JP5631655B2 - Contact lens and manufacturing method thereof - Google Patents

Description

The present invention relates to a contact lens having a hydrophilic surface and a manufacturing method thereof.

A hydrous soft contact lens mainly composed of a hydrophilic monomer such as 2-hydroxyethyl methacrylate or vinyl pyrrolidone is excellent in wearing feeling but has low oxygen permeability and is not suitable for long-time wearing. Therefore, a contact lens having a silicon-containing monomer as a main component has been developed as one having improved oxygen permeability.

However, contact lenses mainly composed of silicon-containing monomers have strong surface water repellency, and have problems to be solved for continuous wear, such as water wettability of the lens surface, water retention, and contamination resistance against proteins and lipids. ing. Thus, a contact lens mainly composed of a silicon-containing monomer having a weak surface water repellency has been desired.

As a method for avoiding the strong surface water repellency of a contact lens mainly composed of a silicon-containing monomer, there is a method of making the lens surface hydrophilic by surface treatment. For example, as a method utilizing graft polymerization reaction, a hydrophilic monomer is imparted by graft polymerization of a hydrophilic monomer on the surface of a contact lens substrate that has been subjected to plasma treatment (see Patent Document 1), and the hydrophilic monomer is obtained by dry treatment. A method of surface graft polymerization (see Patent Document 2), a method of performing low-temperature plasma treatment on a hydrogel containing silicon, exposing it to an oxygen atmosphere, and immersing it in a hydrophilic monomer aqueous solution at a temperature of 100 ° C. or higher (Patent Document 3) Reference). Furthermore, a method is disclosed in which a contact lens substrate is subjected to plasma treatment with a non-polymerizable gas after plasma polymerization treatment of methane and wet air (see Patent Document 4).

On the other hand, instead of surface-treating the formed contact lens, a hydrophilic film is applied in advance to a mold for forming the contact lens, and the contact lens is formed using the hydrophilic film to form the contact lens surface. There is a method of making the surface hydrophilic by transferring to the surface. For example, in a contact lens molding mold in which a molding surface is coated with a releasable and hydrophilic polymer, a monomer mixture mainly composed of (meth) acrylic acid ester and a crosslinkable monomer is copolymerized to form a contact lens shape. A method of producing a copolymer and then treating the surface thereof with plasma (see Patent Document 5), irradiating at least a part of the mold surface with excimer light, and then interacting with the polymerization component in the contact lens material A method of uniformly applying a compound that can be fixed on the surface or a solution of the compound and obtaining a contact lens using the applied mold (see Patent Document 6), applying a coating agent to the surface of the mold, and the mold Among them, a method of forming an article by copolymerizing an article-forming material (see Patent Document 7) is disclosed.

JP-A-6-49251 JP-A-8-319329 JP 2003-215509 A JP 2007-70405 A Japanese Patent Laid-Open No. 7-266443 JP 2003-1647 A JP 2005-520703 A

However, both methods have problems.
As for the method of hydrophilizing the lens surface by surface treatment, all of the methods described in Patent Documents 1 to 4 apply a hydrophilic treatment to the formed contact lens, and stress is generated on the contact lens base material. However, deformation and deterioration are expected to occur. In addition, these methods have problems such as requiring an extremely large apparatus and complicated setting of conditions for forming a film.

On the other hand, as for the method of applying a hydrophilic film to the mold, the methods described in Patent Documents 5 to 7 do not require a large-scale apparatus, and the setting conditions are limited. However, among these methods, the methods described in Patent Documents 5 and 6 perform plasma treatment or excimer light irradiation on the surface of the mold in order to improve the affinity between the mold and the film in forming the film on the molding surface. Therefore, the adhesion between the mold and the coating is extremely strong, and it is extremely difficult to release the contact lens from the mold. In addition, even if the mold release can be performed, an excessive physical force is required, and as a result, there is a concern that the optical characteristics may be adversely affected such that the contact lens is deformed or deteriorated. Therefore, in the methods described in Patent Documents 5 and 6, the problem of deformation and deterioration of the contact lens that occurs in the method of making the lens surface hydrophilic by surface treatment is not improved.

On the other hand, according to the method disclosed in Patent Document 7, deformation and deterioration of the contact lens can be avoided. However, the adhesive interface between the contact lens substrate and the hydrophilic polymer layer is not considered, and the hydrophilic polymer having no copolymerizable functional group is partially embedded in the contact lens at the interface. There are only. For this reason, the contact lens obtained by the method described in Patent Document 7 cannot withstand the adhesion between the hydrophilic coating and the contact lens substrate, that is, the durability of the hydrophilic coating.

Therefore, the present inventor has provided the above-mentioned problem, that is, to provide a contact lens having a hydrophilic film with reduced surface deformation and deterioration and higher durability compared to the conventional method, and a method for producing the contact lens. The invention is to solve the problem.

In order to solve the above problems, the present inventor tried to develop a method for producing a contact lens that has a hydrophilic coating that is easy to release from a mold and has a high durability on the surface by an in-mold manufacturing method. . As a result of intensive studies, a viscous solution containing a first hydrophilic polymer having high affinity for the mold is applied to the mold and dried, and then a solution containing a hydrophilic monomer is applied thereon, and then the contact lens group is applied. By injecting a solution containing a material monomer and then carrying out copolymerization and molding of these monomers, the present inventor has obtained a contact lens in which two layers of an outer layer and an inner layer are formed on a contact lens substrate. Successful. The contact lens thus obtained does not require physical treatment such as plasma irradiation when a hydrophilic coating is formed on the surface of the mold in the in-mold manufacturing method. And having a hydrophilic surface excellent in durability. The present invention has been completed based on the above findings.

