TW202116832A - Compositions and methods for producing cosmetic contact lens - Google Patents

Abstract

The present invention relates to compositions and methods for producing cosmetic contact lenses. The invention involves adding Tween^® 60 surfactant into the polymerizable composition at an amount substantially higher than 0.5% by weight and substantially lower than 2.0% by weight based on the total weight of the composition, thereby overcoming the problem of incompatibility between hydrophobic ink material and hydrophilic monomers which often occurs during the manufacturing process of contact lenses.

Description

Composition and method for making beauty lens

The present invention relates to a composition and method for making contact lenses, and more particularly to a polymerizable composition for making beauty lenses, and a method for using the polymerizable composition to make beauty lenses.

In recent years, the rapid development of technology products, countless 3C products have greatly changed the past lifestyles, smart phones, tablets, laptops, TVs, the human eye is always from one screen to another screen, and myopia gradually It has become a civilization disease of modern people. As the myopia population increases, the demand for contact lenses also increases. Contact lenses have been widely used for vision correction, and with the advancement of contact lens manufacturing technology, contact lenses of different shapes or colors have also been designed, and there are new products of corneal color lenses and beauty lenses that have both correction and beauty. Born. Coupled with breakthroughs in contact lens materials, the functionality, comfort, and convenience brought by contact lenses will drive growth opportunities in the contact lens market. Contact lenses are no longer just a single purpose for correcting vision, they can also change the color of the iris or expand the shape of the iris, making the eyes look brighter and deeper. Therefore, they are favored by female consumers.

From general contact lenses to corneal lenses or cosmetic lenses that have both correction and beauty, the process technology continues to evolve. How to effectively master the functions of correction and beauty, and have both wearing comfort and safety, and expand Its scope of application is the goal of major contact lens manufacturers. Contact lenses can be roughly divided into soft contact lenses and hard contact lenses based on the materials they are made of. Among them, soft disposable contact lenses made of water gel or silicone gel are the mainstream. The manufacturing methods of soft disposable contact lenses can be roughly divided into three types. The lathe cutting method is similar to the manufacturing process of hard contact lenses. It involves fixing a cylindrical lens blank (commonly known as a lens button) on an automated lathe, using a diamond knife to turn into a lens with inner and outer curved surfaces, and then proceed Edge grinding and polishing, and then soak the lens in an aqueous buffer solution for hydration and expansion to obtain the finished lens. Spin casting involves injecting a liquid monomer material into a rotating mold, using the centrifugal force of the mold rotation and the surface tension of the liquid to form a uniform film, and then heating or applying light to solidify the monomer material into a shape, and then hydrate it. Finished lens. Cast molding involves injecting a liquid monomer material into a pre-designed lower mold, then using the corresponding upper mold to press and apply heat or light to solidify the lens, then demold and rehydrate Finished lens. Because the injection molding method has the advantages of rapid production, suitable for mass production, low cost, and high lens smoothness yield, the current disposable contact lenses are mostly made by injection molding. The injection molding method can be divided into dry injection molding and wet injection molding. The main difference between the two is that the latter first polymerizes and cures monomers in an environment of hydrophilic solvents such as glycerin, and then hydrates them. As a finished lens, the expansion coefficient of the contact lens can be reduced during the manufacturing process, and it has the advantages of small dimensional variability and precise control of the lens power.

Beauty lenses can be made by wet injection molding. Generally, an ink blended with a pigment is prepared first and the ink is printed on the surface of the mold by a transfer process (pad printing) to form an annular pattern. Then, the liquid hydrophilic monomer is injected into the mold, pressed to solidify and shape the lens, and then hydrated to form the finished lens after demolding. The finished beauty lens is shown in FIG. 1, which has a circular arc sheet shape and defines an optical zone 10 located in the center of the lens and allowing light to enter, and a pattern zone 11 surrounding the optical zone 10 and printed with ink. However, since the cosmetic lens needs to be made into the monomer solution to penetrate and cover the ink, the pigment can be embedded in the lens after curing and forming. In the pretreatment of ink preparation, it is usually necessary to use highly viscous resins to disperse pigments, but these resins are mostly hydrophobic polymers. In contrast, the solvents used in the wet injection molding process are all highly hydrophilic. Therefore, the problem of incompatibility between the hydrophobic ink, the hydrophilic monomer and the solvent often occurs when the lens is made, which further affects the quality of the lens and reduces the yield rate.

