monomer not containing a nitrogen atom, high interlayer adhesion can be ensured. The reason for this effect is unclear, but it is speculated, for example, as follows: Because nitrogen-containing siloxane monomers act as hydrogen bond acceptors, they generally have higher hydrophilicity than non-nitrogen-containing siloxane monomers. Therefore, when a nitrogen-containing siloxane monomer is present in the monomer components constituting the second polymer, if the polarity of the first polymer layer is low, the penetration of the monomer component into the first polymer layer is inhibited due to the difference in polarity. Therefore, adding a monomer with a low molecular weight and low polarity (e.g., non-polar) makes it easier for the monomer component to penetrate into the network of the first polymer. As a result, an IPN (interpenetrating polymer network) structure is suitably formed between the first polymer layer and the second polymer layer, and a multilayer film with excellent interlayer adhesion can be obtained. Note that, when the monomer component constituting the second polymer does not contain a siloxane monomer containing a nitrogen atom, even if the second polymer does not contain a structural unit derived from a low-molecular-weight monofunctional monomer that does not contain a nitrogen atom, a multilayer film with excellent interlayer adhesion between the first polymer layer and the second polymer layer can be obtained. It is presumed that this effect is due to the high affinity between the first polymer layer and the second polymer layer.

[0080] As the monofunctional monomer, any monofunctional monomer having a molecular weight of 500 or less and containing no nitrogen atoms can be used. The molecular weight of the monofunctional monomer may be, for example, 400 or less or 300 or less, or, for example, 80 or more. As such monofunctional monomers, siloxane monomers or hydrophobic monomers can be used because of their excellent affinity with the first polymer layer. Examples of siloxane monomers include the above-mentioned siloxane-containing alkyl(meth)acrylates, siloxane-containing styrene derivatives, and siloxane-containing fumaric acid diesters. Examples of hydrophobic monomers include alkyl(meth)acrylates in which the alkyl group contains 1 to 4 carbon atoms, preferably 1 to 2 carbon atoms. The alkyl group of the alkyl(meth)acrylate may be linear or branched and may contain a halogen (e.g., fluorine). Among these, preferred examples include methyl(meth)acrylate, ethyl(meth)acrylate, and tris(trimethylsiloxy)ethyl(meth)acrylate. The monofunctional monomers can be used alone or in combination of two or more types.

[0081] The content of the monofunctional monomer in the monomer component is, for example, 4 wt% or more, preferably 5 wt% or more, more preferably 10 wt% or more. The content is, for example, 90 wt% or less, preferably 70 wt% or less, more preferably 50 wt% or less, and may be, for example, 30 wt% or less, or, for example, 20 wt% or less. Such a content can favorably improve adhesion to the first polymer layer.

[0082] The second polymer layer may further contain any suitable additive, if necessary. Examples of the additive include additives conventionally used in ophthalmic devices. Examples include cooling agents, thickeners, surfactants, non-polymerizable dyes, and non-polymerizable ultraviolet absorbers.

[0083] The amount of the additive in the second polymer layer 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 second polymer.

[0084] The polymerizable composition and the polymerization method will be described in detail in Section C.

[0085] <Third Polymer Layer> The third polymer layer includes a third polymer containing a structural unit derived from a siloxane monomer. The third polymer layer is substantially composed of the third polymer. Specifically, the content of the third polymer in the third polymer layer in a water-saturated state is typically more than 90 wt %, for example, 95 wt % or more, and may be 97 wt % or more or 98 wt % or more, and for example, 99.95 wt % or less, or may be 99.9 wt % or less.