Therefore, according to the present invention, there is provided a method for producing a contact lens using a plastic contact lens mold;
(1) A step of applying a viscous solution containing the first hydrophilic polymer to the male mold and female mold of the mold and drying to form an outer layer composed of the first hydrophilic polymer;
(2) A step of applying a solution containing a hydrophilic monomer to the male mold and the female mold of the mold in which the outer layer has been formed in the step (1) to form the hydrophilic monomer coating layer as an inner layer;
(3) After injecting the solution containing the contact lens base monomer into the female mold of the mold in which the inner layer is formed by the step (2), the male mold and the female mold of the mold are fitted, and A step of obtaining a contact lens molded article in which two layers of an outer layer and an inner layer are formed on a contact lens substrate by polymerizing the hydrophilic monomer and the contact lens substrate monomer; and (4) the step (3) The method includes the step of obtaining a contact lens by releasing the contact lens molded article obtained by the method from a mold.
Preferably, the solution containing the hydrophilic monomer contains a second hydrophilic polymer.
Preferably, a part of the hydrophilic monomer is the same as a part of the contact lens substrate monomer.

According to another aspect of the present invention, there is provided a contact lens obtained by the method of the present invention.

According to another aspect of the present invention, an outer layer composed of the first hydrophilic polymer;
An inner layer composed of a hydrophilic monomer polymer under the outer layer; and
A contact lens is provided comprising a contact lens substrate monomer polymer under the inner layer.
Preferably, a part of the hydrophilic monomer is the same as a part of the contact lens substrate monomer.

According to the method of the present invention, it is possible to obtain a contact lens imparted with hydrophilicity on the surface by a simplified processing method using an in-mold manufacturing method. Further, when the contact lens is released from the mold, an excessive physical force is not required, so that it is possible to suppress an adverse effect on the optical characteristics of the obtained contact lens. According to the method of the present invention, it is possible to form a hydrophilic film excellent in water retention and stain resistance on a contact lens substrate.

The contact lens of the present invention can reduce the difference in refractive index at the interface between the hydrophilic film and the contact lens substrate, and can be expected to improve the vision correction during wearing. Furthermore, by making the swelling ratio of the hydrophilic coating and the contact lens base material the same, it is possible to suppress distortion during swelling of the contact lens.

Details of the present invention will be described below.
The method of the present invention relates to a method of manufacturing a contact lens using a plastic contact lens mold. The contact lens obtained by the method of the present invention is a contact lens in which two layers of an outer layer and an inner layer are formed on a contact lens substrate.

In the method of the present invention, a viscous solution containing a first hydrophilic polymer is applied to a male mold and a female mold of a plastic contact lens mold, and dried to form the first hydrophilic polymer. A step of forming the outer layer (also referred to as step (1)). The outer layer formed by the step (1) is a hydrophilic layer composed of a hydrophilic polymer. Therefore, the contact lens obtained by the method of the present invention has a hydrophilic layer as an outer layer, so that a hydrophilic film is provided on the lens surface.

The first hydrophilic polymer to be used is not particularly limited as long as it does not lose hydrophilicity even after the outer layer is formed. For example, polyvinylpyrrolidone (PVP), polyvinyl alcohol (PVA), polymethacryloyloxyphosphorylcholine (MPC polymer) , Synthetic polymers such as methylcellulose (MC), hydroxypropylmethylcellulose (HPMC), hydroxymethylcellulose (HEMC), polyquaternium-11, polyquaternium-33, polyquaternium-49, and natural polymers such as hyaluronic acid, chitin, chitosan, sericin These can be used, and these can be used alone or in admixture of two or more. From the viewpoint of extensibility to the mold surface and adhesion after coating, synthetic polymers are preferably used in the method of the present invention, more preferably cellulose derivatives such as methylcellulose, hydroxypropylmethylcellulose, and hydroxymethylcellulose. is there.

The solvent used for dissolving the first hydrophilic polymer is not particularly limited as long as it can dissolve the first hydrophilic polymer, and examples thereof include water and an organic solvent. Alternatively, they can be used as a mixture.

A solution obtained by dissolving the first hydrophilic polymer in a suitable solvent is viscous. Due to the viscosity of the solution, the adhesion of the solution to the mold is improved, and a uniform hydrophilic polymer film can be made of plastic without physical treatment such as plasma irradiation or corona discharge. It can be formed on the surface of the mold. By not performing physical treatment such as plasma irradiation, the adhesiveness between the hydrophilic film and the mold is reduced, and the contact lens and the mold can be easily released. Therefore, if step (1) of the method of the present invention is carried out, it is possible to avoid the distortion of the lens that occurs when the contact lens is released from the mold as in the prior art. The adverse effect on the optical characteristics can be prevented.

In the step (1), the viscosity of the solution applied to the male and female molds of the plastic contact lens mold is preferably 300 to 1500 mPa · s, more preferably 500 to 1000 mPa · s. The method for imparting viscosity to the solution is not particularly limited, and can be carried out, for example, by adjusting the addition amount of the first hydrophilic polymer. For example, the viscosity can be imparted to the solution by adjusting the amount of the first hydrophilic polymer added to 0.1 to 20% by weight, preferably 1 to 10% by weight. However, when the amount of the first hydrophilic polymer added is less than 0.1% by weight, the viscosity of the solution cannot be obtained, so that the adhesion to the mold is deteriorated and the outer layer of the hydrophilic film may not be formed. There is. Moreover, when the addition amount of 1st hydrophilic polymer exceeds 20 weight%, solution viscosity becomes very strong and applicability | paintability is bad and there exists a possibility that the outer layer of a uniform hydrophilic film cannot be formed.

