CN109070503B

CN109070503B - Colored contact lenses and methods of making same

Info

Publication number: CN109070503B
Application number: CN201680084404.0A
Authority: CN
Inventors: 林文卿; 李静芳
Original assignee: Hope Falcon Technology Co ltd
Current assignee: Hope Falcon Technology Co ltd
Priority date: 2016-11-08
Filing date: 2016-11-08
Publication date: 2021-03-05
Anticipated expiration: 2036-11-08
Also published as: WO2018085983A1; CN109070503A

Abstract

A sandwich colour contact lens is composed of optical region and transfer printing region consisting of front and back high-molecular polymer layers, colour-carrying layer, colouring agent layer and back high-molecular polymer layer. The colorant layer is compounded between lenses of the same material to form a customized sandwich-type colored contact lens.

Description

Colored contact lenses and methods of making same

Technical Field

The invention relates to a color contact lens and a preparation method thereof, in particular to a sandwich type color contact lens which can be specially manufactured and is completely coated with a pigment and a preparation method thereof.

Background

Since the initial invention of 1950, the commercial use of contact lenses has been for 60 years, and the initial contact lenses are made of hard materials (such as PMMA (polymethyl methacrylate)), because the materials are hard and the oxygen permeability and hydrophilicity of the contact lenses are poor, the contact lenses can be worn for a short time, and obvious foreign body discomfort can be generated. The invention of soft contact lenses in the 70 s was an improved innovation, which was made of a water gel material based on HEMA (2-hydroxyethyl methyl acrylate). Because the material has high water absorption, the material forms soft and high water-bearing property after hydration, greatly improves the wearing comfort, but has low oxygen permeability, can be worn for only 8 to 12 hours every day, and has the pathological changes of corneal hypoxic edema and angiogenesis after long-term wearing. Urban land people are thick, living space is relatively narrow, and heavy learning pressure is added, so that population with abnormal vision is increased rapidly, although the vision can be corrected by wearing glasses, the inconvenience of daily life is caused by wearing glasses, and therefore people can often use contact lenses to correct the vision. Contact lenses are worn directly on the cornea and the adjacent marginal zone or scleral zone of the eye for correcting vision or as a means for shaping the cornea; the development of products is gradually going from the earliest hard materials such as glass and PMMA to hydrophilic HEMA materials, and the development trend in the future is towards Silicon Hydrogel (Silicon Hydrogel) materials which can be worn for a long time.

With the improvement of economic status, people are also driven to improve the beauty and fashion value, so that the vision care products originally seeking correction function have been developed from emphasizing practical function and considering popularity and beauty. Many contact lens manufacturers have also developed both corrective and cosmetic lenses; however, such colored contact lenses (commonly known as "meiji" lenses) are attractive but their safety and problem are not considered sufficiently important, and if improperly colored or worn for extended periods of time, may have the potential risk of loss of color resulting in eye damage. Including redness of the eye, corneal angiogenesis or decreased sensitivity, etc. Others include base curve or diameter irregularities, lens thickness non-uniformities that can contribute to non-smooth flatness of the breathable intake surface and edges, and the like.

The colored contact lenses or colored contact lenses commonly known in the workshop are characterized in that a coloring layer is coated on the surface or inside of the contact lenses, so that the wearer can correct the vision by means of the lenses and can also enhance or change the color and size of the iris of the eyes by means of the coloring layer so as to improve the aesthetic feeling of the eyes, and therefore the colored contact lenses or colored contact lenses are widely popular among people in the world. Currently, the process of inlaying is generally to use Pad printing (Pad Print) method to Print colorant containing pigment on the surface of the contact lens or to coat the lens inside, so as to make the colored contact lens or the dyed contact lens. For example, taiwan patent No. M339691 discloses a layered structure of a gradient coated contact lens, which teaches that a colorant layer is coated between a soft and transparent upper lens and a lower lens to prevent the colorant from directly contacting the eyeball of a wearer or prevent the color loss of the colorant from causing allergy to the eye or scratching the eyeball. In addition, for example, taiwan patent publication No. 201318857a discloses a technology for manufacturing a dyed contact lens, which is to spray, coat or soak an oligomer as a covering material on the surface of a contact lens body of a colored layer (i.e., a colorant layer) containing a colorant, wherein the oligomer covering material comprises Polyhydroxyethylmethacrylate (PHEMA) and a solvent, so as to form a transparent film on the surface of the lens body having the colored layer, and then perform curing molding to volatilize the solvent, thereby obtaining a dyed contact lens having a protective transparent film. Thus, the manufacturing process of the dyed contact lens can be simplified and accelerated.

