WO2014073568A1

WO2014073568A1 - Colored contact lens with thin inner face-side layer, and method for fabricating same

Info

Publication number: WO2014073568A1
Application number: PCT/JP2013/080014
Authority: WO
Inventors: 岡田　務; 麻衣鈴木
Original assignee: 株式会社メニコンネクト
Priority date: 2012-11-09
Filing date: 2013-11-06
Publication date: 2014-05-15
Also published as: JPWO2014073568A1

Abstract

Provided is a colored contact lens having a center thickness of 80-200µm, comprising: a first polymer layer having an interior surface of the contact lens with a center thickness of 5-40µm; a second polymer layer having an exterior surface of the contact lens; and a light-blocking pattern between the two polymer layers. Also provided is a colored contact lens having a center thickness of 50µm or more and less than 80µm, comprising: a first polymer layer having an interior surface of the contact lens with a lower bound center thickness of 5µm and an upper bound center thickness of 35% of the center thickness of the contact lens; a second polymer layer having an exterior surface of the contact lens; and a light-blocking pattern between the two polymer layers.

Description

Colored contact lens with thin inner surface layer and method for producing the same

The present invention relates to a contact lens having a two-layer structure in the thickness direction and a colored portion between the two layers, and a method for producing a laminated colored contact lens by sequentially polymerizing each layer in a mold. Is.

A method of polymerizing a contact lens (hereinafter sometimes simply referred to as “lens”) in a mold (hereinafter simply referred to as “molding method”) generally includes a female mold that forms the front side of the lens and a rear surface side. A lens is obtained by filling a polymerizable monomer between the male mold and forming a lens and irradiating with heat or ultraviolet rays. Since the process is simple and short in this way, it has been widely adopted as a manufacturing method for disposable lenses, which has become the mainstream in recent years. Since the main problems such as polymerization shrinkage of the lens forming material in the lens mold manufacturing method and burrs and chips at the edge of the lens have been solved one after another, the lens can be provided at low cost by the mold manufacturing method. Nowadays, it has been required to increase the added value of the lens by adding new functions by utilizing the characteristics of the mold manufacturing method.

An example of increasing the added value of a lens is a colored lens that objectively changes the color or texture of the pupil. These lenses are also called irised lenses, but the manufacturing method for these lenses is to coat the colored monomer component on the part that forms the iris part of the lens molding die surface, form a film, and then fill and polymerize the lens monomer component. A method in which a colored lens is formed when removed from the mold (Patent Document 1), a colored liquid film is deposited in the mold, and the liquid lens-forming mixture is applied to the mold while maintaining the position of the colored film. There is a method (Patent Document 2) of filling and forming a molded contact lens in which the film surface and the lens body are integrated. In the lenses obtained by these manufacturing methods, the colored portion does not appear to protrude on the lens surface, and the wearer's eyelid or the like does not cause a sense of incongruity directly. However, in some rare cases, a colored portion may appear on the lens surface. Depending on the bonding strength between the lens body material and the colored portion, the colored portion may peel off, resulting in irritation to the wearer or the colored portion. Sometimes felt the difference in hardness between the surrounding area and the surrounding area. In addition, there is a risk that dirt may adhere to the colored portions appearing on the lens surface.

Therefore, a so-called sandwich sandwiching the colored portion inside the lens, that is, a sandwich type lens has been proposed. For example, after a colored part is provided between the hydrogel layers of the lens, the hydrogel is joined by polymerization (Patent Document 3), and an iris shielding means is provided between the first lens part and the second lens part. A method of disposing and joining the first lens portion and the second lens portion (Patent Document 4), a transfer material provided with a transfer layer for forming a colored portion is placed in a female mold, A method of injecting a contact lens material between male molds forming a polymer (Patent Document 5), forming a first lens material in a concave mold, that is, a female mold, and forming a functional material serving as a colorant thereon After printing, the lens material is filled, and a convex surface that is paired with the female mold, that is, a method of polymerizing by fitting the male mold (Patent Document 6) or a colored layer having a predetermined thickness by a mold manufacturing method. There are at least two lenses comprising a transparent layer having a predetermined thickness (Patent Document 7) or the like is arranged in. A colored lens in which a colored portion is coated with a coat layer has been proposed (Patent Document 8).

However, the method of Reference 3 does not use a mold, and the method of Reference 4 is supposed to perform processing by a standard method after a manufacturing method using a mold. The manufacturing cost is high and complicated. The method of Document 5 does not make the lens into a two-layer structure, but uses a transfer layer for coloring, etc., so that the handling of the transfer layer causes a problem in coloring quality and the manufacturing cost is high. There is a risk. In the method of Document 6, a functional material such as a light shielding material is applied to a concave mold and transferred to a lens, so that it has a two-layer structure and a colored portion between the two layers. It is not suitable for the production of colored contact lenses having Furthermore, the method of Document 7 can provide a lens having a three-dimensional appearance by using alternately arranged transparent layers and colored layers, and although the thickness of each layer is also described, There is no mention of any issues. Reference 8 describes a lens comprising a lens-forming polymer, a front lens surface, a rear lens surface, a colorant applied to the exterior of the front or rear lens surface, and a colorant coated with a coat layer. In order to manufacture the lens of Document 8, a process of forming a coat layer is necessary, and the lens of Document 8 may cause eye irritation due to dropping off of the colorant containing the coat layer.

Here, a description will be given of the case where the colored contact lens has a two-layer structure and the colored portion is a sandwich type. When viewed from the position of the colored portion of the sandwich-type contact lens, a polymer provided with the inner surface of the contact lens (that is, the surface in contact with the eyeball when the contact lens is worn on the eyeball, hereinafter simply referred to as “inner surface”). There are two layers: a layer and a polymer layer provided with an outer surface side surface of the contact lens (that is, a surface contacting the outside when the contact lens is worn on the eyeball, hereinafter simply referred to as “outer surface”). Here, in the sandwich type contact lens, there are a lens having a thinner polymer layer having an outer surface and a lens having a thicker one than a polymer layer having an inner surface. For example, colored lenses in which the thickness of the polymer layer having the inner surface of the contact lens is thinner than the thickness of the polymer layer having the outer surface of the contact lens are described in

