JP2009008848A - Contact lens and its manufacturing method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a wearable contact lens having various functions. <P>SOLUTION: A first layer of a biocompatible first lens material is disposed at a position covering a predetermined range of at least one of the front surface and the rear surface of a contact lens, and a functional material is disposed on the center side of the contact lens than the first lens material so as to achieve the function of the contact lens by the functional material. A biocompatible second lens material is placed in a shaping mold so as to be molded with the first lens material and the functional material so as to obtain a safely-wearable contact lens having the function of the functional material. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a contact lens used by being directly attached to a cornea and a method for manufacturing the contact lens.

  Conventionally, a contact lens having a color different from the color of a lens material is known (for example, see Patent Document 1 below). These color contact lenses are used for medical purposes to deal with iris abnormalities such as iris defects and iris excision, and for the purpose of trimming to deal with corneal white spots.

JP-A-2-134612

  In these contact lenses, for example, a colorant is applied to the contact lens surface or molded with a monomer as a lens material. Therefore, in a conventional color contact lens or the like, a colorant or the like is present on the surface of the contact lens. For this reason, a material that is not compatible with a living body such as the cornea could not be used. For example, it has not been possible to impart a dazzling property by applying a material such as a metal that reflects light to the contact lens. Some of the various functional materials that have some optical and electromagnetic functions for the function of the eye are not biocompatible. Could not be realized.

  An object of the present invention is to solve the problems that occur when various functions are imparted to a contact lens, and to provide a contact lens having functionality.

  In order to solve the above-described problems, the contact lens of the present invention employs various configurations described below.

[Application Example 1]
Contact lenses,
A first lens material provided at a position covering a predetermined range of at least one of the front surface and the rear surface of the contact lens, and having biocompatibility;
A functional material disposed closer to the center of the contact lens than the first lens material;
A contact lens comprising a second lens material having biocompatibility and molded by a mold together with the first lens material and the functional material to form the contact lens.

  Since the contact lens having such a structure has a structure in which the functional material is sandwiched between the first lens material and the second lens material having biocompatibility, various functional materials are held in the contact lens. be able to.

  Here, various known materials can be used as the lens material of the contact lens having biocompatibility. MMA (metal methacrylate) of an oxygen non-permeable hard contact lens, SMA (oxygen-permeable hard contact lens) Siloxanyl methacrylate), FMA (fluoromethacrylate), hydrous soft contact lenses HEMA (hydroxyethyl methacrylate), N-VP (N-vinylpyrrolidone), DMAA (dimethylacrylamide), GMA (glycerol methacrylate), non-hydrated It can be applied to silicone rubber, butyl acrylate, dimethylsiloxane, and biocompatible contact lenses such as collagen and amino acid copolymers.

  As the first and second lens materials, so-called polymerizable monomers can be used. As such a polymerizable monomer, a generally used radically polymerizable compound can be considered, for example, a compound containing at least one vinyl group, allyl group, acrylic group, or methacryl group in a molecule, and usually a hard contact lens or Any substance that is used as a soft contact lens material can be used. Specifically, acrylic esters such as alkyl acrylate, siloxanyl acrylate, fluoroalkyl acrylate, hydroxyalkyl acrylate, polyethylene glycol acrylate, vinyl acrylate, styrene derivatives, N-vinyl lactam, vinyl (polyvalent) carboxylate A vinyl compound such as can be considered. More specifically, for example, styrene, acrylic acid, methyl acrylate, ethyl acrylate, n-butyl acrylate, phenyl acrylate, 2-hydroxyethyl acrylate, 2-hydroxypropyl acrylate, methacrylic acid, methyl methacrylate, ethyl methacrylate, n- Butyl methacrylate, 2-ethylhexyl methacrylate, isobornyl methacrylate, benzyl methacrylate, phenyl methacrylate, 2-methacryloyloxyethyl succinic acid, 2-hydroxyethyl methacrylate, 2-hydroxypropyl methacrylate, 2-hydroxybutyl methacrylate, fumaric acid and their Use esters, methacrylonitrile, N, N-dimethylacrylamide, N-vinyl-2-pyrrolidone, etc. Rukoto is possible.

  Further, as a crosslinking agent, ethylene glycol dimethacrylate, diethylene glycol diacrylate, triethylene glycol diacrylate, propylene glycol diacrylate, trimethylolpropane triacrylate, pentaerythritol triacrylate, 1,4-butanediol diacrylate, 1,6- Polyfunctional monomers such as hexanediol diacrylate, glycerin diacrylate, divinylbenzene diallyl phthalate, and diethylene glycol bisallyl carbonate can be used.

