JP3013439B2 - Method of manufacturing contact lenses - Google Patents
Method of manufacturing contact lensesInfo
- Publication number
- JP3013439B2 JP3013439B2 JP2321776A JP32177690A JP3013439B2 JP 3013439 B2 JP3013439 B2 JP 3013439B2 JP 2321776 A JP2321776 A JP 2321776A JP 32177690 A JP32177690 A JP 32177690A JP 3013439 B2 JP3013439 B2 JP 3013439B2
- Authority
- JP
- Japan
- Prior art keywords
- contact lens
- polymerization
- added
- lens
- water
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired - Lifetime
Links
Landscapes
- Eyeglasses (AREA)
- Addition Polymer Or Copolymer, Post-Treatments, Or Chemical Modifications (AREA)
- Macromonomer-Based Addition Polymer (AREA)
Description
【発明の詳細な説明】 ［産業上の利用分野］ 本発明はコンタクトレンズに関し、特に濡れ性と装用
感に優れるハードコンタクトレンズに関する。Description: TECHNICAL FIELD The present invention relates to a contact lens, and more particularly to a hard contact lens excellent in wettability and wearing feeling.
［従来の技術］ コンタクトレンズ装用時の異物感を減少させて装用感
を向上させるには、角膜とレンズ表面とのなじみを良く
することが重要である。具対的な方法としては、レンズ
表面に親水性モノマーであるアクリルアミドをグラフト
重合することにより、レンズ表面の濡れ性を向上させる
ことがあげられる。さらに、濡れ性を長期にわたって保
持するため、N,N′−メチレンビスアクリルアミドで架
橋してグラフト鎖の耐摩耗性を向上させる方法がある。[Related Art] In order to reduce the feeling of foreign matter when wearing a contact lens and to improve the wearing feeling, it is important to improve the familiarity 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 monomer, on the lens surface. Furthermore, in order to maintain the wettability over a long period of time, there is a method of improving the abrasion resistance of the graft chain by crosslinking with N, N'-methylenebisacrylamide.
グラフト重合を開始させるためには、コンタクトレン
ズ表面に放電処理などによって導入した過酸化物が分解
すること、すなわち過酸化物がラジカル重合の開始点と
して作用することが必要である。つまり重合を実行する
ためには、過酸化物分解に必要なエネルギーを供給しな
ければならない。In order to start the graft polymerization, it is necessary that the peroxide introduced into the contact lens surface by the discharge treatment or the like is decomposed, that is, the peroxide acts as a starting point of radical polymerization. That is, in order to carry out the polymerization, the energy required for peroxide decomposition must be supplied.
重合開始の手段には、放電処理後のコンタクトレンズ
を60℃〜90℃の高温中で加熱するという熱重合法や、触
媒を加えて30℃〜50℃の低温で行なうレドックス法があ
る。As a means for initiating the polymerization, there are a thermal polymerization method in which the contact lens after the discharge treatment is heated at a high temperature of 60 ° C to 90 ° C, and a redox method in which a catalyst is added at a low temperature of 30 ° C to 50 ° C.
従来、レドックス法においては、触媒として硫酸第一
鉄アンモニウム（モール塩）を制限なく添加していた。Conventionally, in the redox method, ammonium ferrous sulfate (Mole salt) has been added without limitation as a catalyst.
［発明が解決しようとする課題］ しかし、前述の従来技術では、添加量が少ないと長時
間反応させても重合が進まなかったり、グラフトポリマ
ーの重合度が大きくなりすぎてレンズの表面を白濁させ
てしまう。また、添加量が多すぎると重合の連鎖反応を
抑制し、重合が進まないという欠点を有していた。[Problems to be Solved by the Invention] However, in the above-mentioned conventional technology, if the addition amount is small, the polymerization does not proceed even if the reaction is performed for a long time, or the degree of polymerization of the graft polymer becomes too large, and the surface of the lens becomes cloudy. Would. On the other hand, if the addition amount is too large, the chain reaction of the polymerization is suppressed, and the polymerization does not proceed.
そこで本発明はこの問題点を解決するもので、その目
的とするところは、硫酸第一鉄アンモニウム（モール
塩）の添加量を制限することによって、低温でのグラフ
ト重合を可能にしながらも、レンズ表面が白濁しないよ
うなコンタクトレンズの製造方法を提供することにあ
る。Therefore, the present invention solves this problem, and the object of the present invention is to limit the amount of ammonium ferrous sulfate (Mole salt) to be added, thereby enabling low-temperature graft polymerization, An object of the present invention is to provide a method for manufacturing a contact lens in which the surface is not clouded.