Therefore, there is a strong demand in the industry for improving the manufacturing process of soft beauty lenses to increase the manufacturing yield of the lenses.

In order to meet the above-mentioned industrial needs, the inventor of this case has devoted himself to the research and development of the wet injection molding method for soft beauty lenses. The inventor of the present case noticed that although it is a well-known technology to reduce the surface tension between hydrophilic and hydrophobic materials by the amphoteric chemical properties of surfactants to promote the compatibility of the two, it has been verified in practice. Many commonly used surfactants cannot effectively improve the incompatibility between hydrophobic inks and hydrophilic monomers and solvents. What's more, the surfactants available for making contact lenses must be those that do not irritate or harm the wearer's eyes and meet the grade of medical equipment, and the choices are quite limited. The inventor of the present case unexpectedly discovered that a specific ratio of Tween ^®- based surfactant is added to the polymerizable composition used to make cosmetic lenses, that is, the addition is substantially higher than 0.5% by weight and less than 2.0% by weight. Tween ^® 60 surfactant, such as about 1.0% by weight of Tween ^® 60 surfactant, can effectively overcome the above-mentioned industrial problems and significantly improve the manufacturing yield of beauty lenses.

Therefore, according to the first aspect of the present invention, it provides a polymerizable composition for making cosmetic lenses, which comprises: about 60 to 70% by weight of hydrophilic monomers suitable for making contact lenses; substantially higher than 0.5% by weight and less than 2.0% by weight of polyethoxy (20) sorbitol monostearate surfactant (Tween ^® 60); about 0.5-2% by weight of initiator; about 0.5-1% by weight The crosslinking agent; and the rest is made up with a hydrophilic solvent.

In a preferred embodiment, the content of the polyethoxy (20) sorbitol monostearate surfactant is about 1.0% by weight based on the total weight of the polymerizable composition.

In a preferred embodiment, the hydrophilic monomer is selected from the group consisting of hydroxyethyl methacrylate (HEMA), methacrylic acid (MAA), acrylic acid, vinyl alcohol, N-vinylpyrrolidone (NVP), methyl Glyceryl acrylate (GMA), diacetone acrylamide (DAA), N,N'-dimethyl acrylamide (DMA), 2-methacryloxyethyl phosphatidylcholine (MPC), N, N'-diethylacrylamide, N-isoacrylamide, N-acrylamide morpholine, methacrylamide, silicone (for example, methacryloxypropyl tris(trimethylsiloxy) Alkyl) silane), polyols, isocyanates, their derivatives, and their combinations. In a more preferred embodiment, the hydrophilic monomer includes hydroxyethyl methacrylate (HEMA) and 2-methacryloxyethyl phosphatidylcholine (MPC).

In a preferred embodiment, the hydrophilic solvent is selected from the group consisting of polyethylene glycol, glycerin, and combinations thereof. In a more preferred embodiment, the hydrophilic solvent contains 100% by weight of polyethylene glycol based on its total weight. In a more preferred embodiment, the number average molecular weight of the polyethylene glycol is between 100 g/mole and 800 g/mole.

In a preferred embodiment, the ultraviolet light absorber is selected from the group consisting of benzotriazole ultraviolet light absorbers and benzophenone ultraviolet light absorbers.

According to a second aspect of the present invention, there is provided a method for making cosmetic lenses, including the following steps: A female mold and a male mold are provided, wherein the female mold has a concave surface, and the male mold has a convex surface corresponding to the concave surface, and when the female mold and the male mold are combined, a mold for forming the beauty is defined The cavity of the makeup lens; Distributing hydrophobic ink in the master mold to form a pattern; Injecting the aforementioned polymerizable composition between the female mold and the male mold; Pressing the female mold and the male mold so that the polymerizable composition is solidified and formed in the cavity; and It is demoulded and hydrated to make the beauty lens.

