TWI588564B - Color contact lens and method for making same - Google Patents

Description

Color contact lens and its preparation method

BACKGROUND OF THE INVENTION 1. Field of the Invention This invention relates to colored contact lenses and methods of making the same, and more particularly to a sandwich-type colored contact lens that can be tailored to completely coat a colorant and a method of making the same.

Since the invention of contact lenses in early 1950, it has been commercialized for 60 years. The original contact lenses were made of hard materials (such as PMMA polymethyl methacrylate), due to their hard material, plus The oxygen permeability and hydrophilicity of the body are not good, so that the contact lens can be worn for a short time, and a significant foreign body discomfort is generated. The invention of soft contact lenses in the mid-1970s is a progressive reform made of a HEMA (2-hydroxyethyl methacrylate) based hydrocolloid. Due to its high water absorption, the material forms a soft, high water-containing property after hydration, which greatly enhances the wearing comfort, but its oxygen permeability is still low, and it can only be worn for 8 to 12 hours a day. Postpartum corneal hypoxic edema and neovascularization often occur. Taiwan’s small population is thick and the living space is relatively small. Coupled with the heavy pressure of entering school, the abnormal population of visual acuity is rapidly increasing. Although abnormal vision can be corrected by wearing glasses, wearing glasses often causes inconvenience in daily life, so people often meet Use contact lenses for vision correction. Contact lenses are worn directly on the cornea and adjacent marginal or scleral areas of the eye to correct vision or as a device for Orthokeratology. The development of the product has gradually evolved from the earliest hard materials such as glass and PMMA to hydrophilic. The HEMA material, and the future trend is towards the durable silicone hydrogel.

As the economic situation improves, it also drives the public's promotion of beautiful fashion values. Therefore, the vision health care products that originally appealed to the corrective function have shifted from emphasizing practical functions to taking into account the development direction of popular aesthetics. Many contact lens manufacturers have also developed corneal color-changing lenses and make-up lenses that are both corrective and aesthetically pleasing; however, such colored contact lenses (commonly known as lenses) can add beauty but his safety and problems have not received enough attention. If it is improperly dyed or worn for a long time, it may have the potential to cause damage to the eye caused by pigmentation. Including redness, corneal angiogenesis or decreased sensitivity. Others including base arc or diameter inconsistent specifications, uneven lens thickness may cause the breathable film surface and edges are not smooth and flat.

Colored contact lenses or dyed contact lenses, which are commonly referred to in the workplace, are coated with a colored layer on the surface or inside of the contact lens. In addition to correcting the vision with the lens, the wearer can also be attached with a colored layer to enhance or Change the color and size of the iris of the eye to enhance the beauty of the eyes, so it is widely loved by the world. At present, the inlay process generally uses a pad printing method to attach a colorant-containing coloring agent to the lens surface of the contact lens or to the inside of the lens to make the colored contact lens or Dyeing contact lenses. For example, Taiwan Patent No. M339691 discloses a layer structure technology of a layered coated contact lens, which teaches that a colorant layer is coated between a soft and transparent upper lens and an underlying lens to avoid direct coloring agent. Contact the wearer's eyeballs, or avoid color fading that can cause eye irritation or scratches the eye. In addition, for example, Taiwan Patent No. 201318857A discloses a technique for producing a dyed contact lens, which is directed to a surface of a contact lens body containing a colored layer of a color material (ie, a colorant layer), which is sprayed, coated or immersed as a covering material. An oligopolymer comprising a polyhydroxyethyl methacrylate (PHEMA) and a solvent to form a transparent surface of the mirror body having the color layer The film is then subjected to solidification molding to volatilize the solvent to obtain a dyed contact lens having a protective transparent film. By doing so, the manufacturing process of the dyed contact lens can be simplified and speeded up.

