JPS62127823A - Soft contact lens - Google Patents

Abstract

PURPOSE:To decrease breakage of a lens during cleaning and handling before and after mounting of the lens by consisting the lens of an acrylate, methacrylate and specific copolymer. CONSTITUTION:This lens consists of 19.9-90mol% acrylate, 9.9-80mol% methacrylate and the copolymer for which 0.1-20mol% crosslinkable monomer having cyclic structure and >=2 functional groups is the nulecule and >=2 number of atoms between the cyclic structure and functional groups is used. The acrylate is exemplified by, for example, an n-butyl acrylate having >=4C of the acrylic group the methacrylate is exemplified by, for example, methylmethacrylate. The crosslinkable monomer is exemplified by, for example, tricyclodecan dimethylol diacrylate, etc. and the compd. expressed by the formula is the example.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a substantially water-free soft contact lens. More particularly, the present invention relates to a substantially water-free soft contact lens with improved mechanical strength.

[Conventional technology]

Currently, commercially available soft contact lenses are made of water-containing polymers such as poly(2-hybyloxyethyl methacrylate) or poly-N-vinylpyrrolidone, and non-water-containing halimers such as polydimethylsiloxane. Soft contact lenses are known.

Furthermore, Mitchell Dien et al. have disclosed a water-free soft contact lens which is mainly made of polyacrylic acid ester and is comfortable to the eyes (Japanese Patent Publication No. 59-33887). These contact lenses are made by first preparing a hard copolymer consisting mainly of acrylic acid, acrylic esters, methacrylic esters, and a small amount of crosslinkable polymer, cutting this into the shape of a contact lens, polishing it, and then cutting it into the shape of a contact lens. The esterification reaction and/or transesterification reaction is carried out in alcohol to produce a non-hydrous soft contact lens.

[Problem that the invention seeks to solve]

However, hydrous soft contact lenses have problems in that they lack shape stability and must be frequently sterilized by boiling to prevent the growth of bacteria. Therefore, there is a need for non-hydrous soft contact lenses that do not require boiling sterilization, but non-hydrous soft contact lenses made of polydimethylsiloxane have a water-repellent surface and do not blend well with the eye (because they do not blend well with the eyes). to the surface parent,
However, there are problems such as the treatment effect decreasing over time. In addition, non-hydrous soft contact lenses by Mitchell Zien et al. do not require boiling sterilization. Although it is easy on the eye, it has low mechanical strength and has the problem that it may break when washed before and after wearing.

The present invention is particularly aimed at improving the mechanical strength of non-hydrous soft contact lenses so that they are more comfortable to the eye.

[Failure to solve the problem]

The present invention substantially comprises acrylic acid esters of 19.9 to 90
Morti, methacrylic acid ester 9.9 to 80 mol %, and a crosslinking monomer having a cyclic structure and two or more functional groups in the molecule, and the number of atoms between the cyclic structure and the functional group is 2 or more. The present invention provides a water-free soft contact lens characterized by comprising a copolymer using a mol ratio of 1 to 20.

Among the monomer components of the copolymer constituting the soft contact lens of the present invention, examples of acrylic esters include n-butyl acrylate, n-pentyl acrylate, and n-hexyl acrylate in which the acrylic group has 4 or more carbon atoms. , n-hebutyl acrylate, 2-ethylhexyl acrylate, n-octyl acrylate, n-
Decyl acrylate, n-h'decyl acrylate, n
-tetradecyl acrylate, n-hexadecyl acrylate, lauryl acrylate, cyclohexyl acrylate, preferably n-butyl acrylate, n-<
Butyl acrylate, n-hexyl acrylate, n-
Acrylic acid alkyl esters such as hebutyl acrylate, 2-ethylhexyl acrylate and n-octyl acrylate, -CH2CH20R, -CH2Cf(
2(OR)CH3, -CH20M2CH20R, -CH
(CH3)CH20R.

-CH2CH2CH2CH20R (in the group, R has 1 carbon number
It is a °-7 alkyl group. ) acrylic acid alkoxyalkyl esters having an alkoxyalkyl group shown in Examples include ethyl acrylate, tetrahydrofurfuryloxyhexanolyte (1 acrylate), and 1,3-dioxolane acrylate.