[0086] When the third polymer layer is disposed in direct contact with at least a portion of the surface of the second polymer layer (e.g., in the configuration shown in FIG. 2 ), the same description as for the first polymer layer can be applied to the third polymer layer. The same description as for the first polymer layer can be applied to the third polymer constituting the third polymer layer, but the type and / or content of the structural units may be different. Specifically, the properties of the third polymer layer in the above configuration are as follows: The water absorption rate of the third polymer layer is typically less than 10 wt %, for example, 3 wt % or less, preferably 2 wt % or less, more preferably 1 wt % or less, and even more preferably 0.5 wt % or less. The lower limit of the water absorption rate is not particularly limited, and the water absorption rate may be, for example, 0.1 wt % or less. The oxygen permeability coefficient of the third polymer layer is, for example, 50 Barrers or more, preferably 100 Barrers or more, and more preferably 150 Barrers or more. The upper limit of the oxygen permeability coefficient is not particularly limited, but may be, for example, 600 Barrers or less. The Rockwell superficial hardness of the third polymer layer is, for example, 20 or more, preferably 30 or more, and more preferably 40 or more. The upper limit of the Rockwell superficial hardness is not particularly limited, but may be, for example, 150 or less. The tensile modulus of the third polymer layer is, for example, 50 MPa or more, preferably 100 MPa or more, and more preferably 200 MPa or more. The upper limit of the tensile modulus is not particularly limited, but may be, for example, 3000 MPa or less, or 2000 MPa or less. The total light transmittance of the third polymer layer is, for example, 80% or more, preferably 90% or more, and more preferably 95% or more. The contact angle of the surface of the third polymer layer opposite to the side in contact with the second polymer layer is, for example, 90° or less, preferably 70° or less, and more preferably 0° to 50°. The surface of the third polymer layer opposite to the side in contact with the second polymer layer may be subjected to a surface modification treatment such as corona treatment or plasma treatment. The dynamic friction coefficient of the surface of the third polymer layer is, for example, 0.1 to 2.0, or, for example, 0.2 to 1.5.

[0087] Alternatively, when the third polymer layer is disposed in direct contact with at least a portion of the surface of the first polymer layer, the same description as for the second polymer layer can be applied to the third polymer layer. The same description as for the second polymer layer can be applied to the third polymer constituting the third polymer layer, but the type and / or content of the structural units may be different (however, the third polymer preferably does not contain structural units derived from nitrogen-containing siloxane monomers, or contains structural units derived from nitrogen-containing siloxane monomers, and further contains 4 wt% or more structural units derived from monofunctional monomers that do not contain nitrogen atoms, with a molecular weight of 500 or less). Specifically, the properties of the third polymer layer in the above configuration are as follows: The water absorption rate of the third polymer layer is, for example, less than 10 wt%, preferably 5 wt% or less, more preferably 3 wt% or less, and even more preferably 2 wt% or less. The lower limit of the water absorption rate is not particularly limited, and the water absorption rate may be, for example, 0.1 wt% or less. The oxygen permeability of the third polymer layer is, for example, 200 Barrer or more, preferably 300 Barrer or more, and more preferably 400 Barrer or more. The upper limit of the oxygen permeability is not particularly limited, but may be, for example, 1000 Barrer or less. The difference between the oxygen permeability of the first polymer layer and the oxygen permeability of the third polymer layer (Dk value of the third polymer layer - Dk value of the first polymer layer) is, for example, 40 Barrer or more, and may be 50 to 1000 Barrer. The tensile modulus of the third polymer layer is, for example, 1000 MPa or less, preferably 500 MPa or less, and more preferably 400 MPa or less. The lower limit of the tensile modulus is not particularly limited, but may be, for example, 0.05 MPa or more, or, for example, 0.1 MPa or more. The total light transmittance of the third polymer layer is, for example, 80% or more, preferably 90% or more, and more preferably 95% or more. The contact angle of the surface of the third polymer layer opposite to the side in contact with the first polymer layer is, for example, 60° to 130°, preferably 70° to 120°, and more preferably 80° to 110°. The dynamic friction coefficient of the surface of the third polymer layer is, for example, 0.2 to 20, or, for example, 1.0 to 15.

[0088] B. Uses of the Multilayer Film The multilayer film according to the embodiment of the present invention can be used as an ophthalmic device such as an ophthalmic lens or an intraocular lens. Examples of the ophthalmic lens include contact lenses including orthokeratology lenses, artificial corneas, and corneal onlays. The ophthalmic lens may be a hybrid lens including a hard contact lens layer and a soft contact lens layer.

[0089] In one embodiment, the multilayer film is a contact lens having a two-layer structure. As shown in Figure 1, the multilayer film (two-layer contact lens) 100A may have a configuration in which the side that contacts the cornea (back side) is a second polymer layer 20 that is a soft contact lens layer, and the opposite side (front side) is a first polymer layer 10 that is a hard contact lens layer. Alternatively, the two-layer contact lens may have a configuration in which the side that contacts the cornea is a first polymer layer that is a hard contact lens layer, and the opposite side is a second polymer layer that is a soft contact lens layer. Preferably, the two-layer contact lens has the configuration shown in Figure 1.

