TW202417227A - Contact lens and silicone hydrogel contact lens - Google Patents

Abstract

A contact lens containing at least one silicon-containing monomer is provided. When the contact lens is subjected to Soxhlet extraction using methanol as an extraction solvent, a percentage by weight of the extracted hydrophilic leachables compared to the weight of the contact lens is 1.0% ~8.0%. A silicone hydrogel contact lens is also provided.

Description

Contact Lenses and Silicone Hydrogel Contact Lenses

The present invention relates to a contact lens, in particular to a silicone hydrogel contact lens.

Soft contact lenses were introduced in the 1960s. The soft material solved the discomfort of wearing hard contact lenses (RGP lenses). Users who were not used to hard contact lenses could switch to soft contact lenses. Therefore, soft contact lenses have become the main choice for contact lens users today.

However, the materials traditionally used in soft contact lenses (mainly HEMA, commonly known as hydrogel products) have low oxygen permeability, with a general Dk (oxygen permeability) of only 8~20. This causes consumers (or users; contact lens users) to often experience bloodshot eyes and corresponding discomfort due to lack of oxygen at the end of a day (wearing for more than 10 hours). Therefore, the main research and development of contact lens materials has shifted to seeking high oxygen permeable materials. Around 2000, soft contact lens products containing silicone components began to appear on the market, commonly known as silicone hydrogel contact lenses, with oxygen permeability generally above 40~50, such as Johnson & Johnson's Acuvue Advanced product. After 2010, due to economic development and consumers' better health awareness, daily disposable soft contact lenses began to be accepted by the market. Daily disposable products have significant advantages over long-term monthly or even annual disposable products: there is no need to remove and clean the lenses every day, which can avoid eye injuries caused by lens damage during cleaning, and can also avoid bacterial infections caused by incomplete cleaning, resulting in serious complications such as keratitis and conjunctivitis.

The main technical threshold of silicone hydrogel contact lenses is how to make the lens sufficiently hydrophilic to avoid discomfort caused by the hydrophobicity of the silicone component. The industry generally uses the contact angle to judge the hydrophilicity of the lens surface. The industry first developed plasma technology to treat the lens surface to reduce the contact angle of the lens surface. However, this technology requires complicated processing procedures, the lens production cost is high, and it is difficult to sell the product as a daily disposable product. A more successful solution to further overcome the hydrophilicity of the silicone hydrogel surface is to add polyvinylpyrrolidone (PVP) as an internal wetting agent in the formula. This method avoids the complex process of plasma surface treatment. However, due to the compatibility problem between PVP and silicone hydrogel formula, it is necessary to select specific silicon-containing ingredients as a match in practice. At the same time, it is also necessary to add a large amount of specific organic solvents to help maintain the stability of the formula to avoid precipitation of PVP or silicon-containing ingredients in the formula. In addition to the above two technologies, researchers have also developed a formulation technology that does not require plasma surface treatment and does not require the addition of PVP as an internal wetting agent. However, the disadvantage of this type of formulation technology is that it requires specific silicon-containing components and specific hydrophilic monomers to achieve the desired lens properties, and it needs to be matched with a more hydrophilic mold material instead of polypropylene (PP) to produce contact lenses. Therefore, it is necessary to further establish a set of contact lens technology that can meet consumer needs, is suitable for long-term wear, and is easy to mass-produce.

The present invention provides a contact lens which is suitable for consumers to wear for a long time and is convenient for mass production.

The present invention also provides a silicone hydrogel contact lens that is suitable for consumers to wear for a long time and is easy to mass produce.

To achieve the above advantages, an embodiment of the present invention provides a contact lens containing at least one silicon-containing monomer, and the contact lens is subjected to Soxhlet extraction using methanol as an extraction solvent, and the weight percentage of the extracted hydrophilic filterable substance compared to the weight of the contact lens is 1.0%~8.0%.

To achieve the above advantages, another embodiment of the present invention provides a silicone hydrogel contact lens, comprising a first silicon-containing monomer, a second silicon-containing monomer, a first hydrophilic monomer, a second hydrophilic monomer and a silicon-containing crosslinking agent.

The first silicon-containing monomer has the following structure: Where A is the following structure: or the following structure: ; wherein R ₁ is H or CH ₃ or OSi(CH ₃ ) ₃ , R ₂ is H or CH ₃ or OSi(CH ₃ ) ₃ , and L ₁ is the following structure or a combination thereof: Among them, n1 is 1~5, m1 is 1~4, m2 is 0~1, m3 is 1~4, m4 is 0~1, m5 is 1~4, and m6 is 1~4.

The second silicon-containing monomer comprises the first structure or the second structure; The first structure: wherein a is 0-20; R ₃ is H or CH ₃ or C ₂ H ₅ , R ₄ is H or CH ₃ or OSi(CH ₃ ) ₃ , R ₅ is H or CH ₃ or OSi(CH ₃ ) ₃ , and L ₂ is the following structure or a combination thereof: Among them, n6 is 1~5, n7 is 1~5, m7 is 1~4, m8 is 0~1, m9 is 1~4, m10 is 0~1, m11 is 1~4, m12 is 1~4, m13 is 0~1, m14 is 1~4, and m15 is 1~4; The second structure mentioned above: wherein c is 0-20; wherein R ₁₀ is H or CH ₃ or C ₂ H ₅ , R ₁₁ is H or CH ₃ or OSi(CH ₃ ) ₃ , R ₁₂ is H or CH ₃ or OSi(CH ₃ ) ₃ , L ₅ is the following structure or a combination thereof: O or NH; L ₆ is the following structure or a combination thereof: Among them, n20 is 1~5, m34 is 1~4, m35 is 0~1, m36 is 1~4, m37 is 0~1, m38 is 1~4, and m39 is 1~4.

The first hydrophilic monomer contains an N-vinyl group. In addition, the second hydrophilic monomer is different from the first hydrophilic monomer.

The silicone hydrogel contact lens is subjected to Soxhlet extraction using methanol as an extraction solvent, and the weight percentage of the extracted hydrophilic filterable matter compared to the weight of the silicone hydrogel contact lens is 1.0% to 8.0%.

Since the present invention adopts the above-mentioned components and proportions to manufacture, the contact lenses and silicone hydrogel contact lenses manufactured have the advantages of good hydrophilicity and are suitable for consumers to wear for a long time.

In order to make the above and other purposes, features and advantages of the present invention more clearly understood, the following is a detailed description of the embodiments with reference to the accompanying drawings.

One embodiment of the present invention provides a contact lens containing at least one silicon-containing monomer, and the contact lens is subjected to a Soxhlet extraction using methanol as an extraction solvent, and the weight percentage of the extracted hydrophilic filterable substance compared to the weight of the contact lens is 1.0% to 8.0%. Specifically, the contact lens is, for example, a silicone hydrogel contact lens, and includes a first silicon-containing monomer, a second silicon-containing monomer, a first hydrophilic monomer, a second hydrophilic monomer, and a silicon-containing crosslinking agent.

The first silicon-containing monomer has the following structure: Where A is the following structure: or the following structure: ; wherein R ₁ is H or CH ₃ or OSi(CH ₃ ) ₃ , R ₂ is H or CH ₃ or OSi(CH ₃ ) ₃ , and L ₁ is the following structure or a combination thereof: Among them, n1 is 1~5, m1 is 1~4, m2 is 0~1, m3 is 1~4, m4 is 0~1, m5 is 1~4, and m6 is 1~4.

The second silicon-containing monomer has the following first structure or second structure: First structure: wherein a is 0-20; R ₃ is H or CH ₃ or C ₂ H ₅ , R ₄ is H or CH ₃ or OSi(CH ₃ ) ₃ , R ₅ is H or CH ₃ or OSi(CH ₃ ) ₃ , and L ₂ is the following structure or a combination thereof: Among them, n6 is 1~5, n7 is 1~5, m7 is 1~4, m8 is 0~1, m9 is 1~4, m10 is 0~1, m11 is 1~4, m12 is 1~4, m13 is 0~1, m14 is 1~4, and m15 is 1~4; The second structure: wherein c is 0-20; wherein R ₁₀ is H or CH ₃ or C ₂ H ₅ , R ₁₁ is H or CH ₃ or OSi(CH ₃ ) ₃ , R ₁₂ is H or CH ₃ or OSi(CH ₃ ) ₃ , L ₅ is the following structure or a combination thereof: O or NH; L ₆ is the following structure or a combination thereof: Among them, n20 is 1~5, m34 is 1~4, m35 is 0~1, m36 is 1~4, m37 is 0~1, m38 is 1~4, and m39 is 1~4;

The first hydrophilic monomer contains an N-vinyl group. The second hydrophilic monomer is different from the first hydrophilic monomer.