  In the above contact lens, at least one of an optical material and an electromagnetic material can be used as the functional material. By selecting these materials, unique optical and electromagnetic characteristics can be imparted to the contact lens.

  Furthermore, in such a contact lens, the optical material can be at least one of a coloring material, a light shielding material, a fluorescent material, a light control material, a reflective material, a high refractive index material, and a polarizing material. Some coloring materials and fluorescent materials do not have biocompatibility. However, since these coloring materials are sandwiched between the first and second lens materials, they can be used as contact lenses. The same applies to other materials.

  Here, as the pigment, it is possible to use iron oxide, titanium dioxide, Phthhalocyanine green, Phthhalocyanine blue, Reactive Red11, Reactive Yellow86, Reactive Black5, or the like alone or appropriately blended. In addition, as a recess for injecting ink, a metal plate that can be easily processed can be used, and a copper plate is particularly suitable. As a pad for collecting ink, a material such as a soft polymer having scientifically stable physical properties with respect to the monomer is suitable, and silicon is particularly suitable. Polyvinyl resin is suitable as a mold for printing ink, but a metal mold or the like can also be used. The contact lens manufactured in this manner does not require any significant addition or modification of the manufacturing process in manufacturing the colored portion. Further, if the colored portion to be formed is made of the same monomer as that of the contact lens, the optical characteristics are the same, and it can be used as a contact lens for correcting refractive errors. If a different monomer is used, the characteristics of the monomer can be used for the colored portion. In such a configuration, since the pigment used for coloring is mixed with the monomer, the colored portion is completely integrated with the contact lens, and even if the component of the pigment alone is deteriorated by tears or the like, it should be used. Can do.

  Further, a drug may be used as the functional material, and the first lens material may have a drug permeability that releases the drug slowly. In this case, since the medicine is gradually diffused through the first lens material, the medicinal effect can be kept long.

  The first lens material having such drug permeability can be formed of a continuous porous body or the like. Moreover, as a chemical | medical agent, it is also possible to use at least one of a fungicide, a nutrient, an allergic inhibitor, and a tear aid. Considering that the number of cases of corneal inflammation caused by cedar pollen allergies in recent years is increasing, it is also preferable to sandwich an allergic inhibitor that deals with such allergies and release them slowly.

  In such a contact lens, the range in which the functional material is disposed can be an optical part including the central part of the contact lens, or a peripheral part (so-called bevel part) of the optical part. The first lens material may be disposed on the front surface or the rear surface of the contact lens.

[Application Example 2]
As a method for manufacturing such a contact lens, the following configuration can be adopted.
Prepare convex and concave types,
Using a transfer pad, a biocompatible first lens material is transferred to a first range that is a predetermined range of one of the convex or concave molding surfaces,
Placing a functional material in a second range narrower than the first range on the transferred first lens material;
A convex or concave mold in which the transfer of the first lens material and the arrangement of the functional material is used and a concave or convex mold corresponding to the convex mold or concave mold, and a second biocompatible material between the two molds. Filled with lens material,
A method for manufacturing a contact lens, wherein after the polymerization of the second lens material, the lens is detached from the mold and post-processed to form a contact lens.

  According to this manufacturing method, it is possible to easily manufacture a contact lens in which a functional material is sandwiched between first and second lens materials having biocompatibility.

[Examples of contact lenses]
In order to further clarify the configuration and operation of the present invention described above, embodiments of the contact lens of the present invention will be described below. FIG. 1 is a central sectional view of a contact lens 10 according to an embodiment of the present invention, and FIG. 2 is a front view thereof. As shown in the figure, the contact lens 10 of the present embodiment is a general contact lens having a circular outer shape, entirely colorless and transparent, and having desired optical characteristics. The innermost circle shown in FIG. 2 is a virtual line indicating the boundary of the optical unit 14 having the optical effect of the contact lens 10.

The contact lens 10 includes a functional material 20 around the optical unit 14. The functional material 20 is actually present on the film layer 12 using the first lens material Hydroxyethyl Mathacrylate (commonly referred to as “hema”, hereinafter referred to as a monomer) and inside the lens. In the first embodiment, carbon having a high light shielding property was used as the functional material 20. For this reason, the contact lens 10 has a high light-shielding region around the optical unit 14.
It is.

[Contact Lens Manufacturing Method]
Next, a method for manufacturing the contact lens 10 will be described. FIG. 3 is a process diagram showing a method for manufacturing the contact lens 10. FIG. 4 is an explanatory diagram schematically showing the state of each mold and lens in the manufacturing process. In both figures, the symbols (A) to (E) indicate the corresponding steps.