Taiwan Patent No. M521191, the purpose of which is to provide a multi-layer contact lens for enhancing color coating coverage for improving the stability of a coloring agent layer coated inside a conventional colored contact lens under endurance use. The technical means adopted by the patent includes: a lens, a lower protective layer and a colorant layer, the colorant layer being composited between the lens and the lower protective layer, wherein the lower protective layer and the colorant layer further comprise a composite one Adhesive layer. The method has high equipment cost and cumbersome process, and the quality of the hydrophilic material combined with the surface of the contact lens is extremely unstable during the manufacture, resulting in a high mass production defect rate and a low manufacturing cost.

From the above, it has been known that a dyed contact lens made by coating a coloring agent-containing coloring agent layer in a lens is known. However, the direct contact of the colorant in the insulating colorant layer is mainly due to the implementation of the protective layer; more specifically, since the protective layer is like the wall of the lens, if the strength is insufficient, the wearer can wear or clean the process. Because the mirror body is repeatedly bent repeatedly, the stability of the colorant layer coated in the lens body under endurance is still insufficient, so that the colorant layer is easily deformed and not flattened, the pigment of the color material is exposed, and the protective layer is Too thin and easy to generate holes. However, if the strength of the protective layer is too large, and the expansion coefficient is different from that of the lens material, the lens edge eversion or the lens winding problem is formed. And the material of the protective layer is not the same material of the lens, not only the compatibility is different, but strictly speaking, it is only a skin-type sandwich color contact lens.

In view of the above-mentioned problems and lack of problems to be solved, how to improve to achieve high oxygen permeability and hydrophilicity to enhance the safety and comfort of wearing colored contact lenses is the main purpose of the development of the case.

The present invention provides a colored contact lens comprising a lens body comprising a front polymer layer having a partially convex surface and a rear polymer layer having a partially concave surface; and a color map The structure is a colored pattern structure sandwiched between the front polymer layer and the rear polymer layer, wherein the vertical distance of the colored pattern structure to the convex surface is greater than 5 μm.

In one embodiment, the front polymer layer and the post polymer layer are composed of the same material.

The coloring pattern structure includes a color carrier layer; and a coloring agent layer formed in a specific region of the color carrier layer.

In one embodiment, the materials constituting the color layer and the color former layer respectively comprise at least one hydrophilic and hydrophobic monomer, a dispersant resin, a starter and a cross-linking agent, and the material forming the colorant layer further includes pigment.

In one embodiment, the material comprising the lens body comprises a water gel or a hydrophobic glue, together with an initiator and a crosslinker.

In one embodiment, the color carrier layer, colorant, and lens system form a network interpenetrating structure.

The invention also provides a method for manufacturing a colored contact lens, comprising: forming a color carrier layer on the surface of the first mold; forming a colorant layer on a specific region of the color carrier layer on the first mold to form a pigment pattern; The lens material is dropped onto a mold; the second mold is closed with the first mold, and then waited for a period of time, so that the lens material penetrates the color carrier layer and then undergoes polymerization curing reaction to form a colored contact lens.

In one embodiment, the color-carrying layer, the colorant, and the lens material are subjected to a one-time polymerization in a curing polymerization reaction to complete a network interpenetrating structure.

In one embodiment, the first mold is a master mold, and the color carrier layer and the colorant are formed on the concave surface of the master mold by a pad printing technique.

The above description is only an overview of the technical solutions of the present invention, and the above-described and other objects, features and advantages of the present invention can be more clearly understood. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, preferred embodiments will be described in detail with reference to the accompanying drawings.

10‧‧‧Color contact lenses

1‧‧‧ lens body

12‧‧‧ convex surface

13‧‧‧Prepolymer layer

14‧‧‧After polymer layer

15‧‧‧ concave surface

2‧‧‧Colored pattern structure

21‧‧‧Carrier layer

22‧‧‧Colorant layer

3‧‧‧First mould

31‧‧‧ first surface

4‧‧‧Second mold

41‧‧‧ second surface

C‧‧‧Central Optical Zone

P‧‧‧Edge Area

G‧‧‧Vertical distance

BRIEF DESCRIPTION OF THE DRAWINGS Figure 1 is a cross-sectional view showing the construction of an embodiment of a colored contact lens in accordance with the present invention.