Taiwan patent publication No. M521191 aims to provide a multi-layered contact lens with enhanced colorant coating properties to improve the stability of the colorant layer coated inside the conventional colored contact lens under durable use. The technical means adopted by the patent comprise: the lens comprises a lens, a lower protective layer and a colorant layer, wherein the colorant layer is compounded between the lens and the lower protective layer, and the lower protective layer and the colorant layer also comprise a compound adhesion layer. The method has high equipment cost and complicated process, and the quality of the hydrophilic material combined on the surface of the contact lens is extremely unstable during the manufacturing, so that the yield of the mass production is high, and the manufacturing cost cannot be reduced.

As described above, it is known to produce tinted contact lenses in which a lens is coated with a colorant layer containing a colorant. But the key point of isolating the direct contact of the pigment in the colorant layer lies in the implementation of the protective layer; more specifically, if the strength of the protective layer is not strong enough, the stability of the colorant layer coated in the lens body is still insufficient under durable use due to frequent repeated bending of the lens body during wearing or cleaning, and the colorant layer is easy to deform and become uneven, the pigment of the colorant is exposed, the protective layer is too thin, and the problem of hole formation is easily caused. However, if the strength of the protective layer is too high, the expansion coefficient is different from that of the lens material, resulting in the problem of lens edge eversion or lens rolling. The protective layer material is not the same as the lens, so that the compatibility is different and strictly speaking, the contact lens is only a skin-attached sandwich color contact lens.

Disclosure of Invention

In view of the above-mentioned problems and disadvantages, it is a primary object of the present invention to improve the oxygen permeability and hydrophilicity of a colored contact lens to improve the wearing safety and comfort of the colored contact lens.

The invention provides a colored contact lens, which comprises a lens body, a lens cover and a lens cover, wherein the lens body comprises a front high polymer polymerization layer with a part of convex surface and a rear high polymer polymerization layer with a part of concave surface; and a coloring pattern structure sandwiched between the front polymer layer and the rear polymer layer, wherein the vertical distance from the coloring pattern structure to the convex surface is greater than 5 μm.

In one embodiment, the front polymer layer and the rear polymer layer are made of the same material.

The coloring pattern structure comprises a color carrier layer; and a colorant layer formed on a specific region of the color carrier layer.

In one embodiment, the materials forming the color carrier layer and the colorant layer respectively comprise at least one hydrophilic and hydrophobic monomer, a dispersant resin, an initiator and a cross-linking agent, and the material forming the colorant layer further comprises a pigment.

In one embodiment, the material comprising the lens body comprises a hydrogel or a silicone hydrogel, and an initiator and a cross-linking agent.

In one embodiment, the color-bearing layer, the colorant, and the lens body form a network interpenetrating structure.

The invention also provides a method for manufacturing the colored contact lens, which comprises the steps of 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 constitute a pigment pattern; dripping a lens material on the first mould; and closing the second mold and the first mold, and waiting for a period of time, so that the lens material penetrates through the color carrier layer and then is subjected to polymerization curing reaction to form the colored contact lens.

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

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

The foregoing description is only an overview of the technical solutions of the present invention, and in order to make the technical means of the present invention more clearly understood, the present invention may be implemented in accordance with the content of the description, and in order to make the above and other objects, features, and advantages of the present invention more clearly understood, the following preferred embodiments are described in detail with reference to the accompanying drawings.