  First, as shown in FIG. 4, a convex mold (A1) and a concave mold (B1) for forming a contact lens by a molding method are performed. The convex mold and the concave mold are manufactured by injecting a polyvinyl resin into a mold for producing these molds. As a result, a convex mold (A1) and a concave mold (B1) for molding are obtained. The inner surface of the concave mold is shaped to be the basis of the front curve of the resulting contact lens, while the convex portion of the convex mold forms a contact portion with the cornea of the contact lens 10 to be molded. Therefore, the surface is uniform and smooth (base curve BC). In order to further smooth the surfaces of the concave mold and the convex mold, plasma processing or the like may be performed.

  After the concavo-convex mold is prepared, the manufacturing process shown in FIG. 3 is started, and a process of printing the first layer using the monomer corresponding to the first lens material is performed (step S100). Actually, this is a method of applying a monomer to the inner surface of the concave mold, a method of forming the first layer with a monomer on the inner surface of the concave mold using a silk screen, or a monomer attached to silicon rubber and transferring this to the inner surface of the concave mold. It is done by the method said. As a result, as shown in FIG. 4 (B2), the first layer is formed on the concave inner surface. This state is shown in FIG. The central part of the concave shape is a part corresponding to the optical part 14 of the contact lens 10, and the reference numeral 14 is attached in the figure for convenience of understanding. The first layer made of the first lens material (monomer) is printed in a donut shape surrounding the portion 14 corresponding to the optical part.

  Then, the process which prints the functional material 20 on this 1st layer is performed (process S110). The functional material to be the second layer may be formed by a technique such as coating, silk screen, or transfer, like the monomer that is the first lens material. In this example, the first layer was formed on the concave inner surface by a silk screen, and the second layer was transferred by the following method.

  First, a copper plate for design transfer is prepared and the functional material 20 is prepared. The copper plate is manufactured by engraving a pattern with engraved lines on the surface of the copper plate. The copper plate of the example is engraved in a donut shape as a pattern corresponding to the location of the functional material shown in FIG. As will be described later, ink is applied to the design and remains, and is used for transfer. This is the same method as the dry point in prints. The engraving of the engraved line on the copper plate may be performed manually or by an automated machine tool such as NC.

  On the other hand, the step of preparing the ink is performed as follows. Here, the ink is a real black ink containing carbon. The same monomer and carbon as the hema which is the main material of the contact lens 10 are mixed. Here, black carbon is used, but the ink can be prepared in various colors by appropriately selecting the colorant to be mixed.

  The carbon-containing ink (light-shielding material) thus prepared and prepared is applied to the copper plate, and then the ink on the surface of the copper plate is wiped off. As a result, the ink remains on the copper plate only in the concave portion of the score line. Next, a silicon pad is pressed against the surface of the copper plate. Since the pad made of silicon is rich in elasticity, it is deformed by pressing, and the ink inside the score line is collected on the surface of the pad. Then, next, this silicon pad is pressed against the concave portion of the concave mold (B3). As a result, the ink on the pad surface is transferred to the concave inner surface. This state is shown in FIG. An ink layer containing carbon as a functional material is formed on the monomer 12 of the first layer.

  By the above processing, the first layer 12 made of the first lens material and the second layer 20 of carbon-containing ink which is a functional material are formed. Then, next, the process which fills a concave mold with the monomer (prepared) used as a contact lens is performed (process S120). As a result, as shown in (B4), the concave mold is filled with the lens monomer. In this embodiment, as a material that will eventually become the contact lens 10, Hydroxyethyl Mathacrylate (“hema”) is used. An appropriate amount of this monomer is filled in the concave portion of the concave mold after adjusting the components, the convex mold is fitted, and the monomer is polymerized under predetermined conditions (step S130). As a predetermined condition, in this example, the fitted concave and convex molds were put in an oven and heated at 70 to 80 degrees. By heating, the monomer is polymerized and the contact lens 10 is molded. At this time, the ink containing carbon is also polymerized and integrated with the contact lens.

  In anticipation of the completion of the polymerization, the concavo-convex mold is released (step S140). As a result, the molded contact lens 10 is detached and obtained as shown in (D).

