WO1994021773A1

WO1994021773A1 - Alcohol-containing composition for cleaning contact lenses

Info

Publication number: WO1994021773A1
Application number: PCT/US1994/002545
Authority: WO
Inventors: Chimpiramma Potini; Stanley J. Wrobel
Original assignee: Polymer Technology Corporation
Priority date: 1993-03-18
Filing date: 1994-03-10
Publication date: 1994-09-29
Also published as: AU6400494A

Abstract

An aqueous composition for cleaning contact lenses comprises an anionic surface active agent and an aliphatic monohydric alcohol.

Description

ALCOHOL-CONTAINING COMPOSITION FOR CLEANING CONTACT

LENSES

BACKGROUND OF THE INVENTION

This invention relates to a composition for cleaning contact lenses. The composition comprises an anionic surface active agent and an aliphatic monohydric alcohol.

The tendency of contact lens materials to form deposits necessitates regular cleaning of the contact lenses. Deposits from the tear film include protein, lipid and mucin, and deposits from external sources include cosmetic deposits, such as from mascara or hair spray, or materials deposited when the lens is handled.

Enzymatic contact lens cleaners are frequently used to remove protein deposits, especially denatured proteins, particularly with hydrophilic soft contact lenses for which protein is the major deposit problem. However, enzymatic cleaners are not particularly effective for other types of deposits.

Surfactant contact lens cleaners, which employ a surface active agent having cleaning action, are used to remove lipid deposits, loosely bound protein deposits, and other deposits. Surfactant cleaners are used in conjunction with finger rubbing or other echanical cleaning, followed by rinsing to remove the deposits. Surfactant cleaners are used for hard and soft contact lenses. Hard lenses include polymethylmethacrylate lenses and rigid gas permeable lenses formed of a silicon acrylate or a fluorosilicon acrylate polymer. Soft lenses include hydrophilic hydrogel lenses.

An alcohol-containing commercial cleaner marketed by CIBA Vision (Atlanta, Georgia, USA) as an "extra- strength" contact lens cleaner is MiraFlow* Extra- Strength Daily Cleaner. This cleaner includes, as principal active ingredients: isopropanol; poloxamer 407 (a polyoxyethylene, polyoxypropylene block copolymer such as available under the trade name Pluronic F-127) ; and an amphoteric imidazole surfactant. Similar compositions are disclosed in U.S. Patent No. 4,046,706 (Krezanoski) .

U.S. Patent No. 4,421,665 (Lloyd et al.) discloses contact lens cleaning solutions comprising: a non- polar solvent in the form of cyclohexane and/or ethyl acetate, and optionally trace amounts of chloroform; ethanol or isopropanol as a polar solvent; and a surfactant. The surfactant is preferably a nonionic surfactant, although dioctylsulfosuccinate is also disclosed. The patent discloses that the non-polar solvent is adapted to provide for enhanced solubility of lipids and lipoproteins, and the alcohol has the ability to dissolve fully the non-polar solvents and potentiate their anti-microbial activity. However, the use of non-polar solvents such as cyclohexane, ethyl acetate, and chloroform in a contact lens solution is undesirable in case the composition is not adequately rinsed from the lens.

A challenge is to develop alcohol-containing contact lens cleaning compositions which not only provide the desired cleaning efficacy, but which also are suitable for ophthalmic use and are less damaging to the lenses. Efforts to develop alcohol-containing contact lens cleaning compositions often lead to compositions which damage the lens; for example, use of the compositions in a cleaning regimen may result in scratching of the lens surfaces, or deterioration of the lens such that the power of the lens is changed.

SUMMARY OF THE INVENTION

This invention provides an aqueous composition for cleaning contact lenses which comprises an aliphatic monohydric alcohol and an anionic surface active agent, and excludes nonpolar solvents such as cyclohexane, ethyl acetate and chloroform. Additionally, the invention relates to methods of cleaning contact lenses which employ the composition.

The alcohol-containing compositions provide the desired cleaning activity, yet are less damaging to lenses than the known commercial alcohol-containing cleaner. Additionally, the compositions achieve the desired cleaning efficacy without the use of cyclohexane, ethyl acetate and chloroform, or any other nonpolar solvent, which if not adequately rinsed from the lens, may be harmful or even toxic upon absorption by the skin or cornea.