The plastic contact lens mold used in the method of the present invention is not particularly limited as long as it is a mold used for manufacturing a contact lens by an in-mold manufacturing method, and various types used so far. Can be used. The male mold and female mold of the mold are those used in molds in the industry. Usually, the male mold is a convex mold and the female mold is a concave mold.

In the step (1), the method of applying the viscous solution containing the first hydrophilic polymer to the male mold and the female mold of the mold is not particularly limited. For example, a spin coating method, a spray method, Examples include a dipping method and a pad printing method. A method by spin coating or a method by pad printing, which is suitable for controlling the film thickness of the hydrophilic film to be formed is preferable. More preferably, in consideration of the shape of the mold, the male mold can be applied by pad printing, and the female mold can be applied by spin coating. The thickness of the hydrophilic film formed by these methods is preferably 0.01 μm to 10 μm in consideration of the optical characteristics of the obtained contact lens.

A method for drying the liquid part of the solution applied to the male mold and female mold of the molding die can be applied by an ordinary liquid drying method, and is not particularly limited. The liquid part is removed in the temperature range of ° C. In this drying mode, in order to form the outer layer composed of the first hydrophilic polymer in the mold, the boiling point of the solvent that dissolves the first hydrophilic polymer is preferably 100 ° C. or lower.

In the method of the present invention, after step (1), a solution containing a hydrophilic monomer is applied to the male mold and female mold of the mold in which the outer layer is formed in step (1), and the hydrophilic monomer coating layer is formed. A step of forming the inner layer (also referred to as step (2)). The first hydrophilic polymer constituting the outer layer formed in the step (1) serves as an anchor for the hydrophilic monomer coating layer (inner layer) formed in the step (2). On the other hand, there is only adhesion between the outer layer and the mold surface. Therefore, the adhesion between the outer layer and the inner layer is stronger than the adhesion between the outer layer and the mold surface. Due to the difference in adhesiveness, the hydrophilic polymer layer as the outer layer adheres to the contact lens side at the time of releasing, and a contact lens composed of two layers is formed.

The solution containing the hydrophilic monomer can be prepared by mixing a polyfunctional crosslinking component in addition to the polymerizable hydrophilic monomer.

The hydrophilic monomer is not particularly limited, and examples thereof include (meth) acryl group-containing monomers and vinyl group-containing monomers. Specifically, N, N-dimethylacrylamide (DMAA), 2-hydroxyethyl methacrylate (HEMA), (meth) acrylic acid, polyethylene glycol monomethacrylate, glycerol methacrylate, N-vinylpyrrolidone (NVP), N-vinyl- N-methylacetamide, N-vinyl-N-ethylacetamide, N-vinyl-N-ethylformamide, N-vinylformamide and the like can be mentioned, and these can be used alone or in admixture of two or more.

It is preferable that a polyfunctional crosslinking component is added to the solution containing the hydrophilic monomer. Multifunctional cross-linking components include ethylene glycol di (meth) acrylate, diethylene glycol di (meth) acrylate, trierythylene glycol di (meth) acrylate, tetraethylene di (meth) acrylate, polyethylene glycol di (meth) acrylate, Propylene glycol di (meth) acrylate, dipropylene glycol di (meth) acrylate, polypropylene di (meth) acrylate, trimethylolpropane tri (meth) acrylate, pentaerythritol tri (meth) acrylate, pentaerythritol tetra (meth) acrylate, di (Meth) acrylate cross-linking agents such as pentaerythritol hexa (meth) acrylate, allyl methacrylate, diallyl maleate, diallyl fumarate, dia Examples of vinyl crosslinking agents such as rusuccinate, diallyl phthalate, triallyl cyanurate, triallyl isocyanurate, diethylene glycol bisallyl carbonate, triallyl phosphate, triallyl trimellitate, diallyl ether, N, N-diallyl melamine, divinylbenzene These can be used alone or in admixture of two or more.

The total amount of the hydrophilic monomer to be blended is preferably 50 to 99% by weight, more preferably 60 to 95% by weight, based on the total polymerization components. The polyfunctional crosslinking component to be added is preferably 1 to 50% by weight, more preferably 5 to 40% by weight, based on the total polymerization components. When the total amount of hydrophilic monomers is less than 50% and the total amount of polyfunctional crosslinking components is 50% by weight or more, the crosslinking density of the polymer forming the hydrophilic coating increases, and the swelling rate decreases. For this reason, moisture is hardly absorbed in the hydrophilic coating, and there is a tendency that suitable moisture is not applied to the contact lens surface. Moreover, when the total amount of polymerizable hydrophilic monomers is 99% by weight, there is a tendency that a difference occurs between the swelling rate of the hydrophilic coating and the swelling rate of the contact lens substrate. Therefore, it is preferable to adjust the blending amount of the polyfunctional crosslinking component as appropriate in accordance with the desired swelling rate.

By adding the second hydrophilic polymer to the hydrophilic monomer solution, the resulting mixed solution can be adjusted to a viscosity suitable for application to the mold. In addition, when a hydrophilic polymer is present in the inner layer of the hydrophilic film obtained by curing the hydrophilic monomer, a so-called interpenetrating network structure (IPN) is formed, and the water retention and contamination resistance of the contact lens surface are formed. Tend to improve.

