U.S. patent application number 12/248198 was filed with the patent office on 2009-07-09 for packaging solutions.
Invention is credited to Yu-Chin Lai, Weihong Lang.
Application Number | 20090173643 12/248198 |
Document ID | / |
Family ID | 40456414 |
Filed Date | 2009-07-09 |
United States Patent
Application |
20090173643 |
Kind Code |
A1 |
Lai; Yu-Chin ; et
al. |
July 9, 2009 |
Packaging Solutions
Abstract
Packaging systems for storing ophthalmic devices such as contact
lenses and to methods for packaging such ophthalmic devices with
solutions to improve the comfort of the lenses during wear are
disclosed. A packaging system includes an ophthalmic device stored
in an aqueous packaging solution comprising a copolymer which is
the reaction product of one or more polymerizable polyhydric
alcohols and one or more polymerizable fluorine-containing
monomers.
Inventors: |
Lai; Yu-Chin; (Pittsford,
NY) ; Lang; Weihong; (Amston, CT) |
Correspondence
Address: |
Bausch & Lomb Incorporated
One Bausch & Lomb Place
Rochester
NY
14604-2701
US
|
Family ID: |
40456414 |
Appl. No.: |
12/248198 |
Filed: |
October 9, 2008 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
61019863 |
Jan 9, 2008 |
|
|
|
Current U.S.
Class: |
206/5.1 ;
53/426 |
Current CPC
Class: |
A45C 11/005 20130101;
C08F 220/28 20130101; A61L 12/04 20130101; C08F 220/24 20130101;
B65B 25/008 20130101 |
Class at
Publication: |
206/5.1 ;
53/426 |
International
Class: |
A45C 11/04 20060101
A45C011/04; B65B 55/02 20060101 B65B055/02 |
Claims
1. A method of preparing a package comprising a storable, sterile
ophthalmic device, the method comprising: (a) immersing an
ophthalmic device in an aqueous packaging solution comprising a
copolymer which is the reaction product of one or more
polymerizable polyhydric alcohols and one or more polymerizable
fluorine-containing monomers, wherein the solution has an
osmolality of at least about 200 mOsm/kg and a pH in the range of
about 6 to about 9; (b) packaging the solution and the device in a
manner preventing contamination of the device by microorganisms;
and (c) sterilizing the packaged solution and device.
2. The method of claim 1, wherein the ophthalmic device is a
contact lens.
3. The method of claim 1, wherein the ophthalmic device is a
silicone hydrogel contact lens.
4. The method of claim 1, wherein the polymerizable polyhydric
alcohol is a polyhydric alcohol terminated with a polymerizable
ethylenically unsaturated-containing radical and the polymerizable
fluorine-containing monomer is a fluorine-containing monomer
terminated with a polymerizable ethylenically
unsaturated-containing radical.
5. The method of claim 1, wherein the polymerizable polyhydric
alcohol is selected from the group consisting of a polymerizable
glycerol-containing compound, polymerizable erythritol-containing
compound, polymerizable xylitol-containing compound, polymerizable
sorbitol-containing compound and mixtures thereof.
6. The method of claim 1, wherein the polymerizable polyhydric
alcohol is selected from the group consisting of
glycerol(meth)acrylate, erythritol(meth)acrylate, xylitol
(meth)acrylate, sorbitol(meth)acrylate and mixtures thereof.
7. The method of claim 1, wherein the polymerizable
fluorine-containing monomer is a fluorinated(meth)acrylate
monomer.
8. The method of claim 6, wherein the polymerizable
fluorine-containing monomer is selected from the group consisting
of 2,2,2-trifluoroethyl(meth)acrylate, 2,2,3,3-tetrafluoropropyl
(meth)acrylate, 2,2,3,3,3,-pentafluoropropyl(meth)acrylate,
1-trifluoromethyl-2,2,2-trifluoroethyl(meth)acrylate, 1H,
1H,5H-octafluoropentyl (meth)acrylate,
hexafluoroisopropyl(meth)acrylate, 2,2,3,3,4,4-hexafluorobutyl
(meth)acrylate and mixtures thereof.
9. The method of claim 1, wherein the copolymer is terminated with
an ethylenically unsaturated-containing radical.
10. The method of claim 1, wherein the solution does not contain an
effective disinfecting amount of a disinfecting agent.
11. The method of claim 1, wherein the solution does not contain a
germicide compound.