In a preferred embodiment, the method further comprises injecting the aforementioned polymerizable composition into the master mold before the step of disposing the hydrophobic ink, and distributing the polymerizable composition on the master mold through a spin molding process in.

Unless otherwise stated, the following terms used in the specification and the scope of the patent application have the following definitions. It should be noted that the indefinite article "a" or "a" used in the specification of this case and the scope of the patent application is intended to mean one or more than one, such as "at least one", "at least two" or "at least three" , And does not just refer to a single one. In addition, the terms "including", "including" and "having" used in the scope of patent application are open-ended terms and do not exclude unmentioned elements. Unless otherwise stated, the term "or" generally encompasses "and/or." The term "about" used throughout the specification and the scope of the patent application is used to describe and represent minor changes that will not substantially affect the essence of the present invention.

The invention relates to a wet injection molding process for cosmetic lenses and a polymerizable composition suitable for the process.

In the description of this case, the term "beauty lens" means a soft contact lens that is mounted on the surface of the eyeball to change the color of the eye. It is usually arranged with a color pattern on the position of the lens relative to the iris of the eye to change the iris of the wearer's eye s color. Optionally, the beauty lens may also have functions such as vision correction, ophthalmological diagnosis, drug delivery, wound healing and the like. The beauty lens is made of hydrogel. The term "hydrogel" here refers to a polymer material polymerized by hydrophilic monomers, which can absorb at least 10% by weight of water after being completely hydrated. Preferably, the water content after hydration is 30% by weight or more, more preferably, the water content after hydration is 50% by weight or more, for example, the water content after hydration is about 55% to about 58% by weight. Generally speaking, the higher the water content, the higher the oxygen permeability, and the water content of daily disposable contact lenses is usually above 50% by weight. Typical hydrophilic monomers suitable for forming water glues include but are not limited to hydroxyethyl methacrylate (HEMA), methacrylic acid (MAA), acrylic acid, vinyl alcohol, N-vinylpyrrolidone (NVP), glyceryl methacrylate (GMA), diacetone acrylamide (DAA), N,N'-dimethyl acrylamide (DMA), 2-methacryloyloxy ethyl phosphorylcholine (2-methacryloyloxy ethyl phosphorylcholine; MPC) , N,N'-diethyl acrylamide, N-isoacrylamide, N-acrylamide morpholine, methacrylamide, silicone (such as methacryloxypropyl three (trimethyl) (Siloxyalkyl) silane), polyols, isocyanates, their derivatives, and combinations of them. In a preferred embodiment, the contact lens is made of hydroxyethyl methacrylate (HEMA) monomer, N-vinylpyrrolidone (NVP) monomer, or a homopolymer of methacrylic acid (MAA) monomer Or made of copolymer, for example, made of a copolymer formed by HEMA monomer and MPC monomer.

The polymerizable composition disclosed in this case is substantially in a fluid form, and includes: about 60 to 70% by weight of a hydrophilic monomer suitable for making contact lenses; substantially higher than 0.5% by weight and less than 2.0% by weight of polyethylene Oxy (20) sorbitol monostearate surfactant (Tween ^® 60); about 0.5-2% by weight of the initiator; about 0.5-1% by weight of the cross-linking agent; and the rest are hydrophilic Solvent replenishment.

The initiator used in the present invention can be any reagent that is suitable for promoting the polymerization reaction of hydrophilic monomers to form a hydrogel, especially the initiators customarily used to make soft contact lenses. They can be roughly divided into thermal initiators. Starter or photoinitiator. Typical thermal initiators include, but are not limited to, azobisisoheptanonitrile (ADVN), 2,2'-azobisisobutyronitrile (AIBN), 2,2'-azobis(2,4-bis Methyl)valeronitrile, 2,2'-azobis(2-methyl)propionitrile, 2,2'-azobis(2-methyl)butyronitrile, diisopropyl peroxydicarbonate , Laurel peroxide, and benzyl peroxide. Typical photoinitiators include but are not limited to phenylbis(2,4,6-trimethylbenzyl) phosphine oxide (trade name Irgacure ^® 819), benzoin methyl ether, 2-hydroxy-2-methyl Phenylpropan-1-one, 1-hydroxycyclohexanone, ethyl 2,4,6-trimethylbenzylphenylphosphonate, and 2,2-diethoxyacetophenone.