Silicone hydrogel contact lenses were subjected to Soxhlet extraction using methanol as the extraction solvent. The weight percentage of the extracted hydrophilic filterable matter compared to the weight of the silicone hydrogel contact lenses was 1.0%~8.0%.

In this article, the lens is also called a contact lens. In addition, the lens formulation (referred to as formulation) in this article refers to a formulation composed of a monomer, a crosslinking agent and an initiator, and other ingredients such as fillers are added in addition to the formulation. Fillers will be described in detail below. "Monomer" is used to refer to the lens formulation that can be polymerized through free radical polymerization during the curing process to further form a polymer. The monomer generally has a double bond that can accept free radicals in its chemical structure.

"Silicone monomer" refers to a monomer having at least one siloxane bond (-Si-O-) chemical structure. Examples of the silicon-containing monomers that can be used in this embodiment include: 3-[Tris(trimethylsiloxy)silyl]propyl methacrylate (TRIS); and monomethacryloxypropyl terminated polydimethylsiloxane (MPDMS). The CAS No. of the commonly used monomethacryloxypropyl terminated polydimethylsiloxane is 146632-07-7. Other silicon-containing monomers that can be used in this embodiment include, but are not limited to: 2-(Trimethylsilyloxy)ethyl methacrylate (2-(Trimethylsilyloxy)ethyl methacrylate), (3-(3-Methacryloxy-2-hydroxypropoxy)propylbis(trimethylsiloxy)methylsilane (SiGMA), (Methacryloxymethyl)bis(trimethylsiloxy)methylsilane, Methacryloxymethylphenethyltris(trimethylsiloxy)silane alkyl (Methacryloxymethylphenethyltris(trimethylsiloxy)silane), O-(methacryloxyethyl)-3-[bis(trimethylsiloxy)methylsilyl]propylcarbamate, 3-[Tris(trimethylsiloxy)silyl]propylvinylcarbamate vinyl carbamate). The above silicon-containing monomers can be purchased from suppliers such as Sigma-Aldrich, Gelest, JNC, Shin-Etsu, Pharnocia, Bimax, etc. The silicon-containing monomers that can be used in this embodiment are also exemplified by: mono-(3-methacryloxy-2-hydroxypropyloxy)propyl terminated, mono-butyl terminated polydimethylsiloxane ((mono-(3-methacryloxy-2-hydroxypropyloxy)propyl terminated, mono-butyl terminated polydimethylsiloxane)), which can be synthesized by referring to the method in U.S. Patent US20030162862A1. The silicon-containing monomers that can be used in this embodiment are also exemplified by: polydimethylsiloxane terminated by unilateral monocarbinol (monoCarbinol terminated polydimethylsiloxane; CAS No: 207308-30-3, abbreviated as MOHPMDS) and urethane ester with 2-isocyanatoethyl methacrylate (IEM); the synthesis reaction of the urethane ester can use 1,8-diazabicyclo[5.4.0]undec-7-ene (DBU) as a catalyst.

In this embodiment, the first silicon-containing monomer includes, for example, at least one of methacryloxypropyl tris(trimethylsiloxy)silane, (3-(3-methacryloxy-2-hydroxypropoxy)propyl bis(trimethylsiloxy)methyl silane, O-(methacryloxyethyl)-3-[bis(trimethylsiloxy)methylsilyl]propyl carbamate, and 3-[tris(trimethylsiloxy)silyl]propyl vinyl carbamate.

The second silicon-containing monomer includes, for example, at least one of monomethacryloxypropyl terminated polydimethylsiloxane, monomethacryloxypropyl terminated urethane polydimethylsiloxane, and mono-(3-methacryloxy-2-hydroxypropoxy)propyl terminated monobutyl terminated polydimethylsiloxane. In addition, the molecular weight of the second silicon-containing monomer may be 350 to 2500, preferably 500 to 1500.

The total content of the first silicon-containing monomer and the second silicon-containing monomer is, for example, 15% to 60% of the weight of the silicone hydrogel contact lens after deducting the filler, preferably 25% to 45%.

"Hydrophilic monomer" refers to a monomer that has a hydrophilic chemical structure. The hydrophilic monomers that can be used in the present embodiment include, but are not limited to, N-vinyl pyrrolidone (NVP), N-methyl-N-vinylacetamide (MVA), N,N-dimethyl acrylamide (DMA), N,N-diethylacrylamide, N-(Hydroxymethyl)acrylamide, N-hydroxyethylacrylamide, 2-Hydroxyethyl methacrylate (HEMA), ethylene glycol vinyl ether (EGVE), 1,4-butanediol vinyl ether (1,4-butanediol vinyl ether), and the like. ether, referred to as BVE), di(ethylene glycol) vinyl ether, hydroxypropyl methacrylate (Hydroxypropyl methacrylate and/or Hydroxyisopropyl methacrylate), 2-methyl-2-acrylate-2-hydroxybutyl ester (Hydroxybutyl methacrylate, referred to as HOBMA), poly(propylene ethylene glycol) methacrylate, poly(ethpropylene glycol) acrylate, glyceryl methacrylate, 2-hydroxyethyl acrylate, hydroxypropyl acrylate and/or Hydroxyisopropyl acrylate, 4-hydroxybutyl acrylate acrylate), Glyceryl acrylate, N-[Tris(hydroxymethyl)methyl]acrylamide, Methacrylamide, 2-Hydroxypropyl methacrylamide, N-Isopropylacrylamide, N,N-Diethylacrylamide, N-Ethylacrylamide, and 2-Methacryloyloxyethyl phosphorylcholine. In this embodiment, the preferred hydrophilic monomer is N-vinylpyrrolidone. A more preferred choice is a combination of N-vinylpyrrolidone (NVP) and hydroxyethyl methacrylate (HEMA). The above hydrophilic monomers can generally be purchased from suppliers such as Sigma-Aldrich, TCI, Alfa Aesar, etc.

In this embodiment, the first hydrophilic monomer containing an N-vinyl group is, for example, N-vinyl pyrrolidone. In addition, the content of the N-vinyl pyrrolidone is, for example, more than 40% of the weight of the silicone hydrogel contact lens after deducting the filler.

In this embodiment, the second hydrophilic monomer includes at least one of hydroxyethyl methacrylate, ethylene glycol vinyl ether, and 1,4-butanediol vinyl ether.

"UV Blocker" refers to a component added to a lens to block UV wavelength light. UV blockers generally used in contact lenses also have a double bond that can accept free radicals in their chemical structure, so they also belong to the category of monomers. UV blockers that can be used in this embodiment include but are not limited to: 2-[3-(2H-Benzotriazol-2-yl)-4-hydroxyphenyl]ethyl methacrylate (HMEPB), 2-(4-Benzoyl-3-hydroxyphenoxy)ethyl acrylate. The above-mentioned UV blocking agents can generally be purchased from suppliers such as Sigma-Aldrich, TCI, Alfa Aesar, etc.

In this embodiment, the contact lens may further include at least one non-silicon-containing cross-linking agent.

"Crosslinking agent" refers to a substance that can cause monomers to undergo crosslinking reactions during polymerization, and can provide the polymer produced by the polymerization reaction with the required crosslinking density, so that two polymer chains react and bond to form a network polymer. Crosslinking agents can be divided into non-silicon-containing crosslinking agents and silicon-containing crosslinking agents according to whether they have a chemical structure of silicon-oxygen bonding (-Si-O-). The non-silicon-containing crosslinking agent that can be used in the present embodiment includes but is not limited to: ethylene glycol dimethacrylate (EGDMA), diethylene glycol dimethacrylate (Di(ethylene glycol) dimethacrylate), triethylene glycol dimethacrylate (Triethylene glycol dimethacrylate), tetraethylene glycol dimethacrylate (TEGDMA), ethylene glycol diacrylate (Ethylene glycol diacrylate), diethylene glycol diacrylate (Di(ethylene glycol) diacrylate), triethylene glycol diacrylate, tetraethylene glycol diacrylate (TEGDMA), diacrylate), N,N'-Methylenebis(acrylamide), N,N'-Ethylenebis(acrylamide), N,N'-(1,2-Dihydroxyethylene)bisacrylamide, Trimethylolpropanetrimethacrylate (TEPTMA), N,N'-Hexamethylenebis(methacrylamide), Glycerol trimethacrylate, Polyethylene glycol dimethacrylate, Polyethylene glycol dimethacrylate diacrylate), (Z)-2-butenedioic acid-2-[(2-methyl-1-oxo-2-propenyl)oxy]ethyl monoester (mono-2-(Methacryloyloxy)ethyl maleate), diurethanedimethacrylate, 3-isopropyl-dimethylbenzyl isocyanate (3-Isopropenyl-α,α-dimethylbenzylisocyanate), etc. The above non-silicon-containing crosslinking agents can generally be purchased from suppliers such as Sigma-Aldrich, TCI, Alfa Aesar, etc.