Documents

4 and 7 among the documents. However, as described above, these documents do not recognize the problems in the present invention described below, and naturally do not describe the problems to be solved. Therefore, there is no means for solving the problems and problems of the present invention. It can be said that it was still a solution. That is, the object of the present invention is to compare the thickness of the polymer layer having the inner surface with the thickness of the polymer layer having the outer surface in the two-layer colored contact lens by the mold manufacturing method, and the former is not thinner than the latter. Is caused by the dry state of the colored contact lens that is inevitably generated when the colored contact lens is worn, and the shape of the colored contact lens changes, thereby impairing visual stability and reducing the feeling of wearing. The problem is that the colored contact lens is easily displaced from the eyes, the fitting is changed, and the dryness is increased. The inventors of the present invention also found that the stress remaining on the colored contact lens by the mold manufacturing method that was relaxed in the hydrated, equilibrium swollen colored contact lens is not relaxed in the colored contact lens in the dry state. It was found that the lens shape is changed so as to cause a change. Furthermore, when the residual stress is strong, the inventors have found that the shape of the hydrated and swollen colored contact lens is remarkably changed, leading to a decrease in the yield rate and cost increase. The possibility of the shape change of the colored contact lens is possessed by the contact lens even if the contact lens is not in a dry state. For example, the contact lens may become apparent when the contact lens that is not in a dry state is cut. In other words, when the contact lens is cut, the contact lens that does not have the possibility of shape change retains the original uneven shape of the contact lens, but the contact lens that may change shape has the original uneven state. The shape may be more distorted.
Therefore, the present invention has solved the above-mentioned problems by defining the thickness of a polymer layer having an inner surface to a predetermined thickness, and has completed the invention.

Japanese Patent Laid-Open No. 2-134612 JP-A-3-15020 Japanese Patent Publication No.54-2856 Japanese Patent Laid-Open No. 2-181723 JP-A-6-258604 JP 2009-8848 A Special table 2010-529505 gazette JP 2005-531810 A

A first problem of the present invention is that a sandwich-type colored contact lens having a two-layer structure has a stable shape even when worn for a long time by defining the thickness of a polymer layer having an inner surface to be a predetermined thickness. It is to provide a colored contact lens that can be maintained. More specifically, the shape of the colored contact lens changes due to the dry state of the colored contact lens that is inevitably generated during wearing, which impairs visual stability and makes the colored contact lens easily displaced. Thus, the problem that the feeling of wearing becomes worse, the fitting and appearance change, and the feeling of dryness becomes stronger is solved by maintaining the shape retaining property of the colored contact lens. And the 2nd subject of this invention is to prevent the fall of the yield rate of the colored contact lens which has a 2 layer structure by a mold manufacturing method, and to improve productivity.

A first aspect of the present invention is a colored contact lens having a center thickness of 80 μm or more and 200 μm or less, the first polymer layer having an inner surface of the contact lens having a center thickness of 5 μm or more and 40 μm or less, and an outer surface of the contact lens A colored contact lens comprising: a second polymer layer comprising: a light shielding material pattern portion between the two polymer layers.
A second aspect of the present invention is a colored contact lens having a center thickness of 50 μm or more and less than 80 μm, wherein the lower limit of the center thickness is 5 μm and the upper limit is 35% with respect to the center thickness of the contact lens. The colored contact comprising: a first polymer layer having an inner surface; a second polymer layer having an outer surface of a contact lens; and a light shielding pattern portion between the two polymer layers. It is a lens.
According to a third aspect of the present invention, a contact lens is formed in a space formed by matching a male mold having a convex molding surface and a female mold having a concave molding surface. 1 lens forming material is filled and polymerized to form a first polymer, the male mold and the female mold are opened to fix the first polymer to the male mold, and the first mold fixed to the male mold A light shielding material is applied to the exposed surface of the polymer, and a second die of the contact lens is formed in a space formed by matching the female die paired with the male die to which the first polymer is fixed. 1st or 2nd aspect which fills the lens forming material of this, polymerizes, forms a 2nd polymer, and impregnates the physiological solution in the 2 layer polymer obtained by opening a male type | mold and a female type | mold. This is a method for producing a colored contact lens.
According to a fourth aspect of the present invention, there is provided a contact lens in a space formed by matching a male mold having a convex molding surface and a female mold having a concave molding surface. The lens forming material 2 is filled and polymerized to form a second polymer, the male mold and the female mold are opened, the second polymer is fixed to the female mold, and the second mold is fixed to the female mold. A light shielding material is applied to the exposed surface of the polymer, and a first die of the contact lens is formed in a space formed by matching the male die paired with the female die to which the second polymer is fixed. 1st or 2nd aspect which fills the lens formation material of this, polymerizes, forms a 1st polymer, and impregnates the physiological solution in the 2 layer polymer obtained by opening a male type | mold and a female type | mold This is a method for producing a colored contact lens.

In this specification, the inner surface of the contact lens, the so-called BC-side inner surface, refers to the surface that contacts the eyeball when the contact lens is worn, and the outer surface of the contact lens, that is, the FC-side outer surface is the opposite side of the BC-side inner surface. The surface on the side that touches the outside world. In the present specification, a polymer constituting the inner surface layer is referred to as a “first polymer”, and a polymer constituting the outer surface layer is referred to as a “second polymer”. The colored contact lens of the present invention has a first polymer layer on the inner surface side and a second polymer layer on the outer surface side, and a pattern of light shielding material is provided between these two polymer layers. Has a part.

The first and second polymers constituting the colored contact lens of the present invention are generally provided as a soft lens after being impregnated with a physiological solution such as physiological saline and brought into an equilibrium swelling state. As used herein, the term “polymer layer” refers to a layer-shaped polymer that has been hydrated and brought into an equilibrium swollen state as a result of impregnating a polymer constituting a colored contact lens with a physiological solution. . Further, in this specification, the “center thickness of the contact lens” means the thickness of the center portion of the contact lens when the polymer is impregnated with a physiological solution and hydrated to be in an equilibrium swollen state. First, the range of the center thickness of the first polymer layer provided with the inner surface of the colored contact lens will be described. The center thickness of the colored contact lens is adjusted by the refractive index of the contact lens material, the required lens power, and the like, and is generally 50 μm or more and 200 μm or less. Therefore, the center thickness of the colored contact lens in the present invention is also preferably 50 μm or more and 200 μm or less, more preferably 80 μm or more and 200 μm or less, further preferably 80 μm or more and 140 μm or less, and most preferably 80 μm or more and 120 μm or less. The lower limit of the center thickness of the first polymer layer provided with the inner surface of the colored contact lens is preferably 5 μm, more preferably 10 μm. When the thickness of the first polymer layer that is in contact with the male mold at the time of manufacturing the colored contact lens is less than 5 μm, the thinner the first polymer, the more stable quality is maintained in the formation of the first polymer. Difficult to do. Further, if the center thickness of the first polymer layer is too thin, the distance between the cornea and the colored material is too small, which may cause an adverse effect on the cornea. On the other hand, the upper limit of the center thickness of the first polymer layer having the inner surface is classified according to the center thickness of the colored contact lens. That is, when the center thickness of the colored contact lens is 80 μm or more and 200 μm or less, the upper limit is preferably 40 μm, more preferably 35 μm, still more preferably 30 μm. This is because if the center thickness of the first polymer layer having the inner surface of the colored contact lens exceeds 40 μm, the problem of the present invention cannot be solved.
When the center thickness of the colored contact lens is 50 μm or more and less than 80 μm, the upper limit is 35% as a ratio of the center thickness of the first polymer layer including the inner surface of the colored contact lens to the center thickness of the colored contact lens. Preferably, it is 32.5%, more preferably 30%. This is because if the ratio exceeds 35%, the problem of the present invention cannot be solved. As a specific example, when the center thickness of the colored contact lens is 60 μm, the preferable upper limit thickness is 60 μm × 0.35 = 21 μm, and the more preferable upper limit thickness is 60 μm × 0.325 = 19.5 μm. The more preferable upper limit thickness is 60 μm × 0.30 = 18 μm. In summary, when the center thickness of the colored contact lens is 80 μm or more and 200 μm or less, the preferred range of the center thickness of the first polymer layer provided with the inner surface of the colored contact lens is preferably 5 μm or more and 40 μm or less. On the other hand, when the center thickness of the colored contact lens is 50 μm or more and less than 80 μm, the lower limit of the center thickness range of the first polymer layer provided with the inner surface of the colored contact lens is preferably 5 μm, and the upper limit of the range is that of the lens. Depending on the center thickness, the ratio of the colored contact lens to the center thickness is 35%.

