JPH0812341B2 - Soft contact lens manufacturing method - Google Patents

Description

TECHNICAL FIELD The present invention relates to a method for manufacturing a soft contact lens.
More specifically, it is non-hydrous and can be mechanically processed,
The present invention relates to a method for manufacturing a soft contact lens having excellent oxygen permeability.

[Prior Art] Contact lenses include hard contact lenses made of a hard material and soft contact lenses made of a soft material, but soft contact lenses are superior in terms of wearing comfort.

Many soft contact lenses are known that consist of a hydrogel containing a large amount of water in order to enhance oxygen permeability, but this contact lens contains water, so bacteria, mold, etc. It is easy to occur and needs to be disinfected by boiling every day.

On the other hand, as a soft contact lens made of a non-water-containing material that is free from the possibility of generation of bacteria and mold, those made of silicone rubber or polyalkyl acrylate are known.

It has been reported that a soft contact lens made of silicone rubber has a high oxygen permeability, but its surface is extremely water-repellent, which causes serious damage to the eye.

In addition, since contact lens materials made of polyalkyl acrylate are generally difficult to mechanically process, acrylic acid is polymerized and cured, and then mechanically processed, and then alkylated by an esterification reaction. It is known that a soft contact lens can be obtained. (See Japanese Examined Patent Publication No. 53-31189). However, the alkyl acrylate-based material obtained in this manner has a problem that sufficient oxygen permeability cannot be imparted.

[Problems to be Solved by the Invention] In view of such circumstances, an object of the present invention is to provide a method for producing a soft contact lens which is substantially non-hydrated, easy to mechanically process, and excellent in oxygen permeability. To do.

[Means for Solving Problems] The present invention provides a compound represented by the general formula (I): (In the formula, m is 1 or an integer of 3 to 5 and n is an integer of 1 to 3) A polymer having a unit represented by the formula is molded into a contact lens, and the obtained molded product is subjected to hydrosilylation reaction. The present invention relates to a method for manufacturing a soft contact lens, which is characterized in that

[Example] General formula (I): (In the formula, m is 1 or an integer of 3 to 5 and n is an integer of 1 to 3), the polymer having a unit in which a vinyl group is directly bonded to a silicon atom is a polymer in which a vinyl group is directly bonded to a silicon atom. It may be a homopolymer of bonded monomers, but since it is possible to impart shape stability and hydrophilicity by making it a copolymer, a monomer in which a vinyl group is directly bonded to a silicon atom is combined with another monomer. A copolymer obtained by copolymerization is preferable.

As a monomer to be copolymerized with a monomer in which a vinyl group is directly bonded to a silicon atom, a monomer having a polymerizable group that can be easily polymerized, rich in mechanical workability of the copolymer, moderately hard,
Methacrylic monomers that are not brittle are also preferred.

In the above copolymer, the compounding ratio (weight ratio) of the monomer in which a vinyl group is directly bonded to a silicon atom and the methacrylic monomer is preferably 100: 0 to 20:80, particularly 70:30 to 30:70. When the compounding ratio of the monomer in which the vinyl group is directly bonded to the silicon atom is less than 20:80, the oxygen permeability of the obtained soft contact lens tends to be low.

Examples of the monomer that can be used in the present invention include general formula (V): (In the formula, m is 1 or an integer of 3 to 5, n is an integer of 1 to 3) 1-methacryloyloxypropyl-5-vinyl-1,1,3,3,5,5-hexa Methyltrisiloxane, 1-methacryloyloxymethyl-5-vinyl-1,1,3,3,5,5-hexamethyltrisiloxane, 1-methacryloyloxypentyl-3-vinyl-1,1,3,3-
Tetramethyldisiloxane, etc .; Formula (VI): 1-methacryloyloxypropyl-3-
Vinyl-1,1,3,3-tetramethyldisiloxane (hereinafter V
SMA).

When VSMA is used as the monomer, the polymer obtained has the formula (II): It has a unit represented by.

Examples of the monomer copolymerized with the monomer include:
Alkyl methacrylate such as methyl methacrylate (hereinafter referred to as MMA), lauryl methacrylate (hereinafter referred to as LMA), n-butyl methacrylate (hereinafter referred to as nBuMA); trifluoroethyl methacrylate (hereinafter referred to as 3FE), hexafluoroisopropyl methacrylate, etc. Examples thereof include fluoroalkyl methacrylate.