DETAILED DESCRIPTION OF THE INVENTION The cleaning composition of the invention is an aqueous composition which includes an aliphatic monohydric alcohol. Preferred alcohols include C2-C₆ monohydric alkanols, with ethanol and isopropanol being especially preferred. The alcohol component is preferably present in the composition at about 5 to about 40 weight percent in order to provide adequate cleaning efficacy. According to preferred embodiments, the alcohol component is employed at about 7.5 to about 20 weight percent, and more preferably at about 7.5 to about 15 weight percent.

The composition also includes an anionic surface active agent. As used herein, the term "anionic surface active agent" means materials having cleaning action for contact lens deposits which ionize in water and possess the active part of the molecule in the anion. (While amphoteric surfactants may be either positively or negatively charged, depending on the pH environ ent, it is understood that the term "anionic surface active agent" does not include materials generally recognized as amphoteric surfactants.) Representative anionic surface active agents include εulfated and sulfonated surface active agents, and physiologically acceptable salts thereof, which provide good cleaning activity for lipids, proteins, and other contact lens deposits. Such anionic surface active agents may be represented by the general formulae:

ROS0₃"M (I) and RSO₃-M (II)

wherein: R is an organic radical including a C5-C2₀ alkyl or alkenyl group; and M is selected from the group consisting of H and physiologically acceptable salts such as Na⁺, IC^1", NH₄ ⁺, 1/2 Mg⁺ and (CH₂CH₂OH)3-NH⁺.

More specifically, the anionic surface active agent includes materials represented by the following general formula:

R¹(OCH₂CH₂)_nOSθ₃~M (III) wherein: R¹ is selected from the group consisting of C5-C2₀ alkyl and alkenyl; n has a value in the range of 0 to 10; and M is selected from the group consisting of H and physiologically acceptable salts such as Na^÷, IC^1", NH₄ ⁺, 1/2 Mg⁺ and (CH₂CH₂OH)₃NH⁺. Examples include sodium lauryl sulfate, sodium laureth sulfate (sodium εalt of sulfated ethoxylated lauryl alcohol) , ammonium laureth sulfate (ammonium salt of sulfated ethoxylated lauryl alcohol) , sodium cetyl sulfate, sodium octyl sulfate, sodium tridecyl sulfate, sodium trideceth sulfate (sodium salt of sulfated ethoxylated tridecyl alcohol) , triethanolamine lauryl sulfate, and magnesium lauryl sulfate.

Other anionic surface active agents include materials represented by the following general formulae:

O II

R²-C Y CH₂CH₂S0₃-M (IV)

R³ C₆H₄ S0₃"M (V)

wherein each of R² and R³ is selected from the group consisting of C5-C2₀ alkyl and alkenyl; Y is selected from the group consisting of -O- and -N(CH₃)-; and M is selected from the group consisting of H and physiologically acceptable salts such as Na⁺, IC^1", NH₄ ⁺, 1/2 Mg⁺ and (CH CH₂OH)sNH^"1". Examples include sodium methyl cocoyl taurate (sodium salt of the coconut fatty acid amide of N-methyltaurine) , sodium methyl oleoyl taurate (sodium salt of the oleic acid amide of N- methyltaurine) , and sodium dodecylbenzene sulfonate.

Further anionic surface active agents include materials represented by the following general for ulae:

R⁴ 0

R⁵-(-X-)p (CH₂C ¹H0)_q-»CCHS0₃~M (VI)

CH C-0~M

II o

o

wherein R⁴ is selected from the group consisting of H and methyl; each of R⁵, R⁶ and R⁷ is selected from the group consisting of Cg-C₂o alkyl and alkenyl; -X- is selected from the group consisting of -O- and -CONH-; p is 0 or 1; q has a value within the range of l to 6; and each M is independently selected from the group consisting of H and physiologically acceptable salts such as Na⁺, K+, NH₄ ⁺, 1/2 Mg⁺ and (CH₂CH₂OH)₃NH+. Examples include disodium lauryl sulfosuccinate (disodium salt of a lauryl alcohol half ester of sulfosuccinic acid) , disodium lauramido MEA- sulfosuccinate (disodium salt of a lauryl-substituted monoethanola ide half ester of sulfosuccinic acid) , disodium laureth sulfosuccinate (disodium salt of an ethoxylated lauryl alcohol half ester of sulfosuccinic acid) , disodium oleamido MEA-sulfosuccinate (disodium salt of an oleyl-substituted monoethanolamide half ester of sulfosuccinic acid) , disodium oleamido MIPA- sulfosuccinate (disodium salt of an oleyl-substituted isopropanolamide half ester of sulfosuccinic acid) , and dioctyl sodium sulfosuccinate (sodium salt of the diester of a 2-ethylhexyl alcohol and sulfosuccinic acid) .