A light shield is a substance that functions to color a contact lens by blocking a part of light that reaches the eyes from the outside. After the light shielding material is applied to the exposed surface of the first polymer by printing or the like, the second polymer is formed on the exposed surface of the first polymer, or the light shielding material is the second polymer. The light shielding material can be sandwiched in the contact lens by forming the first polymer on the exposed surface of the second polymer after being applied to the exposed surface of the second polymer by printing or the like.

Here, the pattern of the light shielding object is a pattern of the light shielding object. As described above, the pattern is formed by printing, or the colored area surrounding the transparent central visual area is a continuous sea part. A sea-island structure composed of the transparent portion and the discontinuous colored opaque portion of the island portion can be formed. The thickness of the light shield is preferably 5 μm or more and 15 μm or less, and more preferably 8 μm or more and 12 μm or less. If the thickness of the light shielding material is less than 5 μm, the light shielding is insufficient, and if it exceeds 15 μm, the two polymer layers sandwiching the light shielding material may peel off, which may cause a problem in the shape retention of the contact lens. It is. The ratio of the thickness of the light shielding layer to the center thickness of the first polymer layer provided with the inner surface of the colored contact lens is such that when the center thickness of the colored contact lens is 80 μm or more and 200 μm or less, the inner surface of the colored contact lens is Since the lower limit of the center thickness of the first polymer layer provided is 5 μm and the upper limit of the thickness of the light shielding layer is 15 μm, the maximum is 300%, and the center of the first polymer layer provided with the inner surface of the colored contact lens Since the upper limit of the thickness is 40 μm and the lower limit of the thickness of the light shielding layer is 5 μm, the minimum is 12.5%. On the other hand, when the center thickness of the colored contact lens is 50 μm or more and less than 80 μm, the lower limit of the center thickness of the first polymer layer including the inner surface of the colored contact lens is 5 μm, and the upper limit of the thickness of the light shielding layer is 15 μm. Therefore, the upper limit of the center thickness of the first polymer layer provided with the inner surface of the colored contact lens is 28 μm, and the lower limit of the thickness of the light shielding layer is 5 μm. Therefore, the minimum is 17.9%. Become.

Next, a method for manufacturing a colored contact lens according to the third and fourth aspects of the present invention will be described. The “pair” in the third and fourth embodiments means that a lens forming material is added to a female mold, matched with the male mold, polymerized with the lens forming material, and opened to form both molds. This means a combination of a female mold and a male mold designed and manufactured so that Here, the lens forming material is a flowable polymerizable material that forms a lens after polymerization. The lens forming material includes a first lens forming material and a second lens forming material. In the colored contact lens of the present invention, the lens forming material that forms the first polymer layer having the inner surface is “first”. The lens forming material that forms the second polymer layer having the outer surface of the contact lens is the “second lens forming material”. The first lens forming material or the second lens forming material is polymerized between the matched male mold and female mold to form a first polymer or a second polymer, respectively. Next, the female mold and the male mold are opened in the next step. At this time, the previously formed polymer is fixed to either the male mold or the female mold, and in the subsequent step, a light shielding material is applied to the exposed surface of the fixed polymer. In the third aspect, the first polymer is fixed to the male mold, and the light shield is applied to the exposed surface of the first polymer fixed to the male mold. The mold that makes a pair with the male mold to which is fixed is a female mold. The pair of female molds to be used subsequently may be new female molds that are not used, but those that have already been used in consideration of cost reduction may be reused. On the other hand, in the fourth embodiment, the second polymer is fixed to the female mold, and the light shield is applied to the exposed surface of the second polymer fixed to the female mold. A mold that makes a pair with a female mold to which an object is fixed becomes a male mold. The pair of male molds to be used subsequently may be new male molds that are not used, but those that have already been used in consideration of cost reduction may be reused.

In the third aspect of the present invention, a first polymer is first formed, a light shielding pattern is formed, and then a second polymer is formed. First, the first polymer is fixed to the male mold, and a light shielding material is formed on the convex portion of the first polymer, and the second polymer is joined along the concave surface. Here, the light shielding material can be applied twice or more, and thus different patterns can be applied to increase the added value. The first polymer and the second polymer may be a transparent layer containing no dye or the like, or a colored transparent layer containing a dye or the like. This is because adding a dye or the like to the transparent layer may increase the added value in combination with the pattern of the light shielding object.
Moreover, in the 4th aspect of this invention, a 2nd polymer is formed first, the pattern of a light-shielding material is formed, and then a 1st polymer is formed. The second polymer is fixed to the female mold, and a light shielding material is formed on the concave surface portion of the second polymer, and the second polymer is joined so that the convex surface of the first polymer follows. Similar to the third aspect, the light shielding object can be applied two or more times, so that different patterns can be applied and the added value can be increased. The first polymer and the second polymer may be a transparent layer containing no dye or the like, or a colored transparent layer containing a dye or the like.

