JPH04370122A - Production of contact lens - Google Patents

Abstract

PURPOSE:To obtain the subject product absolutely nontoxic due to the absence of an unreacted monomer on the lens surface and having an improved wettability of the surface by applying graft polymerization treatment to the lens surface and subsequently immersing the lens in a solvent. CONSTITUTION:A copolymer between a (meth)acrylic acid siloxy-substituted ester of formula I (R is CH3 or H; X and Y are 1-6C alkyl, cyclohexyl, etc.; R<4> is 1-6C alkyl., phenyl, etc.; m is 1-3; n is 1-5) and a (meth)acrylic acid ester selected, e.g. from <=20F (meth)acrylic acid fluoroalkyl substituted compounds of formula II (A is H, phenyl, etc.; Rf is polyfluoroalkyl or pentafluorophenyl) is initially used as the raw material of a base material for a contact lens. The surface of the base material is then subjected to electrical discharge treatment at the ordinary or reduced pressure and a hydrophilic monomer is subsequently graft polymerized on the above-treated surface. The resultant graft base material is then immersed in a solvent (preferably water of >=20 deg.C).

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a manufacturing method for obtaining hard contact lenses that permanently maintain surface wettability and are comfortable to wear.

0002

2. Description of the Related Art In order to reduce the feeling of a foreign body when wearing a contact lens and improve the feeling of wearing it, it is important to improve the compatibility between the cornea and the lens surface. A specific method is to graft-polymerize a hydrophilic monomer onto the contact lens surface to improve the wettability of the lens surface. By the way, to briefly explain the treatment process of surface graft polymerization, first, a contact lens base material that has been subjected to an electric discharge treatment or the like is immersed in a monomer solution. Next, after removing dissolved oxygen, this is heated and subjected to surface graft polymerization treatment.

0003

[Problems to be Solved by the Invention] However, in the above-mentioned conventional technology, unpolymerized monomer components remain on the surface of the lens base material, and this residual monomer causes eye irritation when wearing contact lenses and corneal irritation. clouding, conjunctival hyperemia,
The problem was that in the worst case, it could lead to blindness.

[0004] Therefore, the present invention is intended to solve these conventional problems, and its purpose is to eliminate monomers, which are unpolymerized reaction products, from remaining on the lens surface after surface graft polymerization. The object of the present invention is to provide a method for manufacturing contact lenses that is completely non-toxic.

[0005]

[Means for Solving the Problems] In order to solve the above problems, the method for manufacturing a contact lens of the present invention provides a siloxy-substituted ester of acrylic acid or methacrylic acid (

), fluoroalkyl-substituted acrylic acid or methacrylic acid having not more than 20 fluorine atoms represented by the following general formula (

[Chemical formula 12] ), a polyfluoroalkylsiloxy substituted ester of acrylic acid or methacrylic acid represented by the following general formula (

[Chemical formula 13] ), acrylic (methacrylic)oxyalkylsilanol (

[0006]

[Chemical formula 14] ), polyacrylic (methacrylic) represented by the following general formula
Oxyalkylpolysiloxane (

[Chemical formula 15] ), fluorine-containing siloxanyl methacrylate (

[Chemical formula 16] ), a fluorine-containing acrylic acid or methacrylic acid ester monomer (

[Chemical formula 17] ), a fluorine-containing acrylic acid or methacrylic acid ester monomer (

[Chemical formula 18] ), a fluorine-containing diacrylate or dimethacrylate monomer (

[Chemical formula 19] ) and the fluorine-containing cyclic olefin (

Regarding a contact lens base material made from a polymer of an ester compound of acrylic acid or methacrylic acid, which is a copolymer containing at least one of the following, (a) its surface is heated under normal pressure or The method is characterized by comprising a step of performing electric discharge treatment under reduced pressure, (b) a step of graft polymerizing a hydrophilic monomer onto the surface of the base material, and (c) a step of immersing the grafted base material in a solvent. In addition, the above (c
) The solvent in the process is water. Further, the temperature of this water is 20° C. or higher.

[0007] The following are representative compounds represented by the above general formula. Fluorobutylhexamethyltrisiloxanyl methacrylate

[C21] trifluoroethyl methacrylate

[Chemical formula 22] Trifluoropropyltetramethyldisiloxanyl methyl methacrylate

[C23] Hereinafter, the details of the present invention will be shown by examples.

[0008]

【Example】

(Example 1) 10 g of acrylamide was dissolved in distilled water to make 100 ml to prepare an aqueous monomer solution.