In this embodiment, the at least one non-silicon-containing crosslinking agent includes, for example, at least one of ethylene glycol dimethacrylate, triethylene glycol dimethacrylate, tetraethylene glycol dimethacrylate, and trihydroxymethylpropane trimethacrylate.

"Silicone crosslinking agent" refers to a crosslinking agent that has at least one siloxane bond chemical structure (-Si-O-). The silicone crosslinking agent that can be used in this embodiment includes but is not limited to the following examples. For example: methacryloxypropyl terminated polydimethylsiloxane (DMPDMS for short). The CAS No. of commonly used methacryloxypropyl terminated polydimethylsiloxane is 58130-03-3. Another example is polyethylene glycol functionalized methacryloxypropyl terminated polydimethylsiloxane, such as the following structure:

The silicon-containing crosslinking agent can be used in combination with other crosslinking agents to form appropriate lens properties. In this embodiment, the silicon-containing crosslinking agent can be used to adjust the hydrophilic filterable material and the hydrophobic filterable material of the lens. The above silicon-containing crosslinking agent can be purchased from suppliers such as Sigma-Aldrich, Gelest, JNC, Shin-Etsu, Pharnocia, Bimax, etc. The silicon-containing crosslinking agent that can be used in this embodiment is also 1,3-bis[4-vinyloxycarbonyloxy)butyl]tetramethyldisiloxane, which can be synthesized by referring to the method in US Patent US5070215A. The silicon-containing crosslinking agent that can be used in the present embodiment is also bis-3-Methacryloxy-2-hydroxypropyloxypropyl polydimethylsiloxane, which can be synthesized by referring to the method in U.S. Patent US20030162862A1, and the crosslinking agent can be obtained by replacing mono-(2,3-epoxy)propylether terminated polydimethylsiloxane with epoxypropoxypropyl terminated polydimethylsiloxane. The silicon-containing crosslinking agent that can be used in this embodiment is also, for example, a urethane ester of carbinol (hydroxyl) terminated polydimethylsiloxane (DOHPDMS; CAS No: 156327-07-0) and 2-isocyanatoethyl methacrylate (IEM); the synthesis reaction of the urethane ester can use 1,8-diazabicyclo[5.4.0]undec-7-ene (DBU) as a catalyst.

In one embodiment of the present invention, the silicon-containing crosslinking agent comprises, for example, the following structure: wherein b is 0-20; R ₆ is H or CH ₃ or C ₂ H ₅ , R ₇ is H or CH ₃ or OSi(CH ₃ ) ₃ , and L ₃ is the following structure or a combination thereof: wherein n12 is 1 to 5, n13 is 1 to 5, m16 is 1 to 4, m17 is 0 to 1, m18 is 1 to 4, m19 is 0 to 1, m20 is 1 to 4, m21 is 1 to 4, m22 is 0 to 1, m23 is 1 to 4, and m24 is 1 to 4; R ₈ is the following structure or a combination thereof: Wherein R ₉ is H or CH ₃ or C ₂ H ₅ , L ₄ is the following structure or a combination thereof: Among them, n18 is 1~5, n19 is 1~5, m25 is 1~4, m26 is 0~1, m27 is 1~4, m28 is 0~1, m29 is 1~4, m30 is 1~4, m31 is 0~1, m32 is 1~4, and m33 is 1~4.

In one embodiment of the present invention, the silicon-containing crosslinking agent comprises, for example, the following structure: wherein d is 0-20; R ₁₃ is H or CH ₃ or C ₂ H ₅ , R ₁₄ is H or CH ₃ or C ₂ H ₅ , L ₇ is the following structure or a combination thereof: O or NH; L ₈ is the following structure or a combination thereof: wherein n25 is 1 to 5, m40 is 1 to 4, m41 is 0 to 1, m42 is 1 to 4, m43 is 0 to 1, m44 is 1 to 4, and m45 is 1 to 4; R ₁₅ is the following structure or a combination thereof: Wherein R ₁₆ is H or CH ₃ or C ₂ H ₅ , L ₉ is the following structure or a combination thereof: Among them, n31 is 1~5, m46 is 1~4, m47 is 0~1, m48 is 1~4, m49 is 0~1, m50 is 1~4, and m51 is 1~4.

In one embodiment of the present invention, the silicon-containing crosslinking agent includes, for example, at least one of methacryloxypropyl-terminated polydimethylsiloxane, methacryloxypropyl-terminated urethane polydimethylsiloxane, methacryloxypropyl-terminated polydimethylsiloxane modified with polyethylene glycol, 1,3-bis[4-vinyloxycarbonyloxy)butyl]tetramethyldisiloxane, and bis-3-methacryloxy-2-hydroxypropoxypropyl polydimethylsiloxane.

The molecular weight of the silicon-containing crosslinking agent is, for example, below 3000, preferably below 1500, for example, below 800.

The content of the silicon-containing crosslinking agent is, for example, 0.1% to 6.0% of the weight of the silicone hydrogel contact lens after deducting the filler, and preferably 0.1% to 3.0%.

"Initiators" act to generate free radicals required for free radical chain reactions. Generally, they can be divided into thermal initiators and photoinitiators according to the different ways in which they can be activated to generate free radicals. Initiators that can be activated by heat to generate free radicals are called thermal initiators, and initiators that can be activated by light to generate free radicals are called photoinitiators. The photoinitiator that can be used in this embodiment includes but is not limited to: Irgacure® 1173 (2-Hydroxy-2-methylpropiophenone), phenylbis(2,4,6-trimethylbenzoyl)phosphine oxide (Phenylbis(2,4,6-trimethylbenzoyl)phosphine oxide, referred to as 819), and in other embodiments, for example, (2,4,6-trimethylbenzoyl)diphenylphosphine oxide (Diphenyl(2,4,6-trimethylbenzoyl)phosphine oxide) and benzoin bismethyl ether (2,2-Dimethoxy-2-phenylacetophenone) are used. The thermal initiator that can be used in this embodiment includes but is not limited to: azobisisobutyronitrile, 4,4'-azobis(4-cyanovaleric acid), 1,1'-azo(cyanocyclohexane) (1,1'-Azobis(cyclohexanecarbonitrile)), 2,2'-Azobis(2-methylpropionamidine)), 2,2'-Azobis(2-methylpropionamidine)dihydrochloride), 2,2'-Azobis[2-(2-imidazolin-2-yl)propane]dihydrochloride hydrochloride), 2,2'-Azobis{2-[1-(2-hydroxyethyl)-2-imidazolin-2-yl]propane}dihydrochloride), 2,2'-Azobis(1-imino-1-pyrrolidino-2-ethylpropane)dihydrochloride), 2,2'-Azobis{2-[1-(2-hydroxyethyl)-2-imidazolin-2-yl]propane}dihydrochloride [1,1-bis(hydroxymethyl)-2-hydroxyethyl]propionamide} (2,2'-Azobis{2-methyl-N-[1,1-bis(hydroxymethyl)-2-hydroxyethyl]propionamide}), 2,2'-Azo(2-methyl-N-(2-hydroxyethyl)propionamide) (2,2'-Azobis[2-methyl-N-(2-hydroxyethyl)propionamide]), 2,2'-Azobis(4-methoxy-2,.4-dimethyl valeronitrile)), Benzoyl peroxide, etc. The above-mentioned initiators can generally be purchased from suppliers such as Sigma-Aldrich, TCI, Alfa Aesar, etc.

"Diluent" refers to an additional component added to the lens formulation that does not have a double bond that can accept free radicals to produce free radical polymerization, and therefore cannot polymerize with monomers or crosslinking agents or initiators to further form polymers. Some fillers may also have the function of chain transfer agents and involve a portion of the free radical chain reaction process, but their chain transfer effect is generally far lower than that of true chain transfer agents such as thiol. Therefore, the function of fillers as chain transfer agents is not considered in this embodiment. Fillers are usually used to help the compatibility of components in lens formulations. Solvent compounds may be a choice of fillers. The filler that can be used in the present embodiment includes but is not limited to: alcohols such as ethanol, isopropyl alcohol (IPA), n-butanol, n-hexanol, and tert-Amyl alcohol; esters such as ethyl acetate, butyl acetate, and ethyl lacetate; organic acids such as oleic acid; alcohol ethers such as ethyl cellosolve, 2-propoxyethanol, ethylene glycol monobutyl ether, hexyl cellosolve, ethylene glycol monophenyl ether, propylene glycol monomethyl ether, propylene glycol phenyl ether, and propylene glycol phenyl ether. ether), diethylene glycol methyl ether (2-(2-methoxyethoxy)ethanol), diethylene glycol ethyl ether (2-(2-ethoxyethoxy)ethanol), diethylene glycol monobutyl ether (diethylene glycol hexyl ether), dipropylene glycol monomethyl ether (dipropylene glycol monomethyl ether), dipropylene glycol propyl ether (dipropylene glycol propyl ether), dipropylene glycol n-butyl ether. The above fillers can generally be purchased from suppliers such as Sigma-Aldrich, TCI, Alfa Aesar, etc.