In the third aspect, since the first polymer is fixed to the male molding surface, the center thickness of the first polymer is the center of the lens on the male convex molding surface when the molds are matched. Defined by the distance between the point and the lens center point on the female concave mold surface.
On the other hand, in the fourth aspect, the center thickness of the first polymer is determined by the center point of the male lens where the polymer is not fixed and the lens center of the exposed surface of the second polymer fixed to the female die. It will be determined by the distance of the points.
The colored contact lens of the present invention can be obtained by immersing the two-layered polymer obtained in the third and fourth aspects in a physiological solution such as physiological saline to bring it into an equilibrium swelling state. Here, the center thickness of the colored contact lens is finally determined by the center thickness of the two-layered polymer molded and bonded in the mold, swelling during hydration, shrinkage during polymerization, and the like. As described above, in this specification, the “center thickness” of the colored contact lens is a thickness after impregnating a physiological solution into a bilayer polymer to obtain an equilibrium swollen state. The thickness obtained by dividing the thickness of each subsequent polymer layer by the linear expansion coefficient (LSR) of each polymer is the thickness of each polymer before the impregnation treatment, that is, at the time of production.

The colored contact lens manufactured by the above-described manufacturing method can add a new function as a colored contact lens having a two-layer structure in the colored thickness direction even if a lens material similar to the conventional lens material is used. In addition, by superimposing the layer structure, it is possible to provide a novel colored contact lens material as a whole by drawing out excellent points of each material and compensating for the defects. In addition, the rate of non-defective products at the time of lens production will be improved to reduce costs.

By making the thickness of the first polymer layer provided with the inner surface of the colored contact lens a predetermined thickness, the deformation of the colored contact lens due to the unavoidable occurrence of water evaporation of the colored contact lens is suppressed and stable for a long period of time. Maintain shape.

Furthermore, since the colored contact lens of the present invention has a two-layer structure, by using an appropriate material for each layer, a problem that cannot be solved by a single material is solved as a whole by combining a plurality of materials. Simple colored contact lenses.

FIG. 1 is a diagram for explaining a method for producing a colored contact lens having a two-layer structure. FIG. 2 is a diagram for explaining another method for producing a colored contact lens having a two-layer structure. FIG. 3 is a diagram showing a cross section in the diameter direction of a colored contact lens having a two-layer structure. FIG. 4 is a photograph showing the contact lens shape in Example 4 and Comparative Example 4, wherein (a), (b), and (c) are 0 minutes and 20 minutes after the start of drying of the colored contact lens in Example 4, The lens shape after 45 minutes is shown, and (d), (e), and (f) are photographs showing the contact lens shape after 0 minutes, 20 minutes, and 45 minutes from the start of drying of the colored contact lens in Comparative Example 4. is there.

The present invention relates to a colored contact lens having a two-layer structure in the thickness direction in which the center thickness of the first polymer layer provided with the inner surface of the colored contact lens is a predetermined thickness, and a method for manufacturing the same. Means that when the center thickness of the colored contact lens is not less than 80 μm and not more than 200 μm, the center thickness of the first polymer layer having the inner surface is not less than 5 μm and not more than 40 μm, and the center thickness of the colored contact lens is not less than 50 μm and less than 80 μm In some cases, the lower limit of the center thickness of the first polymer layer having the inner surface is 5 μm, and the upper limit is 35% as the ratio of the center thickness of the first polymer layer having the inner surface to the center thickness of the colored contact lens. Means that. Hereinafter, it demonstrates concretely, referring drawings.

In the present invention, the colored contact lens is manufactured through at least two polymerization steps so as to have a two-layer structure. FIG. 1 illustrates a process of manufacturing a colored contact lens having a two-layer structure. First, a female mold (1) having a concave molding surface and a male mold (2) having a convex molding surface are prepared. The male mold or female mold used in the present invention is molded from a general-purpose thermoplastic resin. For example, polypropylene, polyethylene, polystyrene, polycarbonate, polyethylene terephthalate, polyamide, polyacetal, polyvinyl chloride, and nylon 6 can be used. Different resins can be appropriately selected from these resins to form each mold, or the same resin can be selected to form each mold. As the mold forming resin, polypropylene, polystyrene, polyamide or the like is preferably used for reasons such as excellent price, transparency, and moldability. In addition to the injection molding, a known method such as compression molding or vacuum molding can be appropriately employed as a method for forming each mold.

Of the prepared molds, the female mold (1) is filled with the first lens forming material (3) of the lens (A-1 in FIG. 1). Next, the first lens forming material is polymerized in the space (4) formed in combination with the male mold (A-2 in FIG. 1). After the polymerization of the first lens forming material, the male mold and the female mold are opened (B in FIG. 1), and a light shielding material (6) is applied on the convex surface of the first polymer (5) fixed to the male mold. (C in FIG. 1). Here, the center thickness of the first polymer is defined by the distance between the male lens center point (α) and the female lens center point (β). A female mold (1 ′), which is a mold that forms a pair with the mold on which the first polymer is fixed, is filled with the second lens forming material (3 ′) (D-1 in FIG. 1) and polymerized (FIG. 1). 1 D-2). Here, the center thickness of the second polymer is such that the lens center point (β ′) of the female mold which is a mold in which the polymer is not fixed and the lens center of the exposed surface of the first polymer fixed to the male mold. It is defined by the distance to the point (γ).
Similarly, a case where the mold is opened in a state where the second polymer is fixed to the female mold will be described. Among the prepared molds, the female mold (1) is filled with the second lens forming material of the lens (A-1 in FIG. 2). Next, the second lens forming material is polymerized in the space formed in combination with the male mold (A-2 in FIG. 2). After the polymerization of the second lens forming material, the male mold and the female mold are opened (B in FIG. 2), and a light shielding material is applied on the concave surface of the second polymer fixed to the female mold (C in FIG. 2). ). Here, the center thickness of the second polymer is defined by the distance between the male lens center point (α) and the female lens center point (β). The first lens-forming material is filled on the fixed second polymer (D-1 in FIG. 2) and polymerized (D-2 in FIG. 2). Here, the center thickness of the first polymer is determined by the lens center point (α) of the male mold that is a mold in which the polymer is not fixed and the lens center point of the exposed surface of the second polymer fixed to the female mold. It is defined by the distance to (γ ′).
Here, FIG. 1 is an example in which the paired mold is a female mold (third aspect of the present invention), and FIG. 2 is an example in which the paired mold is a male mold (fourth aspect of the present invention). ). When the paired mold is a female mold, the female mold should be a new female mold that is not used if priority is given to the cleanliness of the concave surface of the female mold. In consideration of cost reduction, it is preferable to reuse the already used female mold. On the other hand, if the paired mold is a male mold, the male mold should use a new male mold that is not used if priority is given to the cleanliness of the convex surface of the male mold. In consideration of cost reduction, it is preferable to reuse the already used male mold.

