JPH04180012A - Production of contact lens - Google Patents

Abstract

PURPOSE:To eliminate the nonuniformity of a monomer soln. at the time of graft polymn. and to allow a uniform surface graft treatment by executing the graft polymn. treatment onto the surface of a contact lens base material while applying oscillation thereto. CONSTITUTION:The contact lens base material consisting of a copolymer of alkyl fumarate, siloxanyl fumarate (expressed by constitutional formula I), fluoroalkyl fumarate, and methyl methacrylate is installed in a discharge device and is subjected to a glow discharge treatment. After the lens base material is exposed into the air, the material is put into a test tube and the monomer soln. essentially consisting of acrylamide is added into the test tube in the amt. at which the lens base material is sufficiently immersed therein. The test tube is then connected to a vacuum system and the inside of the tube is deaerated to execute vacuum sealing of the tube. The test tube is inserted into a reciprocating shaking machine and the graft polymn. treatment on the surface of the lens base material is executed while the oscillation is applied to the base material.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a manufacturing method for obtaining a hard contact lens that permanently maintains surface wettability and is comfortable to wear.

[Prior 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 improve the wettability of the lens surface by graft polymerizing acrylamide, which is a hydrophilic polymer, onto the surface of the contact lens. 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 solution of 100% water. Next, after removing dissolved oxygen, this is heated and subjected to polymerization treatment. Conventionally, this polymerization process was carried out with the polymerization vessel stationary.

[Problems to be Solved by the Invention] However, in the above-mentioned conventional technology, the concentration distribution in the Senzummer solution becomes non-uniform during the polymerization process, which causes the grafting state of the surface of the contact lens base material to become uneven. It also lacked uniformity, and some parts of the surface became cloudy.

Therefore, in order to solve these conventional problems, the present invention aims to eliminate the non-uniformity of the solution during graft polymerization and to create a contact lens that enables homogeneous surface grafting. The purpose is to provide a manufacturing method.

[Means for Solving the Problems] In order to solve the above problems, the method for manufacturing a contact lens of the present invention includes: (a) at least an alkyl methacrylate, an alkyl fumarate/fluoroalkyl fumarate, and a siloxanyl fumarate (H ○ 1t A-0-C-C=C-C-0-A' ++ 1 H In the formula, A and A' are selected from the group consisting of C1 to C5 alkyl groups or D groups, and D has a structural formula In the formula, X and Y are selected from the group consisting of a C+ to C5 alkyl group and a Z group, Z is a group having the structural formula %, and B represents an 01 to C5 alkyl group.

k, 1. m and n represent Ol or a positive integer. ) of a contact lens base material made from a polymer of an ester compound of methacrylic acid and fumaric acid, which is a copolymer with A method for manufacturing a contact lens comprising a step of immersing it in a solution containing as a main component, and (C) a step of graft polymerizing acrylamide onto the surface of the base material, wherein the polymerization treatment in the step (C) is oscillated. It is characterized by being performed while giving.

In addition, the following are mentioned as typical ester compounds of fumaric acid.

Dimethyl fumarate Bis(pentamethyldisiloxanylmethyl) fumarate CH3CH30HCH3CH3 Bis(trifluoroethyl) fumarate The details of the present invention will be illustrated below with reference to Examples.

[Example 1] Crosslinking agent N,N'-methylenebisacrylamide 2
．． Dissolve 5g of acrylamide and 10g of acrylamide in distilled water.
0 ml, and a monomer aqueous solution was prepared.

Graft polymerization was carried out as follows. A contact lens base material made of a copolymer of alkyl fumarate, siloxanyl fumarate, fluoroalkyl fumarate, and methyl methacrylate 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. Four sets of discharge-treated lens substrates exposed to the air were placed in test tubes, and the monomer aqueous solution was added in an amount sufficient to fully submerge the lens substrates. 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. . Completion of polymerization
The presence or absence of cloudiness on the treated surface was evaluated using an optical microscope. still,
The rocking conditions (swing period, amplitude) of the reciprocating shaker were set as shown in Table 1, and six samples (samples 1 to 6) were studied.