12. A packaging system for the storage of an ophthalmic device
comprising a sealed container containing one or more unused
ophthalmic device immersed in an aqueous packaging solution
comprising a copolymer which is the reaction product of one or more
polymerizable polyhydric alcohols and one or more polymerizable
fluorine-containing monomers, wherein the solution has an
osmolality of at least about 200 mOsm/kg, a pH of about 6 to about
9 and is heat sterilized.
13. The packaging system of claim 12, wherein the ophthalmic device
is a contact lens.
14. The packaging system of claim 12, wherein the polymerizable
polyhydric alcohol is a polyhydric alcohol terminated with a
polymerizable ethylenically unsaturated-containing radical and the
polymerizable fluorine-containing monomer is a fluorine-containing
monomer terminated with a polymerizable ethylenically
unsaturated-containing radical.
15. The packaging system of claim 12, wherein the polymerizable
polyhydric alcohol is selected from the group consisting of a
polymerizable glycerol-containing compound, polymerizable
erythritol-containing compound, polymerizable xylitol-containing
compound, polymerizable sorbitol-containing compound and mixtures
thereof.
16. The packaging system of claim 12, wherein the polymerizable
polyhydric alcohol is selected from the group consisting of
glycerol(meth)acrylate, erythritol(meth)acrylate,
xylitol(meth)acrylate, sorbitol(meth)acrylate and mixtures
thereof.
17. The packaging system of claim 12, wherein the polymerizable
fluorine-containing monomer is a fluorinated(meth)acrylate
monomer.
18. The packaging system of claim 16, wherein the polymerizable
fluorine-containing monomer is selected from the group consisting
of 2,2,2-trifluoroethyl(meth)acrylate,
2,2,3,3-tetrafluoropropyl(meth)acrylate,
2,2,3,3,3,-pentafluoropropyl(meth)acrylate,
1-trifluoromethyl-2,2,2-trifluoroethyl(meth)acrylate, 1H,
1H,5H-octafluoropentyl(meth)acrylate,
hexafluoroisopropyl(meth)acrylate, 2,2,3,3,4,4-hexafluorobutyl
(meth)acrylate and mixtures thereof.
19. The packaging system of claim 12, wherein the copolymer is
terminated with an ethylenically unsaturated-containing
radical.
20. The packaging system of claim 12, wherein the solution does not
contain an effective disinfecting amount of a disinfecting
agent.
21. The packaging system of claim 12, wherein the solution does not
contain a germicide compound.
22. The packaging system of claim 12, wherein the package is heat
sterilized subsequent to sealing of the package.
23. A packaging system for the storage of an ophthalmic device
comprising: (a) an aqueous packaging solution comprising a
copolymer which is the reaction product of one or more
polymerizable polyhydric alcohols and one or more polymerizable
fluorine-containing monomers, wherein the solution has an
osmolality of at least about 200 mOsm/kg and a pH in the range of
about 6 to about 9; (b) at least one ophthalmic device; and (c) a
container for holding the solution and ophthalmic device sufficient
to preserve the sterility of the solution and ophthalmic device,
wherein the solution does not contain an effective disinfecting
amount of a disinfecting agent.
24. The packaging system of claim 23, wherein the polymerizable
polyhydric alcohol is selected from the group consisting of
glycerol(meth)acrylate, erythritol (meth)acrylate,
xylitol(meth)acrylate, sorbitol(meth)acrylate and mixtures thereof
and the polymerizable fluorine-containing monomer is selected from
the group consisting of 2,2,2-trifluoroethyl(meth)acrylate,
2,2,3,3-tetrafluoropropyl(meth)acrylate,
2,2,3,3,3,-pentafluoropropyl(meth)acrylate,
1-trifluoromethyl-2,2,2-trifluoroethyl(meth)acrylate, 1H,
1H,5H-octafluoropentyl(meth)acrylate,
hexafluoroisopropyl(meth)acrylate,
2,2,3,3,4,4-hexafluorobutyl(meth)acrylate and mixtures thereof.
25. The packaging system of claim 23, wherein the ophthalmic device
is a contact lens.
Description
[0001] This application claims the benefit of provisional patent
application No. 61/019,863 filed on Jan. 9, 2008 which is
incorporated by reference herein.
BACKGROUND OF THE INVENTION
[0002] 1. Technical Field
[0003] The present invention generally relates to packaging
solutions for ophthalmic devices such as contact lenses.
[0004] 2. Description of Related Art
[0005] Blister-packs and glass vials are typically used to
individually package each soft contact lens for sale to a customer.