The first and second lens forming materials of the present invention are polymerizable compositions, and conventionally known monomers can be used. For example, when obtaining a hydrous soft contact lens, hydroxyalkyl (meth) Acrylate (especially hydroxyalkyl methacrylate: 2-HEMA), alkylene glycol mono (meth) acrylate, alkylaminoalkyl (meth) acrylate, dimethyl (meth) acrylamide (especially dimethylacrylamide: DMAA), glycerol (meth) acrylate (especially glycerol) Examples include methacrylate: glycerol MA), glycidyl (meth) acrylate, vinyl pyrrolidone, and (meth) acrylic acid. In order to obtain a non-hydrous soft contact lens, a monomer that gives a polymer having a low glass transition point, such as n-butyl (meth) acrylate, decyl (meth) acrylate, or lauryl (meth) acrylate, can be used. In order to obtain an oxygen permeable lens, a monomer such as a silicone-containing alkyl (meth) acrylate, a silicone-containing macromer, or the like can be used in combination with the above monomer. None of the polymerizable compositions that are the first and second lens forming materials has an essential monomer, and the type, composition ratio, and the like can be appropriately selected according to the colored contact lens to be obtained.

In the process of opening the male mold and the female mold of the manufacturing method of the present invention, as a method for reliably controlling the first polymer fixed on the male mold side or the second polymer fixed on the female mold side. (I) Adopting a material having a high adhesive strength with the first polymer as a material of a mold to be fixed, and molding the other mold with a material having a low adhesive strength with the first polymer (For example, in the case of producing a water-containing lens, a hydrophilic monomer is blended in the first lens forming material. Therefore, one type of material is made of a hydrophilic type material such as polyamide. The other mold is made of a hydrophobic mold material such as polypropylene). (II) Created with the same mold material for male and female molds, and some kind of treatment (plasma treatment, UV irradiation, corona discharge treatment, laser irradiation or application of a surfactant, etc.) on the surface of one mold To increase the adhesive strength with the first polymer or to facilitate release. Further, (III) in the production method of the present invention, a method of opening a mold so as to always be selectively fixed to one mold (for example, a mold is opened with a temperature gradient from a male mold to a female mold, and the heat is low. Alternatively, a method in which the first polymer remains selectively may be employed.

The adhesive surface between the surface of the first polymer or the second polymer and the male and female surfaces has an antisymmetric relationship (concave with respect to the convex surface, convex with respect to the concave surface). Usually, the mold can be opened in a state of being selectively fixed to one of the molds. However, the control method described above is a technique that enables more reliable control, and whether or not to adopt it may be determined from comprehensive judgment such as cost.

The space (4) in FIG. 1 is filled with the first lens forming material (3), but there are separate voids for accommodating an excessive amount of the first lens forming material. It may be formed when these are combined. By accommodating an excessive amount of the first lens forming material as a feeder, shrinkage that may occur during the polymerization process can be suppressed. Other methods for avoiding shrinkage during polymerization include a method in which a non-reactive substance that does not participate in polymerization is added in advance to a polymerizable composition that is a lens-forming material, and male and / or female molds shrink. For example, there is a method of using a material molded with a material having sufficient flexibility to absorb. In the production method of the present invention, one surface of the first polymer forms the inner surface of the colored contact lens, and the other surface is a surface covered with the second polymer (7). The surface to be coated with the second polymer does not necessarily have to have a precisely shaped surface, so the male or female mold that will form this surface has sufficient flexibility. It can be absorbed to absorb shrinkage during polymerization.

In addition, a known method can be adopted for the polymerization of the polymerizable composition which is the lens forming material in the present invention. For example, thermal polymerization by heating, photopolymerization irradiated with light such as ultraviolet rays, and a combination thereof can be mentioned. In the case of thermal polymerization, the temperature is gradually raised from around room temperature, and heat in a temperature range of 30 ° C. to 120 ° C. is applied to the lens forming material within a few minutes to a few hours. As the thermal polymerization initiator, persulfates, peroxides, azo initiators, and the like can be suitably used. On the other hand, in the case of photopolymerization, polymerization of the lens forming material proceeds by irradiation with active energy such as ultraviolet rays and electron beams. As the photopolymerization initiator, an alkylphenone-based or acylphosphine oxide-based initiator can be suitably used. These polymerization methods and initiators can be appropriately selected in consideration of the balance between the polymerizable composition as the lens forming material and the mold material.

Next, with reference to FIG. 3, a process of applying a light shielding material to the surface of the first polymer after opening the mold will be described.
After opening the male mold and the female mold, the light shielding object (6) is applied to the exposed surface of the second polymer fixed to the female mold with a desired design to form a pattern by the light shielding object. Is done. The design is composed of any one of dots, lines, planes, or a combination thereof, and can also represent characters, figures, symbols, iris patterns, etc. in addition to simply coloring. As a method for applying the light shielding pattern, a conventional method can be appropriately employed, and screen printing, pad printing, ink jet printing, or the like can be employed. Which coating method is selected is determined in consideration of the physical properties of the light shielding material, the characteristics of the second polymer, the state of the surface to be coated, and the like. After applying the light shield to the second polymer, it is desirable to fix the light shield to the second polymer so that the light shield is not dispersed when filling the first lens forming material. . There are various methods for fixing the light shield (heating, drying, electron beam irradiation, etc.), which can also be selected as appropriate (FIG. 3-i).
After opening the male mold and the female mold, the light shielding object (6) is applied to the exposed surface of the first polymer fixed to the male mold with a desired design to form a pattern by the light shielding object. Is done. The design is composed of any one of dots, lines, planes, or a combination thereof, and can also represent characters, figures, symbols, iris patterns, etc. in addition to simply coloring. As a method for applying the light shielding pattern, a conventional method can be appropriately employed, and screen printing, pad printing, ink jet printing, or the like can be employed. Which coating method is selected is determined in consideration of the physical properties of the light shielding material, the characteristics of the first polymer, the state of the surface to be coated, and the like. After applying the light shield to the first polymer, it is desirable to fix the light shield to the first polymer so that the light shield is not dispersed when filling the second lens forming material. . There are various methods for fixing the light shield (heating, drying, electron beam irradiation, etc.), which can be selected as appropriate (FIG. 3-ii).

A pattern of light shielding material (for example, comprising a continuous transparent portion of the sea portion and a discontinuously colored opaque portion of the island portion) masking the color of the iris surrounding the transparent central visual region applied by the above printing method. The pattern having a sea-island structure is a so-called layer having some thickness in the thickness direction of the colored contact lens between the first and second polymers. It is appropriate that the pattern of the light shielding object has a thickness of about 5 to 15 μm so that it has light shielding properties and can maintain the shape of the colored contact lens.