The crosslinking agent used in the present invention can be any agent that has at least two polymerizable groups capable of reacting with the functional groups of the hydrogel polymer and is therefore suitable for bridging the hydrogel polymer. Crosslinking agents suitable for making soft contact lenses are well known to those with ordinary knowledge in the relevant technical field. Typical examples include but are not limited to ethylene glycol dimethacrylate (EGDMA), trimethylolpropane triacrylic acid Esters (TMPTA), tetraethylene glycol dimethacrylate (TEGDMA), triethylene glycol dimethacrylate (TrEGDMA), polyethylene glycol dimethacrylate, trimethylpropane trimethacrylate , Vinyl methacrylate, ethylene diamine dimethyl acrylamide, glyceryl dimethacrylate, triallyl isocyanurate, triallyl cyanurate, and combinations thereof.

The term "hydrophilic solvent" used in this case refers to a solvent that is miscible with water for dispersing other components in the polymerizable composition. In a preferred embodiment, the "hydrophilic solvent" is selected from the group consisting of polyethylene glycol, glycerin, and combinations thereof. The term "polyethylene glycol" or "PEG" used in this case means a polymer of ethylene oxide, which has the chemical formula H(OCH ₂ CH ₂ ) _n OH and the number average molecular weight (Mn) is between Between 100 g/mole and 800 g/mole, such as PEG 200, PEG 400 and PEG 600, especially PEG 200. The polyethylene glycol can also be partially chemically modified, such as being capped with a methoxy group to have the chemical formula CH ₃ (OCH ₂ CH ₂ ) _n OH (mPEG for short), and the hydroxyl group at the other end can also be combined with other The functional group may be substituted by other functional groups. In a more preferred embodiment, the solvent contains 100% by weight of polyethylene glycol based on its total weight, that is, the solvent is entirely composed of polyethylene glycol. In another more preferred embodiment, in addition to polyethylene glycol, the solvent may also contain up to 25% by weight of glycerin based on its total weight.

其中w + x + y + z = 20。The term "Tween" used in this case is a trademark owned by ICI Americas Inc., sometimes transliterated as "Tween", meaning non-ionic derived from polyethoxylated sorbitan esters Sexual surfactant. Examples of Tween ^® based surfactants include Tween ^® 20 (polyethoxy (20) sorbitol monolaurate), Tween ^® 40 (polyethoxy (20) sorbitol monopalmitate), Tween ^® 60 (Polyethoxy (20) sorbitol monostearate), Tween ^® 80 (polyethoxy sorbitol monooleate), etc., in which the number "20" immediately after "polyethoxy" Represents the total number of ethoxy groups-(CH ₂ CH _{2 O)-in the molecule.} As described later, the purpose of the present invention can be achieved by adding Tween ^® 60, which has the following chemical structure:

Where w + x + y + z = 20.

According to the present invention, the polymerizable composition may contain substantially more than 0.5% by weight and less than 2.0% by weight of Tween ^® 60 surfactant based on its total weight, preferably based on the total weight of the polymerizable composition. The benchmark contains about 1.0% by weight of Tween ^® 60 surfactant.

。 在另一個具體例中，所述紫外光吸收劑包含一個二苯酮類紫外光吸收劑，例如2-(4-苯甲醯基-3-羥基苯氧基)丙烯酸乙酯 （商品名Cyasorb^® UV-416，可購自於奧瑞奇化學公司），其具有如下結構：