The second hydrophilic polymer can be appropriately selected from those listed as those that can be used as the first hydrophilic polymer. All or part of the second hydrophilic polymer and the first hydrophilic polymer may be the same or may be completely different. The second hydrophilic polymer preferably used in the method of the present invention is a synthetic polymer, more preferably polyvinylpyrrolidone, polyquaternium, or methylcellulose, which can be used alone or in admixture of two or more. .

The amount of the second hydrophilic polymer added is preferably 0.1 to 20% by weight, more preferably 1 to 10% by weight. When the amount added is less than 0.1% by weight, the hydrophilic coating formed is not sufficiently water-retentive, so that drying tends to occur. On the other hand, when the content exceeds 20% by weight, when the inner layer of the hydrophilic film is polymerized and cured, the formation of the polymer is hindered, so that a good hydrophilic film tends to be hardly formed. Moreover, since a viscosity increases, there exists a possibility that a uniform film cannot be formed.

The solution containing the hydrophilic monomer preferably has the same viscosity as the viscous solution containing the first hydrophilic polymer used in the step (1). For example, the viscosity is 300 to 1500 mPa · s. Preferably, it is 500 to 1000 mPa · s.

As will be described later, the solution containing a hydrophilic monomer contains a polymerization initiator and the like, and is subjected to a copolymerization reaction in step (3).

An aqueous solution of an ophthalmic drug may be added to a solution containing a hydrophilic monomer. When an ophthalmic drug is used, the ophthalmic drug only needs to contain an amount sufficient to exert a medicinal effect when worn.

Application of the solution containing the hydrophilic monomer to the male mold and the female mold of the mold in which the outer layer is formed in the step (1) is performed by applying the viscous solution containing the first hydrophilic polymer to the mold in the step (1). This can be carried out with reference to the method of applying to male and female molds. A hydrophilic monomer coating layer is formed by coating a solution containing a hydrophilic monomer on a mold. This hydrophilic monomer coating layer becomes an inner layer of a contact lens in which two layers of an outer layer and an inner layer obtained by the method of the present invention are formed on a contact lens substrate by a polymerization reaction of a hydrophilic monomer described later. Therefore, in the present specification, not only a layer composed of a polymer of a hydrophilic monomer but also the hydrophilic monomer coating layer is collectively referred to as an inner layer.

In the method of the present invention, the solution containing the contact lens base monomer is injected into the female mold of the mold in which the inner layer is formed in step (2), and then the male mold and female mold of the mold are fitted, And a step of obtaining a contact lens molded article in which two layers of an outer layer and an inner layer are formed on the contact lens substrate by polymerizing the hydrophilic monomer and the contact lens substrate monomer (also referred to as step (3)). including.

The contact lens obtained by the method of the present invention can take various modes by changing the contact lens substrate monomer used in the step (3). For example, it can take the form of a contact lens having a so-called hydrophobic surface comprising a silicon-containing monomer and / or a polysiloxane macromer, preferably a silicon-containing monomer and / or a polysiloxane macromer and a polymerizable hydrophilic monomer. A so-called silicone hydrogel contact lens may be employed.

When the contact lens obtained by the method of the present invention adopts a so-called hydrophobic surface contact lens obtained by using a silicon-containing monomer as a constituent component, the contact lens substrate monomer used in step (3) contains a silicon-containing monomer. It is possible to include at least one of (meth) acrylate and polysiloxane macromer and to mix them appropriately. It is preferable that the contact lens base monomer is copolymerizable with the hydrophilic monomer used in the step (2).

Examples of silicon-containing (meth) acrylates include trimethylsiloxydimethylsilylmethyl (meth) acrylate, trimethylsiloxydimethylsilylpropyl (meth) acrylate, methylbis (trimethylsiloxy) silylpropyl (meth) acrylate, and tris (trimethylsiloxy) silylpropyl. (Meth) acrylate, mono [methylbis (trimethylsiloxy) silylpropyl (meth) acrylate], tris [methylbis (trimethylsiloxy) silylpropyl (meth) acrylate], methylbis (trimethylsiloxy) silylpropylglyceryl (meth) acrylate, tris ( Trimethylsiloxy) silylpropyl glyceryl (meth) acrylate, mono [methylbis (trimethylsiloxy) siloxy] bis (trimethylsiloxy Silylpropyl glyceryl (meth) acrylate, trimethylsilylethyltetramethyldisiloxypropyl glyceryl (meth) acrylate, trimethylsilylmethyl (meth) acrylate, trimethylsilylpropyl (meth) acrylate, trimethylsilylpropyl glyceryl (meth) acrylate, trimethylsiloxydimethylsilylpropyl glyceryl ( (Meth) acrylate, methylbis (trimethylsiloxy) silylethyltetramethyldisiloxymethyl (meth) acrylate, tetramethyltriisopropylcyclotetrasiloxanylpropyl (meth) acrylate, tetramethyltriisopropylcyclotetrasiloxybis (trimethylsiloxy) silylpropyl (Meth) acrylate, (meth) acryloyloxypro Rutrimethoxysilane, (meth) acryloyloxypropyltriethoxysilane, (meth) acryloyloxypropylmethyldimethoxysilane, (meth) acryloyloxypropylmethyldiethoxysilane, (meth) acryloyloxypropyldimethylmethoxysilane, (meth) acryloyloxy Propyldimethylethoxysilane, (meth) acryloyloxyethyltrimethoxysilane, (meth) acryloyloxyethyltriethoxysilane, (meth) acryloyloxyethylmethyldimethoxysilane, (meth) acryloyloxyethylmethyldiethoxysilane, (meth) acryloyl Oxyethyldimethylmethoxysilane, (meth) acryloyloxyethyldimethylethoxysilane, (meth) acryloyloxymethyl Rutrimethoxysilane, (meth) acryloyloxymethyltriethoxysilane, (meth) acryloyloxymethylmethyldimethoxysilane, (meth) acryloyloxymethylmethyldiethoxysilane, (meth) acryloyloxymethyldimethylmethoxysilane, (meth) acryloyloxy Examples include linear, branched or cyclic alkyl (meth) acrylates such as methyldimethylethoxysilane and (meth) acryloyloxypropyltris (methoxyethoxy) silane.