Commercially available anionic surface active agents include those available under the following tradenames: Tauranol WS (sodium methyl cocoyl taurate, available from Finetex, Inc., El wood Park, New Jersey, USA) ; Varsulf SBFA-30 (C₁₂-C₁₄ fatty alcohol ethoxylated sulfosuccinate, available from Sherex Chemical Co., Dublin, Ohio, USA); Standapol SCH-101 (a mixture including disodium oleamido sulfosuccinate and sodium lauryl sulfate, available from Henkel, Inc., Hoboken, New Jersey, USA) ; Steol-7N (sodium laureth sulfate, available from Stepan Chemical Co. Surfactant Dept., Northfield, Illinois, USA); Sipex EST-30 (sodium trideceth sulfate, available from Rhone-Poulenc, Cranbury, New Jersey, USA) ; products available under the tradename Bio Soft which include sodium dodecylbenzene sulfonate (available from Stepan Chemical Co.); and Surfine WNT-A (sodium pareth-25-7- carboxylate, available from Finetex, Inc.). Other suitable anionic surface active agents would be evident to one skilled in the art. The composition may include one or more anionic surface active agents, preferably at about 0.1 to about 30 weight percent. Generally, smaller amounts of the anionic surface active agent may not provide adequate cleaning efficacy for certain deposits, whereas larger amounts of this component may make rinsing of lenses more difficult. According to more preferred embodiments, the anionic surface active agent is employed at about 0.5 to about 15 weight percent, more preferably at about 1 to about 10 weight percent.

The cleaning composition may optionally include other types of surface active agents in addition to the anionic surface active agent. The additional surface active agent may include materials having relatively good cleaning ability for contact lens deposits, in order to supplement the cleaning ability of the anionic surface active agent, as well as materials having relatively minor cleaning ability for the deposits.

Preferred additional surface active agents are nonionic surface active agents. Representative nonionic surface active agents include poloxa er surface active agents, such as the surface active agents available under the trade name Pluronic from BASF Wyandotte Corp., Parsippany, New Jersey, USA. The poloxamer surface active agents are polyoxyethylene, polyoxypropylene block copolymers that conform generally to the formula: CH₃

I

HO (CH₂CH₂0) _x (CHCH₂0) _y (CH₂CH₂0) _XH (VIII )

wherein x and y designate the average units of polyoxyethylene and polyoxypropylene, respectively.

Other representative nonionic surface active agents include ethoxylated alkyl phenols, such as various surface active agents available under the trade names Triton (Union Carbide, Tarrytown, New York, USA) and Igepal (Rhone-Poulenc) . The ethoxylated alkyl phenols generally conform to the formula:

R⁸-C₆H₄-(OCH₂CH₂)_rOH (IX)

wherein: R⁸ is C₆-C₂o alkyl, preferably C₈-C₉ alkyl; and r has a value within the range of 3 to 12, preferably from 9 to 10.

Other suitable nonionic surface active agents include ethanolamides and diethanolamides of the formulae: 0

_Q II

R⁹-C-NHCH₂CH₂0H (X)

0 II

R¹⁰-C-N(CH₂CH₂OH)2 (XI) wherein each of R⁹ and R¹⁰ is Cg-C₂o alkyl or alkenyl, preferably cocoamide DEA (a mixture of diethanolamides of coconut acid) and cocoamide MEA (a mixture of diethanolamides of coconut acid) . Commercial products include those available under the tradename Carsamide (Lonza Chemical Co. , Fairlawn, New Jersey, USA) or Witcamide (Witco Chemical Corp., New York, NY, USA).