These acrylic esters can be used in combination.

Among the monomer components of the copolymer constituting the soft contact lens of the present invention, methacrylic acid esters include, for example, methyl methacrylate, ethyl methacrylate, n
-Propyl methacrylate, 1-propyl methacrylate, t-butyl methacrylate, n-butyl methacrylate, n-pentyl methacrylate, n-hexyl methacrylate, 2-ethylhexyl methacrylate, n-
Hebutyl methacrylate, n-octyl methacrylate, n-tecyl methacrylate, n-t'decyl methacrylate, n-tetradecyl methacrylate, n-hexadecyl methacrylate, lauryl methacrylate, preferably n-butyl methacrylate, n-pentyl methacrylate, n Methacrylic acid alkyl esters, alkoxyalkyl ester groups such as -hexyl methacrylate, n-hebutyl methacrylate, 2-ethylhexyl methacrylate, n-octyl methacrylate, n-decyl methacrylate and n-t'decyl methacrylate; O
R) CH3, -CH2Cf(2CH20R, -CH(C
H3) CH20R.

-CH2CH2CH2CH20R (in the group, R has 1 carbon number
-7 alkyl group. ) Methacrylic acid alkoxyalkyl esters having an alkoxyalkyl group represented by
Examples include 2-hydroxyethyl methacrylate, 2-hydroxypropyl methacrylate, tetrahydrofurfuryl methacrylate, phenoxyethyl methacrylate, and tetrahydrofurfuryloxyethyl methacrylate.

These methacrylic esters can be used in combination.

Among the monomer components of the copolymer constituting the soft contact lens of the present invention, the molecule has a cyclic structure and two or more functional groups, and the number of atoms between the cyclic structure and the functional group is 2.
The above, preferably 3 or more crosslinking monomers (hereinafter referred to as
It is simply referred to as a "crosslinking monomer." ), for example, tricyclodecane dimethylol diacrylate, tricyclodecane dimethylol dimethacrylate and their ε-caprolactone adducts, 2-(2-hydroxy-L
l-dimethylethyl)-5-hydroxymethyl-5-ethyl-13-:)oxane diacrylate, 2-(2-
hibiloxy L1-dimethylethyl)-5-hydroxymethyl-5-ethyl-L3-dioxane dimethacrylate, terephthalic acid diglycidyl ester acrylate,
Examples include terephthalic acid diglycidyl ester methacrylate, spiroglycol diglycidyl ether, and the following compounds represented by the following general formulas (I) to (■).

n represents an integer of 1 to 5. ) (In the formula, R is the same group as above, 1m is an integer of 1 to 5, l and n are integers of 1 to 20.) (In the formula, R is the same group as above, m is 1 to 5 an integer of

! and n represents an integer of 3 to 10. ) (In the formula, R is the same group as above, and m and n are integers of 1 to 20.) (In the formula, R is the same group as above, and m and n are integers of 1 to 2o. ) Among the above crosslinkable monomers, preferred are compounds represented by general formula (n), compounds represented by general formula (III), and 2.27-bis(4-acryloxytetraethoxyphenyl)propane. 2'-bis(
Examples include 4-methacryloxytetraethoxyphenyl)propane.

In the present invention, if the number of atoms between the cyclic structure and the functional group in the crosslinkable monomer is 2 or less, particularly 1 or less, the resulting soft contact lens will have insufficient mechanical strength.

The copolymer composed of the above monomers forming the soft contact lens of the present invention includes (11) a method of directly polymerizing the above monomer components in a contact lens-shaped mold; , and a hard copolymer consisting of a crosslinkable monomer is cut into the shape of a contact lens, polished, and then subjected to esterification treatment and/or transesterification treatment in the same manner as the Mitchell-Diene method (Japanese Patent Publication No. 59-33887). It can be obtained by a method of softening by softening.

First, in method (1), a predetermined amount of the monomer component is polymerized in a soft contact lens-shaped mold by a normal radical polymerization reaction. In this polymerization, a method of polymerizing by raising the temperature stepwise in the presence of a peroxide or an azo compound such as benzoyl peroxide or azobisisobutyronitrile as a catalyst, or Examples include a method of polymerizing by irradiating ultraviolet rays in the presence of a photosensitizer such as benzophenone or Michler's ketone.

