Methods of inhibiting the adherence of lenses to their packaging

This application is a Continuation-In-Part application of U.S. application Ser. No. 09/731,553, filed Dec. 7, 2000, now granted as U.S. Pat. No. 6,531,432.

This invention related to packaging solutions for use with contact lenses and methods for their use.

Contact lenses have been used commercially to improve vision since the 1950s. The first contact lenses were made of hard materials. Although these lenses are currently used, they are not suitable for all patients due to their poor initial comfort. Later developments in the field gave rise to soft contact lenses, based upon hydrogels, which are extremely popular today. These lenses have higher oxygen permeabilities and such are often more comfortable to wear than contact lenses made of hard materials. However, these new lenses are not without problems.

Contact lenses with high oxygen permeabilites are typically made of hydrophobic materials. The packaging for contact lenses are also made of hydrophobic materials. When one hydrophobic surface comes in contact with another, the surfaces stick to each other. The sticking of a contact lens to its packaging creates many problems. First the packaging is thicker and more rigid than the soft lenses contained therein. If a lens sticks to the packaging, when the user tries to remove the lens, the lens often tears and must be discarded. One solution to this problem is to place a hydrophilic additive such as a surfactant, into the lens packaging solution. However many surfactants that have been used to solve this problem do not prevent the sticking of contact lenses to their packaging. In addition, some surfactants do not completely dissolve in lens packaging solutions and have unfavorable interactions with the lens when they are stored over a period of time, Therefore there is a need for methods of inhibiting the adherence of contact lenses to their packaging. It is this need that is met by the following invention.

This invention includes a method of inhibiting the adherence of soft lenses to hydrophobic packaging materials comprising, consisting essentially of, or consisting of storing the soft lenses in a packing solution comprising an effective amount of composition of Formula I

wherein

R 1 is C 1-6 alkyl;, R 2 is —CH 2 OH, —CH 2 OR 3 , —CH 2 OC(O)R 4

wherein R 3 is C 1-50 alkyl, or C 1-51 alkylene having at least one double bond, R 4 is hydrogen or C 1-12 alkyl;

R 5 is —OH, or —[(O—(CHR 7 ) a ) n —OR 6 ]

wherein R 6 is hydrogen C 1-50 alkyl, or C 1-51 alkylene having at least one double bond, R 7 is hydrogen or C 1-12 alkyl;

R 8 is —OH or —[(O—(CHR 10 ) b ) m —OR 9 ]

wherein R 9 is hydrogen, C 1-50 alkyl, or C 1-51 alkylene having at least one double bond R 10 is hydrogen or C 1-12 alkyl;

R 11 is —OH or —OC(O)R 12

wherein R 12 is C 1-50 alkyl or C 1-51 alkylene having at least one double bond;

a is 2-4; b is 2-4; x is 0-3; q is 0-3; z is 0-3

wherein the sum of x+q+z=3

m is an integer, from 1 to 200; n is an integer from 1 to 200 wherein the sum of m+n=2 to 400

provided that if q is 3 R 6 is not ethyl; provided that if z is 3 R 9 is not ethyl.

With respect to Formula I, all substituents are selected independent of one another. The term alkyl refers to straight or branched alkyl chains. Alkylene refers to a carbon radical having at least one point of unsaturation. The preferred values for the substituents are as follows:

R 1 is methyl, ethyl or propyl, R 2 is —CH 2 OC(O)R 4 , R 3 is C 10-18 alkyl, R 4 is C 8-30 alkyl, or C 10-30 alkylene having at least one double bond, R 5 is —[(O—(CHR 7 ) a ) n —OR 6 ], R 6 is C 8-30 alkyl, or C 10-30 alkylene having at least one double bond, R 7 is hydrogen, R 8 is —[(O—(CHR 10 ) b ) m —OR 9 ] R 9 is C 8-30 alkyl, or C 10-30 alkylene having at least one double bond, R 10 is hydrogen, R 11 is OC(O)R 12 , R 12 is C 8-30 alkyl or C 10-30 alkylene having at least one double bond, a is 2-3, b is 2-3, x is 1, q is 1, z is 1, m is 60-140 n is 80-120,

wherein the preferred sum of m+n is about 100-200.

Examples of suitable compositions of Formula I include but are not limited to CAS No. 119831-19-5, 223717-75-7, and 116057-48-8.

The most particularly preferred composition of Formula I is poly(oxy-1,2-ethandiyl) α-hydro-ω-hydroxy-, ether with methyl D-glucopyranoside 2,6-di-9Z-9-octadecenaoate, commercially known as Glucamate DOE 120.

The compositions of Formula I may be combined with any known active or carrier components useful for lens packing solutions. Suitable additional ingredients include but are not limited to antibacterial agents, anti-dryness agents, such a polyvinyl alcohol, polyvinyl pyrrolidone, and dextran, tonicity agents, and combinations thereof.