In addition, in order to stabilize the contact lens standard, ethylene glycol dimethacrylate (hereinafter referred to as EDMA
And a cross-linking agent such as allyl methacrylate. The blending amount thereof is preferably 0.01 to 2.0 parts by weight based on 100 parts by weight of the total amount of the monomer and the monomer copolymerized with the monomer.

After mixing these monomers, polymerization is carried out. The polymerization form is generally bulk polymerization.

Examples of the polymerization catalyst for initiating the polymerization include radical polymerization catalysts such as azobisisobutyronitrile, azobisdimethylvaleronitrile (hereinafter referred to as V-65), and benzoyl peroxide. The blending amount thereof is preferably 0.001 to 1.0 part by weight based on 100 parts by weight of the total amount of the monomer and the monomer copolymerized with the monomer.

The polymerization temperature varies depending on the polymerization catalyst used, but is 30 to
The temperature is about 150 ° C., and it is possible to accelerate the polymerization while gradually raising the temperature. Further, if necessary, after the completion of the polymerization, it is possible to reheat the material to about 90 to 110 ° C. before processing to remove the strain of the material.

The polymerization time is about 2 to 48 hours, but if the polymerization is not completed, the polymerization time can be further extended.
Polymerization in a short time of less than 2 hours is not preferable because the polymer foams.

The hydrosilylation reaction proceeds by heating hydrosilane in a suitable solvent in the presence of a catalyst.

Examples of hydrosilanes used in the present invention include 1,1,
3,3-tetramethyl-1-hexyldisiloxane (hereinafter referred to as HS-2), 1,1,3,3-tetramethyl-1-methoxyethoxyethoxyethoxypropyldisiloxane (hereinafter referred to as HS-1), 1,1,3,3-tetramethyl-1
-Octyldisiloxane, 1,1,3,3-tetramethyl-1
-Decyldisiloxane, 1,1,3,3-tetramethyl-1-
General formula (III) such as methoxyethoxyethoxypropyldisiloxane: (In the formula, X is an alkyl group having 4 to 12 carbon atoms or CH _{2 3}
Examples thereof include compounds represented by OCH ₂ CH ₂ O _p CH ₃ (in the formula, p represents an integer of 1 to 4). In order to improve the hydrophilicity of the polymer, hydrosilane having an ether bond such as HS-1 is preferable, and in order to improve the mechanical strength of the polymer, alkylhydrosilane such as HS-2 is preferable. Further, in order to improve hydrophilicity, hydrosilane having an ether bond may be reacted as described above, and for example, the compound represented by the formula (IV): (Where Y is (In the formula, q represents an integer of 1 to 4), trimethylsiloxyethoxyethoxypropyl-1,1,
A method of reacting a hydrosilane such as 3,3-tetramethyldisiloxane and then detrimethylsilylating it to restore a hydroxyl group to improve hydrophilicity may be used.

When a non-polar solvent such as cyclohexane, hexane, xylene, or toluene is used as the solvent, the contact lens-shaped molded product is likely to swell, and hydrosilane dissolved in the solvent penetrates into the molded product, resulting in hydrosilylation. It is preferable because the chemical reaction is completed quickly. Among these, cyclohexane having a boiling point suitable for the hydrosilylation reaction is particularly preferable.

Examples of the catalyst include peroxides such as benzoyl peroxide and ditertiary butyl peroxide, and platinum catalysts such as chloroplatinic acid. However, chloroplatinic acid is preferable because peroxide accompanies decomposition of siloxane bonds. .

When the reaction temperature is lower than 60 ° C, the reaction does not proceed, and when it is higher than 120 ° C, a side reaction may occur. It is preferably 75 to 85 ° C. The reaction time is about 5
24 hours. Next, the present invention will be described in more detail based on examples, but the present invention is not limited to these examples.

Production Example 1 (Synthesis of VSMA) 1,3-Bis (chloropropyl) -1,1,3,3-in a 2 colored flask equipped with a stirrer, condenser and thermometer.
Tetramethyldisiloxane 0.6 mol (172.2 g), methacrylic acid 1.4 mol (206.4 g), triethylamine 1.3 mol (242.
4 g), DMF (dimethylformamide) 540 g, hydroquinone 3 g and N, N'-di-2-naphthel-p-phenylenediamine 3 g were added, and the mixture was reacted at 130 ° C for 6 hours.
From this, triethylamine hydrochloride was removed by suction. The precipitated triethylamine hydrochloride was washed with n-hexane several times and mixed with the filtrate. 700 ml of water was added to the mixed solution, and 50 g of sodium carbonate was further added. N-
Hexane (500 ml) was added to extract the product. This extraction was repeated twice more, the n-hexane layer was dried over anhydrous magnesium sulfate, and decolorized with activated carbon. The solvent was evaporated to complete removal to give 1,3-bis (methacryloyloxypropyl) -1,1,3,3-tetramethyldisiloxane.