Preferred are nonionic surface active agents which contain polyoxyethylene moieties, such as the polyoxyethylene, polyoxypropylene block copolymers and the ethoxylated alkyl phenols, as these agents appear to provide some degree of lubricity or wettability when used to clean contact lenses.

The composition may include one or more nonionic surface active agents at amounts from 0 to about 30 weight percent, more preferably at about 0.1 to about 25 weight percent, with about 2 to about 10 weight percent being especially preferred.

The compositions may optionally include a cationic surface active agent, present at 0 to about 5 weight percent. Representative cationic surface active agents include triquaternary phosphate esters, such as various cationic surface active agents available from Mona Industries, Inc., Patterson, New Jersey, USA under the tradename Monaquat. When present, the cationic surface active agent is preferably employed at about 0.001 to about 5 weight percent. Further, the compositions may optionally include about 0 to about 20 weight percent of an amphoteric surface active agent. Various amphoterics are available under the tradename Miranol (Rhone-Poulenc) . As an example, the product available under the tradename Miranol 2MHT includes a mixture of an anionic surface active agent (sodium trideceth sulfate) and an amphoteric (lauroamphocarboxy- glycinate) . When present, the amphoteric surface active agent is preferably employed at about 0.01 to about 20 weight percent.

Optionally, an abrasive agent may be employed in the cleaning compositions. The abrasive agent is a material containing water-insoluble particles, including inorganic particles or natural or synthetic polymeric particles. Preferably, the particles of the abrasive agent have an average particle size under about 20 microns (20 x 10~⁶ m) , and more preferably an average particles size of about 0.5 to about 5 microns. Inorganic abrasive particles include: alumina; silica, including amorphous silica or synthetic silica such as silica gel; aluminum silicate; titanium dioxide; and zirconium oxide. Particulate polymers include polymethylmethacrylate, nylons, cellulose acetate butyrate, polyvinylchloride and polycarbonate. The abrasive agent may be present at 0 to about 20 weight percent. When present in the compositions, the abrasive agent is preferably employed at about 0.1 to about 20 weight percent, more preferably at about 0.1 to about 10 weight percent, with 0.5 to about 5 weight percent being especially preferred.

If an abrasive agent is included in the composition, the compositions may further include a suspending agent, if desired, to provide a stable suspension of the abrasive in the composition. (Otherwise, the compositions may be shaken prior to use to suspend the abrasive agent.) Representative abrasive agents and suspending agents are described in detail in U.S. Patent Nos. 4,394,179 (Ellis) and 5,089,053 (Chou et al.), the disclosures of which are incorporated herein by reference.

Preferred suspending agents include polymeric viscosifying agents effective for increasing the viscosity of an alcohol-containing aqueous solution, such as crosslinked polymers of acrylic acid or natural gums. The suspending agent may be present at 0 to about 20 weight percent. When present, the suspending agent is preferably employed at about 0.1 to about 20 weight percent.

The cleaning compositions include as necessary buffering agents for buffering or adjusting pH of the composition, and/or tonicity adjusting agents for adjusting the tonicity of the composition. Representative buffering agents include: alkali metal salts such as potassium or sodium carbonates, acetates, borates, phosphates, citrates and hydroxides; and weak acids such as acetic, boric and phosphoric acids. Representative tonicity adjusting agents include: sodium and potassium chloride, and those materials listed as buffering agents. The tonicity agents may be employed in an amount effective to adjust the osmotic value of the final composition to a desired value. Generally, the buffering agents and/or tonicity adjusting agents may be included up to about 10 weight percent.

Additionally, the compositions may include wetting agents. Representative wetting agents include: cellulose derivatives, such as cationic cellulosic polymers, hydroxypropyl methylcellulose, hydroxyethylcellulose and methylcellulose; polyethyleneoxy-containing polymers (in addition to the above-described nonionic surfactants containing polyoxyethylene moieties) , such as polymers of polyethylene glycol; polyvinyl alcohol; and polyvinyl pyrrolidone. Such additives may be used in a wide range of concentrations as is known in the art.