When manufacturing lenses with iris, in order to conceal the lens wearer's iris and objectively change the color and texture of the pupil, in addition to coloring components, opaque materials such as iron oxide and titanium oxide, and fluid A thickener or the like for controlling the property is used as a light shield. Furthermore, when an appropriate monomer or the like is used, the light shielding material and the first and second polymers can be bonded more firmly. Since the light shielding material is completely sandwiched between the first and second polymer layers, it is possible to effectively suppress the components of the light shielding material from eluting to the lens surface. However, in consideration of the use of the coloring component, it can be said that it is more preferable to add a monomer or the like to the constituent component of the light shielding material to bond the first and second polymers more firmly. .

As described above, a colored transparent lens containing an opaque material can be manufactured. When coloring the entire colored contact lens in the same color, it is only necessary to add a coloring component to the first and / or second lens forming material. When it is desired to show the entire colored contact lens, the production method of the present invention can be used effectively.

The first lens forming material and the second lens forming material are not necessarily different compositions as the lens forming material. For example, in the case of manufacturing a lens with an iris, which will be described later, the same composition as the first lens forming material is applied to the second lens forming material after applying a light shielding material to the exposed surface of the first polymer. It is because it may be used as. On the other hand, when creating multifocal colored contact lenses, it is necessary to form polymers having different refractive indexes, and therefore it is inevitably necessary to use a different polymerizable composition that is a lens forming material. Become.

An example of combining different polymerizable compositions as lens forming materials is to produce colored contact lenses having different hardnesses of the respective polymer layers. Conventionally, two-material contact lenses have been proposed in which the central portion is a hard contact lens and the peripheral portion is a soft contact lens. The characteristics of these two kinds of contact lenses are that the central part is formed with a hard contact lens with excellent visual acuity correction power, and at the same time, the peripheral part is softened to improve the wearing feeling, and the advantages of the hard contact lens and the soft contact lens are improved. It was to provide a contact lens to have. Various manufacturing methods have been proposed. Basically, the manufacturing method has a material distribution of a central portion and an annular peripheral portion. There are two problems with the two-material contact lens. One is how the wearer removes the worn contact lens, and two is that the area where the dissimilar materials are joined together is small and the bonding between the dissimilar materials is weak. As a method of removing the contact lens, generally, the hard contact lens is removed by gathering the upper and lower eyelids toward the center. This is possible because the edge portion of the contact lens is hard. On the other hand, the soft contact lens is bent so that the contact lens is sandwiched between the thumb and forefinger and removed from the eye. However, when removing the two-type contact lens, the hard part does not get in the way to bend like a soft contact lens, and the peripheral part is soft, so the power of the eyelids is like a hard contact lens. It is also difficult to remove.

On the other hand, a case where contact lenses obtained by the manufacturing method of the present invention having different hardnesses are manufactured will be described. The reason why the soft contact lens is inferior in visual acuity correction power than the hard contact lens is because the surface of the soft contact lens follows the unevenness of the wearer's cornea surface. This means that the correction power of astigmatism is inferior. Therefore, the colored contact lens inner surface side (BC side) layer of the present invention is manufactured as a hard layer, and the contact lens outer surface side (FC side) layer is manufactured as a soft layer. The hardness on the inner surface side of the contact lens prevents the contact lens from following the irregularities on the corneal surface, and corrects visual acuity by accumulating tear fluid between the inner surface of the contact lens and the cornea. On the other hand, the contact lens outer surface side can be softened to maintain the feeling of wearing the contact lens, and the contact lens as a whole can be made flexible enough to be sandwiched when the contact lens is removed.

Moreover, the colored contact lens of the present invention does not have a narrow joining area of different materials unlike the conventional two-type contact lens, and has a layered structure in the thickness direction. The power is very high. In this way, it is possible to design a contact lens that is comprehensively excellent in terms of visual acuity correction power, wearing feeling, ease of contact lens removal, durability, and the like.

FIG. 4 shows a sectional view in the diameter direction of the two-layer colored contact lens. As is apparent from this figure, the colored contact lens of the present invention has a colored portion between the first polymer having the inner surface of the contact lens having a predetermined center thickness and the other polymer layer. Recognize. FIG. 3 (i) shows a color on the surface of the second polymer on the FC side, and FIG. 3 (ii) shows a color on the surface of the first polymer on the BC side.

Example 1
The first lens forming material (2-hydroxyethyl methacrylate (HEMA) 59 w / w%, glycerol methacrylate 30 w / w%, ethylene glycol dimethacrylate 0.5 w / w%, glycerin 10 w / w on a female mold having a concave molding surface. The convex molding surface was filled with 23 μl of w%, 2-hydroxy-2-methyl-1-phenyl-propan-1-one (HMPPO) 0.5 w / w% (photopolymerization initiator), LSR = 1.3). Fitted with a plasma-treated male mold provided, irradiated with light (365 nm, 1 mW / cm ² ) for 5 minutes from the female mold side in a nitrogen atmosphere, polymerized the lens forming material, and then separated both molds . The obtained first polymer was attached to the male mold and had a shape similar to a colored contact lens. At this time, the male mold and the female mold were designed so that a polymer layer having a front curvature radius of 6.6 mm, a rear curvature radius of 6.6 mm, a center thickness of 24 μm, and an outer diameter of 10.9 mm was obtained. A light shielding material (2-HEMA 30 w / w%, iron oxide 40 w / w%, titanium oxide 20 w / w%, polyvinylpyrrolidone (PVP (K-30)) 10 w / w%) is exposed on the exposed surface of the first polymer. , Printed on the surface of the first polymer of the lens-like shape attached to the male mold so that the thickness of the colored layer as the light shielding layer is 10 μm, in a blower at about 25 ° C. for 10 minutes I left it alone. The surface of the applied light shield was observed to be dry. 35 μl of a second lens forming material having the same composition as the first lens forming material is placed in a female mold that is paired with a male mold on which the first polymer is fixed, and the first polymer is left in a blower. The attached male mold was fitted, and light (365 nm, 3 mW / cm ² ) was irradiated from the female mold side for 5 minutes in a nitrogen atmosphere to polymerize the second lens forming material. When both molds were separated, the two-layer polymer in which the first polymer and the second polymer were joined adhered to the male mold. When eight lens-shaped two-layer polymers adhering to the male mold were each immersed in 5 ml of purified water, the two-layer polymer contained water and was removed from the male mold. The colored contact lens, which is a two-layered polymer that has been removed from the male mold and softened with water and swelling, was immersed in 5 ml of fresh purified water for 10 minutes at room temperature. The operation of immersing in fresh purified water 5 ml at room temperature for 10 minutes is repeated 5 times to remove the eluting components from the colored contact lens, and 1 colored contact lens is placed in a depression in a PP container containing 1 ml of physiological saline, The hollow of the container was sealed with the multilayer film, and autoclaved at 121 ° C. for 20 minutes. After cooling, the multilayer film was peeled off and the hydrated equilibrium swollen colored contact lens was inspected. As a result, 8 non-strained colored contact lenses having a power of −3.0D, a diameter of 14.2 mm and a center thickness of 110 μm were obtained. A sheet was obtained.
The measuring method of the center thickness of the colored contact lens and the thickness of the colored part was performed as follows. Two razors with sharp teeth were aligned and fixed. When the fixed razor was pressed and cut at a position where the colored contact lens was divided into two equal parts, a strip-shaped lens piece having a width corresponding to the interval between the razor teeth aligned (about 50 μm) could be obtained. . The lens piece is immersed in physiological saline in a plastic petri dish, and the thickness direction of the colored contact lens is photographed using a metal microscope (Nikon ECLIPSE ME600) and an illuminator (L-UEP1). In addition, the center thickness of the lens was calculated by comparing with the size of the reference ruled image taken in the same manner.
Comparative Example 1
An attempt was made to produce colored contact lenses in the same manner as in Example 1. However, the thickness of the first polymer layer produced by the female mold and the male mold was designed to be 60 μm. The thickness of the polymer layer on the BC side became too thick, and 2 out of 8 defective products due to shape defects occurred. At this time, with respect to the non-defective lens as designed, the center thickness of one polymer layer including the inner surface of the lens was 60 μm, and the center thickness of the colored contact lens was 110 μm. The method for measuring the center thickness of the lens was the same as in Example 1.