Graft polymerization was carried out as follows. 48 wt% r-methacryloxypropyl-tris(trimethylsiloxine) silane, 19 wt% 2,2,2-trifluoroethyl methacrylate, 1,3-bis(r
-methacryloxypropyl)-1,1,3,3-tetrakis(trimethylsiloxy)disiloxane 8 wt%,
Bis(trimethylsiloxy)-r-methacryloxypropylsilanol 7wt%, methacrylic acid 10wt%,
Methyl methacrylate 1wt%, ethylene glycol dimethacrylate 7wt%, 2,2'-azobis(2,4
-isobutyronitrile) (as a polymerization initiator) 0
．． A contact lens base material made of a 25 wt % copolymer was prepared.

The lens base material was placed in a discharge device (electrode spacing 6 cm, interelectrode voltage 270 volts, frequency 60 Hz), and glow discharge treatment was performed for 5 seconds in an argon atmosphere of 0.04 Torr. After the discharge-treated lens base material was exposed to the air, it was placed in a test tube, and the monomer aqueous solution was added in an amount sufficient to submerge the lens base material. This was connected to a vacuum system, the inside of the tube was degassed, and the tube was then vacuum sealed. In this state, the test tube was inserted into a reciprocating shaker (EP-1, manufactured by Taiyo Service Center Co., Ltd.), and graft polymerization treatment on the substrate surface was performed at a constant temperature of 80° C. for 60 minutes while shaking. After the polymerization was completed, the lens was taken out, immersed in pure water set at a predetermined temperature, and rinsed for 3 hours. Set the temperature as shown in Table 1. 1 gram (approximately 100) contact lenses were used at each temperature (sample 1 to
8). On the other hand, for comparison, 1 gram (approximately 100 lenses) of surface-grafted contact lenses made by a conventional method, that is, made by a method that omitted the above-mentioned rinsing step with pure water, was also prepared (Comparative Example 1).

The monomer (acrylamide in this case) remaining on the lens surface was quantified by the method shown below.

[0012] Thoroughly dried contact lenses were ground with a hammer, passed through a 50 mesh sieve to collect exactly 1 gram, and placed in a glass bottle. 50 ml of pure water was added to this, and the mixture was kept at 100°C for 30 minutes in an autoclave. After taking it out from the autoclave and cooling it to room temperature, the supernatant liquid was collected and analyzed by liquid chromatography.

Table 1 shows the peak heights of acrylamide obtained for Samples 1 to 8 and Comparative Example 1. Here, the peak height represents a relative value with that of Comparative Example 1 being 1.0. As is clear from Table 1, the largest amount of acrylamide monomer was detected as a result of the analysis in Comparative Example 1, that is, the conventional method. On the other hand, in the products according to the present invention (samples 1 to 8), almost no acrylamide monomer was detected, especially in samples 3 to 8, that is, when the temperature of the pure water was 20°C or higher in the rinsing step with pure water. It became clear that the acrylamide monomer was completely removed from the lens surface by immersion for a period of time.

In this example, pure water was used as the solvent in the rinsing step, but the solvent is not limited to this, and any solvent may be used as long as it has a certain degree of solubility for the monomer.

[Table 1] (Example 2) 10 g of acrylamide was dissolved in distilled water to make 100 ml to prepare an aqueous monomer solution.

Graft polymerization was carried out as follows. 48 wt% r-methacryloxypropyl tris(trimethylsiloxy)silane, 19 wt% 1,1-dihydroperfluorobutyl methacrylate, 1,3-bis(
r-methacryloxypropyl)-1,1,3,3-tetrakis(trimethylsiloxy)disiloxane 7wt%
, bis(trimethylsiloxy)-r-methacryloxypropylsilanol 8wt%, methacrylic acid 11wt%
, ethylene glycol dimethacrylate 7wt%, 2,
2'-azobis(2,4-isobutyronitrile) 0.2
A contact lens base material made of a 5 wt % copolymer was prepared.