The aliphatic monohydric alcohol component provides some preservative efficacy for maintaining sterility of the composition. Generally, when the alcohol is included in an amount of about 7.5 weight percent or higher, the cleaning composition is self- preserving. However, an optional preservative may be included in the composition in an antimicrobially effective amount, i.e., an amount which is effective to at least inhibit growth of microorganisms in the composition. Various antimicrobial agents are known in the art as useful in contact lens solutions, including: chlorhexidine (1,1'-hexamethylene-bis[5-(p- chlorophenyl) biguanide]) or water soluble salts thereof, such as chlorhexidine gluconate; polyhexamethylene biguanide (a polymer of hexamethylene biguanide, also referred to as polyaminopropyl biguanide) or water-soluble salts thereof, such as the polyhexamethylene biguanide hydrochloride available under the trade name Cosmocil CQ (ICI Americas Inc.); benzalkoniu chloride; and polymeric quaternary ammonium salts. Such optional antimicrobial agents may be included at 0 to about 5 weight percent, depending on the specific agent.

The compositions may further include a sequestering agent (or chelating agent) which can be present up to about 2.0 weight percent. Examples of preferred sequestering agents include ethylenediaminetetraacetic acid (EDTA) and its salts, with the disodium salt (disodium edetate) being especially preferred.

Additionally, the cleaning composition may optionally include a fragrance. Particularly, in compositions including isopropanol, an odor masking agent may be added to mask the odor of isopropanol if desired.

A contact lens is cleaned by exposing the lens to the cleaning composition, preferably by immersing the lens in the composition, followed by agitation, such as by rubbing the cleaning solution on the lens surface. The lens is then rinsed to remove the composition along with contaminants. The compositions are useful in removing deposits including deposits more difficult to clean from a lens, and various compositions provide wettability to the cleaned lens. The compositions are useful to the lens lab practitioner for removing deposits formed during processing and handling of the lens. Additionally, the compositions are useful in a regular cleaning regimen by a contact lens wearer to remove surface deposits formed from the tear film as well as deposits from external sources such as cosmetics. The compositions provide the desired cleaning efficacy without excessive scratching and without changing the power of the lens.

As previously mentioned, the compositions exclude nonpolar solvents such as cyclohexane, ethyl acetate and chloroform required in the cleaning compositions of U.S. Patent No. 4,421,665. It is believed that these solvents, if not adequately rinsed from the lens, can be harmful to the lens wearer. For example, cyclohexane and ethyl acetate may be toxic when contacted with, or absorbed by, the skin. Additionally, chloroform is considered a carcinogen and its use for various applications has been prohibited by the U.S. Food and Drug Administration. Especially preferred are contact lens cleaning compositions comprising:

(a) about 0.1 to about 30 weight percent of an anionic surface active agent, preferably about 0.5 to about 15 weight percent, with about 1 to about 10 weight percent being especially preferred;

(b) about 5 to about 40 weight percent of at least one member selected from the group consisting of ethanol and isopropanol, preferably about 7.5 to about 20 weight percent, with 7.5 to about 15 weight percent being especially preferred;

(c) 0 to about 30 weight of a nonionic surface active agent, preferably about 0.1 to about 25 weight percent, with about 2 to about 20 weight percent being especially preferred;

(d) 0 to about 20 weight percent of an abrasive agent;

(e) 0 to about 10 weight percent weight of at least one member selected from the group consisting of buffering agents and tonicity adjusting agents; and

(f) 0 to about 5 weight percent of a cationic surface active agent.

The following examples further illustrate preferred embodiments of the invention. EΣAMPLES 1-3

Contact lens cleaning compositions were prepared by mixing the components listed in Table 1. The principal active components of the commercial products are listed parenthetically, as well as concentration of the actives where available.

Pluronic F-127 was added with mixing to a measured amount of cold distilled water. After dissolution, the remaining surfactants, glycerine and about half the amount of isopropanol were added stepwise with mixing until dissolution was obtained. The remaining isopropanol was added, and the compositions were mixed in a closed flask to avoid evaporation of isopropanol. Compositions 1 and 2 were clear, whereas Composition 3 appeared pearlescent.

