JP2005215111A - Solution for hydrophilic contact lens - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a contact lens solution that makes the hydrophilicity of the surfaces of a contact lens improved. <P>SOLUTION: The contact lens solution contains partially deacetylated chitosan of 30 to 70% for the degree of deacetylation. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a contact lens solution, and in particular, the surface of an oxygen permeable contact lens such as an oxygen permeable hard contact lens, an oxygen permeable non-hydrated soft contact lens, or an oxygen permeable hydrated soft contact lens is made hydrophilic or surface-treated. The present invention relates to a contact lens solution that can be used as a surface hydrophilizing agent for maintaining the hydrophilicity of the liquid, and a hydrophilization method using the solution.

So far, oxygen permeable hard contact lenses mainly composed of siloxanyl methacrylate, fluoroalkyl methacrylate, methyl methacrylate, etc., polydimethylsiloxane macromer, siloxanyl methacrylate, fluoroalkyl methacrylate, hydroxyethyl methacrylate, dihydroxypropyl methacrylate, Provided are oxygen-permeable water-containing soft contact lenses mainly composed of n-vinylpyrrolidone and the like, and oxygen-permeable water-free soft contact lenses mainly composed of polydimethylsiloxane macromer, fluoroalkyl methacrylate, siloxanyl methacrylate and the like. The surface of these oxygen-permeable contact lenses is methyl methacrylate, hydroxyethyl methacrylate, dihydroxypropyl methacrylate. Compared to conventional contact lenses mainly composed of rate, n-vinyl pyrrolidone, etc., the hydrophilicity of the lens surface is weak, the tear film on the lens surface becomes unstable when worn, water repellency occurs, and cloudiness occurs Or increased adhesion of lipids, which sometimes causes problems that are difficult to see.
Therefore, as a method of hydrophilizing the surface of these oxygen permeable contact lenses, plasma surface treatment, chemical treatment with acid / alkali, etc., hydrophilization method by plasma polymerization treatment, etc. are considered, but hydrophilic durability, air Among them, there was a problem in stability when it became semi-dry, and it took time and effort to process again, and there was a problem in maintaining performance.

On the other hand, in Patent Document 1, a contact lens is immersed in a solution containing a hydrophilic polymer such as polyvinyl alcohol, hydroxyethyl cellulose, polyvinyl pyrrolidone, etc., and the polymer is attached to the surface of the contact lens to be hydrophilic. Patent Document 2 discloses a method of hydrophilizing a lens surface by treatment with a solution containing a polymer having an ionic charge opposite to that of the contact lens surface. Patent Document 3 discloses 2-hydroxy A method in which a contact lens is immersed in a water-insoluble polymer solution containing ethyl methacrylate as a main component and then contacted with water to adhere the polymer to the lens surface. Patent Document 4 discloses an aqueous solution of a hydrolyzate of chitosan. Discloses a method of immersing a contact lens.
However, with these methods, even if the treatment is simple, there is a problem that the degree of hydrophilicity is weak and the performance deteriorates with time during wearing, and the oxygen permeability of the contact lens becomes high, so that the lens material having a Dk value of 40 or more can be obtained. Has the disadvantage of little or no effect.

Japanese Patent Publication No. 48-37910 Japanese Examined Patent Publication No. 2-61017 Japanese Laid-Open Patent Publication No. 3-48811 JP-A-7-218878

  An object of the present invention is to provide a contact lens solution that is easy to operate, imparts very good hydrophilicity, and provides stable water wettability even when worn.

  The inventors of the present invention have made extensive studies, and as a result, a contact lens, particularly an oxygen permeable contact lens, can be applied to a solution containing partially deacetylated chitosan as a main component within a range of 30% to 70% deacetylation for a short time. It has been found that a very good hydrophilicity can be imparted to the surface of a contact lens by a simple operation of dipping, and a stable water wettability can be imparted even during wearing, and the present invention has been completed.

  The contact lens solution mainly composed of partially deacetylated chitosan within the range of 30% to 70% of the degree of deacetylation according to the present invention is an oxygen permeable hard contact lens, an oxygen permeable water-containing soft contact lens, an oxygen permeable A simple operation of immersing a contact lens such as a non-hydrated soft contact lens in the solution for a short time at room temperature makes the contact lens surface hydrophilic and improves the stability of the tear film on the lens surface when worn. It suppresses the occurrence of fogging, reduces the occurrence of cloudiness, suppresses adhesion of lipids, etc., and maintains the visibility.