The packing solutions of the invention may be any water-based solution that is used for the storage of contact lenses. Typical solutions include, without limitation, saline solutions, other buffered solutions, and deionized water. The preferred aqueous solution is saline solution containing salts including, without limitation, sodium chloride, sodium borate, sodium phosphate, sodium hydrogenphosphate, sodium dihydrogenphosphate, or the corresponding potassium salts of the same. These ingredients are generally combined to form buffered solutions that include an acid and its conjugate base, so that addition of acids and bases cause only a relatively small change in pH. The buffered solutions may additionally include 2-(N-morpholino)ethanesulfonic acid (MES), sodium hydroxide, 2,2-bis(hydroxymethyl)-2,2′, 2″-nitrilotriethanol, n-tris(hydroxymethyl)methyl-2-aminoethanesulfonic acid, citric acid, sodium citrate, sodium carbonate, sodium bicarbonate, acetic acid, sodium acetate, ethylenediamine tetraacetic acid and the like and combinations thereof. Preferably, the solution is a borate buffered or phosphate buffered saline solution.

As used herein “soft lenses” refers to an ophthalmic devices that resides in or on the eye. These devices can provide optical correction or may be cosmetic. The term lens includes but is not limited to soft contact lenses, intraocular lenses, overlay lenses, ocular inserts, and optical inserts. The preferred lenses of the invention are soft contact lenses are made from silicone elastomers or hydrogels, which include but are not limited to silicone hydrogels, and fluorohydrogels. Soft contact lens formulations are disclosed in U.S. Pat. No. 5,710,302, WO 9421698, EP 406161, JP 2000016905, U.S. Pat. No. 5,998,498, U.S. patent application Ser. No. 09/532,943, U.S. Pat. No. 6,087,415, U.S. Pat. No. 5,760,100, U.S. Pat. No. 5,776,999, U.S. Pat. No. 5,789,461, U.S. Pat. No. 5,849,811, and U.S. Pat. No. 5,965,631. The foregoing references are hereby incorporated by reference in their entirety. The particularly preferred lenses of the inventions are etafilcon A, genfilcon A, lenefilcon A, and polymacon. The most preferred lenses include but are not limited to silicone hydrogels such as acquafilcon A, balafilcon A, lotrafilcon A, and silicone hydrogels as prepared in U.S. Pat. No. 5,998,498, U.S. patent application Ser. No. 09/532,943, a continuation-in-part of U.S. patent application Ser. No. 09/532,943, filed on Aug. 30, 2000, U.S. Pat. No. 6,087,415, U.S. Pat. No. 5,760,100, U.S. Pat. No. 5,776,999, U.S. Pat. No. 5,789,461, U.S. Pat. No. 5,849,811, and U.S. Pat. No. 5,965,631. These patents as well as all other patents disclosed in this application are hereby incorporated by reference in their entirety.

“Hydrophobic packaging materials,” refer to substances that are used to prepare containers for manufacturing lenses prior to their use by an end user. These packaging materials are discarded by the user after the soft contact lens is placed in the eye of a user. Examples of hydrophobic packaging materials include but are not limited to polypropylene, polyethylene, nylons, olefin co-polymers, acrylics, rubbers, urethanes, polycarbonates, or fluorocarbons. The preferred materials are metallocenes polymers and co-polymers made of polypropylene, polyethylene, having a melt flow range of about 15 g/10 minutes to about 44 g/10 minutes as determined by ASTM D-1238. Containers made from hydrophobic packaging material may be in many forms. These containers may store a single lenses or many lenses. An example of a single lens storage unit is a blister package, such as the packages disclosed in the following publications, U.S. Pat. Nos. D435,966 S; 4,691,820; 5,467,868; 5,704,468; 5,823,327; 6,050,398, which are hereby incorporated by reference in their entirety. Examples of multiple lens storage units include the hydrophobic molds that are used to produce contact lenses as shown in U.S. Pat. No. 4,640,489 which is hereby incorporated in reference in its entirety.

The term “effective amount” refers to the percentage of weight of compositions of Formula I that will inhibit the adherence of lenses to hydrophobic packaging. The effective amount is about 0.01 weight percent to about 2.0 weight percent, preferably about 0.05 weight percent to about 1.50 weight percent, more preferably about 0.05 to about 0.1 weight percent.

In order to illustrate the invention the following examples are included. These examples do not limit the invention. They are meant only to suggest a method of practicing the invention. Those knowledgeable in contact lenses as well as other specialties may find other methods of practicing the invention. However, those methods are deemed to be within the scope of this invention.