On the other hand, for comparison, we also investigated the surface graft polymerization treatment without shaking as usual (Comparative Examples 1 to 6).
).

As is clear from Table 1, all of the samples subjected to shaking during graft polymerization (Samples 1 to 6) had good surface conditions, with no clouding or the like. On the other hand, as a result of observation under an optical microscope, those in which no shaking was applied during polymerization (Comparative Examples 1 to 6) were found to have a cloudy part over a part or the entire surface.

From the above results, it has become clear that the uniformity of the concentration of the 1,2-summer solution can be ensured by applying agitation during graft polymerization, and that this is very effective in improving the surface grafting state.

Table 1: O Good surface condition (no cloudiness)
．． Dissolve 5g and 10g of acrylamide in distilled water.
00ml and prepare a 1.7' water solution.

Graft polymerization was carried out as follows. Alkyl fumarate, siloxanyl fumarate, fluoroalkyl fumarate 1. A contact lens base material made of a copolymer of methyl methacrylate was prepared. Interelectrode distance 3.5
Centimeters, meters, thickness 1.5 cm between the electrodes of a corona discharge treatment device with an interelectrode voltage of 15 kilovolts and a frequency of 60 hertz.
This lens base material was placed in a space created with a millimeter spacer, and electrical 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 kept at a constant temperature of 80°C while being shaken for 60 minutes. Afterwards, the presence or absence of white turbidity on the treated surface was examined optically. Evaluation was made using a microscope. The rocking conditions (swing period, amplitude) of the reciprocating shaker were set as shown in Table 2, and six samples (sample 1 to 6) were prepared.
I thought about it.

On the other hand, for comparison, we also investigated the surface graft polymerization treatment without shaking as usual (Comparative Examples 1 to 3).
6).

As is clear from Table 2, all of the samples subjected to shaking during graft polymerization (Samples 1 to 6) had good surface conditions, with no clouding or the like. On the other hand, as a result of observation under an optical microscope, those in which no shaking was applied during polymerization (Comparative Examples 1 to 6) were found to have a cloudy part over a part or the entire surface.

From the above results, it has become clear that the uniformity of the concentration of the Senzummer solution can be ensured by applying agitation during graft polymerization, and that this is very effective in improving the surface grafting state.

Table 2 ○ Good surface condition (no clouding) Similar results have been obtained with soft contact lenses such as silicone rubber.

Furthermore, similar results were obtained for surface treatments of polyethylene film, polyglopylene, polyvinyl chloride, polyvinylidene chloride, acetate, polyester, polyvinyl alcohol, polystyrene, polycarbonate, and various other polymeric materials. In addition, the above-mentioned materials can be used in various packaging materials, agricultural water retaining materials, and medical products such as artificial organs.

[Effects of the Invention] As described above, according to the present invention, the concentration uniformity of the monomer solution is ensured by applying shaking during graft polymerization, which is extremely effective in improving the surface grafting state. It was revealed that the effect was large.

that's all

Claims (1)

[Claims] (a) At least an alkyl methacrylate, an alkyl fumarate, a fluoroalkyl fumarate, and a siloxanyl fumarate (▲There are numerical formulas, chemical formulas, tables, etc.▼ In the formula, A and A' are C_1 to C_5. It is selected from the group consisting of alkyl groups or D groups, and D is a group having the structural formula ▲ Numerical formula, chemical formula, table, etc. ▼ In the formula, X and Y are a group consisting of C_1 to C_5 alkyl groups and Z group. Z is a group having the structural formula ▲There are mathematical formulas, chemical formulas, tables, etc.▼, and B represents an alkyl group of C_1 to C_5. k, l, m, and n are 0 or a positive integer. (b) a step of discharging the surface of the contact lens base material made from a polymer of an ester compound of methacrylic acid and fumaric acid, which is a copolymer with A contact lens manufacturing method comprising the steps of: immersing acrylamide in a monomer solution containing acrylamide as a main component; and (c) grafting acrylamide onto the surface of the base material. A contact lens manufacturing method characterized in that the manufacturing method is performed while applying motion.