TABLE 1

Co ponent fWt. %) Cmpn 1 Cmpn 2 Cmpn 3

Isopropanol 12.00 10.00 7.50

Triton X-100

(Ethoxylated alkyl phenol) 2.50 1.00 1.00

Pluronic F-127 5.00 5.00 5.00

(Polyoxyethylene, polyoxypropylene block copolymer)

Miranol 2MHT 10.00

(Mixture including sodium trideceth sulfate

+ lauroamphocarboxyglycinate

+ hexylene glycol, 50%)

Varsulf SBFA-30 5.00

(^c12~^c14 fatty alcohol ethoxylated sulfosuccinate, 30%)

Standapol SCH-101 — 5.00

(Mixture including sodium lauryl sulfate

+ disodium oleamido sulfosuccinate,

30%)

Steol-7N — — 7.50

(Sodium laureth sulfate, 30%)

Carεamide CMEA — — 2.50

(Ethanolamide of coconut acid)

Glycerin 5.00 2.50 1.00

Distilled Water (qs to) 100 100 100 pH 7.8 5.7 8.1 EΣAMPLES 4-11 Contact lens cleaning compositions were prepared by mixing the components listed in Tables 2 and 3. The compositions including Pluronic F-127 (Examples 4, 5 and 8-11) were prepared following the general procedure of Example 1. Compositions 6 and 7 were prepared by adding about half the amount of isopropanol and the remaining components stepwise to a measured amount of water with mixing until dissolution was obtained. Subsequently, the remaining isopropanol was added as in Example 1.

TABLE 2

Component ( t. %) Cmpn 4 Cmpn 5 Cmpn 6 Cmpn 7

Isopropanol 20.00 10.00 10.00 10.00

Triton X-100 5.00 5.00 5.00 5.00

Pluronic F-127 15.00 15.00 — —

Tauranol WS 5.00 5.00 5.00 5.00 (Sodium methyl cocoyl taurate, 40%;)

Polyox WSR-301 0.20 0.20 0.20 0.20 (Polymer of ethylene oxide)

Cetearyl alcohol —— 1.00

Cremophor RH40 15.00 15.00 (Polyethyleneoxide hydrogenated castor oil)

Glycerin 0.20 0.20 0.20 0.20

Distilled Water 100 100 100 100

(qs to) pH 7.4 7.8 7.7 8.1 TABLE 3

Component (Wt. %) Cmpn 8 Cmpn 9 Cmpn 10 Cmpn 11

Isopropanol 20.00 20.00 20.00 20.00

Triton X-100 5.00 5.00 5.00 2.50

Pluronic F-127 15.00 10.00 15.00 15.00

Tauranol WS 5.00 5.00 — 7.50

Surfine WNT-A ------- —— 5.00 —-

(sodium pareth- -25- -7-carboxylate)

Polyox WSR-301 0.20 0.20 0.20 0.50

Docusate Sodium — 1.00 (Dioctyl sodium sulfosuccinate)

Distilled Water 100 100 100 100 (qs to) pH 7.9 8.1 8.9 7.8

EXAMPLES 12 AND 13

Contact lens cleaning compositions were prepared by adding about half the amount of isopropanol and the remaining components stepwise to a measured amount of water with mixing until dissolution was obtained. Subsequently, the remaining isopropanol was added as in Example 1. TABLE 4

Component (Wt. % ) Cmpn 12 Cmpn 13

Isopropanol 10.00 10.00

Triton X-100 5.00 4.36

Steol-7N 7.50

Sipex EST-30 — 32.70

(Sodium trideceth sulfate, 30%)

Bio Soft LD-190 1.50

(90% mixture including sodium dodecylbenzene sulfonate)

Monoquat PTC — 1.635

(Triquaternary phosphate ester cationic surfactant, 45%)

Sodium Phosphate 0.50 0.545

Sodium Chloride 5.00 —

Glycerin 2.50 —

Distilled Water (qs to) 100 100 pH 8.3 7.9

EXAMPLES 14 AND 15 The following contact lens cleaning compositions were prepared by mixing Pluronic F-127 with a measured amount of distilled water. After dissolution, about half the amount of isopropanol and the remaining components were added stepwise with mixing. The remaining isopropanol was added with mixing in a closed flask to avoid evaporation of isopropanol. Syloid-244 is the tradename for a gel containing synthetic amorphous silica having an average particle size of about 2.5 microns (available from W. R. Grace Co., Baltimore, Maryland, USA) .