The polysiloxane macromer is represented by the general formula (1).
General formula (1)
(In the formula, X independently represents a hydrogen atom, a hydroxyl group, a methyl group, CH ₂ ═CH—, or an ethylenically unsaturated polymerizable group of the following general formula (2).
General formula (2)
(In the formula, R ₅ is a hydrogen atom or a methyl group, and n is an integer of 2 to _5. )
However, both Xs are not a hydrogen atom, a hydroxyl group or a methyl group. R ₁ , R ₂ , R ₃ and R ₄ each represent the same or different methyl group or trimethylsiloxy group, and m is an integer of 10 to 150. )

Specific examples of the polysiloxane macromer include α-mono (methacryloxymethyl) polydimethylsiloxane, α, ω-di (methacryloxymethyl) polydimethylsiloxane, α-mono (3-methacryloxypropyl) polydimethylsiloxane, α , Ω-di (3-methacryloxypropyl) polydimethylsiloxane, α-mono (3-methacryloxybutyl) polydimethylsiloxane, α, ω-di (3-methacryloxybutyl) polydimethylsiloxane, α-monovinylpolydimethyl Examples include siloxane and α, ω-divinylpolydimethylsiloxane, and α, ω-di (3-methacryloxypropyl) polydimethylsiloxane is preferable.

It is possible to include one or more polymerizable hydrophilic monomers as a part of the contact lens substrate monomer. The hydrophilic monomer used as the contact lens base monomer may be the same as the whole or a part of the hydrophilic monomer used in the step (2), or may be different from each other.

As the hydrophilic monomer used as the contact lens base monomer, for example, a (meth) acryl group-containing monomer and a vinyl group-containing monomer can be used. Specifically, N, N-dimethylacrylamide (DMAA), 2-hydroxyethyl methacrylate (HEMA), (meth) acrylic acid, polyethylene glycol monomethacrylate, glycerol methacrylate, N-vinylpyrrolidone (NVP), N-vinyl- N-methylacetamide, N-vinyl-N-ethylacetamide, N-vinyl-N-ethylformamide, N-vinylformamide are mentioned. Since a part of the contact lens base monomer is a hydrophilic monomer, it is possible to impart appropriate hydrophilicity and flexibility to the obtained contact lens, so that the wearer can expect to improve wearing feeling.

In a preferred embodiment of the method of the present invention, all or part of the hydrophilic monomer contained in the contact lens substrate monomer is the same as all or part of the hydrophilic monomer used in step (2). When the polymerizable hydrophilic monomer used as the hydrophilic component of the contact lens substrate and the polymerizable hydrophilic monomer for film formation are the same, the copolymerizability between the contact lens substrate and the hydrophilic film is improved, Since it bonds more firmly, it becomes possible to form a hydrophilic film excellent in durability. In addition, since the swelling rate of the contact lens base material and the swelling rate of the hydrophilic film are the same, distortion caused by improper swelling caused by the difference in swelling rate is suppressed. Since the difference in the refractive index at the interface of the coating is also suppressed, the optical characteristics of the obtained contact lens can be improved.

In addition to the silicon-containing (meth) acrylate, polysiloxane macromer, and hydrophilic monomer, the solution containing the contact lens base monomer is appropriately mixed with a monomer that is commonly used in the production of contact lenses and copolymerizable with these. Can be prepared. In preparing the solution, a solvent compatible with the contact lens substrate monomer may be used.

In the step (3), the solution containing the contact lens base monomer is injected into the female die of the mold in which the inner layer has been formed in the step (2) using a commonly used method. As a technical common sense in the industry, since it is difficult to inject a solution containing a contact lens base monomer into a male mold, it is injected into a female mold. Therefore, “injecting into the female mold” does not unnecessarily limit the step (3).

In step (3), the solution containing the contact lens base monomer is injected into the female mold, and then the male and female molds are fitted in a manner normally used, and in step (2) The used hydrophilic monomer and the contact lens substrate monomer are polymerized. The inner layer of the resulting contact lens, that is, the hydrophilic coating portion and the contact lens substrate portion, are obtained by proceeding in parallel with the copolymerization of the hydrophilic monomer and the contact lens substrate monomer used in the step (2). It is possible to improve the adhesion.