Drawings

FIG. 1 is a cross-sectional view of an embodiment of a colored contact lens according to the present invention.

Fig. 2A-2B are schematic cross-sectional views of an embodiment of a colored contact lens according to the present invention during the manufacturing process.

FIG. 3 is a schematic flow chart illustrating one embodiment of a method for manufacturing a colored contact lens according to the present invention.

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

Detailed Description

The structural features of the colored contact lenses of the invention can be understood from the cross-sectional view of the embodiment shown in fig. 1. 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 is divided into a central optical zone C located at a position corresponding to the pupil and a peripheral zone P located at a position corresponding to the iris and surrounding the central optical zone C. The edge region P of the lens body 1 is composed of a front polymer layer 13 having a partially convex surface 12 and a rear polymer layer 14 having a partially concave surface 15. The colored pattern structure 2 is sandwiched between the front polymer layer 13 and the rear polymer layer 14. The lens body 1 may be made of water gel or silicon water gel.

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 a protective layer in general prior art. In one embodiment, the front polymer layer 13 and the rear polymer layer 14 may be made of the same material, which is different from the prior art that a protective layer is separately formed on a color layer, but the structure of the present invention is not limited thereto.

In one embodiment, the coloring pattern structure 2 includes a color carrier layer 21 and a colorant layer 22 formed at a specific region of the color carrier layer 21. The color carrier layer 21 may be of a material having a surface energy similar to that of the constituent lens body 1. The colorant layer 22 may also have the same kind of material as that constituting the color carrier layer 21, but may have a different composition ratio while additionally containing a pigment to form a colored pattern.

The materials constituting the color carrier layer 21 and the colorant layer 22 may respectively contain at least one of hydrophilic and hydrophobic monomers, an initiator, a crosslinking agent, and a dispersant resin.

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

The invention is implemented by pad printing and point cross polymerization of monomers. To illustrate the manufacturing process of the colored contact lens of the present invention, please refer to the cross-sectional views of the manufacturing process shown in fig. 2A-2B and the manufacturing mold shown in fig. 4, in combination with the manufacturing flow chart shown in fig. 3.

First, in step S1, a pigment composition required for forming the colorant layer 22 is prepared. Next, in step S2, a 2-4 μm color-carrying layer 21 is first pad-printed on the first surface (a concave surface in this embodiment) 31 of the first mold body (the master mold in this embodiment) 3 shown in fig. 4, wherein the color-carrying layer comprises hydrophobic and/or hydrophilic monomers, a dispersant resin, an initiator and a crosslinking agent. After completion, in step S3, a 5-30 μm colorant layer 22, which is also composed of hydrophobic and/or hydrophilic monomers, dispersant resins, initiators, and cross-linking agents, is pad printed, and a toner approved by the United states food and drug administration (US FDA) is added as a pigment for coloring the pattern. Dispersant resins (dispersing agents) suitable for use in the present invention include, but are not limited to, monomers (monomers) or prepolymers (pre polymers) of acrylic resins (acrylic resins), as well as other materials suitable as pigment dispersants, such as: ethyl Methacrylate (HEMA), ethyl methacrylate (HPMA), Methyl methacrylate (acrylic monomer) (Methyl methacrylate-MMA), Glycidyl Methacrylate (GMA), and the like. Toners suitable for use in the present invention include, but are not limited to: c.i.pigment white 6, c.i.pigment Blue 15: 4, c.i.pigment Green 7, c.i.pigment Violet 23, c.i.pigment Yellow 42, c.i.pigment Brown, carbon black, etc. Neither of the two layers is capable of undergoing thermal, Ultraviolet (UV) or similar polymerization reactions. In application, the color pattern may be transferred over a protective layer (not shown) on the first surface 31 of the first mold 3 using pad printing techniques. The color applied is not limited to one. Generally, the applied colors are all three or less. However, more than three types of the compounds are not necessary. Such as more than one color or the resulting pattern requires more than one stencil, may have to be printed or applied in separate passes.