[0090] In another embodiment, the multilayer film is a contact lens having a three-layer structure. As shown in Fig. 2, the multilayer film (contact lens having a three-layer structure) 100B may have a configuration of [third polymer layer (hard contact lens layer) 30 / second polymer layer (soft contact lens layer) 20 / first polymer layer (hard contact lens layer) 10] from the side that contacts the cornea to the opposite side. Alternatively, the contact lens having a three-layer structure may have a configuration of [second polymer layer (soft contact lens layer) / first polymer layer (hard contact lens layer) / third polymer layer (soft contact lens layer)]. Preferably, the contact lens having a three-layer structure has the configuration shown in Fig. 2.

[0091] The ophthalmic device of the present invention may further include a functional element. The functional element may be partially or completely encapsulated (embedded) in the ophthalmic device, or may be held in a surface-engaged state. In one embodiment, the functional element is completely encapsulated in the ophthalmic device. In this case, from the viewpoint of interlayer adhesion, it is preferable that the functional element is not present across the layers, but is encapsulated in one of the layers. It is more preferable that the functional element is encapsulated in the second polymer layer because it has very high oxygen permeability and excellent flexibility.

[0092] 4(a) is a schematic plan view of a multilayer film encapsulating a functional element according to one embodiment of the present invention, (b) is a schematic cross-sectional view taken along line A-A thereof, and FIG. 5(a) is a schematic plan view of a multilayer film encapsulating a functional element according to another embodiment of the present invention, (b) is a schematic cross-sectional view taken along line A-A thereof.

[0093] The multilayer film 100D shown in Fig. 4 is substantially circular in plan view and includes a first polymer layer 10 having a front surface 10a and a back surface 10b, a second polymer layer 20 disposed in direct contact with the back surface 10b of the first polymer layer 10, and a functional element 40 having a circular shape in plan view and contained in the second polymer layer 20. The multilayer film 100E shown in Fig. 5 includes a first polymer layer 10 having a front surface 10a and a back surface 10b, a second polymer layer 20 disposed in direct contact with the back surface 10b of the first polymer layer 10, a third polymer layer 30 disposed in direct contact with the back surface of the second polymer layer 20, and a functional element 40 having a circular shape in plan view and contained in the second polymer layer 20.

[0094] The functional element 40 can be appropriately selected depending on the application. Specific examples of the functional element include a sensor capable of acquiring or monitoring biological information, an optical element capable of displaying an image, and the like.

[0095] C. Method for Producing a Multilayer Film The multilayer film according to an embodiment of the present invention can be produced by any suitable method. For example, the multilayer film can be produced by a production method including polymerizing a polymerizable composition for forming a first polymer layer to obtain a first polymer layer, polymerizing a polymerizable composition for forming a second polymer layer to obtain a second polymer layer, and optionally polymerizing a polymerizable composition for forming a third polymer layer to obtain a third polymer layer in a mold.

[0096] For example, in an embodiment in which the monomer component constituting the second polymer contains a siloxane monomer containing a nitrogen atom, the method for producing a multilayer film preferably includes polymerizing a polymerizable composition for forming a first polymer layer to obtain a first polymer layer, and then placing a polymerizable composition for forming a second polymer layer so as to directly contact at least a portion of the obtained first polymer layer, and polymerizing the composition to obtain a second polymer layer. In the above-mentioned production method, when the multilayer film includes a third polymer layer composed of a third polymer having properties similar to those of the first polymer, the first polymer layer and the third polymer layer can be produced, and then the polymerizable composition for forming the second polymer layer can be placed and polymerized so as to directly contact at least a portion of the first polymer layer. Also, when the multilayer film includes a third polymer having properties similar to those of the second polymer (for example, when the monomer component constituting the third polymer contains a siloxane monomer containing a nitrogen atom), the first polymer layer can be produced, and then the polymerizable composition for forming the second polymer layer and the polymerizable composition for forming the third polymer layer can be placed and polymerized so as to directly contact at least a portion of the first polymer layer, to produce a second polymer layer and a third polymer layer. By preparing a first polymer layer and then disposing and polymerizing a polymerizable composition for forming a second polymer layer so as to be in direct contact with at least a portion of the first polymer layer, a multilayer film having excellent interlayer adhesion between the first polymer layer and the second polymer layer can be suitably obtained.

[0097] The polymerizable compositions for forming the first polymer layer, the second polymer layer, and the third polymer layer may each contain a polymerization initiator and a solvent in addition to the above-mentioned monomer components and additives.

[0098] The polymerization initiator is appropriately selected depending on the polymerization method. Examples of thermal polymerization initiators used for polymerization by heating include 2,2'-azobisisobutyronitrile, 2,2'-azobis(2,4-dimethylvaleronitrile), benzoyl peroxide, t-butyl hydroperoxide, cumene hydroperoxide, lauroyl peroxide, t-butyl peroxyhexanoate, and 3,5,5-trimethylhexanoyl peroxide. These thermal polymerization initiators can be used alone or in combination of two or more.

