JPH077157B2 - Oxygen permeable contact lens - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to an oxygen-permeable contact lens comprising a polymer having siloxanylalkyl (meth) acrylate and an alkyl (meth) acrylate monoester as main constituents. .

[Conventional technology]

Conventionally, two types of contact lenses are known, one based on polymethylmethacrylate and the other based on poly-2-hydroxyethylmethacrylate. Contact lenses manufactured from these substrates are It has good transparency and is widely used.

However, contact lenses based on polymethylmethacrylate have excellent transparency, dimensional stability, and mechanical strength, but have extremely low oxygen permeability. On the other hand, poly-
Contact lenses based on 2-hydroxyethyl methacrylate are flexible and have relatively good oxygen permeability and a good wearing feel, but poor mechanical strength and dimensional stability. Also, a lens made of silicone rubber is known as a contact lens having good oxygen permeability,
The lens has the drawbacks that it is difficult to machine, and because it is hydrophobic, it does not wet well and is easily soiled.

In recent years, as a method for further improving oxygen permeability, an attempt to use a silicone polymer as a base material of a contact lens has been proposed, for example, Japanese Patent Publication No. 52-33502.
A copolymer of a siloxanyl alkyl ester having a specific group and a (meth) acrylic acid ester is disclosed in JP-A-54-24.
No. 047 discloses a compound having an unsaturated group at both ends of polysiloxane and a copolymer of the compound and an alkyl methacrylate. A copolymer of siloxanylalkyl (meth) acrylate having a structure and a polymerizable acrylic material such as alkylmethacrylate is disclosed in JP
In 58-7124, a copolymer of a siloxanylalkyl ester having a specific structure, a (meth) acrylic acid ester and an itaconic acid ester, and in JP-A-58-113911,
Siloxane having at least two polymerizable groups in one molecule has been disclosed, and contact lenses made of these silicone polymers are expected to be further developed.

[Problems to be solved by the invention]

However, although the above silicone-based contact lenses are almost satisfactory in terms of transparency, they are not necessarily satisfactory in terms of oxygen permeability. There are some cases in which the oxygen permeability shows a high value to some extent, but these are industrially difficult to implement because the process for obtaining a contact lens material is complicated and harsh conditions are adopted.

Therefore, an object of the present invention is to provide a contact lens which is excellent in transparency and oxygen permeability and which can be manufactured industrially advantageously.

[Means for solving problems]

The present inventors have earnestly studied to achieve the above object,
The present invention has been achieved. That is, the present invention is represented by the following general formula (Wherein R ₁ is a hydrogen atom or a methyl group, l is 1 or 2 or 3, m is 1 or 2, and n is 3-m). An oxygen-permeable contact lens consisting of a polymer essentially consisting of -80 parts by weight and 80-20 parts by weight of at least one C1-10 (meth) acrylic acid alkyl ester.

The contact lens of the present invention comprises at least 1 of siloxanylalkyl (meth) acrylate represented by the above general formula.
It is produced from a polymer having as a main component a (meth) acrylic acid alkyl monoester having 1 to 10 carbon atoms, and such siloxanylalkyl (meth) acrylate is specifically represented by the following (I) and It is shown by the formula (II).

In the formula, R ₁ is a hydrogen atom or a methyl group, and l is 1 or 2
Or 3, but more preferably R ₁ is a methyl group,
1 is 3 siloxanylalkyl (meth) acrylate. Specific examples of such siloxanylalkyl (meth) acrylate include 3-methacryloxypropyl- [bis- (trimethylsiloxy) methylsiloxy]-
Examples include dimethylsilane and 3-methacryloxypropyl-bis- [bis- (trimethylsiloxy) methylsiloxy] methylsilane.

The siloxanylalkyl methacrylate used in the present invention includes the corresponding (meth) acryloxyalkylsilyl chloride or (meth) acryloxyalkylsilyl alkoxide, and bis (trimethylsiloxy) methylsilyl chloride or bis (trimethylsiloxy). It can be easily obtained by hydrolysis and condensation with methylsilyl alkoxide.