The copolymerization reaction is not particularly limited, but for example, a radical polymerization initiator or a photosensitizer can be added to the solution, and the reaction can be carried out under conditions suitable for copolymerization depending on these. As radical polymerization initiators, 2,2′-azobisisobutyronitrile, 1,1′-azobis (cyclohexane-1-carbonitrile), 2,2′-azobis (2,4-dimethylvaleronitrile), 2,2′-azobis (2-methylbutyronitrile), 2,2′-azobis (4-methoxy-2,4-dimethylvaleronitrile), dimethyl 2,2′-azobisbutyrate, 2,2′-azobis Azo polymerization initiators such as (2,4,4-trimethylpentane), diisobutyryl peroxide, di (3,5,5-trimethylhexanoyl) peroxide, dilauroyl peroxide, distearoyl peroxide, di- n-propyl peroxydicarbonate, diisopropyl peroxydicarbonate, di (4-tertiarybutylcyclohexyl) peroxy Sidicarbonate, di (2-ethoxyethyl) peroxydicarbonate, di (2-ethylhexyl) peroxydicarbonate, di (3-methoxybutyl) peroxydicarbonate, cumylperoxyneodecanoate, 1,1, 3,3-tetramethylbutylperoxyneodecanoate, 1-cyclohexyl-1-methylethylperoxyneodecanoate, tertiary hexylperoxyneodecanoate, tertiary butylperoxyneodecanoate, tarcha Lihexyl peroxypivalate, tertiary butyl peroxypivalate, 1,1,3,3-tetramethylbutylperoxy-2-ethylhexanoate, 2,5-dimethyl-2,5-di (2- Hexanoyl) peroxyhexane, tertiary hexylpa Oxy-2-ethylhexanoate, tertiary butyl peroxy-2-ethylhexanoate, tertiary butyl peroxyisobutyrate, tertiary hexyl peroxyisopropyl carbonate, tertiary butyl peroxymaleic acid, tertiary butyl Peroxy-3,5,5-trimethylhexanoate, tertiary butyl peroxylaurate, 2,5-dimethyl-2,5-di (3-methylbenzoylperoxy) hexane, tertiary butyl peroxyisopropyl carbonate , Tertiary butyl peroxy-2-ethylhexyl carbonate, tertiary hexyl peroxybenzoate, 2,5-dimethyl 2,5-di (benzoylperoxy) hexane, tertiary butyl peroxyacetic acid, And organic peroxide-based polymerization initiators such as over-tertiary-butyl peroxybenzoate.

In the method of the present invention, since the hydrophilic monomer used in step (2) and the contact lens base monomer used in step (3) are simultaneously copolymerized, the radical polymerization initiator used in these copolymerization reactions is the same. It is preferable that The addition amount of the radical polymerization initiator is not particularly limited, but is preferably 0.001 to 5.0% by weight, more preferably 0.1 to 1.0% by weight with respect to 100% by weight of the copolymer component. is there.

The method of the present invention includes a step (also referred to as step (4)) of obtaining a contact lens by releasing the contact lens molding obtained in step (3) from the mold. At this time, the contact lens molded product can be released from the mold without applying excessive physical stress. As a result, it is possible to obtain a contact lens that has a highly durable hydrophilic coating on the surface and is extremely small in deformation and deterioration that occur when the mold is released.

In the method of the present invention, the steps (1) to (4) are preferably carried out in order, but the physical and chemical properties of the contact lens obtained by the method of the present invention such as a cleaning step are not adversely affected during the steps. It is possible to carry out as many different steps.

Another aspect of the present invention is a contact lens obtained by the method of the present invention. Such a contact lens comprises an outer layer composed of a first hydrophilic polymer;
An inner layer composed of a hydrophilic monomer polymer under the outer layer; and a contact lens substrate monomer polymer under the inner layer can be adopted.

Hereinafter, preferred embodiments of the present invention will be described, but these embodiments are provided for understanding of the present invention, and the scope of the present invention is not limited to such embodiments.

1. Evaluation Method The following test and evaluation criteria were adopted as a contact lens evaluation method.

[Solution viscosity]
The viscosity was measured using a viscosity measuring device RB-80L (manufactured by Toki Sangyo Co., Ltd.).

[transparency]
The contact lens subjected to the surface treatment was visually evaluated.
○: Completely transparent.
X: Some cloudiness (milky white) is present.

[Water wettability 1]
The contact lens subjected to the surface treatment was immersed in physiological saline at 37 ± 2 ° C. for 24 hours, and then the water wettability of the surface when taken out was visually evaluated.
A: Overall good wettability is shown.
Δ: Water repelling is confirmed partially.
X: Water repelling is confirmed as a whole.

[Contact angle 1]
About the contact lens which completed the evaluation of water wettability 1 as mentioned above, after wiping off the water | moisture content of a surface, contact angle meter CA-D type (made by Kyowa Interface Science Co., Ltd.) was used and contact angle was measured by the droplet method. Measurements were made.

[Water retention 1]
The contact lens subjected to the surface treatment was immersed in physiological saline at 37 ± 2 ° C. for 24 hours, and after the surface moisture was wiped off, the lens weight was measured at room temperature in the atmosphere. Thereafter, the weight of the lens after a certain time elapsed was measured until there was no change in weight. The difference between the lens weight after immersion and the lens weight after a certain period of time is taken as the amount of evaporated water, and the residual moisture content in the lens is calculated from the evaporated water content and water content according to the following equation (1). The value was used as an evaluation of water retention.
Formula (1): Water residual ratio (%) = 100− {evaporated water content (g) / lens water content (g) × 100}
Moreover, from the result, the moisture residual rate at the time of measurement 20 minutes elapsed was evaluated according to the following criteria.
○: Moisture residual rate in the lens is 25% or more.
X: Moisture residual rate in the lens is less than 25%.