［課題を解決するための手段］ 上記課題を解決するために本発明のコンタクトレンズ
の製造方法は、 （ａ）少なくとも、アルキルメタクリレートとシロキサ
ニルメタクリレート（ 式中ＸおよびＹはC1〜C5のアルキル基およびＺ基からな
る群から選ばれ、Ｚは構造式 をもつ基であり、ＡはC1〜C5のアルキル基を示す。m,n
は0,又は正の整数を示す。）との共重合物であるメタク
リル酸のエステル化合物のポリマーを原材料したコンタ
クトレンズにおいて、その表面を常圧あるいは減圧下で
放電処理する工程と、（ｂ）レンズ表面に親水性モノマ
ーをグラフト重合する工程とから成るコンタクトレンズ
の製造方法における、上記（ｂ）工程中の少なくともア
クリルアミド、N,N′−メチレンビスアクリルアミドお
よび水より成るモノマー水溶液に、水溶液中のモノマー
量1wt％に対し、硫酸第一鉄アンモニウム（モール塩）
を0.001mol添加することを特徴とする。[Means for Solving the Problems] In order to solve the above problems, the method for producing a contact lens according to the present invention comprises: (a) at least an alkyl methacrylate and a siloxanyl methacrylate ( Wherein X and Y are selected from the group consisting of C 1 -C 5 alkyl groups and Z groups; A group having, A is an alkyl group of C 1 -C 5. m, n
Represents 0 or a positive integer. A) subjecting a contact lens made of a polymer of an ester compound of methacrylic acid, which is a copolymer with (a), to a discharge treatment under normal pressure or reduced pressure, and (b) graft-polymerizing a hydrophilic monomer onto the lens surface In the method for producing a contact lens comprising the steps (a) and (b), a monomer aqueous solution comprising at least acrylamide, N, N'-methylenebisacrylamide and water is added to a monomer aqueous solution of 1 wt. Iron ammonium (mole salt)
Is added by 0.001 mol.
なお、代表的なメタクリル酸のエステル化合物には以
下のものがあげられる。The following are typical examples of methacrylic acid ester compounds.
ペンタメチルジシロキサニルメチルメタクリレート トリス（トリメチルシロキシ）−γ−メタクリルオキシ
プロピルシラン イソブチルヘキサメチルトリシロキサニルメチルメタク
リレート 以下、実施例により本発明の詳細を示す。Pentamethyldisiloxanylmethyl methacrylate Tris (trimethylsiloxy) -γ-methacryloxypropylsilane Isobutyl hexamethyltrisiloxanyl methyl methacrylate Hereinafter, the present invention will be described in detail with reference to examples.
［実施例１］ メチルメタクリレート60wt％、トリス（トリメチルシ
ロキシ）シリルプロピルメタクリレート35wt％、２−ヒ
ドロキシエチルメチクリレート5wt％の共重合物よりな
るコンタクトレンズを用意した。放電装置（電極間６セ
ンチメートル、電極間電圧270ボルト、周波数60ヘル
ツ）にレンズを設置して、0.04トールのアルゴン雰囲気
中で５秒間グロー放電処理をした後、レンズを空気中に
さらした。Example 1 A contact lens comprising a copolymer of 60% by weight of methyl methacrylate, 35% by weight of tris (trimethylsiloxy) silylpropyl methacrylate, and 5% by weight of 2-hydroxyethyl methacrylate was prepared. The lens was placed in a discharge device (6 cm between electrodes, voltage between electrodes 270 volts, frequency 60 Hz), glow-discharged in an argon atmosphere of 0.04 torr for 5 seconds, and then the lens was exposed to air.
モノマー水溶液は次のように調整した。まず、アクリ
ルアミド35gとN,N′−メチレンビスアクリルアミド5gを
秤量し、48gの水に溶解し、これをＡ液とした。The aqueous monomer solution was prepared as follows. First, 35 g of acrylamide and 5 g of N, N'-methylenebisacrylamide were weighed and dissolved in 48 g of water to obtain a liquid A.
また、硫酸第一鉄アンモニウム六水和物を1.568g（0.
04mol）秤量し、10gの水に溶解し、これをＢ液とした。In addition, 1.568 g of ferrous ammonium sulfate hexahydrate (0.
04 mol) was weighed and dissolved in 10 g of water to obtain a solution B.