Examples of the (meth) acrylic acid alkyl monoester having 1 to 10 carbon atoms used in the present invention include hydrophobic ones such as methyl (meth) acrylate, ethyl (meth) acrylate, and 2-ethylhexyl (meth) acrylate. Examples thereof include (meth) acrylic acid alkyl monoesters. These may be used alone or in combination of two or more, but practically, methyl methacrylate or one containing methyl methacrylate as a main component is preferable.

In the present invention, the siloxanylalkyl (meth) acrylate represented by the above general formula is 20 to 80 parts by weight, and the (meth) acrylic acid alkyl monoester having 1 to 10 carbon atoms is
It is used in 80 to 20 parts by weight, but from the viewpoint of the definition of the apex refractive power and the oxygen permeability, siloxanylalkyl (meth) acrylate is 40 to 60 parts by weight and has 1 to 10 carbon atoms (meth). ) It is preferred to carry out the alkyl acrylate monoester in an amount of 60 to 40 parts by weight. Siloxanylalkyl (meth)
When the amount of acrylate is less than 20 parts by weight (when the amount of (meth) acrylic acid alkyl monoester having 1 to 10 carbon atoms is more than 80 parts by weight), the lens has low oxygen permeability and siloxanylalkyl (meth) acrylate. Is more than 80 parts by weight (the amount of the alkyl (meth) acrylate monoester having 1 to 10 carbon atoms is less than 20 parts by weight), it becomes too soft and it is difficult to manufacture a lens.

Further, in the present invention, in order to maintain thermal shape stability, up to 20 parts by weight, relative to 100 parts by weight of the total amount of the siloxanylalkyl methacrylate and the (meth) acrylic acid alkyl monoester having 1 to 10 carbon atoms. It is preferable to add a cross-linking agent within the range to polymerize to obtain a polymer. Examples of such a cross-linking agent include polyfunctional compounds such as ethylene glycol dimethacrylate and trimethylolpropane trimethacrylate. These may be mixed and used, but if used in an amount of more than 20 parts by weight, they become hard and brittle.

Further, in the present invention, in order to reduce the contact angle with water,
Hydrophilic hydroxy esters such as hydroxyethyl methacrylate may be added in a small amount as long as the effect of the present invention is not impaired.

The contact lens of the present invention is produced by first polymerizing the siloxanylalkyl (meth) acrylate and alkyl (meth) acrylate monoester to produce a polymer (that is, a material for contact lenses), and cutting and polishing the material. It is manufactured by The polymerization operation is not particularly limited, and can be carried out by a usual polymerization operation, for example, a polymerization initiator which generates a normal free radical in the above components, for example, benzoyl peroxide, lauroyl peroxide, diisopropyl peroxydicarbonate, It can be produced by adding 0.01 to 1% by weight of azobisisobutyronitrile or the like, placing it in a suitable container to remove oxygen, then sealing and polymerizing by heating.
Further, after purging oxygen, polymerization may be carried out while sealing nitrogen, or ultraviolet polymerization may be carried out.

A contact lens can be produced from the polymer by a spin cast method, a cast molding method, or a lace cut method.

Hereinafter, the present invention will be specifically described with reference to Examples, but the present invention is not limited thereto.

〔Example〕

In the following examples, oxygen permeability was measured by a Seikaken film oxygen permeability meter at 25 ° C. using a lens or disk having a center thickness of about 0.2 mm.

Example 1 Synthesis of 3-methacryloxypropyl- [bis- (trimethylsiloxy) methylsiloxy] -dimethylsilane In an Erlenmeyer flask, 4 g of distilled water, 25 g of concentrated hydrochloric acid and 25 ml of ether were placed, and 12.7 g of 3-ethoxyheptamethyl was added thereto. Trisiloxane (bis- (trimethylsiloxy) methylsilylethoxide) Was added and stirred. 10 ml of ether and 10 g of 3-methacryloxypropyldimethylchlorosilane were placed in a dropping funnel, stirred uniformly, and then added dropwise to the Erlenmeyer flask.
During this reaction operation, the inside of the Erlenmeyer flask was stirred, and a cooling operation was added from the outside of the Erlenmeyer flask so that the temperature of the contents did not exceed 25 ° C.

