JPS62160419A - Material for contact lens - Google Patents

Abstract

PURPOSE:To obtain a rigid contact lens having high permeability for oxygen by using a copolymer consisting of ditertiary butyl fumarate expressed by the specified structural formula, and fumaric acid diester expressed by the specified structural formula, as essential components. CONSTITUTION:A contact lens is prepd. using a copolymeric material consisting of ditertiary butyl fumarate having high permeability for oxygen, expressed by the specified structural formula I, and fumaric acid diester having high permeability for oxygen, high transparency and high mechanical strength, expressed by the general formula II, as essential components. By this method, a rigid contact lens of sufficient quality having high permeability for oxygen and desired strength is obtd.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to a novel contact lens material. More specifically, the present invention relates to contact lens materials having high oxygen permeability.

[Prior art and its problems] Traditionally, glass materials have been mainly used as contact lens materials, but today polymethyl has superior machinability and elasticity and is lighter than glass materials. Contact lens materials made of methacrylate have been used.

However, since contact lens materials made of polymethyl methacrylate have low oxygen permeability, there is a problem in that when the contact lenses are worn for a long period of time, they cause metabolic disorders in the corneal tissue.

Therefore, in recent years, research has been carried out on contact lens materials with excellent oxygen permeability that can replace polymethyl methacrylate.
Developments are underway, including those based on silicone rubber such as polydimethylsiloxane, and those in which vinyl polymerization groups are introduced into (poly)organosiloxane, which is then polymerized with other vinyl monomers.

Contact lens materials mainly composed of silicone rubber such as polydimethylsiloxane have excellent oxygen permeability, but because they exhibit water repellency, they are usually subjected to electrical discharge treatment before use.

However, even if the above-mentioned hydrophilic treatment is applied, the hydrophilicity decreases during use, and the material is flexible, so the phenomenon of adsorption to the eye is observed, causing corneal damage. There is a problem.

Introducing vinyl polymerization groups into (poly)organosiloxane,
For those copolymerized with other vinyl monomers, the oxygen permeability is mainly derived from the organosiloxane site, so the oxygen permeability is lower than that of silicone rubber, but the oxygen permeability of the hard and transparent acrylic resin is lower than that of silicone rubber. It is possible to improve oxygen absorption in the cornea when worn as a contact lens, and prevent a decline in corneal function due to oxygen deficiency.

However, in order to copolymerize (poly)organosiloxane with a vinyl polymerization group introduced with an acrylic monomer and provide contact lenses with sufficient oxygen permeability,
The monomer must be added in large quantities. As a result, the obtained copolymer has problems in that it has poor machinability during the production of contact lenses and also has poor lens toughness. On the other hand, in order to maintain hardness that can withstand machining during lens manufacturing, it is not possible to add a large amount of (poly)organosiloxane with vinyl polymerization groups introduced, and if the amount added is within that range, continuous wear is not possible. Contact lens materials with sufficient oxygen permeability to do so have not been changed.

[Problems to be Solved by the Invention] Therefore, the present inventors solved the drawbacks of the prior art as described above, and developed a material that has the hardness and stiffness desirable for a hard contact lens, and has improved brittleness. As a result of intensive research to develop a hard contact lens that has even higher oxygen permeability than conventional oxygen permeable hard contact lenses, we discovered that ditertiary butyl fumarate and silicone fumarate ( The present invention was completed based on the discovery that a contact lens material having excellent oxygen permeability and appropriate mechanical strength can be obtained by using a copolymer containing fumaric acid diester) as an essential monomer component. reached.

Means for Solving Problems c] That is, the present invention provides ditertiary-butyl fumarate represented by formula (I): and general formula (■): (where m and n are 1 or 3; R1, deceased; R3,
R4, R5 and R6 are methyl groups or? ! The present invention relates to a contact lens material comprising a copolymer containing as an essential component a tummaric acid diester represented by 13-O-Sl-CI+3.

[Example] Formula (I) used in the present invention: Ditert-butyl fumarate (hereinafter referred to as D
Among fumarate compounds, tBF is an extremely homopolymerizable monomer, and its homopolymer exhibits a certain degree of oxygen permeability, but is extremely hard and brittle.