The following abbreviations are used in the examples below:

Lens Preparation

Lenses A

Monomer mix is prepared by blending 18.16 weight percent of GTP(Macromer 2), 28.29% mPDMS, 14.14% TRIS, 26.27% DMA, 5.05% HEMA, 5.05% PVP (360,000 molecular weight), 2.02% Norbloc, 0.02% Blue HEMA, 1% CGI 1850, in a blend with 79.84 parts of this combination with 20.16 parts D30 diluent and CYST 0.4%. Contact lenses were made by placing this monomer mix into thermoplastic contact lens molds, and irradiating using Philips TL20W/03T fluorescent bulbs at 70° C. for about 15 minutes. The molds were opened and lenses were extracted into DPMA solvent. The lenses were then rinsed in a 100 ppm Tween 80 in DI mixture to insure removal of solvent. The lenses were then equlibrated in deionized water.

Lenses B

Monomer mix is prepared by blending 17.98 weight percent of GTP(Macromer 2), 28% mPDMS, 14% TRIS, 26% DMA, 5% HEMA, 5% PVP, 2% Norbloc, 1% TEGDMA, 0.02% Blue HEMA,1% CGI 1850, in a blend with 80 parts of this combination with 20 parts D3O diluent and CYST 0.2%. Lenses were made in the same manner as Lenses A with the exception that lenses were extracted in IPA. Lenses were then placed into deionized water for equilibration.

Lenses C

Monomer mix is prepared by blending 17.98 weight percent of GTP(Macromer 2), 28% mPDMS, 14% TRIS, 26% DMA, 5% HEMA, 5% PVP, 2% Norbloc, 1% TEGDMA, 0.02% Blue HEMA, 1% CGI 1850, in a blend with 80 parts of this combination with 20 parts D3O diluent. Lenses were made in the same manner as Lenses A.

Lenses D

Monomer mix is prepared by blending 17.98 weight percent of GTP(Macromer 2), 28% mPDMS, 14% TRIS, 26% DMA, 5% HEMA, 5% PVP (360,000 molecular weight), 2% Norbloc, 1% TEGDMA, 0.02% Blue HEMA, 1% CGI 1850, in a blend with 80 parts of this combination with 20 parts D3O diluent. Lenses were made in the same manner as Lenses A, with the exception that the lens molds had a pHEMA(big blue) coating on the surface as per the method disclosed in U.S. patent application Ser. No. 09/921,192 entitled “Method for Correcting Articles by Mold Transfer,” and that they were equilibrated into packing solution.

Lenses E

Monomer mix is prepared by blending 18.16 weight percent of GTP(Macromer 2), 28.29% mPDMS, 14.14% TRIS, 26.27% DMA, 5.05% HEMA, 5.05% PVP (360,000 molecular weight), 2.02% Norbloc, 0.02% Blue HEMA,1% CGI 1850, in a blend with 79.84 parts of this combination with 20.16 parts D3O diluent and CYST 0.4 Lenses were made in the same manner as Lenses A, with the exception that the lens molds had a pHEMA (big Blue) coating on the surface.

Lenses F

Lenses A were placed in a 10% silver nitrate solution for 60 minutes at room temperature for silver treatment. The lenses were then washed 3 times with DI water in 20 minute intervals to remove any excess silver. The lenses were then equilibrated in borate buffered saline.

Lenses G

Lenses B were placed in a 10% silver nitrate solution for 60 minutes at room temperature for silver treatment. The lenses were then washed 3 times with DI water in 20 minute intervals to remove any excess silver. The lenses were then equilibrated in borate buffered saline.

Lenses H

Lenses E were placed in a 10% silver nitrate solution for 60 minutes at room temperature for silver treatment. The lenses were then washed 3 times with DI water in 20 minute intervals to remove any excess silver. The lenses were then equilibrated in borate buffered saline.

Solution A

Solution A was made by adding 0.10 weight % of sodium borate, 0.91 weight % Boric Acid, 0.83% Sodium Chloride, 0.01% EDTA and 98.15 weight % water into a volumetric flask and was mixed at ambient temperature until all solids were dissolved. Solution A has a pH of 7.6 (measured at 20-30° C.), an osmolality of 170 (measured at ca. 25° C.) and a conductivity (m/S/cm) of 0.7 (measured at 20-30° C.)

Solution B

A solution was made by adding 0.185 weight % of sodium borate, 0.926 weight % Boric Acid and 98.89 weight % water into a volumetric flask and was mixed at ambient temperature until all solids were dissolved. Solution B has a pH of 7.0-7.6 (measured at 20-30° C.), an osmolality of 420 (measured at ca. 25° C.) and a conductivity (m/S/cm) of 14.5-15.5 (measured at 20-30° C.).

Solution C

Pure Vision Packing Solution removed from packaged commercially available Pure Vision Lenses.