[0099] The blending ratio of the thermal polymerization initiator in the polymerizable composition is preferably 0.001 to 3% by weight, more preferably 0.01 to 2% by weight, based on all components in the polymerizable composition (excluding the organic solvent).

[0100] Examples of photopolymerization initiators used in polymerization by light irradiation include phosphine oxide-based photopolymerization initiators such as 2,4,6-trimethylbenzoyl-diphenylphosphine oxide (TPO) and bis(2,4,6-trimethylbenzoyl)-phenylphosphine oxide; benzoin-based photopolymerization initiators such as methyl orthobenzoyl benzoate, methyl benzoyl formate, benzoin methyl ether, benzoin ethyl ether, benzoin isopropyl ether, benzoin isobutyl ether, and benzoin-n-butyl ether; 2-hydroxy-2-methyl-1-phenylpropan-1-one (HMPPO), p-isopropyl ether, Examples of suitable photopolymerization initiators include phenone-based photopolymerization initiators such as α-hydroxyisobutylphenone, p-t-butyltrichloroacetophenone, 2,2-dimethoxy-2-phenylacetophenone, α,α-dichloro-4-phenoxyacetophenone, and N,N-tetraethyl-4,4-diaminobenzophenone; 1-hydroxycyclohexyl phenyl ketone; 1-phenyl-1,2-propanedione-2-(o-ethoxycarbonyl)oxime; thioxanthone-based photopolymerization initiators such as 2-chlorothioxanthone and 2-methylthioxanthone; dibenzosubalone; 2-ethylanthraquinone; benzophenone acrylate; benzophenone; and benzil. These photopolymerization initiators can be used alone or in combination of two or more. Furthermore, a photosensitizer may be used together with the photopolymerization initiator.

[0101] The blending ratio of the photopolymerization initiator and the photosensitizer in the polymerizable composition is preferably 0.001% by weight to 2% by weight, more preferably 0.01% by weight to 1% by weight, based on all components in the polymerizable composition (excluding the organic solvent).

[0102] The organic solvent may be a water-soluble organic solvent with high polarity or a water-insoluble organic solvent with low polarity. Examples of water-soluble organic solvents that can be used include alcohols having 1 to 4 carbon atoms, acetone, methyl ethyl ketone, dimethylformamide, dimethyl sulfoxide, acetonitrile, N-methyl-2-pyrrolidone, dimethoxyethane, tetrahydrofuran, and 1,4-dioxane. By using a water-soluble organic solvent, the water-soluble organic solvent can be easily removed from the polymer material by immersion in water.

[0103] Examples of the non-water-soluble organic solvent that can be used include hexane, cyclohexane, heptane, octane, dimethyl ether, diethyl ether, benzene, toluene, xylene, ethyl acetate, propyl acetate, butyl acetate, dichloromethane, chloroform, carbon tetrachloride, and alcohols having 6 or more carbon atoms. When a non-water-soluble organic solvent is added to the polymerizable composition, the kinematic viscosity of the polymerizable composition decreases compared to when a water-soluble organic solvent is used, making the polymerizable composition easier to handle.

[0104] The content of the organic solvent in the polymerizable composition may be, for example, 50% by weight or less, preferably 40 parts by weight or less, and more preferably 30 parts by weight or less. In one embodiment, the content of the organic solvent in the polymerizable composition is, for example, 10% by weight or less, preferably 5% by weight or less, more preferably 3% by weight or less, and may be 0% by weight. When polymerization is performed in an environment with a low organic solvent content or in the absence of an organic solvent, the proportion of the monomer component per unit volume is high and chain transfer to the organic solvent is suppressed, so that a polymer having superior strength or toughness can be obtained compared to polymerization in an environment with a high organic solvent content.

[0105] As the polymerization method, photopolymerization, thermal polymerization, and a combination thereof can be applied.

[0106] When polymerizing a polymerizable composition by photopolymerization, a mold is filled with the polymerizable composition and then irradiated with light (e.g., ultraviolet light). 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.

[0107] 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. The light illuminance and irradiation time are appropriately set depending on the composition of the polymerizable composition, etc. The light irradiation may be performed from only one side of the mold or from both sides. It may also be performed in one step or multiple steps. The light illuminance is preferably 0.1 mW / cm ２ ~300mW / cm ２ The irradiation time is preferably 1 minute or longer. Light of different illuminance may be irradiated in stages. The irradiation temperature is, for example, 10°C to 80°C, preferably 15°C to 60°C.