Next, in a 500 ml Erlenmeyer flask, 1,3-bisvinyl-1,
1,3,3-Tetramethyldisiloxane 74.4g (0.4mol) and 1,
3-bis (methacryloyloxypropyl) -1,1,3,3-
154.4 g (0.4 mol) of tetramethyldisiloxane was added, and 4 g of concentrated sulfuric acid was added thereto. The mixture was stirred at room temperature for 24 hours with a magnetic stirrer. Gas chromatographic analysis of this reaction liquid confirmed that equilibrium was reached. After that, 800 ml of n-hexane was added to the reaction solution to give 10 ml of 700 ml.
% Aqueous sodium carbonate solution and 700 ml of water, and dried over anhydrous magnesium sulfate. Then, n-hexane was removed by evaporation, and vacuum distillation was performed to obtain 79-81 ° C / 0.15m
The mHg fraction was collected and VSMA was obtained.

Production Example 2 (Synthesis of HS-1) 450 g of anhydrous ethyl ether and 11.5 g of thinly-diluted sodium metal were placed in a two-necked flask equipped with a cooling tube and a dropping funnel. About 82 g (0.5 mol) of triethylene glycol monomethyl ether was added to this.
It was added dropwise over time. Furthermore, this as it is
It was left for 48 hours to dissolve the metallic sodium.

Next, 38.3 g (0.5 mol) of allyl chloride was added thereto with stirring over 1 hour. Further, it was heated to the reflux temperature and reacted for 4 hours. The reaction solution was aspirated to separate the produced salt, and the solution was distilled to 89-90 ° C /
A 1.0 mmHg fraction was collected to obtain triethylene glycol allyl methyl ether.

Next, in a 300 ml four-necked flask equipped with a condenser, a thermometer, a dropping funnel and a stirrer, 134 g (1.0 mol) of tetramethyldisiloxane and 5 g of a solution of 1 g of chloroplatinic acid dissolved in 30 ml of isopropanol (about 0.2 ml) under reduced pressure,
And the one in which isopropanol was removed by heating. To this, 96 g (0.5 mol) of triethylene glycol methylallyl ether was added dropwise at 50 ° C. over 1 hour.
After the dropping was completed, the reaction was carried out at the reflux temperature for 4 hours. The reaction solution was distilled under reduced pressure, and a fraction of 115 ° C./0.3 mmHg was collected to obtain HS-1.

Production Example 3 (Synthesis of HS-2) 126 g of 1-hexene (1.5 mol) in a 500 ml four-necked flask equipped with a cooling tube, a thermometer, a dropping funnel and a stirrer.
l) was added and heated to 50 ° C. Add 3 g of chloroplatinic acid
5 drops of a solution dissolved in 0 ml of isopropanol (about 0.2 ml)
The product obtained by removing isopropanol by heating under reduced pressure was mixed with cyclohexane (10 ml) and added. To this, 201 g (1.5 mol) of tetramethyldisiloxane was added dropwise over 2 hours. The reaction solution was distilled as it was, and a fraction of 76 to 77 ° C / 7 mmHg was collected to obtain HS-2.

Example 1 40 parts by weight of VSMA, 20 parts by weight of MMA, 40 parts by weight of nBuMA and 0.5 part by weight of EDMA shown in Table 1 were placed in a glass test tube,
Further, 0.1 part by weight of V-65 was added as a polymerization catalyst, and polymerization was carried out for 48 hours in a constant temperature water bath at 40 ° C. After that,
Polymerization was completed by heating in a circulation dryer (Chuo Rikaki Co., Ltd.) at 50 ° C for 6 hours, 60 ° C, 70 ° C, 80 ° C, 90 ° C, 100 ° C, 110 ° C for 1.5 hours each. It was

The obtained rod-shaped polymer was taken out of the glass test tube, heated in a circulating dryer at 90 ° C for 2 hours, and then cut, and a sample with a diameter of 11 to 12 mm and a thickness of about 0.2 mm was sampled. I got a film.