Example 2
23 μl of the same first lens forming material as in Example 1 was placed in a female mold and fitted with a plasma-treated male mold, and light (365 nm, 1 mW / cm ² ) was applied for 5 minutes from the female mold side in a nitrogen atmosphere. Irradiated to polymerize the first lens forming material and separate the two molds. The obtained first polymer was attached to the male mold and had a lens-like shape. At this time, the male mold and the female mold were designed so that a polymer layer having a front curvature radius of 6.6 mm, a rear curvature radius of 6.6 mm, a center thickness of 15 μm, and an outer diameter of 10.9 mm was obtained. A light shielding material (2-HEMA 30 w / w%, iron oxide 40 w / w%, titanium oxide 20 w / w%, PVP (K-30) 10 w / w%) on the exposed surface of the first polymer as in Example 1. Is printed on the surface of the first polymer having a lens-like shape attached to the male mold so that the thickness of the colored layer, which is a light shielding layer, is 10 μm, and is kept at about 25 ° C. for 10 minutes in a blower. Left unattended. The surface of the applied light shield was observed to be dry. The second lens forming material (polydimethylsiloxane methacrylate 30 w / w%, tris methacrylate 30 w / w%, ethylene glycol dimethacrylate 39 w / w%) is formed into a female mold that makes a pair with the male mold on which the first polymer is fixed. , 0.5 w / w%, 2-hydroxy-2-methyl-1-phenyl-propan-1-one 0.5%, LSR = 1.3) was added to the male mold with the first polymer attached thereto And was irradiated with light (365 nm, 3 mW / cm ² ) from the female mold side for 5 minutes in a nitrogen atmosphere to polymerize the second lens forming material. The second polymer is designed to have a lens shape with a center thickness of 40 μm and an outer diameter of 10.9 mm. When the two molds were separated, the two-layer polymer in which the first polymer and the second polymer were joined adhered to the male mold. Eight lens-shaped two-layer polymers adhering to the male mold were plasma-treated in an oxygen atmosphere in a low-temperature ashing apparatus for 2 minutes and immersed in 5 ml of purified water, respectively. More off. A colored contact lens, which is a two-layered polymer that has been removed from the mold and became soft due to water content and swelling, was immersed in 5 ml of fresh purified water for 10 minutes at room temperature. The operation of immersing in 5 ml of fresh purified water at room temperature for 10 minutes is repeated 5 times to remove the eluting components from the colored contact lens, and the colored contact is formed in the depression in the PP container containing 1 ml of physiological saline as in Example 1. The lens was put in, the hollow of the container was sealed with the multilayer film, and autoclaved at 121 ° C. for 20 minutes. After cooling, the multilayer film was peeled off and the colored contact lens was inspected. As designed, the colored contact made of a good silicone hydrogel material and a water-containing material having a power of −3.0D, a diameter of 14.2 mm, and a center thickness of 110 μm. Eight lenses were obtained. The center thickness of the first polymer layer provided with the inner surface of the lens was 15 μm. The method for measuring the center thickness of the colored contact lens was the same as in Example 1.
Comparative Example 2
An attempt was made to produce colored contact lenses in the same manner as in Example 2. However, the thickness of the first polymer layer was designed to be 60 μm. An attempt was made to produce a colored contact lens of -3.0D, but the size of the finished colored contact lens was unstable, and 3 out of 8 out of specifications occurred. In addition, the measuring method of the center thickness of a lens and the center thickness of the 1st polymer layer provided with a lens inner surface was performed similarly to Example 1. FIG.

Example 3
Using the same first and second forming materials as in Example 1, a colored contact lens having a center thickness T1 of the colored contact lens and a thickness T2 of the first polymer provided with the inner surface of the colored contact lens was obtained (frequency − 3.0D, diameter 14.2 mm). The thickness of the colored layer was about 10 μm. A colored contact lens having a lens center thickness of 50 μm or more and less than 80 μm, wherein T1 / T2 which is a ratio of the center thickness of the first polymer layer provided with the inner surface of the colored contact lens to the center thickness of the colored contact lens is 35% or less. The colored contact lenses that were obtained are shown in Table 1 as Example 3-1 and Example 3-2.
Further, colored contact lenses having a colored contact lens center thickness of 80 μm or more and 200 μm or less and T2 of 40 μm or less are shown as Example 3-3, Example 3-4 and Example 3-5 in Table 1. It was shown to. Table 1 shows the state of the strip-shaped lens pieces cut out from these hydrated colored contact lenses in the same manner as in Example 1 in physiological saline. When the shape of the strip-shaped lens piece remains the same as that of the colored contact lens before cutting, ◎, when it is almost flat, it is warped against the lens shape before cutting. △ when curled, and x when curled.
Comparative Example 3
Using the same first and second forming materials as in Example 1, a colored contact lens having a central thickness T1 of the colored contact lens and a thickness T2 of the first polymer layer provided with the colored contact lens inner surface was obtained (frequency) -3.0D, diameter 14.2 mm). The thickness of the colored layer was about 10 μm. Colored contact lenses having a lens center thickness of 50 μm or more and less than 80 μm and having T1 / T2 of more than 35% are shown in Table 1 as Comparative Example 3-1 and Comparative Example 3-2. Further, colored contact lenses having a lens center thickness of 80 μm or more and 200 μm or less and T2 exceeding 40 μm are shown in Table 1 as Comparative Example 3-3 and Comparative Example 3-4. The state of the strip-shaped lens pieces cut out from these hydrated colored contact lenses in the same manner as in Example 1 in physiological saline was evaluated in the same manner as in Example 3 and shown in Table 1.
In the colored contact lens indicated by ◎ or ◯ in Example 3, the cut-out strip-shaped lens piece maintains an appropriate lens shape, and it is estimated that the stress due to the molding method does not remain in the colored contact lens. It was. On the other hand, the colored contact lens indicated by Δ or × in Comparative Example 3 shows that even if it is in an appropriate lens shape before cutting, the cut-out strip-shaped lens piece cannot retain the lens shape before cutting, and coloring It was estimated that the stress due to the mold manufacturing method remained on the contact lens.