TABLE 5

Component (Wt. %. Cmpn 14 Cmpn 15

Isopropanol 10.00 10.00

Triton X-100 5.00 5.00

Pluronic F-127 15.00 15.00

Tauranol WS 5.00 5.00

Polyox WSR-301 0.10 0.10

Syloid-244 — 2.00

Titanium Dioxide — 0.75

Glycerin 0.20 0.20

Distilled Water (qs to) 100 100 pH 7.9 7.8

EXAMPLE 16 Pluronic F-127 was added with mixing to a measured amount of cold distilled water. After dissolution of this surfactant was obtained, the remaining components were added stepwise with mixing until dissolution was obtained. Ethanol was added last with mixing in a closed flask to avoid evaporation. TABLE 6

Component (Wt. %) Cmpn 16

Ethanol 10.00

Triton X-100 5.00

Pluronic F-127 5.00

Tauranol WS 5.00

Polyox WSR-301 0.10

Glycerin 0.20

Distilled Water (qs to) 100

EXAMPLE 17 Pluronic F-127 was added with mixing to a measured amount of cold distilled water. After dissolution, the other components listed in Table 7 (except for Carbopol 940, isopropanol and triethanolamine) were added stepwise with mixing. Carbopol 940 was added and dispersed with mixing at room temperature for about 30 minutes. Isopropanol was added with mixing in a closed flask to avoid evaporation. Triethanolamine was added slowly to the final composition. Carbopol 940 is the tradename of a crosslinked polymer of acrylic acid, B. F. Goodrich Chemical Co., Cleveland, Ohio, USA. TABLE 7

Component (Wt. %) Cmpn 17

Isopropanol 10.00

Triton X-100 5.00

Pluronic F-127 5.00

Tauranol WS 5.00

Polyox WSR-301 0.10

Syloid-244 2.00

Carbopol 940 0.50

Glycerin 0.20

Triethanolamine 0.80

Distilled Water (qs to) 100

EXAMPLE 18

Six rigid gas permeable (RGP) lenses formed of a fluorosilicon acrylate polymer were subjected to a cleaning and conditioning regimen. Prior to the regimen, the basecurve, power and surface quality of each lens was measured. Initially, each lens had a comparable basecurve, power, and surface quality.

Each lens was initially conditioned with a commercial RGP conditioning (soaking and wetting) solution. Subsequently, each lens was subjected to 30 treatment cycles, wherein each cycle included: (1) treatment with a cleaning composition; followed by (2) treatment with the commercial conditioning solution. For the cleaning segment of the regimen, Lenses 1 and 2 were treated with MiraFlow* Extra-Strength Daily Cleaner (CIBA Vision Corp.), containing as principal active ingredients isopropanol, poloxamer 407 (a polyoxyethylene, polyoxypropylene block copolymer such as available under the trade name Pluronic F-127) and an amphoteric imidazole surfactant. Lenses 3 and 4 were treated with Composition 14 of Table 5, and lenses 5 and 6 were treated with Composition 15 of Table 5. For the conditioning segment of the regimen, each lens was treated with the same conditioning solution. Following the 30-cycle treatment regimen, the basecurve, power and surface quality of each lens were measured. The results are reported in Table 8, where scratching of the cleaned lenses is ranked relative to the other lens groups.

TABLE 8

Basecurve Power Surface Oualitv

Lens Initial Final Initial Final Initial Final

1 7.89 8.03 -2.75 -2.75 0 +++

2 7.96 8.01 -2.75 -2.75 0 +++

3 8.02 8.03 -2.75 -2.75 0 ++

4 7.98 8.00 -2.75 -2.75 0 ++

5 7.98 8.01 -2.75 -2.75 0 +

6 7.96 8.01 -2.75 -2.75 0 ^' +

0 Polished lens surface

+ Minor scratches

++ Moderate scratches

+++ Heavy scratches

The lenses cleaned with cleaning compositions of the present invention exhibited less surface scratching than lenses cleaned with the MiraFlow* Extra-Strength brand alcohol-containing cleaner.

Although certain preferred embodiments have been described, it is understood that the invention is not limited thereto and modifications and variations would be evident to a person of ordinary skill in the art.