；或是 2,2′,4,4′-四羥基二苯酮，其具有如下結構：

。In a preferred embodiment, the polymerizable composition of the present case further contains about 0.8~1.2% by weight of ultraviolet light absorber to protect the wearer’s eyes from the cornea, conjunctiva, retina and lens caused by sunlight. damage. The ultraviolet light absorber used in the present invention can be any ultraviolet light absorber suitable for soft contact lenses, which covers the ultraviolet light A (UVA) that can effectively absorb the wavelength between 315-380nm and the wavelength between 280-315nm Ultraviolet B (UVB) compounds and compositions. In some specific examples, the ultraviolet light absorber can even absorb ultraviolet light C (UVC) with a wavelength between 200 and 280 nm. Non-limiting examples of the ultraviolet light absorber include benzotriazoles, benzophenones, triazines, such as benzotriazoles (BTA), 2-[3- (2H-benzotriazol-2-yl)-4-hydroxyphenyl]ethyl 2-methacrylate (2-[3-(2 H -benzotriazol-2-yl)-4-hydroxyphenyl]ethyl methacrylate ), 2-(2'-hydroxy-5'-methacrylamidophenyl)-5-chlorobenzotriazole, 2-(2'-hydroxy-5'-methacrylamidophenyl) -5-methoxybenzotriazole, 2-(2'-hydroxy-5'-methacryloxypropyl-3'-tertiary butyl-phenyl)-5-chlorobenzotriazole, 2-hydroxy-benzophenone (2-hydroxy-benzophenone), 2,2′,4,4′-tetrahydroxybenzophenone (2,2′,4,4′-tetrahydroxybenzophenone), 2-(4-benzene 2-(4-benzoyl-3-hydroxyphenoxy)ethyl acrylate (2-(4-benzoyl-3-hydroxyphenoxy)ethyl acrylate), 4-methacryloxy-2-hydroxyphenoxy -2-hydroxybenzophenone) and so on. In a preferred embodiment, the ultraviolet light absorber includes a benzotriazole ultraviolet light absorber, such as 2-[3-(2H-benzotriazol-2-yl)-4-hydroxybenzene Yl]ethyl 2-methacrylate (trade name RUVA-93, available from Otsuka Chemical Co., Ltd.), which has the following structure:

. In another specific example, the ultraviolet light absorber includes a benzophenone ultraviolet light absorber, such as 2-(4-benzyl-3-hydroxyphenoxy) ethyl acrylate (trade name Cyasorb ^® UV-416, available from Orich Chemical Company), which has the following structure:

; Or 2,2',4,4'-tetrahydroxybenzophenone, which has the following structure:

.

The wet injection molding method used in the present invention is substantially the same as the wet injection molding method commonly used in the industry in terms of implementation steps. As shown in Figure 2, the wet injection molding method used to make beauty lenses in this case includes the following steps:

Step S01: Provide a female mold and a male mold. The female mold has a concave surface, and the male mold has a convex surface corresponding to the concave surface. When the female mold and the male mold are combined, they define a cavity for forming the contact lens.

Step S02: Grind and mix the pigment, hydrophobic resin, optional dispersant and solvent to obtain a hydrophobic ink, and then coat the hydrophobic ink on a patterned steel plate, and then transfer (pad printing) to On the surface of the master model.

Step S03: Inject the polymerizable composition into the female mold, and combine the male mold with the female mold.

Step S04: Properly heat or irradiate ultraviolet light, so that the polymerizable composition is cured into a lens in the cavity defined by the female mold and the male mold.

Step S05: Separate the male mold from the female mold, and immerse the lens attached to the male mold or the female mold in an aqueous solution (such as water, physiological saline or other aqueous buffers) to release the lens and hydrate it. The beauty lens is made.

In this case, a specific surfactant is added to the polymerizable composition without substantially changing the types and amounts of the initiator, crosslinking agent, and hydrophilic monomer in the polymerizable composition used to make cosmetic lenses. In this way, the influence of the surfactant in the polymerizable composition on the production yield is evaluated. Example 1 below shows that among the Tween ^® surfactants, only Tween ^® 60 helps maintain the structural integrity of the lens. Example 2 further shows that only the Tween ^® 60 surfactant is added in a specific ratio range, that is, based on the total weight of the polymerizable composition, substantially more than 0.5% by weight and less than 2.0% by weight of Tween ^® 60 interface is added. The active agent, preferably adding about 1.0% by weight of Tween ^® 60 surfactant, can prevent the lens from fogging while maintaining the structural integrity of the lens. In contrast, as shown in Comparative Example 1, if you add a chemical structure similar, but not with respect Span ^® ethoxy based surfactant, enhancing the manufacturing yield no benefit from the lens.