[Water wettability 2]
The contact lens subjected to the surface treatment was subjected to 30 scrubbing with fingers using a dedicated cleaning agent (Optifree / Alcon Co., Ltd.), and then evaluated by the same method as for water wettability 1.
A: Overall good wettability is shown.
Δ: Water repelling is confirmed partially.
X: Water repelling is confirmed as a whole.

[Contact angle 2]
About the contact lens which completed the wettability 2 evaluation as described above, after wiping off the water on the surface, the contact angle meter CA-D type (manufactured by Kyowa Interface Science Co., Ltd.) was used, and after washing by the droplet method The contact angle was measured.

[Water retention 2]
After the surface-treated contact lens was scrubbed 30 times with fingers using a dedicated cleaning agent (Optifree / Alcon Co., Ltd.), the same weight measurement as in water retention 1 was performed, and the following formula ( According to 2), the water residual ratio in the lens was calculated and used as an evaluation of water retention.
Formula (2): Water residual ratio (%) = 100− {evaporated water content (g) / lens water content (g) × 100}
Moreover, from the result, the moisture residual rate at the time of measurement 20 minutes elapsed was evaluated according to the following criteria.
○: Moisture residual rate in the lens is 25% or more.
X: Moisture residual rate in the lens is less than 25%.

[durability]
For the contact angle measurement result [contact angle 2] after 30 times of scrubbing with fingers, the difference from [contact angle 1] before scrubbing was used as an evaluation of durability.
○: Difference in contact angle is less than + 10 °
Δ: Contact angle difference is + 10 ° or more and less than 30 °
×: Contact angle difference is 30 ° or more

[Illegal swelling evaluation]
After swelling the surface-treated contact lens, it was cut at the longest part of the diameter to produce a strip having a width of 1.0 mm. Using a projector profile projector (manufactured by Nikon Corporation), the occurrence of deformation (curl (inner winding), warpage (outer winding)) when the strip was viewed from the lateral direction was confirmed. (If it is more than ○, it can be worn.)
◎: No curling or warping ○: Slightly curling or warping △: Slightly large curling or warping ×: Curling or warping occurred in the state of contact lens

[Adjusting the sample lens]
(Sample lens A)
α, ω-di (3-methacryloxypropyl) polydimethylsiloxane (FM-7725 manufactured by Chisso Corporation) 30% by weight, n-butyl vinyl ether (NBVE manufactured by Nippon Carbide Industries Co., Ltd.) 30% by weight, N-vinylpyrrolidone ( NVP) 30 wt% and tridecyl methacrylate (TDMA) 10 wt% were weighed and stirred at room temperature for 30 minutes so that each component was uniform, and then tertiary butyl peroxydecanoate (t -BuND) was added in an amount of 0.5% by weight based on 100% by weight of the monomer mixed solution.

(Sample lens B)
α, ω-di (3-methacryloxypropyl) polydimethylsiloxane (FM-7725 manufactured by Chisso Corporation) 30% by weight, n-butyl vinyl ether (NBVE Nippon Carbide Industries Co., Ltd.) 30% by weight, N, N-dimethyl 30% by weight of acrylamide (DMAA) and 10% by weight of tridecyl methacrylate (TDMA) were weighed and stirred at room temperature for 30 minutes so that each component was uniform, and then tertiary butyl peroxydecanoate as a polymerization initiator. (T-BuND) was added in an amount of 0.5% by weight based on 100% by weight of the monomer mixed solution.

2. Forming hydrophilic film on mold and manufacturing contact lens (1) Example 1
Hydroxypropyl methylcellulose (60SH-50, manufactured by Shin-Etsu Chemical Co., Ltd.) 5.0 (g) was weighed into 100 mL ultrapure water at 80 ° C. and stirred at room temperature for 1 hour. 30 μL of the obtained aqueous solution was dropped on a female mold of a contact lens mold made of polypropylene, and applied by spinning at about 7000 rpm for 20 seconds with a spin coater 1H-DX2 (Mikasa Co., Ltd.). Moreover, it apply | coated to the male die of the contact lens shaping | molding die made from a polypropylene by pad printing hermetic611 (made by Daiichi Mechatech Co., Ltd.). Each was dried at a constant temperature of 50 ° C. for 5 hours to form an outer layer of a hydrophilic film.

Next, polyvinylpyrrolidone (K) was used with respect to 100% by weight of a hydrophilic monomer mixed solution comprising 80% by weight of N-vinylpyrrolidone (NVP Nippon Shokubai Co., Ltd.) and 20% by weight of ethylene glycol dimethacrylate (EDMA Mitsubishi Rayon Co., Ltd.). -90 Gokyo Sangyo Co., Ltd.) was weighed in at 1.0% by weight and stirred for 30 minutes at room temperature so that each component would be uniform, and then tertiary butyl peroxydecanoate (t- 0.5% by weight of BuND) was added, and the mixture was further stirred at room temperature for 30 minutes. 30 μL of the obtained polymerizable hydrophilic monomer solution containing a hydrophilic polymer was dropped onto a female mold of a contact lens molding die made of polypropylene coated with a hydrophilic polymer, and spin coater 1H-DX2 (manufactured by Mikasa Co., Ltd.). ) And spin coated at about 7000 rpm for 20 seconds, and applied to a male mold of a contact lens molding die made of polypropylene by pad printing hermetic 611 (manufactured by Daiichi Mechatech Co., Ltd.). And a contact lens mold coated with a two-layer hydrophilic coating was prepared. Using this mold, the monomer for sample lens A prepared as described above was injected and heated at 70 ° C. for 10 hours in a nitrogen atmosphere to obtain a contact lens.