  As a polymerizable monomer for molding a contact lens, 97 parts by weight of 2-hydroxyethyl methacrylate, 2 parts by weight of ethylene glycol dimethacrylate, and 0.3 parts by weight of azobis (2,4-dimethylvaleronitrile) are mixed well. Those subjected to deaeration and nitrogen substitution can also be used. After filling this mixture into the above concave mold and fitting the convex mold, it is put into a hot air circulating thermostat and heated at 40 ° C. for 8 hours and at 80 ° C. for about 5 hours. The molding of the contact lens is completed.

  Although the contact lens 10 thus molded can be used as a product as it is, for example, after detachment, the contact lens 10 is attached to a lathe and a front curve (FC) or a peripheral edge for determining the optical characteristics of the contact lens 10 is used. Cutting such as cutting of the portion and polishing of the edges of the front surface and the peripheral portion may be performed. An appropriate bevel may be provided on the contact lens by polishing the peripheral edge. The contact lens 10 thus obtained is swollen and washed in pure water, and then immersed in physiological saline to absorb a predetermined amount of water (step S150). In this way, the contact lens 10 is completed (E), but in order to handle it as a product, after further inspection, it is generally put in a prestar container, a vial bottle or the like and sterilized.

  According to the manufacturing method as described above, the contact lens 10 in which the functional material 20 is sandwiched can be obtained by a simple procedure. In this contact lens, since the light-shielding region is formed by the functional material 20 containing carbon inside, it is possible to realize a high light-shielding property as compared with a structure simply colored with normal ink. Moreover, since the functional material 20 is sandwiched inside the lens, even if the carbon particles selected as the functional material are as rough as possible, the feeling of wearing is not impaired.

[Examples using other functional materials]
In the above embodiment, carbon is used as the functional material to achieve light shielding, but various functional materials can be used. For example, in order to obtain a light-shielding property, a material using a metal colorant as a functional material can be considered. In a normal contact lens, the metal colorant cannot be used in consideration of contact with the cornea and the like. However, in the case of the contact lens 10 of the present embodiment, the metal colorant is sandwiched inside the contact lens, so that it is used. can do. As a result, a high light shielding property can be imparted to the contact lens.

  Similarly, if a fine powder having polarization characteristics is used as the functional material, polarization characteristics can be imparted to the contact lens. If the contact lens mounting direction is specified, light polarized by reflection from the water surface or road surface can be selectively blocked. Furthermore, if a multilayer thin film having a property of transmitting light of a specific wavelength is formed of a functional material, only light in a specific region of ultraviolet light, infrared light, or visible light can be selectively blocked. It is effective for certain types of eye diseases.

  Alternatively, as the functional material, a material that reacts with light having a specific wavelength can also be used. Here, the light of a specific wavelength is light such as ultraviolet light, infrared light, and visible light, and more preferably light that can be easily handled in daily life. In addition, the reaction is a change such that the functional material that is a colored portion emits light or changes color due to light of a specific wavelength. The colored portion made of such a material can be easily recognized by being irradiated with light of a specific wavelength. For this reason, it is possible to easily recognize that a contact lens is present in the eyeball, and to easily find out by irradiating light of a specific wavelength when the contact lens is lost. In addition, by providing colored parts with different reactions on a plurality of sets of contact lenses, light with a specific wavelength is irradiated to contact lenses that cannot be discriminated whether they are mounted on the left or right in a natural state. Thus, it can also be used as an identification display for distinguishing between left and right mounting. Further, it is possible to use such special ink only for a part of the colored portion and emit the fluorescence only when black light or the like is applied. As such an ink (dye), a material such as florescein is known.

  Next, a contact lens using a reflective material as a functional material will be described. As a functional material, glass or carbon fine powder is used and mixed with a monomer such as hema to prepare. Then, a region including a reflective material is formed in the contact lens according to the manufacturing method. As a result, a contact lens having an anti-glare function can be produced without impairing the wearing feeling of the contact lens. By using such a contact lens, it is possible to prevent a decrease in distance vision that occurs when adapting at night.

  Next, a contact lens using a fragrance or a drug as a functional material will be described. When a fragrance or a medicine is used as the functional material, the first lens material needs to have a property that the fragrance or the medicine sandwiched inside is gradually diffused. Such a lens material can be obtained by preparing water-soluble fine particles in a monomer, polymerizing the monomer, and then melting and removing the fine particles to form a porous body having continuous pores. A fragrance | flavor, a chemical | medical agent, etc. are gradually diffused outside through this porous body. For example, if a fragrance or the like having a stimulating property on the lacrimal gland is used, the lacrimal gland can be stimulated to obtain tears even in the case of dry eye. In addition, the fragrance can bring various effects of the fragrance, such as aromatherapy, to the wearer of the contact lens. In addition, it is possible to obtain a sufficient medicinal effect by sandwiching a drug such as eye disease inside and gradually releasing it.