The following implementation samples are used to produce finished lenses according to the following process. First, a specific ratio of monomers, crosslinking agents and initiators are quantitatively mixed into a lens formula (or simply referred to as a formula), and a filler of a specific weight percentage compared to the total weight of the formula is mixed with the formula and stirred under nitrogen conditions to ensure that the ingredients in the formula can be completely mixed and uniform (hereinafter, the formula mixed with the filler is referred to as the mixed formula). After the mixed formula is uniformly mixed, the mixed formula is injected into a female mold made by injection molding, and then a male mold made by injection molding is pressed with the female mold to form a formula-mold complex. The liquid mixed formula exists in the space between the male mold and the female mold, and then the formula-mold complex is subjected to a curing process. The technology of making female molds and male molds by injection molding belongs to the industry common knowledge technology.

The curing process can use heat curing or light curing. The implementation samples listed below are mainly based on light curing. The light source used for light curing can be ultraviolet light, visible light, or far infrared light. After the formula mold compound is cured, it becomes a lens formula compound. At this time, the lens in the lens formula compound is a dry lens (a lens that has not been hydrated). The lens in the lens formula compound is separated from the mold. The separation method can be mechanical force, or one of the molds (which can be a male mold or a female mold) can be separated from the dry lens first, and then the remaining part of the lens formula compound (including the dry lens and the mold part attached to it, which can be a male mold or a female mold) is immersed in a solvent (usually an aqueous solution containing a certain proportion of organic solvents). After the dry lens absorbs the liquid, it expands and becomes a wet lens and is separated from the mold. After the semi-finished lens (dry lens or wet lens) is separated from the mold, the semi-finished product can be subjected to a hydration process.

The purpose of the hydration process is to clean the unreacted monomers, crosslinking agents, initiators, fillers, and oligomers with a low degree of reaction in the semi-finished lens products to avoid excessive residues in the lens products and cause toxic reactions or irritation when users wear the finished lenses. The hydration process can be cleaned only by water or deionized water, but usually this type of hydration process has a weak cleaning ability for silicone hydrogel products and requires a longer hydration process time or a higher hydration temperature to ensure that the semi-finished lens products can be cleaned. A more commonly used hydration process is, for example, to first rapidly expand the semi-finished lens product with an aqueous solution containing a certain proportion of an organic solvent, thereby accelerating the cleaning, and finally washing the organic solvent off the semi-finished lens product with water or deionized water. Although the author has tried to avoid limiting the hydration process in the implementation samples listed below, the concentration of the organic solvent used in the hydration process, different process times, process temperatures, and the number of hydrations have an impact on the product characteristics. The most suitable hydration process must be adjusted according to the lens formula and curing process to ensure that the monomers, crosslinking agents, initiators, fillers and oligomers that should be washed away can be cleaned and left as little as possible in the finished lens. At the same time, the proportion of hydrophobic filterable substances in the finished lens is reduced and the proportion of hydrophilic filterable substances is increased.

After the hydration process, the wet lens can be placed in the buffer solution for balance first, and then placed in the PP cup containing the buffer solution, or placed directly in the PP cup containing the buffer solution for balance. After that, the PP cup is sealed with aluminum foil by heat sealing, so that the lens and the buffer solution can be isolated from the external environment, and the aluminum foil and the PP cup can be separated during the wet heat sterilization process, which will cause bacteria to grow on the finished lens. The pH value (pH) of the buffer solution is generally between 6.0 and 8.0, and the osmotic pressure is generally between 270 and 420 mOsm/kg. The buffer may be a phosphoric acid buffer or a boric acid buffer, and a polymer having a wetting effect, a surfactant or other additives may be added to the buffer as required.

In the characterization of finished lenses, the contact angle is measured using the sessile drop method. The water break-up time (WBUT) is measured by clamping the finished lens with tweezers and gently shaking it three times, timing and visually observing the time when dry spots appear on the lens surface. Experience shows that this data is positively correlated with the tear break-up time (TBUT) when the lens is actually worn on the eye. The water content measurement method is based on the method recommended in ISO18369-3. The oxygen permeability coefficient measurement method is based on the polarographic method recommended in ISO18369-4. The test method of filterable sequestrants is based on the Soxhlet extraction method recommended in ISO18369-4, but the extraction time is set to 24 hours for a more realistic evaluation of the filterable sequestrants of the lens. If hydrophilic filterable sequestrants are to be measured, a polar organic solvent can be used as the extraction solvent. In the following implementation sample, methanol is used as the extraction solvent to measure the hydrophilic filterable sequestrants. If hydrophobic filterable sequestrants are to be measured, a non-polar organic solvent can be used as the extraction solvent. In the following implementation sample, n-hexane is used as the extraction solvent to measure the hydrophobic filterable sequestrants. Soxhlet extraction uses 180 ml of solvent to extract 90 finished lenses. If methanol is used as the extraction solvent, it is equivalent to using 142.56 g of methanol to extract 90 finished lenses (methanol density 0.792 g/ml). If n-hexane is used as the extraction solvent, it is equivalent to using 117.9 g of n-hexane to extract 90 finished lenses (n-hexane density 0.655 g/ml). The filterable sequestrant calculation method for the sample implemented in this article is defined as:

When the silicone hydrogel contact lens is subjected to Soxhlet extraction using methanol as an extraction solvent, the weight percentage of the extracted hydrophilic filterable matter compared to the weight of the silicone hydrogel contact lens is, for example, 2.5% to 6.5%, preferably 3.0% to 5.0%.

When the silicone hydrogel contact lens is subjected to Soxhlet extraction using n-hexane as an extraction solvent, the weight percentage of the extracted hydrophobic filterable matter compared to the weight of the silicone hydrogel contact lens is, for example, less than 3.2%, preferably less than 2.2%, and more preferably less than 1.5%.

The contact angle of the above-mentioned silicone hydrogel contact lenses is less than or equal to 70°, and the water breaking time (WBUT) is greater than or equal to 10 seconds.

Implementation sample 1: Prepare the lens formula according to the following ratio: SiGMA 10.00%, MPDMS (molecular weight about 600~800) 15.01%, HEMA 10.01%, NVP 54.82%, EGVE 7.00%, TEGDMA 1.97%, 819 0.60%, HMEPB 0.59%, the total amount of the above is 100%, including monomers, initiators, and crosslinkers. The lens formula uses the above total amount as the denominator of the weight percentage, and then adds 10% Hexanol and 10% ethyl Acetate (hereinafter, the formula mixed with fillers is referred to as the mixed formula). Stir the mixed formula for more than 4 hours under nitrogen conditions to ensure that the mixed formula is completely mixed. The mixed formula is injected into the female mold made by injection molding, and then the male mold made by injection molding is pressed against the female mold to form a formula-mold complex. The liquid mixed formula exists in the space between the male mold and the female mold. The formula-mold complex is cured by a UV lamp with a main wavelength of 365 nm, maintaining the ambient temperature between 33°C and 38°C, and the irradiation time is 60 minutes. After the curing process, the formula-mold complex becomes a lens formula complex. At this time, the lens in the lens formula complex is a dry lens (a lens that has not been hydrated). Remove the male mold of the lens formula compound first, then soak the female mold with the dry lens in a 30% ethanol aqueous solution for more than 2 hours. After the dry lens absorbs the aqueous solution, it will naturally separate from the female mold and become a wet lens. The wet lens will continue to undergo the following hydration process in sequence: soak in a 50% ethanol aqueous solution for about 1 hour, then soak in a 75% ethanol aqueous solution for about 1 hour, then soak in a 50% ethanol aqueous solution for about 30 minutes, then soak in a 30% ethanol aqueous solution for 30 minutes, and finally wash in deionized water (DI Water) 6 times (change deionized water each time), each time for 30 minutes to avoid ethanol residue. The above ethanol concentrations all represent volume percentage concentrations. The wet lenses washed with deionized water (DI Water) were placed in a phosphate buffer solution for equilibrium, and finally placed in a PP cup of phosphate buffer solution, and heat-sealed with aluminum foil, and sterilized in a sterilizer. After sterilization, the aluminum foil was opened to obtain the finished lens. The finished lens was tested as follows, and the contact angle was 44.59 degrees (the average value of 5 finished lenses), the water breaking time (WBUT) was 20.2 seconds (the average value of 5 finished lenses), the water content was 66.53%, and the oxygen permeability coefficient Dk = 55. The finished lens was subjected to a Soxhlet extraction with methanol, and the weight difference before and after the extraction was calculated, and the weight percentage of the hydrophilic leachable compared to the weight of the silicone hydrogel contact lens was 1.7%. The finished lens was subjected to a Soxhlet extraction with n-hexane, and the weight percentage of the hydrophobic leachable compared to the weight of the silicone hydrogel contact lens was 1.5%.