2A-2B are cross-sectional views of an embodiment of a colored contact lens in accordance with the present invention during manufacture.

3 is a flow chart showing an embodiment of a method of manufacturing colored contact lenses in accordance with the present invention.

4 is a schematic cross-sectional view of a mold that can be used to make the colored contact lenses of the present invention.

The structural features of the colored contact lenses of the present invention can be understood from the cross-sectional views of the embodiment shown in FIG. The colored contact lens 10 includes a lens body 1 and a colored pattern structure 2. The lens body 1 has a convex surface 12 and a concave surface 15, and can be further divided into a central optical zone C located at a position relative to the pupil, and an edge zone P surrounding the central optical zone C at a position relative to the iris. The edge region P of the lens body 1 is composed of a front polymer layer 13 having a partial convex surface 12 and a rear polymer layer 14 having a partial concave surface 15. The colored pattern structure 2 is interposed between the front polymer layer 13 and the rear polymer layer 14. The lens body 1 can be made of a material such as water gel or hydrophobic glue.

In particular, the vertical distance G of the colored pattern structure 2 to the convex surface 12 may be greater than 5 μm, which is greater than the thickness of the protective layer in the prior art. In addition, in an embodiment, the front polymer layer 13 and the rear polymer layer 14 may be the same material, but different from the conventional technique in which a protective layer is generally formed on the colored layer, but the present invention The structure is not particularly limited.

In an embodiment, the colored pattern structure 2 includes a color carrier layer 21 and a color former layer 22 formed in a specific region of the color carrier layer 21. The color carrier layer 21 may have a material that is close to the surface energy constituting the lens body 1. The colorant layer 22 may also have the same kind of material as the constituent color-carrying layer 21, but may have different composition ratios while additionally containing a pigment to form Into a colored pattern.

The material constituting the color layer 21 and the coloring agent layer 22 may contain at least one of a hydrophilic and a hydrophobic monomer, a starter, a crosslinking agent, and a dispersant resin, respectively.

In one embodiment, the color carrier layer 21, the colorant layer 22, and the lens body 1 form a network interpenetrating structure.

The practice of the present invention is accomplished by pad printing and monomeric point-to-point polymerization. To illustrate the manufacturing process of the colored contact lens of the present invention, please refer to the cross-sectional view of the manufacturing process shown in FIGS. 2A-2B and the manufacturing mold of FIG. 4 in conjunction with the manufacturing flow chart of FIG.

First, in step S1, the pigment composition required to form the color former layer 22 is first prepared. Next, in step S2, a first surface (in this embodiment, a concave surface) 31 of the first mold body (in this embodiment, a concave surface) 3 as shown in FIG. 4 is first printed with a layer of 2-4 μm. The color carrier layer 21 contains components including a hydrophobic and/or hydrophilic monomer, a dispersant resin, an initiator, and a crosslinking agent. After completion, in step S3, the 5-30 μm colorant layer 22 is further printed, and the composition thereof is also a hydrophobic and/or hydrophilic monomer, a dispersant resin, a starter and a cross-linking agent, and additionally added to the United States. The toner approved by the US Food and Drug Administration (US FDA ) is used as a pigment for the coloring pattern. Dispersing agents suitable for use in the present invention include, but are not limited to, monomers or prepolymers of acrylic resins, and other materials suitable as pigment dispersants, for example: Ethyl acrylate (HEMA), ethyl methacrylate (HPMA), methyl methacrylate (MMA), Glyceryl methacrylate (GMA), and the like. Toners suitable for use in the present invention include, but are not limited to, CIpigment white 6, CIpigment Blue 15:4, CIpigment Green 7, CIpigment Violet 23, CIpigment Yellow 42, CIpigment Brown, carbon black, and the like. Neither layer can perform thermal, ultraviolet (UV) or similar polymerization. In application, the color pattern can be transferred over the protective layer (not shown) on the first surface 31 of the first mold 3 by pad printing techniques. The color to be applied is not limited to one. Generally, the colors applied are less than three. But more than three, no matter what. If more than one color or formed graphic requires more than one template, it may be necessary to print or apply it in multiple steps.