Although we do not wish to be bound by any theory, we speculate that Tween ^® surfactants have different alkyl chain lengths in their molecules, and thus exhibit different hydrophobic properties. Tween ^® 60 is more suitable for reconciling hydrophilicity. The interface between the monomer and the hydrophobic ink can effectively reduce the difference between hydrophilicity and hydrophobicity, improve the compatibility between the two, complete the crosslinking structure between the monomers, and maintain the lens shape. However, it is worth noting that the hydrophilic-lipophilic balance (HLB) commonly used in the evaluation of surfactants cannot successfully predict ^{the applicability of Tween ®} surfactants in making beauty lenses. In detail, Tween ^® 20 has an HLB value of 16.7, Tween ^® 60 has an HLB value of 14.9, and Tween ^® 80 has an HLB value of 15.0. There is almost no difference in HLB value between ^{Tween ®} 60 and Tween ^{® 80, but Example 1 shows} Only Tween ^® 60 can improve the compatibility between the hydrophilic component and the hydrophobic component in the polymerizable composition, thereby maintaining the integrity of the lens structure.

The polymerizable composition disclosed in this case is suitable for use with hydrophobic inks to make cosmetic lenses. The hydrophobic ink may include a pigment and a hydrophobic resin. Preferably, the hydrophobic ink uses an acrylic resin as the main matrix, supplemented by a small amount of pigment. The hydrophobic ink may optionally contain a dispersant and/or solvent to disperse the pigment in the hydrophobic resin, adjust the viscosity of the ink, or improve the operability of printing. The pigment is in compliance with the specifications set by the US Food and Drug Administration (FDA), including but not limited to: carbazole violet, phthalocyanine green, titanium oxide, and chromium oxide Cobalt aluminum (chromium-cobalt-aluminum oxide), chromium oxide green (chromium oxide green), iron oxide, phthalocyaninato (II) copper, red pigment 245 (pigment red 245), CI pigment violet 23, CI pigment Blue 36, CI Solvent Blue 101, CI Reduction Orange 1, CI Reduction Brown 1, CI Reduction Yellow 3, CI Reduction Blue 6, CI Reduction Green 1, CI Solvent Yellow 18, CI Reduction Orange 5, etc. The aforementioned pigments can be used alone or in combination.

The present invention also contemplates a method for making cosmetic lenses, in which in addition to the aforementioned steps S01 to S05, a spinning molding process is performed before step S02. The rotational molding process includes injecting the polymerizable composition of the present invention into a rotating mold with a master mold, and using centrifugal force when the rotating mold rotates to distribute the polymerizable composition into an outer layer in the master mold. Then, follow the aforementioned steps S02 to S05 to perform the wet injection molding process. The structural characteristics of the beauty lens produced by this method have been described in the Republic of China Patent Publication No. M557366 owned by the applicant. It has a sandwich structure, that is, the pigment layer of the lens is sandwiched in the present case to polymerize the composition. Between the outer layer and the inner layer of the solidified material, the pigment layer is not exposed and does not contact the eyeball or eyelid of the wearer, achieving the effect of not fading.

The following examples are only used to illustrate the present invention, but not to limit the scope of the present invention.

Example 1: Adding Tween ^® surfactants to prepare cosmetic contact lenses

Prepare a polymerizable composition, which contains about 60 to 70% by weight composed of hydroxyethyl methacrylate (HEMA) and 2-methacryloyloxy ethyl phosphorylcholine (MPC) Hydrophilic monomer mixture, about 0.5 to 2% by weight of Irgacure ^® 819 (purchased from BASF, Germany), about 0.5 to 1% by weight of ethylene glycol dimethacrylate (EGDMA, purchased from Mitsubishi Chemical Corporation) ), 0.4~2.0% by weight of RUVA-93 (purchased from Otsuka Chemical Co., Ltd.), 0~2.0% by weight of Tween ^® surfactant (purchased from Croda Singapore Pte Ltd), and the rest is polyethylene glycol (Average molecular weight 200 g/mol; purchased from PanReac AppliChem) to make up, and then mix it evenly.