(2) Examples 2-8
After adjusting the outer layer and inner layer forming solutions of the hydrophilic coating with the blending amounts shown in Table 1 and applying to the male and female dies, the sample lens monomer A or B prepared above was injected. In a nitrogen atmosphere, the mixture was heated at 70 ° C. for 10 hours to obtain a contact lens. The application was performed using spin coating 1H-DX2 (Mikasa Co., Ltd.) or pad printing hermetic 611 (Daiichi Mechatech Co., Ltd.). The spin coating conditions and the film drying conditions after the outer layer application are the same as those shown in Example 1.

The obtained contact lens was immersed in a solution composed of ethanol: pure water = 80: 20 at a constant temperature of 40 ° C. for 3 hours to extract an unreacted portion, and then transferred to a phosphate buffer solution (PBS). The ethanol inside was removed to obtain the desired contact lens. The obtained contact lens was evaluated for transparency, water wettability, contact angle, and water retention by the above methods.

(3) Example 9
The treatment was performed in the same manner as shown in Example 1 except that the hydrophilic polymer mixed solution for forming the inner layer was applied without applying the hydrophilic polymer for forming the outer layer of the hydrophilic coating. Thereafter, the monomer for sample lens A prepared as described above was injected and heated at 70 ° C. for 10 hours in a nitrogen atmosphere to obtain a contact lens. The above-mentioned evaluation was performed about the obtained contact lens.

In Example 9, since the outer layer of the hydrophilic film was not formed, the polymerizable hydrophilic monomer mixed solution as the inner layer could not be applied, and the surface of the obtained contact lens showed water repellency.

(4) Example 10
After forming the outer layer of the hydrophilic coating, the contact lens was manufactured without applying the hydrophilic compound mixed solution as the inner layer, and then treated in the same manner as shown in Example 1, and thereafter The adjusted monomer for sample lens A was injected and heated at 70 ° C. for 10 hours under a nitrogen atmosphere to obtain a contact lens. The above-mentioned evaluation was performed about the obtained contact lens.

In Example 10, the initial values showed good results with respect to transparency and water wettability, but the polymerized hydrophilic monomer mixed solution as the inner layer was not applied, and the adhesion between the hydrophilic film and the contact lens was low. Thus, the contact angle and water retention after the scrub cycle test were low.

(5) Example 11
The treatment was performed in the same manner as shown in Example 1 except that the hydrophilic polymer mixed solution forming the inner layer of the hydrophilic coating was applied without adding the hydrophilic polymer, and then adjusted as described above. The monomer for sample lens A was injected and heated at 70 ° C. for 10 hours under a nitrogen atmosphere to obtain a contact lens. The above-mentioned evaluation was performed about the obtained contact lens.

In Example 11, since no hydrophilic polymer was added to the polymerizable hydrophilic monomer mixed solution as the inner layer, the hydrophilicity of the surface was excellent, but the water retention was low.

The obtained results are shown in Table 1 below. In comparison with Examples 9 to 11, Examples 1 to 8 were rubbed 30 times with fingers in the measurement of transparency, water wettability, contact angle and water retention. The measured values before and after washing were stable and showed good results for durability.
HPMC; Hydroxymethylcellulose (60SH-50 / Shin-Etsu Chemical)
MC: Methylcellulose (SM / Shin-Etsu Chemical)
HEMC: Hydroxyethyl methylcellulose (SEB / Shin-Etsu Chemical)
PVA: Polyvinyl alcohol (JMR10-H / Nippon Vinegar / Povar)
PVP: Polyvinylpyrrolidone (K-90 / Gokyo Industry)
PQ-11; Polyoctanium-11 (HC Polymer 1S (M) / Osaka Organic Chemical Industry)

Claims (5)

A method of manufacturing a contact lens using a plastic contact lens mold;
(1) A step of applying a viscous solution containing the first hydrophilic polymer to the male mold and female mold of the mold and drying to form an outer layer composed of the first hydrophilic polymer;
(2) A solution containing a hydrophilic monomer and a second hydrophilic polymer is applied to the male mold and female mold of the mold in which the outer layer is formed in the step (1), and the hydrophilic monomer coating layer is formed as the inner layer. Forming as a step;
(3) After injecting the solution containing the contact lens base monomer into the female mold of the mold in which the inner layer is formed by the step (2), the male mold and the female mold of the mold are fitted, and By polymerizing the hydrophilic monomer and the contact lens substrate monomer, the outer layer , the polymer of the hydrophilic monomer, and the inner hydrophilic layer formed by the second hydrophilic polymer are contacted. A step of obtaining a contact lens molding formed on a lens substrate; and (4) a step of releasing a contact lens molding obtained in the step (3) from a molding die to obtain a contact lens. Method. The portion of the hydrophilic monomer is identical to a portion of the contact lens base material monomer, the method of claim 1. Obtained by the method according to any one of claims 1-2, contact lenses. An outer layer composed of a first hydrophilic polymer;
An inner layer in which an interpenetrating network structure is formed by the hydrophilic monomer polymer and the second hydrophilic polymer under the outer layer; and
A contact lens comprising a contact lens substrate monomer polymer under the inner layer. The contact lens according to claim 4 , wherein a part of the hydrophilic monomer is the same as a part of the contact lens substrate monomer.