Next, in step S4, the contact lens material formulation is poured into the first mold 3 to form the raw material of the lens body 1 in the front and rear polymer layers 13, 14 and the central optical zone C of the edge region P. . In application, the first mold 3 may be made of polychloropropene (PP) or other material having similar surface free energy to the material of the color carrier layer 21, so as to ensure that the carrier layer 21 is actually attached to the first layer during the manufacturing process. Surface 31. The material of the lens body 1 may be a water gel or a hydrophobic glue as described above. The material of the water gel generally has a polyacrylic acid monomer, and more specifically may include any conventional water gel component such as ethyl methacrylate (HEMA), ethyl methyl crotonate (HPMA), methyl group. Methyl methacrylate (MMA), Glyceryl methacrylate (GMA), combinations thereof, and the like.

The hydrophilic monomer constituting the color carrier layer 21 may also be a component option of the water gel constituting the lens body 1, and may be, but not limited to, hydroxyethyl methacrylate (HEMA), methacrylic acid (methacrylic acid; MAA), N-vinyl pyrrolidone (NVP), N,N'-dimethylaniline (DMA), N,N'-diethyl acrylamide (N,N'-diethylacrylamide), N-isopropylacrlamide, 2-hydroxyethyl acrylate, vinyl acetate, N-propylene hydrazide (N -acryloymorpholine), 2-dimethlaminoethyl acrylate, or a combination of these. The hydrophilic monomers used in this embodiment are N,N'-diethylacrylamide, N-vinylrrolidone, and methacrylic acid (MAA).

The hydrophobic monomer constituting the color carrier layer 21 may be a ruthenium-containing monomer and other hydrophobic monomers similar to the surface free energy of the hydrophobic rubber material, such as acrylates (such as methyl methacrylate/ Ethyl Methacrylate or styrene. The ruthenium-containing monomer may also be a material option of the hydrophobic glue constituting the lens body 1, and may be, but is not limited to, Tris(trimethylsiloxy)silylpropyl methacrylate (TRIS), bistrimethylsulfoxane-propylmethyl decane bis (bis(trimethylsiloxy)) Trimethylsiloxy)methylsilylpropyl methacrylate), pentamethyldisiloxanepropyl methacrylate, pentamethyldisiloxanyl methylmethacrylate, tris(trimethylhydrazine) Tris(trimethylsiloxy)silylpropyloxyethyl methacrylate, tris(trimethylsiloxy)silylpropyl methacryloxyethylcarbamate; TSMC for short , tris(trimethylsiloxane)-tris(trimethylsiloxy)silypropyl glycerol methacrylate; referred to as SIGMA), tris(polydimethyloxane) propyl decane acrylate (tris) (polydimethylsiloxy)silylpropyl methacrylate), or a combination of these.

The free-radical chain-locking polymerization may be carried out using a photoinitiator or a hot-starting agent, which may be any of the prior art known initiators, such as disclosed in U.S. Patent No. 6,992,118 and U.S. Patent No. 5,908,906. of. The photoinitiator used in one embodiment of the present invention is IRGACURE 819 Phenylbis(2,4,6-trimethylbenzoyl)phosphine oxide.