The amount of monomer used at this time is 199 to 90 mol% of acrylic acid ester, preferably 40 to 75 mol%, and 99 to 80 mol% of methacrylic ester, preferably 2
5 to 60 mol%, and crosslinking monomer 0.1 to 20
It is mol %, preferably 1 to 10 mol. At this time,
If the amount of each monomer used is outside the above range, the mechanical strength and flexibility of the resulting soft contact lens will be impaired. Further, the catalyst is usually used in an amount of 0.01 to 1 part by weight per 100 parts by weight of the monomer.

Next, in the method (2), first, a hard A copolymer is synthesized. In addition to the above-mentioned acrylic esters, methyl acrylate, ethyl acrylate), 1-propyl acrylate, n-propyl acrylate, 1-butyl acrylate, t-butyl acrylate, etc. Examples of the lower alkyl acrylic ester and methacrylic ester include those mentioned above. Also, the same crosslinking monomers as mentioned above can be used.

The amounts of at least one compound selected from acrylic acid and acrylic esters, at least one compound selected from methacrylic acid and methacrylic esters, and crosslinkable additives are determined in the amount of the resulting hard copolymer. The glass transition temperature is preferably 50°C or higher, and the glass transition temperature of the copolymer constituting the soft contact lens obtained by esterification treatment and/or transesterification treatment is preferably 20°C or lower, particularly preferably 0°C or lower. It is adjusted so that

Next, the above-mentioned monomers are polymerized by ordinary radical polymerization, and the catalyst and the amount used in this polymerization, other conditions, etc. are the same as in method (1).

The obtained hard copolymer is cut into a conmecutre/z shape, polished, and then esterified and/or transesterified by immersing it in alcohol.

Alcohols and catalysts used in performing esterification and/or transesterification of hard copolymers cut and polished into the shape of contact lenses are disclosed, for example, in Japanese Patent Publication No. 33887/1987. You can choose from among them.

That is, alcohols include alcohols having 4 or more carbon atoms, examples: tk'i n -7'tanol, n-"?butanol, 1-pentanol, n-hexanol, n-
heptatool, n-octatool, n-nonanol, n
-teca,'-ol, cyclohexanol, benzyl alcohol, cyclobutanol, 2-methylcyclobutanol, 2-methoxyethanol, 2-methoxypropanol, 2-(n-propoxy)-ethanol, 3-(n
-i Roboxy)-n-propertool, 3-methoxy-n
-butanol, 4-(n-propoxy)-n-butanol, 4-ethoxy-n-butanol, etc., preferably n
-butanol, n-''?butanol, n-hexanol, n-heptatool, n-octatool, n-nonanol, n-decamer, and other linear alcohols having 4 to 10 carbon atoms.

The catalyst for mataesterification treatment and transesterification treatment may be a normal esterification catalyst, such as m-sulfonic acid, and the catalyst concentration in the alcohol is 0.2
~10 weight. The reaction conditions are approximately 20°C or higher and approximately 2
A reaction time of about 1 to 100 hours at a temperature below 00°C is sufficient.

The copolymer constituting the soft contact lens obtained by the method (2) above includes acrylic acid, acrylic acid lower alkyl ester, and Up to 20% by weight, preferably up to 10% by weight of the total amount of methacrylic acid may remain after carrying out the esterification and/or transesterification treatment (this improves the mechanical strength of the soft contact lenses of the invention). and flexibility shall not be affected.

〔Example〕

The present invention will be described in detail below with reference to Examples and Comparative Examples, but the present invention is not limited to these Examples.

Example 1 68 mol % of n-butyl acrylate, 30 mol % of 2-ethylhexyl methacrylate and 2 mol % of Z2-bis(4-metachlorooxytetraethoxyphenyl)propane were mixed, and 100 mol % of the monomers were mixed with benzoyl peroxide as a catalyst. After adding 0.2 parts by weight to parts by weight, the mixed solution was poured into a contact lens mold, polymerized at about 40°C for 16 hours, and then heated continuously to 100°C (from 40°C to The temperature was raised to 100° C. for 24 hours), and the polymerization was completed. At this time, the polymerization conversion rate is 100%
Met.