Hereinafter, the present invention will be specifically described.
The present invention relates to a contact lens solution containing a partially deacetylated chitosan having a deacetylation degree of 30% to 70%.
Partially deacetylated chitosan having a degree of deacetylation in the range of 30% to 70% is a partially deacetylated chitosan soluble in water and having a degree of deacetylation by colloid titration in the range of 30% to 70%. It is.
From the viewpoint of high water solubility, the degree of deacetylation is preferably 30% to 70%. Further, it is preferably 30% or more from the viewpoint of facilitating a uniform solution, and preferably 70% or less from the viewpoint of improving the water wettability of the contact lens.
The degree of deacetylation is selected according to the contact lens to be treated in consideration of the affinity to the contact lens material, the hydrophilicity, the influence on the lens standard, and the like. In view of solubility in water and uniformity, the degree of deacetylation is more preferably in the range of 45% to 55%.

Furthermore, those having an average molecular weight of 1000 or more are preferred from the viewpoints of excellent sustainability of the hydrophilization performance, little influence on the contact lens, and no change in the shape and appearance of the contact lens, and the viscosity of the solution. From the viewpoint that handling property, liquid breakage from the container, etc. are in a practically appropriate range, those having an average molecular weight in the range of 3000 to 150,000 are particularly preferred.
Specific examples of these include those produced by partial deacetylation of chitin, those produced by partial acetylation of chitosan, and those obtained by hydrolyzing the obtained partially acetylated chitosan with acid or enzyme. Can be mentioned.
The production method of these partially deacetylated chitosan, the molecular weight, and the method of measuring characteristics such as the degree of deacetylation were cited in the “chitin and chitosan experiment manual” (Gihodo Publishing) and “chitin and chitosan experiment manual”. This is described in detail in Patent Document 5 (Japanese Patent Publication No. 56-33401).

The contact lens solution of the present invention contains at least one partially deacetylated chitosan having a degree of deacetylation in the range of 30% to 70%, depending on the material of the contact lens, the degree of hydrophilicity, and the durability performance. Two or more selected mixtures can be used.
The content of the partially deacetylated chitosan in the contact lens solution of the present invention can be appropriately selected according to the purpose of use of the solution, the viscosity of the solution, the type of contact lens, etc., but usually 5 to 0.0001% by weight. It is. For example, when used as a contact lens cleaner for processing in a short time, it is used at a high concentration of 5 to 0.01% by weight, and when a contact lens such as a contact lens storage solution is immersed for a long time, 1 to 0 is used. Used at low concentrations such as 0.0001% by weight.
The contact lens solution of the present invention is used by further adding a water-soluble chitin derivative modified with a glycol group such as carboxylmethyl group, hydroxyethyl group, hydroxypropyl group, glyceryl group, and polyglycol group. You can also

  In addition to making the contact lens surface hydrophilic, the contact lens solution of the present invention contains a surfactant having an action of washing the contact lens in order to remove the stain attached to the lens surface. It is also possible to contain more than one species. As surfactants, cationic surfactants, anionic surfactants, amphoteric surfactants, nonionic surfactants, etc. can be used, but amphoteric surfactants and nonionic surfactants can be used. The agent is preferable in that it does not change the shape of the contact lens. Examples of the zwitterionic surfactant include alkylbetaine type, and examples of the nonionic surfactant include polyoxyethylene polyoxypropylene glycol block. Examples thereof include copolymers, tetra (polyoxyalkylene) ethylenediamine, tetra (polyoxyethylenepolyoxypropylene) ethylenediamine, polyoxyethylene sorbitol, polyoxyethylene higher alkylate, and polyoxyethylene higher alkyl ether. These surfactants can be used in the range of 1 to 0.001% by weight depending on the purpose.

Moreover, it is also possible to add 1-0.0001 weight% of polyhydric alcohols which do not have influence on a contact lens, for example, glycerol, diglycerol, polyglycerol, sorbitol, dipropylene glycol, tripropylene glycol.
The present invention also relates to a method for making a lens surface hydrophilic by immersing the contact lens in the solution using a contact lens solution, and a contact lens for maintaining the hydrophilicity of the contact lens in the solution. A method of immersing a lens for storage and / or sterilization is provided.
The dipping time may be instantaneous dipping, but if it is 10 seconds or more, the effect of hydrophilization is greater, and it is usually preferable to dipping for 10 minutes or more.
When the contact lens solution of the present invention is used as a solution for preserving or disinfecting contact lenses, a viscosity-imparting base, buffer base, tonicity agent, preservative, antifungal agent, antibacterial agent, etc. are added. There is no problem. The additive concentration can be used in a wide range of concentrations known in the art.
The pH of the solution is preferably in the range that does not irritate the eyes, and is usually in the range of pH 6-8.