Example 4
An experiment was conducted to examine the retention of the contact lens shape when the contact lens was in a dry state.
2 g of cobalt chloride (2) hexahydrate (Nacalai tex) was weighed and dissolved in 8 ml of purified water (Kyoei Pharmaceutical) to prepare a 20 w / v% solution. After thoroughly wiping off the water of the hydrated colored contact lens (T1 = 110 μm, T2 = 20 μm, base curve (BC) 8.6 mm, frequency −3.0D) with Kimwipe, 1 ml of 20 w / v% It was immersed in the cobalt chloride solution for 1 hour or more. After leaving it to stand at 25 ° C. for an additional hour or longer, remove the contact lens, thoroughly wipe off the moisture with Kimwipe (Cresia), place the contact lens on a wire mesh, and take a picture of the dry state of the contact lens with a digital camera. did. The time at this time was 0 minute. The contact lens was left at 25 ° C., and changes with time of the contact lens were photographed. Images were taken at 5, 10, 15, 20, 25, 30 minutes, 35 minutes, 40 minutes, and 45 minutes after the start of drying. It was found that the contact lens became dry due to the discoloration (blue) of the cobalt chloride reagent incorporated into the contact lens. Even when the dry state of the contact lens progressed with the start of drying, the shape of the contact lens hardly changed, and it was found that the shape stability of the contact lens could be maintained (FIG. 4).
Comparative Example 4
Colored contact lens (T1 = 140 μm, T2 = 100 μm, BC8.6, power −3.0D), single contact lens (center thickness 110 μm, power −3.0D, diameter 14) by the mold manufacturing method of the present invention having no colored portion .2 mm, BC 8.6 mm) and 2WEEK Menicon Duo (manicon, center thickness 160 μm, frequency S-0.25 D / ADD + 0.50 D, diameter 14.5 mm, BC 8.6 mm). In the colored contact lens, with the discoloration (blue) of the cobalt chloride reagent indicating the dry state, the lens edge bent to the BC side, and the shape of the entire contact lens changed to an irregular shape. On the other hand, the lens shape hardly changed in other cases. Compared to a colored contact lens that changes its shape as the drying state progresses even if it has an appropriate lens shape in the hydrated state, the colored contact lens of the present invention is a contact by a mold manufacturing method that is not colored. As with the lens, it was found that even when the dry state progressed, the lens shape retention was excellent. Although not shown, a colored (with iris) contact lens (1 Day Accuview Fine vivid (manufactured by Johnson & Johnson), T1 = 73 μm, T2 = 62 μm, power −9.0D, diameter 14.2 mm, BC 8.5 mm) When the same test was performed using 30 minutes after the start of drying, the lens edge bent to the BC side due to the discoloration (blue) of the cobalt chloride reagent indicating the dry state, and the shape of the entire contact lens became irregular. changed. In addition, the thickness of the colored layer in the colored contact lens and the colored (with iris) contact lens was about 10 μm.

The present invention relates to a colored contact lens having a two-layer structure in the thickness direction and a method for producing the same, and the shape of the lens is obtained by setting the center thickness of a first polymer layer provided with the inner surface of the colored contact lens to a predetermined thickness. By maintaining stability and employing an appropriate material for each layer, it is possible to provide a useful contact lens that solves a problem that cannot be solved by a single material as a whole by combining a plurality of materials.

1, 1 'female mold 2 male mold 3, 3' forming material 4 space 5 first polymer 6 light shield 7 second polymer 8 two-layer polymer α, β lens center point

Claims

A colored contact lens having a center thickness of 80 μm to 200 μm,
A first polymer layer having an inner surface of a contact lens having a center thickness of 5 μm or more and 40 μm or less;
A second polymer layer comprising the outer surface of the contact lens;
The colored contact lens comprising a light shielding pattern portion between the two polymer layers.
A colored contact lens having a center thickness of 50 μm or more and less than 80 μm,
A first polymer layer comprising the inner surface of the contact lens, wherein the lower limit of the center thickness is 5 μm and the upper limit is 35% with respect to the center thickness of the contact lens;
A second polymer layer comprising the outer surface of the contact lens;
A pattern portion of a light shielding material between the two polymer layers;
The colored contact lens comprising:
A space formed by matching a male mold having a convex molding surface and a female mold having a concave molding surface, which are a pair of molds, is filled with the first lens forming material of the contact lens. Polymerize to form a first polymer,
Open the male and female molds to fix the first polymer to the male mold,
Applying a light shielding material to the exposed surface of the first polymer fixed to the male mold;
A second lens forming material of the contact lens is filled into a space formed by matching with a female mold that forms a pair with the male mold on which the first polymer is fixed, and then polymerized. Forming a polymer,
Impregnating a physiological solution into a two-layer polymer obtained by opening a male mold and a female mold;
The manufacturing method of the colored contact lens of Claim 1 or 2.
A space formed by mating a male mold having a convex molding surface and a female mold having a concave molding surface, which are a pair of molds, is filled with a second lens forming material of a contact lens. Polymerize to form a second polymer,
Open the male and female molds to fix the second polymer to the female mold,
Applying a light shielding material to the exposed surface of the second polymer fixed to the female mold;
The first lens forming material of the contact lens is filled and polymerized in a space formed by matching with the male mold that is paired with the female mold on which the second polymer is fixed. Forming a polymer,
Impregnating a physiological solution into a two-layer polymer obtained by opening a male mold and a female mold;
The manufacturing method of the colored contact lens of Claim 1 or 2.