Thereafter, the first mold 3 is retarded by the second mold 4 (the male mold in this embodiment) having the second surface 41 (which is a convex surface of the first surface 31 in this embodiment) as shown in FIG. After the mold is closed, after a waiting time (which may be 30 to 500 seconds), in step S5, it is cured by ultraviolet light (UV) or thermal polymerization. After completion, the hydration process (release) is performed in step S6. When a photoinitiator is used, preferably, the radical chain-locking polymerization is carried out under a light condition of between 2 mW/cm ² and 10 mW/cm ² , more preferably between 2 mW/ The reaction was carried out under light conditions of between ² and 5 mW/cm ² . When a hot initiator is used, preferably, the heat treatment temperature is between 60 ° C and 120 ° C. Preferably, the illumination time or heat treatment time is between 10 minutes and 2 hours, and more preferably between 30 minutes and 2 hours.

When the finished colored contact lens 10 is observed with the naked eye, it can be seen that the pigment pattern (the coloring agent layer 22 in the colored pattern structure 2) is located in the lens, and the surface line is intact without missing marks. The colored contact lens of the present invention has no embossed pattern layer because its pigment is located inside the lens body 1, and therefore does not cause damage to the eyeball due to falling off during use.

The lens of the completed color spectacles 10 is matched with a microtome and a tool microscope, and it can be clearly seen from the cross-sectional view of the obtained color lens (not shown) that the front polymer layer 13 can have a thickness of 5 to 80 μm or more. . These thickness differences depend on the difference in the ratio of the hydrophilicity of the carrier layer 21 to the colorant layer 22 and the waiting time before polymerization.

Table 1 shows examples of formulations of the carrier layer 21 and the colorant layer 22 in different component ratios.

In the examples using the formulation shown in Table 1 as the sample, the difference in the ratio of the different hydrophilic and hydrophobic monomers and the waiting time before polymerization are applied to the thickness of the front polymer layer 13 obtained from the lens body of the water gel or hydrophobic glue. Changes are listed in Tables 2 and 3.

The composition of the color layer 21/colorant layer 22 in Table 1 above contains both a hydrophilic monomer and a hydrophobic monomer, so that the colored pattern structure 2 can be applied to both water/hydrophobic glue or any other hydrophilicity. / Operating platform for hydrophobic lens body material. However, in practice, a hydrophilic monomer or a hydrophobic monomer may be separately selected as the material of the color carrier layer 21/colorant layer 22 for the characteristics of the surface free energy of the lens body material to be formed. For example, if water gel is used as the material of the lens body 1, the composition of the color carrier layer 21/colorant layer 22 may contain only hydrophilic monomers. Similarly, if the hydrophobic glue is used as the material of the lens body 1, the composition of the color carrier layer 21/colorant layer 22 may contain only hydrophobic monomers.

Further, the homopolymerization reaction cannot be carried out first in the waiting time, and if so, the material monomer cannot be penetrated, that is, the thickness of the front polymer layer 13 cannot be formed. This thickness is of similar importance to the protective layer in the prior art, so that the pigment is located inside the lens without a protruding pattern layer, so that the eyeball is not damaged by the fall.

In addition, both the carrier layer and the colorant layer of the pad printing contain an initiator and a cross-linking agent, and the importance is that after the monomer of the material is penetrated, a network interpenetrating structure can be formed after the polymerization reaction, so that it is more capable. Increasing the color layer pattern is more stable.

In summary, the present invention provides a sandwich color contact lens and a method for fabricating the same, comprising an optical zone and a pad printing zone, wherein the pad printing zone further comprises a front polymer layer, a color carrier layer, a colorant layer, and a post polymer polymerization. The layer, wherein the polymer layer of the front and rear polymer layers and the polymer layer of the optical zone are the same material, so that the hydrophobicity monomer is used to penetrate the phase and the waiting time is designed, and then the lens is formed by polymerization. The colorant layer is composited between lenses of the same material to form a specialized sandwich type colored contact lens. The color contact lens produced by the method provided by the invention has a thickness of the front polymer layer which is thicker than that of the conventional color contact lens, so that the pigment of the colored pattern structure can be prevented from being damaged by contact with the eyeball.