  The contact lens solution of the present invention can be applied to various contact lenses, but is suitable for oxygen-permeable hard contact lenses and oxygen-permeable soft contact lenses. Examples of materials for these contact lenses include methyl acrylate, Acrylic monomers such as ethyl acrylate and acrylic acid; methacrylic monomers such as methyl methacrylate, ethyl methacrylate, 2-hydroxyethyl methacrylate and methacrylic acid; tris (trimethylsiloxy) silylpropyl methacrylate, bis (trimethylsiloxy) methylsilylpropyl methacrylate, Pentamethyldisiloxanepropyl methacrylate, tris (trimethylsiloxy) silylpropyloxyethyl methacrylate, tris (polydimethylsiloxy) Siloxanyl monomers such as propylpropyl methacrylate; those having a hydrophilic group such as a urethane bond, glyceryl group or polyalkylene glycol group between the siloxanyl group and the methacrylate group, or a part of the siloxanyl group as a terminal hydroxy group or a polyalkylene glycol group A hydrophilic siloxanyl methacrylate substituted with a fluorosilicone monomer such as tris (dimethyltrifluoropropylsiloxy) silylpropyl methacrylate,

Perfluoroalkyl monomers such as 2,2,2-trifluoroethyl methacrylate, 2,2,3,3,3-pentafluoropropyl methacrylate, hexafluoroisopropyl methacrylate; 1,1,2,2-tetrafluoroethoxy- Fluoroalkyl and fluoroalkyl ether monomers having a hydroxyl group such as 2-hydroxypropyl methacrylate; hydrophilic monomers such as N-vinylpyrrolidone, N, N′-dimethylacrylamide, N, N′-vinylmethylacetamide; ethylene glycol di Crosslinkable monomers such as methacrylate, tetraethylene glycol dimethacrylate, and tetramethyldisiloxane bis (propyl methacrylate); siloxane macromers having a polymerizable unsaturated group at the molecular end of polydimethylsiloxane , And perfluoro modified macromer, modified siloxane macromer such as polyalkylene glycol modified macromer; copolymer of copolymerizable monomers and macromers, and the like. A combination of these monomers and macromers provides an oxygen permeable hard contact lens, an oxygen permeable non-hydrated soft contact lens, or an oxygen permeable hydrated soft contact lens.

Among these, siloxane-based methacrylate, fluoroalkylsiloxane-based methacrylate, fluoroalkyl-based methacrylate, fluoroalkyl ether-based methacrylate containing a hydroxyl group, because of a good balance of physical properties such as oxygen permeability, stain resistance, and mechanical strength, A copolymer such as a hydrophilic monomer, a crosslinkable monomer having two or more unsaturated groups in the molecule, or a siloxane macromer having a polymerizable unsaturated group at the molecular end is preferred.
The contact lens used in the present invention is produced from a polymer obtained by adding a polymerization initiator for initiating polymerization by heat, UV, electron beam or radiation to a mixture selected from the above monomers and macromers. Is done. Additives such as dyes and UV absorbers can be added depending on the purpose.

The contact lens used in the present invention is soluble in a mixture selected from the above monomers and macromers and further in a monomer mixture in order to control the microstructure and macrostructure of the polymer so as to meet the purpose of the present invention. A certain lower alcohol or water-soluble organic solvent can be added in the range of 0.2 to 50%. As these lower alcohols or organic solvents, methanol, ethanol, isopropyl alcohol, butyl alcohol, ethylene glycol, glycerin, dimethylacetamide, dimethylformamide, tetrahydrofuran, alkyl phosphate ester, pyrrolidone and the like can be used.
The above contact lens can be manufactured by a conventional lens manufacturing method, for example, a method in which a polymer block is cut by a lathe with a lathe or polished, or only one surface of a lens is cast and polymerized with a polymerization mold to form another surface. Can be produced by a method of finishing by cutting and polishing, a casting method in which a monomer composition is injected into a polymerization mold corresponding to the shape of a lens and polymerized. It is also possible to improve surface characteristics, particularly water wettability, by subjecting the lens surface to ozone treatment and plasma irradiation treatment after production by cast polymerization.

Next, the present invention will be described with reference to examples and reference examples. Unless otherwise stated, “%” represents “% by weight”.
The wettability of the contact lens evaluated in the examples was measured by the following method.
A contact lens immersed in or washed with a test solution was washed with tap water for 30 seconds, held vertically, immersed in 0.9% physiological saline, gently lifted, and attached to the lens after 30 seconds. Saline morphology was recorded with photographs. Evaluation was made according to the following criteria from the state of water adhering to the front curve surface (FC surface) of the lens.
Rank Degree of water wet 3: The entire lens surface (FC surface) is wet.
2: 2/3 of the lens is wet.
1: Half of the lens is wet.
0: The lens is not wet. (Water sticks in a ball shape)