Next, in step S4, a 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 back polymer polymerization layers 13 and 14 of the rim region P and the central optical region C. In application, the first mold 3 may be made of polypropylene (PP) or other material having a surface energy similar to that of the color carrier layer 21, so as to attach the color carrier layer 21 to the first surface 31 thereof during the manufacturing process. The material of the lens body 1 can be water gel or silicon water gel as described above. The hydrogel material typically has a polyacrylic acid monomer, and more particularly may include any conventional hydrogel component such as: ethyl Methacrylate (HEMA), ethyl methacrylate (HPMA), Methyl methacrylate (acrylic monomer) (Methyl methacrylate-MMA), Glycidyl Methacrylate (GMA), combinations thereof, and the like.

The hydrophilic monomer constituting the color carrier layer 21 may also be a component of the aqueous 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 ' -Dimethylaniline (DMA), N ' -diethylacrylamide (N, N ' -diethylacrylamide), N-isopropylacrylamide (N-isopropylpyrrolidone), 2-hydroxyethyl acrylate (2-hydroxymethacrylate), vinyl acetate (vinyl acetate), N-acryloyl morpholine (N-acryloyloxazoline), 2-dimethylaminoethylacrylate (2-dimethylaminoethylacrylate), or a combination thereof. Examples of the hydrophilic monomer used in this example include N, N' -diethylacrylamide, N-vinylpyrrolidone and methacrylic acid (MAA).

The hydrophobic monomer constituting the color-bearing layer 21 may be a silicon-containing monomer and other hydrophobic monomers having a surface energy close to that of the silica hydrogel material, such as acrylates (e.g., methyl Methacrylate/Ethyl Methacrylate) or styrenics. The silicon-containing monomer may also be a silicon hydrogel material for forming the lens body 1, and may be, but not limited to, TRIS (trimethylsiloxane) -2-methacryloxypropylsilane (TRIS (trimethylsiloxy) silylpropylmethacrylate; TRIS (trimethyl-propyl) -methacrylate), bis (trimethylsiloxy) silylpropyl methacrylate (bis (trimethylsiloxy) silylpropyl methacrylate), pentamethyldisiloxane-propylmethacrylate (pentamethyldisiloxane-methylsilylmethacrylate), TRIS (trimethylsiloxy) silylpropylmethacrylate (TRIS (trimethylsiloxy) silylpropyl methacrylate), TRIS (trimethylsiloxy) silylpropyl methacrylate (trimethylsiloxy) propylmethacrylate), TRIS (trimethylsiloxy) propylmethacrylate), TRIS (trimethylsiloxy) propylmethacrylate, trimethylsiloxy) propylmethacrylate (trimethylsiloxy) methacrylate, trimethylsiloxy) propylmethacrylate (trimethylsiloxy) methacrylate (trimethylsiloxy) acrylate, trimethylsiloxy) propylmethacrylate (trimethylsiloxy) acrylate, trimethylsiloxy (trimethylsiloxy) acrylate, trimethylsiloxy (trimethylsiloxy) acrylate, and (trimethylsiloxy) acrylate, trimethylsiloxy, trimethylsil, Tris (dimethylsiloxane) acryloxypropyl silane (tris (dimethylsiloxane)) or a combination of these components.

The radical chain-locking polymerization can be carried out by selecting a photoinitiator or a thermal initiator according to different reaction modes, and the initiators can be any of those known in the art, such as those disclosed in U.S. Pat. No. 6,992,118 and U.S. Pat. No. 5,908,906. The photoinitiator used in one embodiment of the present disclosure is IRGACURE 819 Phenylbis (2, 4, 6-trimethylbenzoyl) phosphine oxide.