The obtained sample film was put into a perforated case made of Teflon, and put into a wide-necked Erlenmeyer flask together with the Teflon case. 40g of cyclohexane and 1g of chloroplatinic acid
5 drops (about 0.2m
l) and HS-1 (10 g) were added, and the mixture was heated under reflux at 88 ° C for about 15 hours. After completion of the hydrosilylation reaction, the sample film was taken out of the case, washed three times with 100 ml of ethanol, and then boiled in 400 ml of ethanol for 5 hours. After that, it was further dried overnight in a dryer at 60 ° C. The weight of the sample film was measured before and after the hydrosilylation reaction to determine the reaction rate of hydrosilane on the sample film.

With respect to the sample film subjected to the hydrosilylation reaction, the oxygen permeability coefficient, the punching load, the elongation rate and the thickness were measured and the appearance was visually inspected.

The oxygen permeability coefficient was measured using a Seikaken film oxygen permeability meter (manufactured by Rika Seiki Kogyo Co., Ltd.) at a measurement temperature of 35 ° C, and the punching load was measured using an Instron type compression tester. A 1 / 16-inch diameter pressing needle (indenter) is applied to the center of the film to measure the load at break at room temperature, and the elongation is the radius of the sample sandwiched by the O-rings before measurement.
d ₁ and d ₂ is the length from the center of the sample to the O-ring just before the sample breaks. Was used (see JP-A-63-37312). The measurement results are shown in Table 1.

Examples 2 to 17 Sample films were obtained in the same manner as in Example 1 except that the kinds and blending ratios of the monomers were changed as shown in Table 1.

Then, the reaction rate of hydrosilane was determined in the same manner as in Example 1, and similarly, the oxygen permeability coefficient, the punching load, the elongation rate and the thickness were measured, and the appearance was visually inspected.
The results are shown in Table 1.

Comparative Examples 1 to 3 Instead of VSMA, 1- (γ-methacryloyloxypropyl-α, α, γ, γ-tetramethyldisiloxanyl) -2- (γ′-methoxyethoxyethoxyethoxypropyl-α ′, α ', γ', γ'-tetramethyldisiloxanyl) ethane (hereinafter referred to as SSM)
A sample was obtained in the same manner as in Example 1 except that the hydrosilylation reaction using 1 was not performed.

That is, in Examples 1 to 17, the hydrosilylation reaction was performed after polymerizing the monomer, and in Comparative Examples 1 to 3,
The monomer was hydrosilylated and then polymerized.
Then, in the same manner as in Example 1, the oxygen permeability coefficient, the punching load, the elongation and the thickness were measured, and the appearance was visually inspected. The results are shown in Table 1.

[Effects of the Invention] According to the method for manufacturing a soft contact lens of the present invention,
A soft contact lens that can be easily mechanically processed and has higher oxygen permeability than conventional soft contact lenses can be obtained. Furthermore, since the soft contact lens obtained by the manufacturing method of the present invention is non-hydrous, it has an effect of eliminating the drawback that the lens is contaminated by the inorganic and organic substances in the tear fluid.

Further, since the soft contact lens obtained by the production method of the present invention has hydrophilicity, it solves the problem of water repellency that is found in lenses made of silicone rubber.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Jun Mizushima 5 Tohibikijima-cho, Nishi-ku, Nagoya-shi, Aichi Toyo Contact Lens Co., Ltd. (56) References JP-A-54-81363 (JP, A) JP-A-SHO 57-164153 (JP, A) JP-A-58-58519 (JP, A) JP-A-59-185310 (JP, A)

Claims (3)

[Claims] 1. General formula (I): (In the formula, m is 1 or an integer of 3 to 5 and n is an integer of 1 to 3) A polymer having a unit represented by the formula is molded into a contact lens, and the obtained molded product is subjected to hydrosilylation reaction. A method for manufacturing a soft contact lens, which is characterized in that 2. The polymer has the formula (II): The method for producing a soft contact lens according to claim 1, which has a unit represented by: 3. The molded product has the general formula (III): (In the formula, X is an alkyl group having 4 to 12 carbon atoms or CH _{2 3}
The soft contact lens according to claim 1, wherein the compound represented by OCH ₂ CH ₂ O _p CH ₃ (wherein p represents an integer of 1 to 4) is added to carry out the hydrosilylation reaction. Manufacturing method.