Ａ液を2.4ml、Ｂ液を0.3mlを試験管に分取し、これに
水を0.3ml加えて重合溶液とした。このときの重合水溶
液の組成は、アクリルアミド35％、N,N′−メチレンビ
スアクリルアミド５％、水60％になり、硫酸第一鉄アン
モニウム（モール塩）の添加量は、0.004molすなわち水
溶液中のモノマー量1wt％に対し、0.001molになってい
る。2.4 ml of the solution A and 0.3 ml of the solution B were placed in a test tube, and 0.3 ml of water was added thereto to prepare a polymerization solution. At this time, the composition of the aqueous polymerization solution was 35% acrylamide, 5% N, N'-methylenebisacrylamide, and 60% water. The addition amount of ammonium ferrous sulfate (Mole salt) was 0.004 mol, that is, It is 0.001 mol per 1 wt% of the monomer.
試験管内のモノマー水溶液中に放電処理したレンズを
入れ、窒素ガス置換後、減圧封管した。試験管を35℃の
恒温槽中に50分置き、レンズ表面にモノマーをグラフト
重合した。こうして、全く同様な操作を施した６個の試
料（試料No.1〜６）を作成した。The discharge-treated lens was placed in a monomer aqueous solution in a test tube, and after nitrogen gas replacement, the tube was sealed under reduced pressure. The test tube was placed in a thermostat at 35 ° C. for 50 minutes, and a monomer was graft-polymerized on the lens surface. Thus, six samples (sample Nos. 1 to 6) subjected to completely the same operation were prepared.
また、従来法との比較のため、Ｂ液と水の割合を変え
た重合溶液でのグラフト重合試料を６個作製した（比較
例１〜６）。この時の放電条件や重合温度は上記の試料
（試料No.1〜６）と全く同様な操作を施した。Further, for comparison with the conventional method, six graft polymerization samples were prepared using a polymerization solution in which the ratio of the solution B to water was changed (Comparative Examples 1 to 6). The discharge conditions and polymerization temperature at this time were exactly the same as those of the above samples (samples Nos. 1 to 6).
引続き、グラフト処理後のレンズ表面の白濁を光学顕
微鏡で観察した。また、グラフト重合処理の完了を確認
するため、コンタクトレンズ表面の水濡れ性を液適法に
よる接触角で評価した。これらの結果を第１表に掲げ
る。Subsequently, the opacity of the lens surface after the grafting was observed with an optical microscope. Further, in order to confirm the completion of the graft polymerization treatment, the water wettability of the contact lens surface was evaluated by a contact angle by a liquid method. The results are listed in Table 1.
［実施例２］ メチルメタクリレート60wt％、トリス（トリメチルシ
ロキシ）シリルプロピルメタクリレート35wt％、２−ヒ
ドロキシエチルメチクリレート5wt％の共重合物よりな
るコンタクトレンズを用意した。電極間距離3.5センチ
メートル、電極間電圧15キロボルト、周波数60ヘルツの
コロナ放電処理装置の電極間に厚み1.5ミリメートルの
スペーサで作った空間にこのレンズを設置し、放電処理
をおこなった。尚、片面ずつ、両面に40秒ずつ放電処理
をした。 Example 2 A contact lens comprising a copolymer of methyl methacrylate 60 wt%, tris (trimethylsiloxy) silylpropyl methacrylate 35 wt%, and 2-hydroxyethyl methacrylate 5 wt% was prepared. This lens was placed in a space made of spacers with a thickness of 1.5 mm between electrodes of a corona discharge treatment device with a distance of 3.5 cm between electrodes, a voltage of 15 kV between electrodes, and a frequency of 60 Hz, and discharge treatment was performed. In addition, discharge treatment was performed on each side and each side for 40 seconds.
モノマー水溶液は次のように調整した。まず、アクリ
ルアミド35gとN,N′−メチレンビスアクリルアミド5gを
秤量し、48gの水に溶解し、これをＡ液とした。The aqueous monomer solution was prepared as follows. First, 35 g of acrylamide and 5 g of N, N'-methylenebisacrylamide were weighed and dissolved in 48 g of water to obtain a liquid A.
また、硫酸第一鉄アンモニウム六水和物を1.568g（0.
04mol）秤量し、10gの水に溶解し、これをＢ液とした。In addition, 1.568 g of ferrous ammonium sulfate hexahydrate (0.
04 mol) was weighed and dissolved in 10 g of water to obtain a solution B.