We claim:

Claims

1. An aqueous contact lens cleaning composition comprising:

(a) an anionic surface active agent; and

(b) an aliphatic monohydric alcohol, wherein said composition excludes cyclohexane, ethyl acetate and chloroform.

2. The composition of claim 1, wherein the alcohol is at least one member selected from the group consisting of ethanol and isopropanol.

3. The composition of claim 1, wherein the anionic surface active agent includes at least one member selected from the group consisting of sulfated and sulfonated anionic surface active agents.

4. The composition of claim 3, wherein the anionic surface active agent includes at least one member selected from the group consisting of sodium methyl cocoyl taurate, sodium trideceth sulfate and sodium laureth sulfate.

5. The composition of claim 1, further comprising a nonionic surface active agent.

6. The composition of claim 5, wherein the nonionic surface active agent includes at least one member selected from the group consisting of polyoxyethylene, polyoxypropylene block copolymers and ethoxylated alkyl phenols.

7. The composition of claim 1, further comprising an abrasive agent.

8. The composition of claim 1, further comprising a preservative agent.

9. The composition of claim 1, further comprising a cationic surface active agent.

10. The composition of claim 1, further comprising a fragrance.

11. The composition of claim 1, comprising:

(a) about 0.1 to about 30 weight percent of an anionic surface active agent;

(b) about 5 to about 40 weight percent of at least one member selected from the group consisting of ethanol and isopropanol;

(c) 0 to about 30 weight of a nonionic surface active agent;

(d) 0 to about 20 weight percent of an abrasive agent;

<e) 0 to about 10 weight percent weight of at least one member selected from the group consisting of buffering agents and tonicity adjusting agents; and

(f) 0 to about 5 weight percent of a cationic surface active agent.

12. The composition of claim 1, comprising:

(a) about 1 to about 10 percent of an anionic surface active agent;

(b) about 7.5 to about 20 weight percent of at least one member selected from the group consisting of ethanol and isopropanol; (c) about 2 to about 20 weight percent of a nonionic surface active agent;

(d) 0 to about 20 weight percent of an abrasive agent;

(f) 0 to about 5 weight percent of a cationic surface active agent.

13. The composition of claim 12, including about 0.1 to about 10 weight percent of the abrasive agent.

14. A method of cleaning a contact lens comprising exposing said contact lens to an aqueous composition comprising an anionic surface active agent and an aliphatic monohydric alcohol, said composition excluding cyclohexane, ethyl acetate and chloroform.

15. The method of claim 14, wherein the alcohol is at least one member selected from the group consisting of ethanol and isopropanol.

16. The method of claim 14, wherein the anionic surface active agent includes at least one member selected from the group consisting of sodium methyl cocoyl taurate, sodium trideceth sulfate and sodium laureth sulfate.

17. The method of claim 14, wherein the composition further comprises a nonionic surface active agent.

18. The method of claim 17, wherein the nonionic surface active agent includes at least one member selected from the group consisting of polyoxyethylene, polyoxypropylene block copolymers and ethoxylated alkyl phenols.

19. The method of claim 14, wherein the composition further comprises an abrasive agent.

20. The method of claim 14, wherein the composition comprises:

(a) about 0.1 to about 30 weight percent of the anionic surface active agent;

(c) 0 to about 30 weight of a nonionic surface active agent;

(d) 0 to about 20 weight percent of an abrasive agent;

(f) 0 to about 5 weight percent of a cationic surface active agent.

21. The method of claim 14, wherein the composition comprises:

(a) about 1 to about 10 percent of an anionic surface active agent; (b) about 7.5 to about 20 weight percent of at least one member selected from the group consisting of ethanol and isopropanol;

(c) about 2 to about 20 weight percent of a nonionic surface active agent;

(d) 0 to about 20 weight percent of an abrasive agent;

(f) 0 to about 5 weight percent of a cationic surface active agent.

22. The method of claim 14, wherein the contact lens is formed of a rigid gas permeable silicon acrylate or fluorosilicon acrylate polymer.

23. A method of cleaning a contact lens having contaminants thereon comprising:

(a) exposing said contact lens to an aqueous composition comprising an anionic surface active agent and an aliphatic monohydric alcohol, said composition excluding nonpolar solvents;

(b) rubbing said composition against said contact lens; and

(c) rinsing said lens to remove said composition and contaminants therewith.