The conventional wet injection molding process is used to prepare the lens. First use the transfer process to print the ink on the surface of the contact lens mold, where the ink contains about 10-20% by weight of carbon powder, about 10-20% by weight of iron oxide, and about 10-20% by weight of red pigment 245 ( pigment red 245; 4-((5-(Aminomethyl)-2-methoxyphenyl)azo)-3-hydroxy-N-phenylnaphthalene-2-carboxamide) and about 40~70 Acrylic resin in wt%. Subsequently, the above-mentioned polymerizable composition is injected into a contact lens mold, cured by heating or photoreaction, and then demolded by hydration, and the solvent and unreacted monomer are removed at the same time to make a finished product. Finally, the condition of the lens was checked, and the results are shown in Table 1 below.

Table 1-Lens Test Results Surfactant types Surfactant content Ink Test Results no 0% black Damaged lens Tween ^® 20 2% black Damaged lens Tween ^® 60 2% black Lens fogging Tween ^® 80 2% black Damaged lens

Table 1 shows that when no surfactant is added to the polymerizable composition, the prepared lens is damaged after hydration, as shown in FIG. 3A. After research and judgment, the possible reason is that the highly hydrophilic monomers cannot effectively penetrate into the inside of the transferred ink, resulting in incomplete cross-linking reaction, thereby affecting the lens structure. On the other hand, when a Tween ^® surfactant is added to the polymerizable composition, the lens made by adding Tween ^® 20 and Tween ^® 80 will still be damaged after hydration. In contrast, the lenses made by adding Tween 60 have relatively good lens properties, but it is also accompanied by the problem of lens fogging.

Example 2: Adding Tween ^® 60 surfactant to prepare cosmetic contact lenses

Example 1 was repeated, but 0.5% by weight, 1.0% by weight or 2.0% by weight of Tween ^® 60 surfactant (Croda Singapore Pte Ltd) was added to the polymerizable composition based on its total weight. Then, the above-mentioned ink is copied on the surface of the contact lens mold by the transfer process, and then the conventional wet injection molding process is used to prepare the lens. Finally, the condition of the lens was checked, and the results are shown in Table 2 below.

Table 2-Lens Test Results Surfactant types Surfactant content Ink Test Results Tween ^® 60 0.5% black Damaged lens Tween ^® 60 1.0% black Lens passed inspection Tween ^® 60 2.0% black Lens fogging

Table 2 shows that when ^{the addition amount of Tween ®} 60 in the polymerizable composition is 0.5% by weight, the prepared lens is prone to breakage. When ^{the addition amount of Tween ®} 60 in the polymerizable composition was increased to 2.0% by weight, fogging occurred in the prepared lens, which was consistent with the result obtained in Example 1. When ^{the addition amount of Tween ®} 60 is 1.0% by weight, the lens structure can be maintained without causing lens fogging, as shown in Figure 3B.

Comparative Example 1: Adding Span ^® surfactants to prepare cosmetic contact lenses

Repeat Example 1, but the polymerizable composition according to its total weight, 2.0% by weight of Span ^® surfactant-based reference (purchased from Croda Singapore Pte Ltd) instead of Tween ^® based surfactant. The Span ^® series surfactant is a nonionic surfactant derived from sorbitan esters. Span ^® is a trademark owned by ICI Americas Inc. ^{The Span ®} surfactants used in this example include Span ^® 80 (sorbitan monooleate), Span ^® 83 (sorbitan sesquioleate) and Span ^® 120 (sorbitan) Isostearate). Then, the above-mentioned ink is copied on the surface of the contact lens mold by the transfer process, and then the conventional wet injection molding process is used to prepare the lens. Finally, the condition of the lens was checked, and the results are shown in Table 3 below.