The above is only a preferred embodiment of the present invention, and is not intended to limit the present invention in any way. Although the present invention has been disclosed in the above preferred embodiments, In the present invention, those skilled in the art can make some modifications or modifications to the equivalent embodiments by using the methods and technical contents disclosed above without departing from the scope of the present invention. In the content of the technical solutions of the present invention, any simple modifications, equivalent changes and modifications made to the above embodiments in accordance with the technical scope of the present invention are still within the scope of the technical solutions of the present invention.

10‧‧‧Color contact lenses

1‧‧‧ lens body

12‧‧‧ convex surface

13‧‧‧Prepolymer layer

14‧‧‧After polymer layer

15‧‧‧ concave surface

2‧‧‧Colored pattern structure

21‧‧‧Carrier layer

22‧‧‧Colorant layer

C‧‧‧Central Optical Zone

P‧‧‧Edge Area

G‧‧‧Vertical distance

Claims (14)

A method for manufacturing a colored contact lens, comprising: forming a layer of a color carrier on a surface of a first mold; forming a colorant layer on a specific region of the carrier layer on the first mold to form a pigment pattern Dipping a lens material onto the first mold; clamping a mold with the first mold by a second mold, and then waiting for a period of time, so that the lens material penetrates the color carrier layer after the carrier layer Forming a front polymer layer between the first molds, and performing a curing polymerization reaction to form a colored contact lens; wherein the material forming the color layer and the colorant layer respectively comprises at least one hydrophilic monomer and One or a combination of at least one hydrophobic monomer. The method for manufacturing a contact lens according to claim 1, wherein the material for forming the color layer and the colorant layer further comprises a dispersant resin, a starter and a cross-linking agent, respectively, and the coloring is formed. The material of the agent layer further includes a pigment. The method of manufacturing a contact lens according to claim 2, wherein the lens material comprises a water-colloid monomer or a water-containing gelatin monomer, the initiator, and the cross-linking agent. The method for producing a contact lens according to claim 3, wherein the color carrier layer, the colorant layer and the lens material are subjected to one-time polymerization in the curing polymerization reaction to complete a network interpenetrating structure. The method of manufacturing a contact lens according to claim 1, wherein the first mold is a master mold, and the color layer and the colorant are formed on one concave surface of the master mold by a pad printing technique. The method for producing a contact lens according to claim 1, wherein the thickness of the prepolymer layer after the curing polymerization reaction is 5 μm or more. The method for producing a contact lens according to claim 1, wherein the curing polymerization reaction is a photopolymerization reaction. The method of manufacturing a contact lens according to claim 7, wherein the waiting time is about 30 to 500 seconds. A color contact lens comprising: a lens body, which is divided into a central optical zone and an edge region surrounding the central optical zone, and has a convex surface, a concave surface, wherein the edge zone comprises a portion having a portion of the convex surface a front polymer layer, and a post polymer layer having a portion of the concave surface; and a colored pattern structure interposed between the front polymer layer and the rear polymer layer, wherein the prepolymer The thickness of the polymeric layer is greater than 5 μm. The color contact lens according to claim 9, wherein the front polymer layer and the rear polymer layer are made of the same material. The colored contact lens of claim 10, wherein the colored pattern structure comprises: a color carrier layer having the same kind of material as the lens body; and a colorant layer formed on the color carrier layer Above, it has the same kind of material as the composition layer, and additionally contains a pigment. The colored contact lens of claim 11, wherein the material constituting the lens body, the color layer and the colorant layer respectively comprises at least one hydrophilic and hydrophobic monomer. The color contact lens of claim 12, wherein the material constituting the color layer and the colorant layer further comprises a dispersant resin, and constitutes the lens body, the color layer and the colorant. The materials of the layer further comprise a starter and a crosslinker, respectively. The color contact lens of claim 13, wherein the color carrier layer, the colorant and the lens system form a network interpenetrating structure.