Implementation sample 2: The lens formula is prepared according to the following proportions: TRIS 15.51%, MPDMS (molecular weight about 1000) 17.45%, HEMA 11.63%, NVP 54.29%, EGDMA 0.51%, 819 0.61%, the total amount of the above is 100%, including monomers, initiators, and crosslinkers. The lens formula uses the above total amount as the denominator of the weight percentage, and then 10% Hexanol and 10% ethyl acetate are additionally added. The mixed formula is stirred for more than 4 hours under nitrogen conditions to ensure that the mixed formula is completely mixed. The mixed formula is injected into a female mold made by injection molding, and then a male mold made by injection molding is pressed with the female mold to form a formula-mold complex, and the liquid mixed formula exists in the space between the male mold and the female mold. The formula mold compound is cured by UV light with a main wavelength of 365nm, maintaining the ambient temperature between 33°C and 38°C, and the irradiation time is 60 minutes. After the curing process, the formula mold compound becomes a lens formula compound, at which time the lens in the lens formula compound is a dry lens (a lens that has not been hydrated). The male mold of the lens formula compound is removed first, and then the female mold with the dry lens is immersed in a 25% IPA aqueous solution for more than 2 hours. After the dry lens absorbs the aqueous solution, it naturally separates from the female mold and becomes a wet lens. The wet lens is then subjected to the following hydration processes in sequence: immersed in a 50% IPA aqueous solution for about 1 hour, then immersed in a 75% IPA aqueous solution for about 1 hour, then immersed in a 50% IPA aqueous solution for about 30 minutes, then immersed in a 25% IPA aqueous solution for 30 minutes, and finally washed in deionized water (DI Water) 6 times (replace deionized water each time), each time for 30 minutes to avoid IPA residue. The above IPA concentrations all represent volume percentage concentrations. The wet lenses washed with deionized water (DI Water) were placed in a phosphate buffer solution for equilibrium, and finally placed in a PP cup of phosphate buffer solution, and heat-sealed with aluminum foil, and sterilized in a sterilizer. After sterilization, the aluminum foil was opened to obtain the finished lens. The finished lens was tested as follows, and the contact angle was 23.53 degrees (the average value of 5 finished lenses), the water breaking time (WBUT) was 23.4 seconds (the average value of 5 finished lenses), the water content was 69.76%, and the oxygen permeability coefficient Dk = 64. The finished lens was subjected to a Soxhlet extraction with methanol, and the weight difference before and after the extraction was calculated, and the weight percentage of the hydrophilic leachable compared to the weight of the silicone hydrogel contact lens was 2.4%. The finished lens was subjected to a Soxhlet extraction with n-hexane, and the weight percentage of the hydrophobic leachable compared to the weight of the silicone hydrogel contact lens was 1.3%.

Implementation sample 3: The lens formula is prepared according to the following ratios: TRIS 15.39%, MPDMS (molecular weight about 900) 17.32%, HEMA 11.54%, NVP 53.88%, DMPDMS (molecular weight about 380~550) 1.26%, 819 0.61%, the total amount of the above is 100%, including monomers, initiators, and crosslinkers. The lens formula uses the above total amount as the denominator of the weight percentage, and then adds 10% Hexanol and 10% ethyl acetate. The method of making the lens product with this mixed formula is the same as the method described in Implementation sample 2. The finished lens was subjected to the following tests, and the contact angle was 34.2 degrees (average value of 5 finished lenses), the water breaking time (WBUT) was 30.4 seconds (average value of 5 finished lenses), the water content was 70.00%, and the oxygen permeability coefficient Dk = 75. The finished lens was subjected to Soxhlet extraction with methanol, and the weight difference before and after extraction was calculated, and the weight percentage of the hydrophilic leachable compared to the weight of the silicone hydrogel contact lens was 2.7%. The finished lens was subjected to Soxhlet extraction with n-hexane, and the weight percentage of the hydrophobic leachable compared to the weight of the silicone hydrogel contact lens was 0.8%.

Implementation sample 4: The lens formula is prepared according to the following ratios: TRIS 15.20%, MPDMS (molecular weight about 1000) 17.10%, HEMA 11.40%, NVP 53.21%, DMPDMS (molecular weight about 900~1200) 2.49%, 819 0.60%, the total amount of the above is 100%, including monomers, initiators, and crosslinkers. The lens formula uses the above total amount as the denominator of the weight percentage, and then adds 10% Hexanol and 10% ethyl acetate. The method of making the lens product with this mixed formula is the same as the method described in Implementation sample 2. The finished lens was subjected to the following tests, and the contact angle was 46.33 degrees (average value of 5 finished lenses), the water breaking time (WBUT) was 23.6 seconds (average value of 5 finished lenses), the water content was 67.62%, and the oxygen permeability coefficient Dk = 83. The finished lens was subjected to Soxhlet extraction with methanol, and the weight difference before and after extraction was calculated, and the weight percentage of the hydrophilic leachable compared to the weight of the silicone hydrogel contact lens was 3.3%. The finished lens was subjected to Soxhlet extraction with n-hexane, and the weight percentage of the hydrophobic leachable compared to the weight of the silicone hydrogel contact lens was 1.1%.

Example 5: Using the same mixing formula as in Example 2, the hydration process in the method for making the finished lens is as follows: soaking in a 50% IPA aqueous solution for about 1 hour, then soaking in a new 50% IPA aqueous solution for about 1 hour, then soaking in a 50% IPA aqueous solution for about 30 minutes, then soaking in a 25% IPA aqueous solution, and finally washing in deionized water (DI Water) 6 times (deionized water is replaced each time), each time for 30 minutes to avoid IPA residue. The rest of the method for making the finished lens is the same as described in Example 2. The finished lens was subjected to the following tests, and the contact angle was 32.41 degrees (the average value of 5 finished lens products measured), and the water breaking time (WBUT) was 19.0 seconds (the average value of 5 finished lens products measured). The finished lens was subjected to a Soxhlet extraction with methanol, and the weight difference before and after the extraction was calculated, and the weight percentage of the hydrophilic leachable compared to the weight of the silicone hydrogel contact lens was 2.8%. The finished lens was subjected to a Soxhlet extraction with n-hexane, and the weight percentage of the hydrophobic leachable compared to the weight of the silicone hydrogel contact lens was 1.6%.

Example 6: Using the same mixing formula as in Example 3, the hydration process in the method for making the finished lens is as follows: soaking in a 50% IPA aqueous solution for about 1 hour, then soaking in a new 50% IPA aqueous solution for about 1 hour, then soaking in a 50% IPA aqueous solution for about 30 minutes, then soaking in a 25% IPA aqueous solution, and finally washing in deionized water (DI Water) 6 times (deionized water is replaced each time), each time for 30 minutes to avoid IPA residue. The rest of the method for making the finished lens is the same as described in Example 2. The finished lens was subjected to the following tests, and the contact angle was 30.22 degrees (the average value of 5 finished lens products measured), and the water breaking time (WBUT) was 27.8 seconds (the average value of 5 finished lens products measured). The finished lens was subjected to a Soxhlet extraction with methanol, and the weight difference before and after the extraction was calculated, and the weight percentage of the hydrophilic leachable compared to the weight of the silicone hydrogel contact lens was 3.2%. The finished lens was subjected to a Soxhlet extraction with n-hexane, and the weight percentage of the hydrophobic leachable compared to the weight of the silicone hydrogel contact lens was 1.0%.