Table 3-Lens Test Results Surfactant types Surfactant content Ink Test Results Span ^® 80 2% black Damaged lens Span ^® 83 2% black Damaged lens Span ^® 120 2% black Damaged lens

In this embodiment, no matter which Span ^® -based surfactant is added to the polymerizable composition, the prepared lens is prone to breakage. It is speculated that the main reason is that ^{the chemical structure of Span ®} surfactants all have a considerable proportion of highly hydrophobic parts (HLB value is less than 10), so that the ink-monomer interface cannot be effectively balanced, resulting in hydrophilicity. The repulsion between the monomer and the hydrophobic ink will affect the cross-linking reaction of the monomer and cause damage to the lens.

The above embodiments are only for the purpose of illustrating the present invention, and are not intended to limit the present invention. For those with ordinary knowledge in the relevant field, various alterations or changes made without departing from the technical scope of the present invention shall also belong to the protection category of the present invention. .

10: Optical zone 11: Pattern area S01~S05: steps

Figure 1 is a schematic diagram of conventional cosmetic lenses;

Figure 2 is a flow chart of the wet injection molding method used to make beauty lenses in this case; and

Figure 3A is an image of the prepared lens that is damaged after hydration without adding a surfactant in the polymerizable composition, and Figure 3B is an image of about 1.0% by weight of Tween ^® 60 surfactant added to the polymerizable composition Under the conditions, the image of the prepared lens after hydration.

Claims (10)

A polymerizable composition for making cosmetic lenses, comprising: about 60-70% by weight of hydrophilic monomers suitable for making contact lenses; substantially higher than 0.5% by weight and less than 2.0% by weight of polyethylene oxide Base (20) sorbitol monostearate surfactant (Tween ^® 60); about 0.5-2% by weight of the initiator; about 0.5-1% by weight of the cross-linking agent; and the rest is supplemented by a hydrophilic solvent . The polymerizable composition according to claim 1, wherein the content of the polyethoxy (20) sorbitol monostearate surfactant is about 1.0% by weight based on the total weight of the polymerizable composition. The polymerizable composition according to claim 2, wherein the hydrophilic monomer is selected from the group consisting of hydroxyethyl methacrylate (HEMA), methacrylic acid (MAA), acrylic acid, vinyl alcohol, N-vinylpyrrolidone (NVP ), glycerol methacrylate (GMA), diacetone acrylamide (DAA), N,N'-dimethyl acrylamide (DMA), 2-methacrylic acid ethyl phosphatidylcholine (MPC ), N,N'-diethylacrylamide, N-isoacrylamide, N-acrylamide morpholine, methacrylamide, silicone (for example, methacryloxypropyl three (three Methylsiloxyalkyl) silane), polyols, isocyanates, their derivatives, and their combinations. The polymerizable composition according to claim 3, wherein the hydrophilic monomer comprises hydroxyethyl methacrylate (HEMA) and 2-methacryloxyethyl phosphatidylcholine (MPC). The polymerizable composition according to claim 2, wherein the hydrophilic solvent is selected from the group consisting of polyethylene glycol, glycerin, and combinations thereof. The polymerizable composition according to claim 5, wherein the hydrophilic solvent contains 100% by weight of polyethylene glycol based on its total weight. The polymerizable composition according to claim 6, wherein the number average molecular weight of the polyethylene glycol is between 100 g/mole and 800 g/mole. The polymerizable composition according to claim 1, further comprising an ultraviolet light absorber selected from the group consisting of benzotriazole ultraviolet light absorbers and benzophenone ultraviolet light absorbers. A method for making cosmetic lenses, which includes the following steps: A female mold and a male mold are provided, wherein the female mold has a concave surface, and the male mold has a convex surface corresponding to the concave surface, and when the female mold and the male mold are combined, a mold for forming the beauty is defined The cavity of the makeup lens; Distributing hydrophobic ink in the master mold to form a pattern; Inject the polymerizable composition according to any one of claims 1 to 8 between the female mold and the male mold; Pressing the female mold and the male mold so that the polymerizable composition is solidified and formed in the cavity; and It is demoulded and hydrated to make the beauty lens. The method according to claim 9, which further comprises the following steps before the step of disposing the hydrophobic ink: The polymerizable composition according to any one of claims 1 to 8 is injected into the master mold, and the polymerizable composition is distributed in the master mold through a spin molding process.

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