[Example 1]
60 parts by weight of siloxanyl methacrylate, 20 parts by weight of trifluoromethyl methacrylate, 10 parts by weight of methyl methacrylate, 5 parts by weight of methacrylic acid, 5 parts by weight of ethylene glycol dimethacrylate, and azobisisobutyro as a polymerization initiator 700 ppm of nitrile was added, placed in a polypropylene test tube, polymerized by heating at 50 ° C. for 17 hours and at 60 ° C. for 14 hours, then heated at 80 ° C. for 24 hours and post-polymerized to obtain a diameter 14 It was cut into a shape with a thickness of 7 mm and a thickness of 5 mm. Next, a contact lens with a base curve of 7.7 mm, a diameter of 8.8 mm, a power of 3.00 diopter, and a center thickness of 0.17 mm was manufactured using a contact lens machining lathe. This contact lens had a water wettability of rank 0 and was inferior in water wettability. The contact lens was evaluated for 30 seconds after washing with 0.9% saline containing 1% chitosan (average molecular weight 37000) having a deacetylation degree of 38%. In the later evaluation, excellent water wettability was maintained at rank 3. The base curve of the lens was 7.69 mm, unchanged from the initial value.

[Example 2]
The contact lens produced in Example 1 was immersed in 0.9% physiological saline in which 0.03% of chitosan having a deacetylation degree of 38% (average molecular weight 37000) was dissolved, and the wettability of the contact lens after 3 days. Was ranked 3, and the evaluation after 2 months was also good at wetness at rank 3. The base curve of the lens was 7.7 mm, unchanged from the initial value, and the lens appearance was not abnormal.
[Example 3]
The contact lens prepared in Example 1 was prepared using 0.5% sodium chloride, 0.12% monosodium hydrogen phosphate, 0.15% dipotassium hydrogen phosphate, 0.1% EDTA-2 sodium, and a degree of deacetylation of 45. The water wettability of contact lenses after immersion for 3 hours in a stock solution in which 0.1% chitosan (average molecular weight of 10,000) is dissolved is rank 3, and excellent water wettability in rank 3 in the evaluation after 2 months. Was maintained. The base curve of the lens was 7.71 mm, unchanged from the initial value, and there was no dirt on the lens surface.

[Example 4]
The contact lens prepared in Example 1 is 0.5% sodium chloride, 0.12% monosodium hydrogen phosphate, 0.15% dipotassium hydrogen phosphate, 0.1% EDTA-2 sodium, 0.1% hydroxyethyl cellulose. In addition, the wettability of the contact lens after 1 day of treatment with a stock solution in which 45% of deacetylated chitosan (average molecular weight of 10000) is dissolved in 0.05% is rank 3, and the evaluation after 2 months is also rank 3. Excellent water wettability was maintained. The base curve of the lens was 7.74 mm, unchanged from the initial value, and there was no dirt on the surface.
[Example 5]
The contact lens prepared in Example 1 is made from 0.5% sodium chloride, 0.12% monosodium hydrogen phosphate, 0.15% dipotassium hydrogen phosphate, 0.1% EDTA-2 sodium, and a degree of deacetylation of 55. % (Average molecular weight 30000) of chitosan dissolved in a 0.5% stock solution The contact lens water wettability after 1 day is rank 3, and the water wettability of rank 3 is maintained in the evaluation after 2 months Was. The base curve of the lens was 7.71 mm, unchanged from the initial value, and there was no dirt on the surface.
[Comparative Example 1]
The contact lens manufactured in Example 1 was immersed for 3 hours in 0.9% physiological saline in which chitosan having a deacetylation degree of 85% (average molecular weight 30000) was solubilized with acetic acid and dissolved in 0.3%. The wettability was rank 1. The water wettability after 2 months of immersion was also unchanged at rank 1.

  The present invention has an effect of imparting water wettability to a contact lens, and is used to make the surface hydrophilic of a contact lens, particularly an oxygen-permeable hard contact lens, an oxygen-permeable water-containing soft contact lens, or an oxygen-permeable non-water-containing soft contact lens. It is suitable as a treatment solution and a preservation solution.

Claims (6)

  A contact lens solution comprising a partially deacetylated chitosan having a degree of deacetylation in the range of 30% to 70%.   The contact lens solution according to claim 1, wherein the partially deacetylated chitosan has an average molecular weight of 1000 or more.   A method for using a contact lens solution, wherein the contact lens solution according to claim 1 or 2 is used as a contact lens storage solution and / or a cleaning solution.   4. The method of using a contact lens solution according to claim 3, wherein the contact lens is an oxygen permeable hard lens or an oxygen permeable soft lens.   A method for hydrophilizing a contact lens surface, comprising contacting or immersing the contact lens in the contact lens solution according to claim 1 or 2 to improve the wettability of the contact lens.   6. The method for hydrophilizing a contact lens surface according to claim 5, wherein the contact lens is an oxygen permeable hard lens or an oxygen permeable soft lens.