On the other hand, general formula (■): RJ lIc-CoyunC11!
→ “Si R2 (wherein I and n are 1 or 3;
R1, R2, R3, R4, R5 and R6 are methyl groups or? ■! 3 10 -St-C113) DSiAP (hereinafter referred to as DSiAP) does not substantially homopolymerize, but it easily copolymerizes with DtBF and has excellent oxygen permeability and transparency. and a component for obtaining a contact lens material having appropriate mechanical strength.

Examples of the DSiAF include bis(3-()limethylsilyl)propyl) fumarate, bis(3-(pentamethyldisiloxanyl)propyl) fumarate, and bis(
3-(1,3,3,3-tetramethyl-1-(trimethylsilyl)oxy)disiloxanyl)propyl) fumarate, bis(3-(3,3,3-trimethyl-1,1-
Bis((trimethylsilyl)oxy)disiloxanyl)
(propyl) fumarate, (3-(trimethylsilyl)propyl)(3-(pentamethyldisiloxanyl)propyl) fumarate, bis((pentamethyldisiloxanyl)methyl) fumarate, etc.; The species or two or more species are used in an adjusted amount of 5 to 50 mole parts, preferably 20 to 50 mole parts, based on 100 mole parts of the total monomer amount. If the amount used is less than 5 mol parts, the oxygen permeability will decrease, and if it exceeds 50 mol parts, DSiAF will not substantially homopolymerize and will remain as a monomer, resulting in a decrease in the degree of polymerization and polymerization rate. descend.

Further, from the viewpoint of polymerization rate, DSIAF in which ω and n in general formula (1) are both 3 is preferably used.

It is also possible to copolymerize by adding a fumaric acid diester other than the above, for example, bis(trifluoroethyl) fumarate is preferably used, but the amount used is 0 to 100 mole parts per 100 mole parts of the total amount of monomers. 45 mole parts,
Particularly preferred is 0 to 30 parts by mole. If the amount used exceeds 45 mole parts, the resulting polymer will lose its transparency, and since the monomer will not substantially homopolymerize, it will remain as a monomer, resulting in a decrease in the degree of polymerization and polymerization rate.

In the copolymer according to the present invention, in addition to the above fumaric acid diester, various monomers can be used as copolymerization components to modify the properties of the copolymer in accordance with various purposes. .

Crosslinking monomers are effective for the purpose of stabilizing the size, power (power), and shape of Kositact lenses, as well as improving chemical resistance. Specific examples of such crosslinking monomers include diallyl fumarate, allyl methacrylate, allyl acrylate, trimethylolpropane trimethacrylate, trinotyolpropane triacrylate, ethylene glycol diacrylate, ethylene glycol dimethacrylate, vinylbenzene, etc. It is preferable to select and use one or more types from these. In addition, the amount used is 10
It is preferably in the range of about 0 to 20 mole parts relative to 0 mole part.

In order to impart hydrophilicity to the resulting copolymer and obtain a hard contact lens with good water wettability, it is preferable to use a hydrophilic monomer. Examples of such hydrophilic monomers include 2-hydroxyethyl methacrylate, 2-hydroxyethyl acrylate, N-vinylpyrrolidone, 3-methyl-1-buten-3-ol, and one or more of these monomers. It is preferable to select and use. The amount used is preferably in the range of about 0 to 20 parts by mole based on 100 parts by mole of the total monomer mixture to be subjected to copolymerization. It should be noted that if these hydrophilic tops are used in an amount exceeding the above range, the oxygen permeability will decrease, which is not preferable.

Instead of or in addition to the use of the hydrophilic monomer, the obtained hard contact lens may be subjected to a discharge treatment such as corona discharge or plasma discharge, or a hydrophilic monomer may be graft-polymerized after the discharge treatment, or hydrochloric acid or It is also possible to impart effective hydrophilic properties to the surface by treatment with a strong acid such as nitric acid.

In addition, in the present invention, monomerized dyes such as Seikagen-Roreal Black (manufactured by Dainichiseika Chemical Co., Ltd.) and 2-hydroxy-5-acryloxyphenyl-2-hydroxybenzotriazole may be used as necessary. It is also possible to use monomerized ultraviolet absorbers. It is preferable to use these monomers in an amount of 5% by weight or less based on the total amount of the monomers in order to maintain high oxygen permeability.