A space made with a 1.5 mm thick spacer was provided between the electrodes of a corona discharge treatment device with an inter-electrode distance of 3.5 cm, an inter-electrode voltage of 15 kilovolts, and a frequency of 60 hertz, and this lens base was Install the materials,
Discharge treatment was performed. Incidentally, discharge treatment was applied to one side and both sides for 40 seconds each. Next, this discharge-treated lens base material was placed in a test tube, and the monomer aqueous solution was added in an amount sufficient to soak the lens base material. This was connected to a vacuum system, the inside of the tube was degassed, and the tube was then vacuum sealed. In this state, the test tube was inserted into a reciprocating shaker (EP-1, manufactured by Taiyo Service Center Co., Ltd.), and graft polymerization treatment on the substrate surface was performed at a constant temperature of 80° C. for 60 minutes while shaking. After polymerization,
The lens was taken out, immersed in pure water set at a predetermined temperature, and rinsed for 3 hours. Set the temperature as shown in Table 2. One gram (approximately 100) contact lenses were used for each temperature (Samples 1-8). On the other hand, for comparison, 1 gram (approximately 100 lenses) of surface-grafted contact lenses made by a conventional method, that is, made by a method that omitted the above-mentioned rinsing step with pure water, was also prepared (Comparative Example 1).

The monomer (acrylamide in this case) remaining on the lens surface was quantified by the method shown below.

[0018] Thoroughly dried contact lenses were crushed with a hammer, passed through a 50 mesh sieve to collect exactly 1 gram, and placed in a glass bottle. 50 ml of pure water was added to this, and the mixture was kept at 100°C for 30 minutes in an autoclave. After taking it out from the autoclave and cooling it to room temperature, the supernatant liquid was collected and subjected to analysis by liquid chromatography.

Table 2 shows the peak heights of acrylamide obtained for Samples 1 to 8 and Comparative Example 1. Here, the peak height represents a relative value with that of Comparative Example 1 being 1.0. As is clear from Table 2, in Comparative Example 1, that is, the conventional method, the largest amount of acrylamide monomer was detected as a result of analysis. On the other hand, in the products according to the present invention (samples 1 to 8), almost no acrylamide monomer was detected, especially in samples 3 to 8, that is, when the temperature of the pure water was 20°C or higher in the rinsing step with pure water. It became clear that the acrylamide monomer was completely removed from the lens surface by immersion for a period of time.

Although pure water was used as the solvent in the rinsing step in this example, the solvent is not limited to this, and any solvent may be used as long as it has a certain degree of solubility for the monomer.

[Table 2] In the examples of the present invention, explanations have been made using contact lenses made of fluorine-based methacrylate, but the same results can be obtained with other hard contact lenses and soft contact lenses such as silicone rubber. It has gained.

Furthermore, similar results were obtained for surface treatments of polyethylene film, polypropylene, polyvinyl chloride, polyvinylidene chloride, acetate, polyester, polyvinyl alcohol, polystyrene, polycarbonate, and various other polymeric materials.

In addition, the above-mentioned materials can be applied to various packaging materials, agricultural water retaining materials, and medical products such as artificial organs.

[0023]

[Effect of the invention] According to the present invention, since the surface graft polymerization treatment is followed by the rinsing treatment in a solvent, no unpolymerized monomer remains on the surface of the contact lens, making it completely non-toxic. You can get contact lenses.

Claims (3)

[Claims] Claim 1: A siloxy-substituted ester of acrylic acid or methacrylic acid represented by the general formula: Fluoroalkyl-substituted acids ( [Chemical formula 2] ), polyfluoroalkylsiloxy-substituted esters of acrylic acid or methacrylic acid ( [
Chemical formula 3), acrylic (methacrylic) oxyalkylsilanol represented by the following general formula (chemical formula 4), polyacrylic (methacrylic) represented by the following general formula
Oxyalkyl polysiloxane (Chemical formula 5), fluorine-containing siloxanyl methacrylate (Chemical formula 6) represented by the following general formula, fluorine-containing acrylic acid or methacrylic acid ester monomer represented by the following general formula ( [Chemical 7] ), a fluorine-containing acrylic acid or methacrylic acid ester monomer ( [Chemical 8] ) represented by the following general formula, a fluorine-containing diacrylate or dimethacrylate monomer ( A polymer of an ester compound of acrylic acid or methacrylic acid, which is a copolymer containing at least one of the following: Regarding a contact lens base material made from a raw material, (a) a step of discharging the surface thereof under normal pressure or reduced pressure, (b) a step of graft polymerizing a hydrophilic monomer on the surface of the base material, and (c) a step of graft polymerization. 1. A method for manufacturing a contact lens, comprising the step of immersing a chemical base material in a solvent. 2. A method for manufacturing a contact lens, wherein the solvent in step (c) according to claim 1 is water. 3. A method for manufacturing a contact lens according to claim 2, wherein the temperature of the water is 20° C. or higher.