After the dropping was completed, stirring was continued at room temperature for 24 hours. The reaction mixture was separated, and the ether layer was washed several times with distilled water until the washings became neutral. The ether layer was transferred to a rotary evaporator to remove the ether, then 60 ° C, 1 mmHg
The low boiling substance is distilled off with a liquid 3-methacryloxypropyl-
19.1 g of [bis- (trimethylsiloxy) methylsiloxy] -dimethylsilane was obtained.

Copolymerization with Comonomer 5.00 g of the liquid substance and 4.50 g of methyl methacrylate (MMA),
Ethylene glycol dimethacrylate (EG
0.50 g of DMA) was placed in a polypropylene test tube, 0.1% of azobisisobutyronitrile was added as a catalyst, the atmosphere was replaced with nitrogen, the lid was closed, and the tube was immersed in a constant temperature water bath at 55 ° C. for 24 hours. Then, heat treatment was carried out at 70 ° C. for 1 hour and 130 ° C. for 2.5 hours to obtain a colorless and transparent polymer.

A cylinder having a height of about 7 mm was cut out from this polymer, and a contact lens was prepared from this cylinder by the lace cut method. Oxygen permeability measured using this lens is 18.6 × 10 ^-11 CC (STP) · cm / cm ² · sec
・ It was mmHg (25 ℃).

Example 2 Synthesis of 3-methacryloxypropyl-bis- [bis- (trimethylsiloxy) methylsiloxy] methylsilane 35 g of concentrated hydrochloric acid and 35 ml of ether were placed in an Erlenmeyer flask and stirred. Meanwhile, add 35 ml of ether and 45.9 g of 3-to the dropping funnel.
Ethoxyheptamethyltrisiloxane and 20 g of 3-methacryloxypropyldimethoxymethylsilane were added and uniformly stirred, and then added dropwise to the Erlenmeyer flask.
Thereafter, the same procedure as in Example 1 was carried out to obtain 57.5 g of liquid 3-methacryloxypropyl-bis- [bis- (trimethylsiloxy) methylsiloxy] methylsilane.

Copolymerization with Comonomers The same polymerization operation as in Example 1 was carried out using 5.00 g of the liquid material, 4.50 g of MMA and 0.50 g of EGDMA to obtain a colorless and transparent polymer.

A cylinder similar to that used in Example 1 was cut out from the polymer to produce a contact lens by the lace cut method, and the machinability was good. Also, oxygen permeability is 22.3 × 10 ^-11 CC
(STP) · cm / cm ² · sec · mmHg (25 ° C).

Example 3 A copolymer was prepared in the same manner as in Example 1 except that 3.00 g of 3-methacryloxypropyl- [bis- (trimethylsiloxy) methylsiloxy] -dimethylsilane obtained in Example 1 and 7.00 g of methyl methacrylate were used. Got A contact lens was produced from the copolymer by the same method as in Example 1, and the oxygen permeability was measured by the same method. As a result, 14.0 × 10 ⁻¹¹ CC (S
TP) ・ cm / cm ²・ sec ・ mmHg (25 ℃).

Examples 4-5 3-methacryloxypropyl- [bis- (trimethylsiloxy) methylsiloxy] -dimethylsilane obtained in Example 1 4.00 g and 5.50 g, methyl methacrylate 5.00 g
And 4.50 g, ethylene glycol dimethacrylate 1.0
Contact lenses were produced in exactly the same manner as in Example 1 except that the amounts were 0 g and 1.50 g, respectively (Examples 4 and 5).

When the oxygen permeability of the contact lens was measured, it was 16.6 × 10 ^-11 and 18.0 × 10 ^-11 CC (STP) · cm / cm ² · sec, respectively.
・ It was mmHg (25 ℃).