Example 7: Using the same mixing formula as in Example 4, the hydration process in the method for making the finished lens is as follows: soaking in a 50% IPA aqueous solution for about 1 hour, then soaking in a new 50% IPA aqueous solution for about 1 hour, then soaking in a 50% IPA aqueous solution for about 30 minutes, then soaking in a 25% IPA aqueous solution, and finally washing in deionized water (DI Water) 6 times (deionized water is replaced each time), each time for 30 minutes to avoid IPA residue. The rest of the method for making the finished lens is the same as described in Example 2. The finished lens was subjected to the following tests, and the contact angle was 33.92 degrees (the average value of 5 finished lens products measured), and the water breaking time (WBUT) was 23.8 seconds (the average value of 5 finished lens products measured). The finished lens was subjected to a Soxhlet extraction with methanol, and the weight difference before and after the extraction was calculated, and the weight percentage of the hydrophilic leachable compared to the weight of the silicone hydrogel contact lens was 3.1%. The finished lens was subjected to a Soxhlet extraction with n-hexane, and the weight percentage of the hydrophobic leachable compared to the weight of the silicone hydrogel contact lens was 0.8%.

Implementation Sample 8: The lens formula is prepared according to the following ratio: TRIS 9.98%, MPDMS (molecular weight about 900) 15.03%, HEMA 10.01%, NVP 54.80%, BVE 6.98%, TEGDMA 1.49%, DMPDMS (molecular weight about 380~550) 0.50%, 819 0.60%, HMEPB 0.61%, the total amount of the above is 100%. The lens formula uses the above total amount as the denominator of the weight percentage, and then adds 10% Hexanol and 10% ethyl acetate. The method of making the finished lens from this mixed formula is the same as the method described in Implementation Sample 5. The finished lens was subjected to the following tests, and the contact angle was 39.75 degrees (average value of 5 finished lenses), the water breaking time (WBUT) was 34.8 seconds (average value of 5 finished lenses), the water content was 66.35%, and the oxygen permeability coefficient Dk = 69. The finished lens was subjected to Soxhlet extraction with methanol, and the weight difference before and after extraction was calculated, and the weight percentage of the hydrophilic leachable compared to the weight of the silicone hydrogel contact lens was 4.7%. The finished lens was subjected to Soxhlet extraction with n-hexane, and the weight percentage of the hydrophobic leachable compared to the weight of the silicone hydrogel contact lens was 0.6%.

Implementation Sample 9: Using the same mixing formula as in Implementation Sample 2, the hydration process in the method for producing the finished lens is as follows: soaking in deionized water for about 24 hours, and then replacing the deionized water and repeating the cleaning 6 times (replacing the deionized water each time), each time for 30 minutes. The rest of the method for producing the finished lens is the same as described in Implementation Sample 2. The finished lens was subjected to the following tests, and the contact angle was 30.89 degrees (the average value of 5 finished lens products measured), and the water breaking time (WBUT) was 24.2 seconds (the average value of 5 finished lens products measured). The finished lens was subjected to a Soxhlet extraction with methanol, and the weight difference before and after the extraction was calculated, and the weight percentage of the hydrophilic leachable compared to the weight of the silicone hydrogel contact lens was 6.7%. The finished lens was subjected to a Soxhlet extraction with n-hexane, and the weight percentage of the hydrophobic leachable compared to the weight of the silicone hydrogel contact lens was 3.1%.

Example 10: Using the same mixing formula as in Example 3, the hydration process in the method for producing the finished lens is as follows: soaking in deionized water for about 24 hours, and then replacing the deionized water and repeating the cleaning 6 times (replacing the deionized water each time), each time for 30 minutes. The rest of the method for producing the finished lens is the same as described in Example 2. The finished lens was subjected to the following tests, and the contact angle was 31.43 degrees (the average value of 5 finished lens products measured), and the water breaking time (WBUT) was 25.6 seconds (the average value of 5 finished lens products measured). The finished lens was subjected to a Soxhlet extraction with methanol, and the weight difference before and after the extraction was calculated, and the weight percentage of the hydrophilic leachable compared to the weight of the silicone hydrogel contact lens was 4.4%. The finished lens was subjected to a Soxhlet extraction with n-hexane, and the weight percentage of the hydrophobic leachable compared to the weight of the silicone hydrogel contact lens was 1.3%.

Take 70g of DOHPDMS with a molecular weight of about 2000 and dissolve it in 300ml of ethyl acetate, stir in a round-bottomed flask until completely dissolved, then equip the round-bottomed flask with a heating device and a condensing reflux device to maintain the temperature at 52°C ~59°C equilibrium, then take 5.43g of IEM and add it to the reaction (with a molar ratio of 1:1 to DOHPDMS), and add 0.2g of DBU as a catalyst. After about 20 hours of reaction, ethyl acetate is drained with a cycloconcentrator to obtain polydimethylsiloxane with both methacryloyl propyl end-capping and urethane structure, i.e. methacryloyl propyl end-capped urethane polydimethylsiloxane, abbreviated as DMUPDMS, and the molecular weight of the product is about 2300.

Take 70 g of MOHPDMS with a molecular weight of about 1000 and dissolve it in 300 ml of ethyl acetate. Stir in a round-bottom flask until it is completely dissolved. Then, equip the round-bottom flask with a heating device and a condensing reflux device to maintain the temperature at 52°C ~ 60°C. Then take 10.86 g of IEM and add it to the reaction (with a molar ratio of 1:1 to MOHPDMS), and add 0.25 g of DBU as a catalyst. After about 20 hours of reaction, ethyl acetate is drained with a cycloconcentrator to obtain polydimethylsiloxane with both unilateral methacryloylpropyl end-capping and urethane structure, namely monomethacryloylpropyl end-capped urethane polydimethylsiloxane, abbreviated as MUPDMS, and the molecular weight of the product is about 1150.

Implementation sample 11: The lens formula was prepared according to the following ratios: SiGMA 21.43%, MUPDMS 21.06%, HEMA 8.67%, NVP 42.04%, DMUPDMS 5.34%, TEPTMA 0.53%, 819 0.30%, 1173 0.63%, and the total amount of the above is 100%, including monomers, initiators, and crosslinkers. The lens formula uses the above total amount as the denominator of the weight percentage, and 10% of Hexanol and 10% of ethyl acetate are additionally added. The method of making the finished lens from this mixed formula is the same as the method described in Implementation sample 2. The finished lens was subjected to the following tests, and the contact angle was 34.43 degrees (the average value of 5 finished lens products measured) and the water breaking time (WBUT) was 18.0 seconds (the average value of 5 finished lens products measured). The finished lens was subjected to a Soxhlet extraction with methanol, and the weight difference before and after the extraction was calculated, and the weight percentage of the hydrophilic leachable compared to the weight of the silicone hydrogel contact lens was 3.6%. The finished lens was subjected to a Soxhlet extraction with n-hexane, and the weight percentage of the hydrophobic leachable compared to the weight of the silicone hydrogel contact lens was 0.9%.

Implementation sample 12: The lens formula was prepared according to the following proportions: SiGMA 20.88%, MUPDMS 17.45%, HEMA 10.22%, NVP 46.15%, DMUPDMS 3.69%, TEGDMA 0.62%, 819 0.48%, 1173 0.51%, and the total amount of the above is 100%, including monomers, initiators, and crosslinkers. The lens formula uses the above total amount as the denominator of the weight percentage, and 10% of Hexanol and 10% of ethyl acetate are additionally added. The method of making a finished lens from this mixed formula is the same as the method described in Implementation sample 2. The finished lens was subjected to the following tests, and the contact angle was 31.88 degrees (the average value of 5 finished lens products measured) and the water breaking time (WBUT) was 20.4 seconds (the average value of 5 finished lens products measured). The finished lens was subjected to a Soxhlet extraction with methanol, and the weight difference before and after the extraction was calculated, and the weight percentage of the hydrophilic leachable compared to the weight of the silicone hydrogel contact lens was 3.9%. The finished lens was subjected to a Soxhlet extraction with n-hexane, and the weight percentage of the hydrophobic leachable compared to the weight of the silicone hydrogel contact lens was 0.9%.

Implementation sample 13: The lens formula was prepared according to the following proportions: SiGMA 21.09%, MUPDMS 20.45%, HEMA 7.93%, NVP 48.52%, TEGDMA 1.04%, 819 0.46%, 1173 0.51%, and the total amount of the above is 100%, including monomers, initiators, and crosslinkers. The lens formula uses the above total amount as the denominator of the weight percentage, and additionally adds 10% Hexanol and 10% ethyl acetate. The method of making a finished lens from this mixed formula is the same as the method described in Implementation sample 2. The finished lens was subjected to the following tests, and the contact angle was 42.56 degrees (the average value of 5 finished lens products measured), and the water breaking time (WBUT) was 12.2 seconds (the average value of 5 finished lens products measured). The finished lens was subjected to a Soxhlet extraction with methanol, and the weight difference before and after the extraction was calculated, and the weight percentage of the hydrophilic leachable compared to the weight of the silicone hydrogel contact lens was 2.2%. The finished lens was subjected to a Soxhlet extraction with n-hexane, and the weight percentage of the hydrophobic leachable compared to the weight of the silicone hydrogel contact lens was 1.3%.