The monomer mixture is copolymerized using a conventional radical polymerization method at a temperature in the range of 50 to 110°C. Examples of the polymerization initiator that can be used include benzoyl peroxide, azobisisobutyronitrile, and azobisdimethylvaleronitrile, and one or more of these may be selected and used. The amount used is 0.01-100 mole parts of the total monomer.
Preferably it is 1.0 mole part.

The monomer mixture can be molded into a contact lens by a conventional method. For example, the copolymerization reaction of the monomer mixture is carried out in a mold corresponding to the shape of a contact lens, the shape is directly molded into the shape of a contact lens, and if necessary, this is subjected to mechanical finishing processing such as cutting or polishing. can do.

In addition, after copolymerization is carried out in a suitable mold or container to obtain a block-shaped, plate-shaped or round bar-shaped material, the material is formed into a contact lens of a desired shape using ordinary mechanical processing methods such as cutting and polishing. Good too.

Alternatively, the polymer obtained by the above method may be dissolved in a suitable solvent, the resulting solution may be injected into a mold, the solvent may be removed, and the molded product may be subjected to mechanical processing. In this case, the oxygen permeability coefficient is slightly improved compared to a molding method that does not use a solvent.

It has even better oxygen permeability than the oxygen permeable contact lens of the present invention obtained in this manner, and also has appropriate mechanical strength.

Next, the contact lens of the present invention will be explained in more detail with reference to Examples, but the present invention is not limited to these Examples.

Example 1 55 mole parts of ditertiary-butyl fumarate, bis(3
45 mol parts of -(3,3,3-)dimethyl-1,1-bis((trimethylsilyl)oxy)disiloxanyl)propyl fumarate and 0.1 mol part of benzoyl peroxide as a polymerization initiator were placed in a glass test tube. , reduced pressure (10'
The mixture was sealed and polymerized at 70°C for 24 hours. After that, the package was opened, the polymer was taken out, and another 10
Heated at 0°C for 3 hours.

The obtained colorless and transparent copolymer was machined by cutting and polishing to obtain a hard contact lens.

The oxygen permeability coefficient was measured using a Seikaken film oxygen permeability meter in 0.9% physiological saline at 35°C.
Measurements were made on a test piece of 1 nLI1, thickness 0, and 2 m111.

As a result, the oxygen permeability coefficient was 117. OX 1O-IQ
[cII13(STP)・Cal/Cl2IISeC・
C11g].

Example 2 Ditert-butyl fumarate and bis(3-(3,3
, 3-) The experiment was conducted in the same manner as in Example 1, except that the blending ratio with riftyl-1,1-bis((trimethylsilyl)oxy)disiloxanyl)propyl fumarate was changed to 80 parts by mole = 20 parts by mole, I obtained the desired hard contact lenses.

As a result, the oxygen permeability coefficient was 69.2x IQ-IQ [
ca+3(STP)・Cff1/Cm2・SeC-CI
Ig].

Examples 3-12 Ditertiary-butyl fumarate, bis(3-(3,3
, 3-trimethyl-1,1-bis((trimethylsilyl)oxy)disiloxanyl)propyl fumarate, bis(3-()limethylsilyl)propyl) fumarate, bis(2,2,2-trifluoroethyl) fumarate as the first A hard contact lens was produced in the same manner as in Example 1, except that the composition was adjusted to have the composition shown in the table, and the oxygen permeability coefficient was measured.

The results are also listed in Table 1.

[Margins below] [Effects of the Invention] The contact lens material of the present invention contains ditertiary butyl fumarate exhibiting oxygen permeability and fumaric acid diester exhibiting excellent oxygen permeability, transparency, and appropriate mechanical strength as essential components. Because it contains such a substance, it has the effect of being able to be used as a contact lens that exhibits excellent oxygen permeability and has appropriate mechanical strength.

Claims (1)

[Claims] 1 Formula (I): ▲There are mathematical formulas, chemical formulas, tables, etc.▼ Ditertiary butyl fumarate represented by (I) and general formula (II): ▲There are mathematical formulas, chemical formulas, tables, etc.▼ (II) (where m and n are 1 or 3; R_1, R_2, R
_3, R_4, R_5 and R_6 are methyl groups or a contact lens material made of a copolymer containing fumaric acid diester represented by ▲ (numerical formula, chemical formula, table, etc.) as an essential component.