Example 6 7.00 g of 3-methacryloxypropyl- [bis- (trimethylsiloxy) methylsiloxy] -dimethylsilane obtained in Example 1 was added, 3.00 g of methyl methacrylate and 1.50 g of ethylene glycol dimethacrylate (EGDMA) were added. A copolymer was obtained. A contact lens was produced from the copolymer by the same method as in Example 1, and the oxygen permeability was measured by the same method, which was 29.5 × 10 ⁻¹¹ CC (STP) · cm / cm ² · sec.
・ It was mmHg (25 ° C.), and there was no problem in the performance as a contact lens, but the copolymer tended to be a little soft. Further, the appearance of the apex refractive power was slightly unclear as compared with the contact lenses of Examples 4 and 5.

Comparative Examples 1 to 4 Siloxanylalkyl (meth) represented by the following formula (III) or the following formula (IV), which is disclosed in JP-B-52-33502.
When a contact lens was manufactured in the same manner as in Example 1 using 3.00 g of acrylate and 7.00 g of methyl methacrylate, the machinability was poor, and the occurrence rate of edge chips was
40% when the compound of the following formula (III) is used,
It was 20% when the compound of V) was used. The oxygen permeability of the obtained contact lens is 1.8 × 10 ^-11 CC (STP) · cm / cm ² · sec when the compound of the following formula (III) is used.
・ When using the compound of mmHg (25 ℃) and the following formula (IV)
It was 3.0 × 10 ^-11 CC (STP) · cm / cm ² · sec · mmHg (25 ° C).

A method similar to that of Example 1 using 3.00 g of siloxanylalkyl methacrylate represented by the following formula (V) or the following formula (VI) and 7.00 g of methyl methacrylate disclosed in JP-A-55-102613. When I made contact lenses with
The machinability was poor, and the incidence rate of edge chips was 35% when the compound of the following formula (V) was used, and 20% when the compound of the following formula (VI) was used. The oxygen permeability of the obtained contact lens is 8.6 × 10 ^-11 CC (STP) · cm / cm ² · sec · mmHg (25
℃), when using the compound of the following formula (VI) 9.7 × 10 ^-11
It was CC (STP) / cm / cm ² · sec · mmHg (25 ° C).

Comparative Examples 5 to 7 Contact was performed in the same manner as in Example 1 using 3.00 g of siloxanylalkyl methacrylate represented by the following formula (VII), the following formula (VIII) or the following formula (IX) and 7.00 g of methyl methacrylate. When a lens was manufactured, the machinability was poor, and the incidence of edge chips was 45% when the compound of the following formula (VII) was used, 50% when the compound of the following formula (VIII) was used, 10% when using the compound of the following formula (IX)
Met. The oxygen permeability of the obtained contact lens is
When a compound of the following formula (VII) is used, 1.5 × 10 ^-11 CC (S
TP) ・ cm / cm ²・ sec ・ mmHg (25 ℃), 1.0 × 10 ^-11 CC (STP) ・ cm / cm ²・ s when using the compound of the following formula (VIII)
It was ec · mmHg (25 ° C) and 0.5 × 10 ^-11 CC (STP) · cm / cm ² · sec · mmHg (25 ° C) when the compound of the following formula (IX) was used.

The effects of the present invention are clear from the above examples and comparative examples.

[Effect]

According to the present invention, oxygen permeability is superior to conventional ones,
Moreover, it is possible to provide a contact lens that can be industrially advantageously manufactured, and its industrial utility is extremely large.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Susumu Saito 1621 Sakata, Kurashiki City, Okayama Prefecture Kuraray Co., Ltd. (56) References JP-A-59-81320 (JP, A) JP-A-58-7124 (JP) , A) JP 58-132725 (JP, A) JP 50-87184 (JP, A)

Claims (4)

[Claims] 1. The following general formula (Wherein R ₁ is a hydrogen atom or a methyl group, l is 1 or 2 or 3, m is 1 or 2, and n is 3-m). To 80 parts by weight and at least one C 1-10 (meth) acrylic acid alkyl monoester of 80 to 20 parts by weight, obtained by polymerizing a monomer composition consisting essentially of Oxygen permeable contact lens consisting of a united body. 2. The contact lens according to claim 1, wherein R ₁ is a methyl group. 3. The contact lens according to claim 1 or 2, wherein l is 3. 4. The contact lens according to claim 1, which is obtained by further adding a crosslinking agent to the monomer composition and polymerizing.