[0108] When the polymerizable composition is polymerized by thermal polymerization, the polymerizable composition is filled into a mold, and then the mold is gradually heated.

[0109] The heating temperature and heating time when heating the polymerizable composition in the mold are appropriately set depending on the composition of the polymerizable composition, etc. The heating temperature is preferably 50° C. or higher and 150° C. or lower, more preferably 60° C. or higher and 140° C. or lower. The heating time is preferably 10 minutes or higher and 180 minutes or lower, more preferably 20 minutes or higher and 60 minutes or lower.

[0110] FIG. 6 is a schematic diagram illustrating an example of a method for producing a multilayer film. First, a polymerizable composition for forming a first polymer layer is poured into a first mold having a cavity corresponding to the shape of the first polymer layer, and polymerization is carried out to obtain a first polymer layer 10 ( FIG. 6( a)). Next, a second mold having a cavity corresponding to the shape of the laminate of the first polymer layer and the second polymer layer is prepared, and the first polymer layer is placed at a predetermined position within the cavity. Before being placed in the second mold, if necessary, a modification treatment may be carried out on the side surface of the first polymer layer where the second polymer layer will be placed. Next, a polymerizable composition for forming a second polymer layer is poured into the second mold, and polymerization is carried out ( FIG. 6( b)). This results in a multilayer film having a two-layer structure consisting of the first polymer layer 10 and the second polymer layer 20. Furthermore, when a third polymer layer is to be formed, a third mold having a cavity corresponding to the shape of the laminate of the first polymer layer, the second polymer layer, and the third polymer layer is prepared, and the laminate of the first polymer layer and the second polymer layer is placed at a predetermined position within the cavity. Before being placed in the third mold, if necessary, a modification treatment may be carried out on the side surface of the first polymer layer where the third polymer layer will be placed. Next, a polymerizable composition for forming a third polymer layer is poured into the third mold and polymerized (FIG. 6(c)), thereby obtaining a multilayer film having a three-layer structure of the first polymer layer 10, the second polymer layer 20, and the third polymer layer 30.

[0111] FIG. 7 is a schematic diagram illustrating another example of a method for manufacturing a multilayer film. In the manufacturing method shown in FIG. 7, a polymerizable composition for forming a first polymer layer is poured into a first mold having a cavity corresponding to the shape of the first polymer layer and polymerized to obtain a first polymer layer 10. A polymerizable composition for forming a third polymer layer is poured into a fourth mold having a cavity corresponding to the shape of the third polymer layer and polymerized to obtain a third polymer layer 30 ( FIG. 7( a)). Next, a fifth mold having a cavity corresponding to the shape of the laminate of the first polymer layer, the second polymer layer, and the third polymer layer is prepared, and the first polymer layer 10 and the third polymer layer 30 are placed at predetermined positions within the cavity. This forms a cavity 20a corresponding to the shape of the second polymer layer ( FIG. 7( b)). If necessary, before placement in the fifth mold, the side surface of the first polymer layer on which the second polymer layer is to be placed and / or the side surface of the third polymer layer on which the second polymer layer is to be placed may be subjected to a modification treatment. Next, a polymerizable composition for forming a second polymer layer is poured into the cavity 20a and polymerized ( FIG. 7( c)). As a result, a multilayer film having a three-layer structure consisting of the first polymer layer 10, the second polymer layer 20, and the third polymer layer 30 is obtained.

[0112] If necessary, the resulting multilayer film may be immersed in water, an organic solvent, or a mixture thereof to dissolve away residues such as unreacted monomer components, solvent, etc. The residue dissolution treatment may be repeated.

[0113] 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.