The finished lenses of 8 groups of implementation samples 1 to 8 were rated by 10 people. The specifications of the male and female molds of the 8 groups of lenses were pre-adjusted during the production process so that the differences in lens dimensions such as diameter, base curve, and sagittal height were within 0.2 mm. The purpose was to reduce the impact of the differences in dimensions between groups on the wearing experience. The experiment was conducted on 8 working days. On each working day, the subjects were asked to record their subjective scores, and the scores were statistically given after the end of the experiment. On each working day, the subjects also participated in the slit lamp examination (which belongs to the external score), and the tear membrane rupture time was recorded by the optometrist. The subjective ratings of wearing of the above 8 groups of sample lenses were the highest for sample 8, and the ratings of samples 2, 3, 4, 6, and 7 were similar and slightly better than samples 1 and 5. The subjective ratings of wearing were evaluated by tear break-up time (TBUT) using a slit lamp. Among them, the tear break-up time of sample 8 performed best. When the tear break-up time was measured within 10 minutes after wearing the lenses, the tear break-up time of 10 people was greater than 18 seconds; the tear break-up time of samples 1 to 7 fell between 10 and 18 seconds. When the subjects wore the glasses for more than 6 hours (the experiment was controlled between 6 and 8 hours after wearing), the tear membrane rupture time was measured for the second time. For sample 8, the tear membrane rupture time was still greater than 18 seconds for 8 subjects and between 10 and 18 seconds for 2 subjects. The tear membrane rupture time of sample 1 to 7 groups was approximately between 8 and 15 seconds.

The test results of the above implementation samples and the subsequent trial wearing comparison experiments show that whether the hydrophilic filter and the hydrophobic filter of the lens are in the appropriate range is crucial to whether the contact lens can be worn for a long time and still feel comfortable.

Since the present invention adopts the above-mentioned components and proportions to manufacture the contact lenses, the manufactured contact lenses have the advantages of good hydrophilicity and are suitable for consumers to wear for a long time.

Although the present invention has been disclosed as above by way of embodiments, they are not intended to limit the present invention. A person having ordinary knowledge in the technical field to which the present invention belongs may make some changes and modifications without departing from the spirit and scope of the present invention. Therefore, the protection scope of the present invention shall be subject to the scope defined in the attached patent application.

without

without

Claims (48)