Then, after the second mold 4 (male mold in this embodiment) having the second surface 41 (a convex surface matching the first surface 31 in this embodiment) and the first mold 3 are slowly clamped together as shown in fig. 4, and after a waiting time (which may be 30-500 seconds), ultraviolet light (UV) or thermal polymerization is performed in step S5The method cures it. After completion, the hydration process (release) is performed in step S6. When a photoinitiator is used, the radical chain-lock polymerization is preferably carried out at a molecular weight of between 2mW/cm²To 10mW/cm²Under the condition of light irradiation, preferably at a concentration of 2mW/cm²To 5mW/cm²The reaction is carried out under the condition of light irradiation. When a thermal initiator is used, the heat treatment temperature is preferably between 60 ℃ and 120 ℃. Preferably, the light irradiation time or the 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 viewed by the naked eye, it can be seen that its pigment pattern (colorant layer 22 in colored pattern structure 2) is located within the lens with the surface lines intact and without scratches. The colored contact lens of the invention has no convex pattern layer because the pigment is positioned in the lens body 1, so that the eyeball cannot be damaged due to escape when the colored contact lens is used.

The thickness of the front polymer layer 13 can be 5-80 μm or more, as clearly seen in the cross-sectional view (not shown) of the finished colored contact lens 10 using a microtome and a tool microscope. These thickness differences depend on the formulation differences of the hydrophilic and hydrophobic monomers of the color carrier layer 21 and the colorant layer 22 and the design of the waiting time before polymerization.

Table 1 shows examples of formulations of the color carrier layer 21 and the colorant layer 22 with different composition ratios.

TABLE 1

		C01 (color carrier layer)	C02 (color carrier layer)	P01 (colorant layer)
					Hydrophilic monomers	NVP(wt％)	24	40	20
Hydrophobic monomers	SIGMA(wt％)	40	24	34
					Dispersant resins	6007(wt％)	30	30	30
Initiator	819(wt％)	3	3	3
					Crosslinking agent	TMPTMA(wt％)	3	3	3
Toner powder	Black 11(wt％)	-	-	10
						Total (wt%)	100％	100％	100％

In the examples using the formulations shown in table 1 as samples, the thickness variation of the front polymer polymerization layer 13 obtained by applying the samples with different ratios of hydrophilic and hydrophobic monomers and the waiting time before polymerization to the lens body of the hydrogel or the silicone hydrogel is shown in tables 2 and 3.

Table 2 hydrogel lens samples:

table 3 silicone hydrogel lens samples:

the color carrier layer 21/colorant layer 22 in table 1 above contains both hydrophilic monomers and hydrophobic monomers, so that the colored pattern structure 2 becomes an operation platform suitable for glue/silicone glue or any other hydrophilic/hydrophobic lens body material. However, in practice, the hydrophilic monomer or the hydrophobic monomer may be selected as the material of the color carrier layer 21/the colorant layer 22 according to the surface energy characteristics of the lens bulk material to be formed. For example, if the material of the lens body 1 is water gel, the composition of the color carrier layer 21/colorant layer 22 may contain only hydrophilic monomers. Similarly, if the silicone hydrogel is used as the material of the lens body 1, the composition of the color carrier layer 21/colorant layer 22 may only contain hydrophobic monomers.

In addition, the homogeneous polymerization reaction cannot be performed first during the waiting time, and if so, the material monomer cannot penetrate, that is, the thickness of the polymer layer 13 before formation cannot be obtained. The thickness is important similar to the protective layer concept of the prior art, so that the pigment is located in the lens without a protruding pattern layer, and thus the eyeball is not damaged by escaping and falling off during use.

In addition, the transfer printing color carrier layer and the coloring agent layer contain an initiator and a cross-linking agent, and the importance is that the material monomer can form a network interpenetrating structure after polymerization reaction after penetrating through, so that the pattern of the coloring layer can be increased and firmer.