[0114] [Components Used] The meanings of the abbreviations of the components used in the examples and comparative examples are as follows: (1) Siloxane Monomer SiSt: tris(trimethylsiloxy)silylstyrene AA-PDMS: one-terminated acrylamide polydimethylsiloxane TRIS: tris(trimethylsiloxy)ethyl methacrylate X-22-164 series: both-terminated methacrylic-modified polydimethylsiloxane (functional group equivalent: 450 g / mol to 3900 g / mol) manufactured by Shin-Etsu Chemical Co., Ltd. MAUS: urethane-containing polydimethylsiloxane diacrylate (n≈30 to 50 in the following structural formula) Urethane-containing siloxane monomer: a macromonomer in which a = 3 to 10, b = 5 to 20, and n = 30 to 50 in the following structural formula (2) Hydrophobic monomers 3FE: 2,2,2-trifluoroethyl methacrylate 6FP: hexafluoroisopropyl methacrylate MMA: methyl methacrylate (3) Hydrophilic monomers MAA: methacrylic acid N-VP: N-vinyl-2-pyrrolidone (4) Crosslinking monomers EDMA: ethylene glycol dimethacrylate (5) Additives (5-1) UV polymerization initiators Irg819: bis(2,4,6-trimethylbenzoyl)phenylphosphine oxide HMPPO: 2-hydroxy-2-methyl-1-phenylpropan-1-one TPO-L: 2,4,6-trimethylbenzoyl-diphenylphosphine oxide (5-2) Non-polymerizable UV absorbers S-703: 2-(5-chloro-2H-benzotriazol-2-yl)-6-(1,1-dimethylethyl)-4-methylphenol

[0115] Example 1A A multilayer film was produced, including a first polymer layer and a second polymer layer disposed in direct contact with the rear surface thereof, as shown in FIG. 1 . Specifically, the process is as follows. A polymerizable composition for forming the first polymer layer was prepared by mixing the components so as to obtain the composition of First Polymer 1-A shown in Table 1. The obtained polymerizable composition was poured into a first mold made of nylon and polypropylene, which had a cavity corresponding to the shape of the first polymer layer. Next, UV light (illuminance of 0.6 mW / cm at 405 nm) was applied to the first mold from the front side at room temperature. ２) for 30 minutes to carry out photopolymerization. This resulted in a first polymer layer (maximum thickness 0.2 mm). Only one side of the first mold was removed, and a nylon mold was attached instead, forming a cavity corresponding to the shape of the second polymer layer, to prepare a second mold. The components were mixed to obtain the composition of second polymer 2-A shown in Table 2, to prepare a polymerizable composition for forming the second polymer layer. The polymerizable composition for forming the second polymer layer was injected into the cavity in the second mold corresponding to the shape of the second polymer layer. At room temperature, UV light (illuminance 0.6 mW / cm at 405 nm) was applied from the back side of the second mold. ２ ) for 60 minutes. This formed a second polymer layer (maximum thickness: 0.3 mm). After polymerization, the contact lens-shaped multilayer film (maximum thickness: 0.5 mm) was removed from the mold.

[0116] Examples 1B to 12E, Comparative Examples 1A to 9E, Reference Examples 1A to 4E Multilayer films were prepared in the same manner as in Example 1A, except that a polymerizable composition for forming a first polymer layer was prepared by mixing the components so as to obtain the compositions of first polymers 1-A to 1-E shown in Table 1, a polymerizable composition for forming a second polymer layer was prepared by mixing the components so as to obtain the compositions of second polymers 2-A to 2-U shown in Table 2 or Table 3, and the first polymer layer and the second polymer layer were polymerized to obtain the combinations shown in Table 4. However, in the case where only HMPPO was used as the initiator, the polymerizable composition for forming a second polymer layer was prepared by mixing the components so as to obtain the compositions of second polymers 2-A to 2-U shown in Table 2 or Table 3, and the first polymer layer and the second polymer layer were polymerized to obtain the combinations shown in Table 4. ２ ) for 30 minutes to perform photopolymerization, and when the initiator was TPO-L, UV light (illuminance 1.2 mW / cm at 405 nm) was used. ２ ) for 30 minutes to carry out photopolymerization.

[0117]

[0118]

[0119]