Ａ液を2.4ml、Ｂ液を0.3mlを試験管に分取し、これに
水を0.3ml加えて重合溶液とした。このときの重合水溶
液の組成は、アクリルアミド35％、N,N′−メチレンビ
スアクリルアミド５％、水60％になり、硫酸第一鉄アン
モニウム（モール塩）の添加量は、0.004molすなわち水
溶液中のモノマー量1wt％に対し、0.001molになってい
る。2.4 ml of the solution A and 0.3 ml of the solution B were placed in a test tube, and 0.3 ml of water was added thereto to prepare a polymerization solution. At this time, the composition of the aqueous polymerization solution was 35% acrylamide, 5% N, N'-methylenebisacrylamide, and 60% water. The addition amount of ammonium ferrous sulfate (Mole salt) was 0.004 mol, that is, It is 0.001 mol per 1 wt% of the monomer.
試験管内のモノマー水溶液中に放電処理したレンズを
入れ、窒素ガス置換後、減圧封管した。試験管を35℃の
恒温槽中に50分置き、レンズ表面にモノマーをグラフト
重合した。こうして、全く同様な操作を施した６個の試
料（試料No.1〜６）を作成した。The discharge-treated lens was placed in a monomer aqueous solution in a test tube, and after nitrogen gas replacement, the tube was sealed under reduced pressure. The test tube was placed in a thermostat at 35 ° C. for 50 minutes, and a monomer was graft-polymerized on the lens surface. Thus, six samples (sample Nos. 1 to 6) subjected to completely the same operation were prepared.
また、従来法との比較のため、Ｂ液と水の割合を変え
た重合溶液でのグラフト重合試料を６個作製した（比較
例１〜６）。この時の放電条件や重合温度は上記の試料
（試料No.1〜６）と全く同様な操作を施した。Further, for comparison with the conventional method, six graft polymerization samples were prepared using a polymerization solution in which the ratio of the solution B to water was changed (Comparative Examples 1 to 6). The discharge conditions and polymerization temperature at this time were exactly the same as those of the above samples (samples Nos. 1 to 6).
引続き、グラフト処理後のレンズ表面の白濁を光学顕
微鏡で観察した。また、グラフト重合処理の完了を確認
するため、コンタクトレンズ表面の水濡れ性を液適法に
よる接触角で評価した。これらの結果を第２表に掲げ
る。Subsequently, the opacity of the lens surface after the grafting was observed with an optical microscope. Further, in order to confirm the completion of the graft polymerization treatment, the water wettability of the contact lens surface was evaluated by a contact angle by a liquid method. Table 2 shows the results.
第１表および第２表より明かな如く、試料No.1〜６は
表面白濁が全く生じていなかった。また、接触角は50゜
以下となり、これは、グラフト重合が支障なく進んだこ
とを示すものである。 As is clear from Tables 1 and 2, samples Nos. 1 to 6 had no surface turbidity. Further, the contact angle was 50 ° or less, which indicates that the graft polymerization proceeded without hindrance.
これに対し、モール塩添加量の少ないもの（比較例２
〜４）は接触角は充分低下しており、グラフト重合処理
は完了した。しかし、表面白濁が生じ、表面処理として
はふさわしくない。また、モール塩添加量が多いもの
（比較例５〜６）は接触角が高く、これはグラフト重合
が進まなかったことを示している。なお、比較例１のよ
うにモル塩を添加しないものについては、いうまでもな
く集合は進行していない。On the other hand, those with a small amount of Mohr salt added (Comparative Example 2
In Nos. To 4), the contact angle was sufficiently reduced, and the graft polymerization treatment was completed. However, surface turbidity occurs, which is not suitable for surface treatment. In addition, those with a large amount of Mohr salt added (Comparative Examples 5 to 6) had a high contact angle, which indicates that the graft polymerization did not proceed. In addition, as for Comparative Example 1 in which no molar salt is added, it goes without saying that aggregation does not proceed.
本発明の実施例をSi系PMMA製コンタクトレンズとを用
いて説明してきたがこれに限ることなく、その他のハー
ドコンタクトレンズや、シリコンラバーなどのソフトコ
ンタクトレンズについても同様な結果を得ている。Although the embodiment of the present invention has been described using a Si-based PMMA contact lens, the present invention is not limited to this, and similar results are obtained with other hard contact lenses and soft contact lenses such as silicon rubber.
さらに、ポリエチレンフィルム、ポリプロピレン、ポ
リ塩化ビニル、ポリ塩化ビニリデン、アセテート、ポリ
エステル、ポリビニルアルコール、ポリスチレン、ポリ
カーボネート、その他様々なプラスチックフィルムの表
面処理に対しても同様な結果が得られた。Further, similar results were obtained for surface treatment of polyethylene films, polypropylene, polyvinyl chloride, polyvinylidene chloride, acetate, polyester, polyvinyl alcohol, polystyrene, polycarbonate, and various other plastic films.