  As the drug, a drug having a bactericidal effect, a nutrient that requires a nutritional effect, a drug that stabilizes tear quality (for example, lipid, mucin, etc.), vitamins, taurine, aspartic acid, and the like can be used.

  Next, an example using a material having optical characteristics as the functional material will be described. In this example, a high refractive index material was used as the functional material. That is, a material having a different refractive index is adopted as the functional material, and this is sandwiched inside the contact lens. With such a configuration, lens materials having different stiffnesses can be sandwiched, and stable optical characteristics can be realized at the center. Therefore, it is possible to easily manufacture contact lenses for myopia, hyperopia, far-near vision, and astigmatism. Alternatively, it is easy to manufacture contact lenses having different optical characteristics depending on the part.

  Next, a contact lens using a high refractive index glass lens or a high refractive index plastic lens as a functional material will be described. In this example, a micro lens having a high refractive index (a hemisphere or a spherical lens having a radius of about 0.5 to 3 mm) is sandwiched between the contact lenses as a functional material. High refractive index glass lenses are usually not used in consideration of the risk of damage, while high refractive index plastic lenses are not biocompatible (often exhibiting low toxicity) These materials can also be used if they are sandwiched between the first and second lens materials having biocompatibility like the contact lens of the present invention. By sandwiching such a high refractive index micro lens inside, a high refractive index contact lens can be manufactured. For example, it is possible to realize an underwater contact lens that has been almost impossible.

  As mentioned above, although the form in which the present invention is implemented was explained, the present invention is not limited to such an example at all, and it is needless to say that the present invention can be carried out in various modes without departing from the gist of the present invention. is there. For example, in the above embodiment, the first and second layers are formed of the first lens material on the concave inner surface, but the first and second layers may be formed on the convex surface. In addition, the arrangement of functional materials is not limited to the donut shape, and it may be an area of a circle, ellipse, polygon, or any other shape such as a star shape, crescent shape, clover, or heart shape. Is possible.

It is center sectional drawing of the contact lens 10 which is an Example of this invention. It is a front view of the contact lens 10 which is an Example. It is process drawing which shows the manufacturing method of the contact lens 10 in an Example. It is explanatory drawing of the manufacturing process of a contact lens. It is explanatory drawing which shows typically the concave inner surface in a manufacture process (B2). It is explanatory drawing which shows typically the concave inner surface in a manufacturing process (B3).

Explanation of symbols

10 ... contact lens 12 ... first layer (first lens material)
14 ... Optical part 20 ... Functional material (second layer)

Claims (10)

Contact lenses,
A first lens material provided at a position covering a predetermined range of at least one of the front surface and the rear surface of the contact lens, and having biocompatibility;
A functional material disposed closer to the center of the contact lens than the first lens material;
A contact lens comprising a second lens material having biocompatibility and molded by a mold together with the first lens material and the functional material to form the contact lens.   The contact lens according to claim 1, wherein the functional material is at least one of an optical material and an electromagnetic material. The contact lens according to claim 2,
The contact lens is at least one of a coloring material, a light shielding material, a fluorescent material, a light control material, a reflective material, a high refractive index material, and a polarizing material. The contact lens according to claim 1,
The functional material is a drug,
The first lens material is a contact lens having a drug permeability for gradually releasing the drug.   The contact lens according to claim 4, wherein the first lens material having drug permeability is a continuous porous body. The contact lens according to claim 4,
The contact lens includes at least one of a bactericidal agent, a nutrient, an allergic inhibitor, and a tear aid. The contact lens according to claim 1,
The range in which the functional material is disposed is an optical part including a central part of the contact lens, or a contact lens in a peripheral part of the optical part.   The contact lens according to claim 1, wherein the first lens material is disposed on a front surface of the contact lens.   The contact lens according to claim 1, wherein the first lens material is disposed on a rear surface of the contact lens. A method of manufacturing a contact lens,
Prepare convex and concave types,
Using a transfer pad, a biocompatible first lens material is transferred to a first range that is a predetermined range of one of the convex or concave molding surfaces,
Placing a functional material in a second range narrower than the first range on the transferred first lens material;
A convex or concave mold in which the transfer of the first lens material and the arrangement of the functional material is used and a concave or convex mold corresponding to the convex mold or concave mold, and a second biocompatible material between the two molds. Filled with lens material,
A method for manufacturing a contact lens, wherein after the polymerization of the second lens material, the lens is detached from the mold and post-processed to form a contact lens.

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