[0120] Measurement of each physical property of the polymer alone shown in Tables 1 to 3 was carried out using the polymer or its polymerizable composition prepared in the shape of a plate or blank as the measurement sample. The method of preparing the plate or blank and the measurement method are as follows. <Preparation of Plate or Blank> Polymerizable compositions were prepared by mixing the components to obtain the compositions of polymers 1-A to 1-E and 2-A to 2-U shown in Tables 1 to 3. The obtained polymerizable composition was injected into a cavity in the shape of a plate having a thickness of 0.2 mm or 2 mm or a blank having a thickness of 8 mm. At room temperature, UV light (illuminance at 405 nm: approximately 0.6 mW / cm) was applied from one side. ２ ) for 60 minutes. However, when only HMPPO was used as the initiator, UV light (illuminance 6 mW / cm at 365 nm) was used. ２ ) for 30 minutes to perform photopolymerization, and when the initiator was TPO-L, UV light (illuminance 1.2 mW / cm at 405 nm) was used. ２) for 30 minutes to perform photopolymerization. After polymerization, the plate or blank was removed from the mold. The plate was used as is, while the blank was used after cutting and polishing to the desired thickness. <Water Absorption> A 2 mm thick plate was used as the measurement sample. The measurement sample was dried in a 50°C oven for at least 3 hours, and then the weight W1 (g) of the dried measurement sample after being brought to a constant weight was measured. The measurement sample was then immersed in distilled water, left to stand overnight at 25°C, wiped off the surface moisture, and brought to a constant weight again. The weight W2 (g) was measured, and the water absorption was calculated according to the following formula: Water Absorption (%) = (W2 - W1) / W1 x 100 <Rockwell Superficial Hardness> A 4 mm thick blank was used as the measurement sample. Measurement was performed on the measurement sample at 23°C and 50% RH using a Rockwell hardness tester "FR-X3, manufactured by FutureTech Corporation." <Measurement of Oxygen Permeability Coefficient (Dk Value)> A 0.2 mm thick plate was used as the measurement sample. As a reference standard, a similar plate sample was prepared using the material of "Menicon Z" (manufactured by Menicon Co., Ltd.), and the Dk reference value was set to 163. Using a GTG analyzer (manufactured by Rehder Development Company) with the temperature of the measurement sample adjusted to 35°C, oxygen was passed through the measurement sample at a predetermined pressure for a predetermined period of time, and the gas permeability (DP) was measured. This was also carried out for the reference standard. The oxygen permeability coefficient of each measurement sample was calculated according to the following formula: Dk value = L x DP x 1.66 x 10-5 / (C x t x A x (UP x 7.5 - VP - DP)) L: sample thickness (cm) DP: DOWNSTREAM PRESSURE (mmHg) C: (pressure / volume) constant (mmHg / μL) t: set test time (min.) A: area of ​​the test sample (cm ２) UP: Upstream pressure (mmHg) VP: Valve pulse value (mmHg) The Dk value obtained by the above formula was normalized using the following formula: Dk (normalized value) = Dk value (test sample) × Dk standard value (reference standard) / Dk value (reference standard) <Contact angle> A 0.2 mm thick plate subjected to plasma treatment was used as the measurement sample. The contact angle of the plasma-treated surface was measured using a contact angle meter (DropMaster 500, manufactured by Kyowa Interface Science Co., Ltd.) by the sessile drop method. Physiological saline was used as the contact liquid, the droplet volume was 2 μL, and the θ / 2 method was used for analysis. The plasma treatment was performed in an oxygen gas atmosphere at an output of 50 W and a pressure of 100 Pa. <Dynamic friction coefficient> A 0.2 mm thick plate was prepared for each polymerizable composition and used as the measurement sample. The dynamic friction coefficient was measured in air using a nanotribometer (NTR3, manufactured by Anton Paar). The measurement was carried out under the conditions of a φ3 mm sapphire ball as the mating material and a load of 1 mN. <Appearance> A 0.2 mm thick plate was used as the measurement sample. The appearance of each measurement sample was evaluated visually and based on the following evaluation criteria: Transparent: No turbidity observed Cloudy: Turbidity observed <Visible light transmittance> Using each polymer-forming polymerizable composition as the measurement sample, the light transmittance at wavelengths of 210 to 780 nm was measured.

[0121] <Adhesion Evaluation> The multilayer films obtained in the Examples, Comparative Examples, and Reference Examples were cut in the thickness direction, and the adhesion between the first polymer layer and the second polymer layer was evaluated based on the following evaluation criteria. The results are shown in Table 4. ◯ (Good): No lifting or peeling at the interface was observed when the multilayer film was cut. × (Poor): Lifting or peeling at the interface was observed when the multilayer film was cut.

[0122]

[0123] As can be seen from Table 4, in all multilayer films (Examples 1A to E-Examples 9A to E) in which the second polymer layer was composed of a polymer not containing a structural unit derived from a nitrogen-containing siloxane monomer, the adhesion between the first polymer layer and the second polymer layer was good. On the other hand, in the multilayer films in which the second polymer layer was composed of a polymer containing a structural unit derived from a nitrogen-containing siloxane monomer, when the polymer had a molecular weight of 500 or less and contained 4 wt% or more of a structural unit derived from a monofunctional monomer not containing a nitrogen atom (Examples 10A to E-12A to E), the adhesion between the first polymer layer and the second polymer layer was good. However, when the content of such a structural unit derived from a monofunctional monomer was 0 wt% to 3 wt% (Comparative Examples 1A to E-9A to E), the adhesion between the first polymer layer and the second polymer layer was poor. Note that the first polymers A to E showed good adhesion to each other (Reference Examples 1A to E-4A to E).