くわえて、上にあげた樹脂を使用した各種包装材、農
業用保水材、または人工臓器などの医療用製品にも応用
が可能である。In addition, it can be applied to various packaging materials using the above-mentioned resins, agricultural water retention materials, and medical products such as artificial organs.
［発明の効果］ 以上述べたように、発明によれば、少なくともアクリ
ルアミド、N,N′−メチレンビスアクリルアミドおよび
水より成るモノマー水溶液に硫酸第一鉄アンモニウム
（モール塩）を適当量添加することにより、表面白濁の
無い、低温グラフト処理が可能になった。これは、歩留
まりの向上、さらには高温という苛酷な処理条件により
レンズを解放できるという効果を有する。従って、本発
明はたいへん有効な方法であるといえ、そのもたらす効
果は多大である。[Effects of the Invention] As described above, according to the invention, by adding an appropriate amount of ammonium ferrous sulfate (mole salt) to a monomer aqueous solution comprising at least acrylamide, N, N'-methylenebisacrylamide and water. Low-temperature grafting without surface turbidity became possible. This has the effect of improving the yield and releasing the lens under severe processing conditions such as high temperature. Therefore, although the present invention is a very effective method, its effect is great.
Claims (1)
トとシロキサニルメタクリレート（ 式中ＸおよびＹはC1〜C5のアルキル基およびＺ基からな
る群から選ばれ、Ｚは構造式 をもつ基であり、ＡはC1〜C5のアルキル基を示す。m,n
は0,又は正の整数を示す。）との共重合物であるメタク
リル酸のエステル化合物のポリマーを原材料したコンタ
クトレンズにおいて、その表面を常圧あるいは減圧下で
放電処理する工程と、（ｂ）レンズ表面に親水性モノマ
ーをグラフト重合する工程とから成るコンタクトレンズ
の製造方法における、上記（ｂ）工程中の少なくともア
クリルアミド、N,N′−メチレンビスアクリルアミドお
よび水より成るモノマー水溶液に、水溶液中のモノマー
量1wt％に対し、硫酸第一鉄アンモニウム（モール塩）
を0.001mol添加することを特徴とするコンタクトレンズ
の製造方法。(1) At least (a) an alkyl methacrylate and a siloxanyl methacrylate ( Wherein X and Y are selected from the group consisting of C 1 -C 5 alkyl groups and Z groups; A group having, A is an alkyl group of C 1 -C 5. m, n
Represents 0 or a positive integer. A) subjecting a contact lens made of a polymer of an ester compound of methacrylic acid, which is a copolymer with (a), to a discharge treatment under normal pressure or reduced pressure, and (b) graft-polymerizing a hydrophilic monomer onto the lens surface In the method for producing a contact lens comprising the steps (a) and (b), a monomer aqueous solution comprising at least acrylamide, N, N'-methylenebisacrylamide and water is added to a monomer aqueous solution of 1 wt. Iron ammonium (mole salt)
Of a contact lens, characterized in that 0.001 mol of is added.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP2321776A JP3013439B2 (en) | 1990-11-26 | 1990-11-26 | Method of manufacturing contact lenses |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP2321776A JP3013439B2 (en) | 1990-11-26 | 1990-11-26 | Method of manufacturing contact lenses |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPH04190320A JPH04190320A (en) | 1992-07-08 |
| JP3013439B2 true JP3013439B2 (en) | 2000-02-28 |
Family
ID=18136303
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP2321776A Expired - Lifetime JP3013439B2 (en) | 1990-11-26 | 1990-11-26 | Method of manufacturing contact lenses |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JP3013439B2 (en) |
Families Citing this family (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US5391589A (en) * | 1991-12-10 | 1995-02-21 | Seiko Epson Corporation | Contact lens and method of producing a contact lens |
| WO1995017689A1 (en) * | 1993-12-21 | 1995-06-29 | Bausch & Lomb Incorporated | Method for increasing hydrophilicity of contact lenses |
| JP4103175B2 (en) * | 1998-05-20 | 2008-06-18 | 東レ株式会社 | Production method of polymer for ophthalmic lens |
-
1990
- 1990-11-26 JP JP2321776A patent/JP3013439B2/en not_active Expired - Lifetime
Also Published As
| Publication number | Publication date |
|---|---|
| JPH04190320A (en) | 1992-07-08 |
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