In summary, the present invention provides a sandwich color contact lens and a method for making the same, which mainly comprises an optical zone and a pad printing zone, wherein the pad printing zone further comprises a front polymer polymerization layer, a color carrier layer, a colorant layer, and a rear polymer polymerization layer, wherein the front and rear polymer polymerization layers and the polymer polymerization layer of the optical zone are made of the same material, and thus the lens is formed by using hydrophilic and hydrophobic monomers to mutually penetrate through the phase and wait time design, and then performing polymerization reaction. The colorant layer is compounded between lenses of the same material to form a customized sandwich-type colored contact lens. The thickness of the front polymer layer of the colored contact lens manufactured by the method provided by the invention can be thicker than that of the traditional colored contact lens, so that the pigment of the colored pattern structure can be ensured not to contact with eyeballs to cause damage.

Although the present invention has been described with reference to a preferred embodiment, it should be understood that various changes, substitutions and alterations can be made herein without departing from the spirit and scope of the invention as defined by the appended claims.

Claims

1. A method of manufacturing a colored contact lens, comprising:

forming a color-carrying layer on one surface of a first mold, wherein the color-carrying layer is made of materials comprising at least one hydrophilic monomer, at least one hydrophobic monomer, a dispersing agent resin, an initiator and a cross-linking agent;

forming a colorant layer on a specific region of the color-carrying layer on the first mold to form a pigment pattern, wherein the colorant layer comprises at least one hydrophilic monomer, at least one hydrophobic monomer, a dispersant resin, an initiator, a cross-linking agent and a pigment;

dripping a lens material on the first mold;

and closing the second mold and the first mold, allowing the lens material to penetrate through the color carrier layer for a waiting time to form a polymer pre-polymerization layer between the color carrier layer and the first mold, and performing polymerization curing reaction to form the colored contact lens.

2. The method of claim 1, wherein the lens material comprises a hydrogel monomer or a silicone-containing hydrogel monomer, the initiator, and the cross-linking agent.

3. The method of claim 2, wherein the color carrier layer, the colorant layer and the lens material are polymerized in one step in the curing polymerization reaction to complete a network interpenetrating structure.

4. The method of claim 1, wherein the first mold is a master mold, and the color-bearing layer and the colorant are formed on a concave surface of the master mold by pad printing.

5. The method according to claim 1, wherein the thickness of the pre-polymer layer after the curing polymerization reaction is greater than or equal to 5 μm.

6. The method of claim 1, wherein the curing polymerization is a photopolymerization.

7. The method of claim 6, wherein the waiting time is 30-500 seconds.

8. A colored contact lens produced by the method of any one of claims 1 to 7, comprising:

a lens body which is divided into a central optical area and an edge area surrounding the central optical area and is provided with a convex surface and a concave surface, wherein the edge area comprises a front polymer polymerization layer with part of the convex surface and a rear polymer polymerization layer with part of the concave surface; and a coloring pattern structure sandwiched between the front polymer layer and the rear polymer layer, wherein the thickness of the front polymer layer is greater than 5 μm.

9. The colored contact lens of claim 8, wherein the anterior polymeric layer and the posterior polymeric layer are made of the same material.

10. The colored contact lens of claim 9, wherein the colored pattern structure comprises:

a color-bearing layer having the same kind of material as that constituting the lens body; and

a colorant layer formed on the color-bearing layer, having the same kind of material as that constituting the color-bearing layer, and additionally containing a pigment.

11. The colored contact lens of claim 10, wherein the materials comprising the lens body, the color carrier layer, and the colorant layer comprise at least one hydrophilic and hydrophobic monomer, respectively.

12. The colored contact lens of claim 11, wherein the materials forming the color carrier layer and the colorant layer further comprise a dispersant resin, and the materials forming the lens body, the color carrier layer, and the colorant layer further comprise an initiator and a cross-linking agent, respectively.

13. The colored contact lens of claim 12, wherein the color carrier layer, the colorant and the lens body form a network interpenetrating structure.