[0124] A first polymer layer was prepared in the same manner as in the preparation of the above plates, and then a second polymer layer was prepared in direct contact with one side of the first polymer layer to prepare Plate 1-8 (first polymer layer thickness: second polymer layer thickness = 1:3, total thickness 0.4 mm) having a laminated structure of the first polymer layer and the second polymer layer. The combination of polymers constituting the first polymer layer and the second polymer layer, and the Dk value measured for Plate 1-8 are shown in Table 5.

[0125]

[0126] Using the same method as for the above plates, a first polymer layer and a third polymer layer were prepared, and then a second polymer layer was prepared to fill the gap between these layers, resulting in plates 9 and 10 (first polymer layer thickness: second polymer layer thickness: third polymer layer thickness = 1:3:1, total thickness 0.5 mm) having a structure in which the first polymer layer, second polymer layer, and third polymer layer were laminated in this order. The combinations of polymers constituting the first polymer layer to the third polymer layer and the Dk values ​​measured for plates 9 and 10 are shown in Table 6.

[0127]

[0128] The multilayer film of the present invention is suitable for use in ophthalmic devices such as contact lenses, artificial corneas, corneal onlays, and intraocular lenses.

[0129] 10 First polymer layer (first polymer part) 20 Second polymer layer (second polymer part) 30 Third polymer layer 100 Composite film (multilayer film)

Claims

1. A composite membrane comprising: a first polymer portion comprising a first polymer; and a second polymer portion disposed in direct contact with at least a portion of the first polymer portion and comprising a second polymer, wherein the first polymer and the second polymer each comprise structural units derived from siloxane monomers, with the proviso that the second polymer (i) does not comprise structural units derived from siloxane monomers containing nitrogen atoms, or (ii) comprises structural units derived from siloxane monomers containing nitrogen atoms, and in the case of (ii), the second polymer has a molecular weight of 500 or less and comprises 4% by weight or more of structural units derived from monofunctional monomers not containing nitrogen atoms.

2. The composite membrane of claim 1, wherein said first polymer portion is a first polymer layer having a front surface and a back surface, and said second polymer portion is a second polymer layer disposed in direct contact with at least a portion of one surface of said first polymer layer.

3. The composite membrane of claim 2, having a laminate structure in which two or more polymer layers are stacked.

4. The composite membrane of claim 2, wherein said second polymeric layer is disposed in direct contact with at least a portion of said backside surface of said first polymeric layer.

5. The composite membrane of claim 2, further comprising a third polymer layer disposed in direct contact with at least a portion of a surface of said second polymer layer opposite said first polymer layer, said third polymer comprising a third polymer, said third polymer comprising constitutional units derived from a siloxane monomer.

6. The composite membrane of claim 1, having an oxygen permeability of 50 Barrer or greater.

7. The composite film according to claim 1, having a total light transmittance of 80% or more.

8. The composite membrane according to claim 1, wherein each polymer portion has a water absorption rate of 3% by weight or less.

9. The composite membrane of claim 2, wherein at least one of the outermost layers has a Rockwell superficial hardness of 20 or more.

10. The composite film according to claim 1, wherein the first polymer and / or the second polymer contains, as the structural unit derived from the siloxane monomer, a structural unit derived from a long-chain siloxane monomer having a siloxane bond with a repeat number of 3 or more.

11. The composite membrane of claim 10, wherein the total number of siloxane bonds in said long chain siloxane monomer is 100 or less.

12. The composite membrane of claim 10, wherein said second polymer comprises units derived from said long chain siloxane monomers.

13. The composite membrane of claim 1, wherein the first polymer contains 80% by weight or less of constitutional units derived from the siloxane monomer.

14. The composite membrane according to claim 1, wherein the first polymer contains, as the constituent units derived from the siloxane monomer, constituent units derived from a siloxane-containing styrene derivative.

15. The composite membrane of claim 1 which is an ophthalmic device.

16. The composite membrane of claim 1 which is an intraocular lens.

17. The composite film of claim 1 which is a contact lens.

18. The composite film of claim 1 which is an orthokeratology lens.

19. The composite film of claim 1 which is a hybrid lens comprising a hard contact lens portion and a soft contact lens portion.

20. The composite membrane of claim 19, wherein said first polymer portion is said hard contact lens portion.

21. The composite membrane of claim 1 having a functional element embedded therein.

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