After cooling, the soft contact lens was removed from the mold and cut into strips, and the tensile strength, elongation at break, and initial elastic modulus were measured. The results are shown in Table 1.

Example 2 Polymerization was carried out in the same manner as in Example 1, except that a compound represented by the following general formula was used instead of 2'-bis(4-methacryloxytetraethoxyphenyl)propane to obtain a soft contact lens. Ta.

At this time, the polymerization conversion rate was 100%.

The tensile strength, elongation at break, and initial elastic modulus of the obtained soft contact lens were measured in the same manner as in Example 1. The results are shown in Table 1.

Example 3 A soft contact lens was obtained by polymerizing in the same manner as in Example 1, except that a compound represented by the following general formula was used instead of 22/-bis(4-methacryloxytetraethoxyphenonyl)propane. Ta.

The tensile strength, elongation at break, and initial elastic modulus of the obtained soft contact lens were measured in the same manner as in Example 1. The results are shown in Table 1.

Comparative Example 1 A soft contact lens was obtained by polymerization in the same manner as in Example 1, except that ethylene glycol dimethacrylate was used instead of 2.2'-bis(4-methacryloxytetraethoxyphenyl)propane. The tensile strength, elongation at break, and initial elastic modulus of the obtained soft contact lens were measured in the same manner as in Example 1. The complete table of results is shown.

Example 4 Acrylic acid 68 mol%, 2-ethylhexyl methacrylate 30 mol%, 2-(2-hibiloxy-11-dimethylethyl-5-human 10oxymethyl-5-ethyl-L3
-Dioxane) dimethacrylate was mixed, 0.02 parts by weight of benzoin methyl ether was added as a photopolymerization initiator per 100 parts by weight of the monomer, and the mixture was 15 mm in diameter and 20 mm in height. 1.5 CC was injected into a polyethylene mold and irradiated with ultraviolet rays at room temperature under a nitrogen atmosphere to polymerize for 8 hours. At this time,
The polymerization conversion rate was 100%.

After polymerization, the obtained block copolymer was cut to a diameter of 15 mm.
After making a cage into the shape of a contact lens with a thickness of about 0.5 mm and polishing, the copolymer shaped like a contact lens was immersed in n-butyl alcohol, 1 part by weight of concentrated sulfuric acid was added, and the mixture was heated at reflux temperature for 24 hours. It was reacted and esterified. At this time, the esterification rate and transesterification rate were each 95% or more. After the reaction, it was washed with n-butyl alcohol and dried to obtain a soft contact lens. The tensile strength, elongation at break, and initial elastic modulus of the obtained soft contact lens were measured in the same manner as in Example 1. The results are shown in Table 1.

Comparative Example 2 2-(2-human90x-1,1-dimethylethyl-5
-hydroxymethyl-5-ethyl-L3-)oxane)
Polymerization was carried out in the same manner as in Example 2 except that L4-butanediol dimethacrylate was used instead of dimethacrylate,
A soft contact lens was obtained by esterification. The tensile strength, elongation at break, and initial elastic modulus of the obtained soft contact lens were measured in the same manner as in Example 1. The results are shown in Table 1.

(1) Tensile strength, (2) elongation at break, and (3) initial elastic modulus were measured using Autograph DSS-2000 (manufactured by Shimadzu Corporation) at a tensile speed of 50 mm/lnm.

〔Effect of the invention〕

The soft contact lenses of the present invention fit better into the eyes than conventional water-containing soft contact lenses and Tsubo water-containing soft contact lenses, and have superior mechanical strength and flexibility, so they may break during cleaning operations before and after wearing the soft contact lenses. This has the effect that there are fewer things to do.

Claims (1)

[Claims] Acrylic acid ester 19.9 to 90 mol%, methacrylic acid ester 9.9 to 80 mol%, and has a cyclic structure and two or more functional groups in the molecule, and the number of atoms between the cyclic structure and the functional group is 2 or more crosslinking monomer 0.1~
A non-water-containing soft contact lens comprising a copolymer containing 20 mol%.