A contact lens contains at least one silicon-containing monomer, and the contact lens is subjected to Soxhlet extraction using methanol as an extraction solvent, and the weight percentage of the extracted hydrophilic filterable substance compared to the weight of the contact lens is 1.0% to 8.0%. The contact lens as described in claim 1, wherein the silicon-containing monomer includes at least one of methacryloxypropyl tris(trimethylsiloxy)silane, (3-(3-methacryloyloxy-2-hydroxypropoxy)propyl bis(trimethylsiloxy)methyl silane, O-(methacryloyloxyethyl)-3-[bis(trimethylsiloxy)methylsilyl]propyl carbamate, and 3-[tris(trimethylsiloxy)silyl]propyl vinyl carbamate. The contact lens as claimed in claim 1, wherein the silicon-containing monomer comprises at least one of monomethacryloxypropyl-terminated polydimethylsiloxane, monomethacryloxypropyl-terminated urethane polydimethylsiloxane, and mono-(3-methacryloxy-2-hydroxypropoxy)propyl-terminated monobutyl-terminated polydimethylsiloxane. A contact lens as described in claim 1, wherein the contact lens comprises N-vinyl pyrrolidone. A contact lens as described in claim 4, wherein the contact lens further comprises a filler, and the content of N-vinyl pyrrolidone accounts for more than 40% of the weight of the contact lens after deducting the filler. The contact lens as described in claim 1 further comprises at least one silicon-containing cross-linking agent. The contact lens as described in claim 6, wherein the at least one silicon-containing crosslinking agent includes at least one of methacrylamide-terminated polydimethylsiloxane, methacrylamide-terminated urethane polydimethylsiloxane, methacrylamide-terminated polydimethylsiloxane modified with polyethylene glycol, 1,3-bis[4-vinyloxycarbonyloxy)butyl]tetramethyldisiloxane, and bis-3-methacryloxy-2-hydroxypropoxypropyl polydimethylsiloxane. The contact lens as claimed in claim 7, wherein the molecular weight of each of the at least one silicon-containing crosslinking agent is less than 3000. The contact lens as claimed in claim 7, wherein the molecular weight of each of the at least one silicon-containing crosslinking agent is less than 1500. The contact lens as claimed in claim 7, wherein the molecular weight of each of the at least one silicon-containing crosslinking agent is less than 800. The contact lens as described in claim 7, wherein the contact lens further comprises a filler, and the content of the at least one silicon-containing crosslinking agent accounts for 0.1% to 6.0% of the weight of the contact lens after deducting the filler. The contact lens as described in claim 7, wherein the contact lens further comprises a filler, and the content of the at least one silicon-containing crosslinking agent accounts for 0.1% to 3.0% of the weight of the contact lens after deducting the filler. The contact lens of claim 1, wherein the contact lens further comprises at least one non-silicon-containing cross-linking agent. The contact lens as described in claim 13, wherein the at least one non-silicon-containing crosslinking agent includes at least one of ethylene glycol dimethacrylate, triethylene glycol dimethacrylate, tetraethylene glycol dimethacrylate, and trihydroxymethylpropane trimethacrylate. A contact lens as described in claim 1, wherein the contact lens further comprises a first hydrophilic monomer, at least a second hydrophilic monomer and a filler, wherein the first hydrophilic monomer is N-vinyl pyrrolidone, and the content of N-vinyl pyrrolidone accounts for more than 40% of the weight of the contact lens after deducting the filler. The contact lens as described in claim 15, wherein the at least one second hydrophilic monomer comprises at least one of hydroxyethyl methacrylate, ethylene glycol vinyl ether, and 1,4-butanediol vinyl ether. The contact lens as claimed in claim 1, wherein when the contact lens is subjected to Soxhlet extraction using methanol as an extraction solvent, the weight percentage of the extracted hydrophilic filterable substance compared to the weight of the contact lens is 2.5% to 6.5%. The contact lens as described in claim 1, wherein when the contact lens is subjected to Soxhlet extraction using methanol as an extraction solvent, the weight percentage of the extracted hydrophilic filterable substance compared to the weight of the contact lens is 3.0% to 5.0%. A contact lens as described in claim 1, wherein when the contact lens is subjected to Soxhlet extraction using n-hexane as an extraction solvent, the weight percentage of the extracted hydrophobic filterable substance compared to the weight of the contact lens is less than 3.2%. A contact lens as described in claim 1, wherein when the contact lens is subjected to Soxhlet extraction using n-hexane as an extraction solvent, the weight percentage of the extracted hydrophobic filterable substance compared to the weight of the contact lens is less than 2.2%. A contact lens as described in claim 1, wherein when the contact lens is subjected to Soxhlet extraction using n-hexane as an extraction solvent, the weight percentage of the extracted hydrophobic filterable substance compared to the weight of the contact lens is less than 1.5%. A contact lens as claimed in claim 1, wherein the contact angle of the contact lens is less than or equal to 70° and the water breaking time (WBUT) is greater than or equal to 10 seconds. A silicone hydrogel contact lens comprises a first silicon-containing monomer, a second silicon-containing monomer, a first hydrophilic monomer, a second hydrophilic monomer, and a silicon-containing cross-linking agent, wherein: the first silicon-containing monomer comprises the following structure; Where A is the following structure: or the following structure: ; wherein R ₁ is H or CH ₃ or OSi(CH ₃ ) ₃ , R ₂ is H or CH ₃ or OSi(CH ₃ ) ₃ , and L ₁ is the following structure or a combination thereof: wherein n1 is 1-5, m1 is 1-4, m2 is 0-1, m3 is 1-4, m4 is 0-1, m5 is 1-4, and m6 is 1-4; the second silicon-containing monomer comprises a first structure or a second structure; the first structure: wherein a is 0-20; R ₃ is H or CH ₃ or C ₂ H ₅ , R ₄ is H or CH ₃ or OSi(CH ₃ ) ₃ , R ₅ is H or CH ₃ or OSi(CH ₃ ) ₃ , and L ₂ is the following structure or a combination thereof: Where n6 is 1~5, n7 is 1~5, m7 is 1~4, m8 is 0~1, m9 is 1~4, m10 is 0~1, m11 is 1~4, m12 is 1~4, m13 is 0~1, m14 is 1~4, and m15 is 1~4; The second structure: wherein c is 0-20; wherein R ₁₀ is H or CH ₃ or C ₂ H ₅ , R ₁₁ is H or CH ₃ or OSi(CH ₃ ) ₃ , R ₁₂ is H or CH ₃ or OSi(CH ₃ ) ₃ , L ₅ is the following structure or a combination thereof: O or NH; L ₆ is the following structure or a combination thereof: wherein n20 is 1-5, m34 is 1-4, m35 is 0-1, m36 is 1-4, m37 is 0-1, m38 is 1-4, and m39 is 1-4; the first hydrophilic monomer contains N-vinyl; the second hydrophilic monomer is different from the first hydrophilic monomer; the silicone hydrogel contact lens is subjected to Soxhlet extraction using methanol as an extraction solvent, and the weight percentage of the extracted hydrophilic filterable matter compared to the weight of the silicone hydrogel contact lens is 1.0%-8.0%. The silicone hydrogel contact lens as described in claim 23, wherein the first silicon-containing monomer includes at least one of methacryloxypropyl tris(trimethylsiloxy)silane, (3-(3-methacryloyloxy-2-hydroxypropoxy)propyl bis(trimethylsiloxy)methyl silane, O-(methacryloyloxyethyl)-3-[bis(trimethylsiloxy)methylsilyl]propyl carbamate, and 3-[tris(trimethylsiloxy)silyl]propyl vinyl carbamate. The silicone hydrogel contact lens as described in claim 23, wherein the second silicon-containing monomer includes at least one of monomethacryloxypropyl-terminated polydimethylsiloxane, monomethacryloxypropyl-terminated urethane polydimethylsiloxane, and mono-(3-methacryloxy-2-hydroxypropoxy)propyl-terminated monobutyl-terminated polydimethylsiloxane. The silicone hydrogel contact lens as described in claim 25, wherein the molecular weight of the second silicon-containing monomer is 350-2500. The silicone hydrogel contact lens as described in claim 25, wherein the molecular weight of the second silicon-containing monomer is 500-1500. The silicone hydrogel contact lens as described in claim 23, wherein the silicone hydrogel contact lens further comprises a filler, and the total content of the first silicon-containing monomer and the second silicon-containing monomer accounts for 15% to 60% of the weight of the silicone hydrogel contact lens after deducting the filler. The silicone hydrogel contact lens as described in claim 23, wherein the silicone hydrogel contact lens further comprises a filler, and the total content of the first silicon-containing monomer and the second silicon-containing monomer accounts for 25% to 45% of the weight of the silicone hydrogel contact lens after deducting the filler. The silicone hydrogel contact lens as described in claim 23, wherein the first hydrophilic monomer containing an N-vinyl group is N-vinyl pyrrolidone. The silicone hydrogel contact lens as described in claim 30, wherein the silicone hydrogel contact lens further comprises a filler, and the content of N-vinyl pyrrolidone accounts for more than 40% of the weight of the silicone hydrogel contact lens after deducting the filler. The silicone hydrogel contact lens as described in claim 23, wherein the second hydrophilic monomer includes at least one of hydroxyethyl methacrylate, ethylene glycol vinyl ether, and 1,4-butanediol vinyl ether. The silicone hydrogel contact lens as claimed in claim 23, wherein the silicon-containing crosslinking agent comprises the following structure: wherein b is 0-20; R ₆ is H or CH ₃ or C ₂ H ₅ , R ₇ is H or CH ₃ or OSi(CH ₃ ) ₃ , and L ₃ is the following structure or a combination thereof: wherein n12 is 1 to 5, n13 is 1 to 5, m16 is 1 to 4, m17 is 0 to 1, m18 is 1 to 4, m19 is 0 to 1, m20 is 1 to 4, m21 is 1 to 4, m22 is 0 to 1, m23 is 1 to 4, and m24 is 1 to 4; R ₈ is the following structure or a combination thereof: Wherein R ₉ is H or CH ₃ or C ₂ H ₅ , L ₄ is the following structure or a combination thereof: Among them, n18 is 1~5, n19 is 1~5, m25 is 1~4, m26 is 0~1, m27 is 1~4, m28 is 0~1, m29 is 1~4, m30 is 1~4, m31 is 0~1, m32 is 1~4, and m33 is 1~4. The silicone hydrogel contact lens as claimed in claim 23, wherein the silicon-containing crosslinking agent comprises the following structure: wherein d is 0-20; R ₁₃ is H or CH ₃ or C ₂ H ₅ , R ₁₄ is H or CH ₃ or C ₂ H ₅ , L ₇ is the following structure or a combination thereof: O or NH; L ₈ is the following structure or a combination thereof: wherein n25 is 1 to 5, m40 is 1 to 4, m41 is 0 to 1, m42 is 1 to 4, m43 is 0 to 1, m44 is 1 to 4, and m45 is 1 to 4; R ₁₅ is the following structure or a combination thereof: Wherein R ₁₆ is H or CH ₃ or C ₂ H ₅ , L ₉ is the following structure or a combination thereof: Among them, n31 is 1~5, m46 is 1~4, m47 is 0~1, m48 is 1~4, m49 is 0~1, m50 is 1~4, and m51 is 1~4. The silicone hydrogel contact lens as described in claim 23, wherein the silicon-containing crosslinking agent includes at least one of methacrylamide-terminated polydimethylsiloxane, methacrylamide-terminated urethane polydimethylsiloxane, methacrylamide-terminated polydimethylsiloxane modified with polyethylene glycol, 1,3-bis[4-vinyloxycarbonyloxy)butyl]tetramethyldisiloxane, and bis-3-methacryloyloxy-2-hydroxypropoxypropyl polydimethylsiloxane. The silicone hydrogel contact lens as claimed in claim 34, wherein the molecular weight of the silicon-containing crosslinking agent is less than 3000. The silicone hydrogel contact lens as claimed in claim 34, wherein the molecular weight of the silicon-containing crosslinking agent is less than 1500. The silicone hydrogel contact lens as claimed in claim 34, wherein the molecular weight of the silicon-containing crosslinking agent is less than 800. The silicone hydrogel contact lens as described in claim 34, wherein the silicone hydrogel contact lens further comprises a filler, and the content of the silicon-containing crosslinking agent accounts for 0.1% to 6.0% of the weight of the silicone hydrogel contact lens after deducting the filler. The silicone hydrogel contact lens as described in claim 34, wherein the silicone hydrogel contact lens further comprises a filler, and the content of the silicon-containing crosslinking agent accounts for 0.1% to 3.0% of the weight of the silicone hydrogel contact lens after deducting the filler. The silicone hydrogel contact lens as claimed in claim 23, wherein the silicone hydrogel contact lens further comprises at least one non-silicone-containing cross-linking agent. The silicone hydrogel contact lens as described in claim 41, wherein the at least one non-silicone-containing crosslinking agent includes at least one of ethylene glycol dimethacrylate, triethylene glycol dimethacrylate, tetraethylene glycol dimethacrylate, and trihydroxymethylpropane trimethacrylate. The silicone hydrogel contact lens as described in claim 23, wherein when the silicone hydrogel contact lens is subjected to Soxhlet extraction using methanol as an extraction solvent, the weight percentage of the extracted hydrophilic filterable substance compared to the weight of the silicone hydrogel contact lens is 2.5% to 6.5%. The silicone hydrogel contact lens as described in claim 23, wherein when the silicone hydrogel contact lens is subjected to Soxhlet extraction using methanol as an extraction solvent, the weight percentage of the extracted hydrophilic filterable substance compared to the weight of the silicone hydrogel contact lens is 3.0% to 5.0%. The silicone hydrogel contact lens as described in claim 23, wherein when the silicone hydrogel contact lens is subjected to a Soxhlet extraction using n-hexane as an extraction solvent, the weight percentage of the extracted hydrophobic filterable substance compared to the weight of the silicone hydrogel contact lens is less than 3.2%. The silicone hydrogel contact lens as described in claim 21, wherein when the silicone hydrogel contact lens is subjected to a Soxhlet extraction using n-hexane as an extraction solvent, the weight percentage of the extracted hydrophobic filterable substance compared to the weight of the silicone hydrogel contact lens is less than 2.2%. The silicone hydrogel contact lens as described in claim 21, wherein when the silicone hydrogel contact lens is subjected to a Soxhlet extraction using n-hexane as an extraction solvent, the weight percentage of the extracted hydrophobic filterable substance compared to the weight of the silicone hydrogel contact lens is less than 1.5%. A silicone hydrogel contact lens as described in claim 23, wherein the contact angle (Contact Angle) of the silicone hydrogel contact lens is less than or equal to 70°, and the water breaking time (WBUT) is greater than or equal to 10 seconds.