Saline or deionized water is commonly used to store the lens in the
blister-packs, as mentioned in various patents related to the
packaging or manufacturing of contact lenses. Because lens material
may tend to stick to itself and to the lens package, packaging
solutions for blister-packs have sometimes been formulated to
reduce or eliminate lens folding and sticking. For this reason,
polyvinyl alcohol (PVA) has been used in contact-lens packaging
solutions.
[0006] It has been stated that if a lens is thoroughly cleaned
before insertion, lacrimal fluid can adequately wet the lens.
Furthermore, the difficulties of adding a surfactant to a packaging
solution, including the possibility of lowering shelf-life and/or
adverse reactions during heat sterilization, have further limited
the use of surfactants in a packaging solution for the purpose of
providing any possible or marginal effect on lens comfort. It is
only after a lens has been worn, when proteins or other deposits
have formed on the surface of the lens, that surfactants have been
used in standard lens-care solutions.
[0007] It is highly desirable that contact lens be as comfortable
as possible for wearers. Manufacturers of contact lenses are
continually working to improve the comfort of the lenses.
Nevertheless, many people who wear contact lenses still experience
dryness or eye irritation throughout the day and particularly
towards the end of the day. An insufficiently wetted lens at any
point in time will cause significant discomfort to the lens wearer.
Although wetting drops can be used as needed to alleviate such
discomfort, it would certainly be desirable if such discomfort did
not arise in the first place.
[0008] Poloxamine and poloxamers are examples of non-ionic
surfactants having one or more poly(oxyalkylene) chains.
Poloxamines and poloxamers are well-known wetting and lubricating
agents for contact lenses and have been used in lens wetting drops
and in lens-care solutions for treating lenses after use or while
in use in the eye. For example, U.S. Pat. No. 4,786,436 disclose
poloxamine as a wetting agent. Contact-lens rewetting drops
containing surfactants such as poloxamine and poloxamer have been
used to make contact lens wear more comfortable, to soothe the
eyes, and to moisten lenses to minimize dryness. Surfactants such
as poloxamine, poloxamer, and tyloxapol have been used in
multi-purpose solutions, for cleaning, wetting, and storing
lenses.
[0009] Certain combinations of poly(oxyalkylene) surfactants have
also been disclosed for use in the eye to preventively clean lenses
and inhibit deposits. For example, U.S. Pat. No. 5,209,865
discloses the combination of certain poloxamers and poloxamines to
maintain clean lenses in the eye.
[0010] U.S. Pat. No. 6,440,366 ("the '366 patent") discloses a
package containing a contact lens suitable for immediate use which
comprises (a) a solution comprising a non-ionic surfactant that is
a compound comprising at least 90 weight percent of
poly(oxyethylene) and poly(oxypropylene) segments, in one or more
block copolymer chains, and (b) an effective amount of a tonicity
adjusting agent such that the solution has an osmolality of 200 to
400 mOsm/kg; wherein the solution has a pH of about 6 to 8 and is
heat sterilized and lacks an effective disinfecting amount of a
disinfecting agent. The '366 patent further discloses that the
surfactant is a poly(oxypropylene)-poly(oxyethylene) adduct of
ethylene diamine.
[0011] It would be desirable to provide an improved packaging
system for ophthalmic devices such as a contact lens such that the
lens would be comfortable to wear in actual use and allow for
extended wear of the lens without irritation or other adverse
effects to the cornea.
SUMMARY OF THE INVENTION
[0012] In accordance with one embodiment of the present invention,
a method of preparing a package comprising a storable, sterile
ophthalmic device is provided comprising:
[0013] (a) immersing an ophthalmic device in an aqueous packaging
solution comprising a copolymer which is the reaction product of
one or more polymerizable polyhydric alcohols and one or more
polymerizable fluorine-containing monomers, wherein the solution
has an osmolality of at least about 200 mOsm/kg and a pH in the
range of about 6 to about 9;
[0014] (b) packaging the solution and the ophthalmic device in a
manner preventing contamination of the device by microorganisms;
and
[0015] (c) sterilizing the packaged solution and ophthalmic
device.
[0016] In accordance with a second embodiment of the present
invention, a packaging system for the storage of an ophthalmic
device is provided comprising a sealed container containing one or
more unused ophthalmic devices immersed in an aqueous packaging
solution comprising a copolymer which is the reaction product of
one or more polymerizable polyhydric alcohols and one or more
polymerizable fluorine-containing monomers, wherein the solution
has an osmolality of at least about 200 mOsm/kg, a pH of about 6 to
about 9 and is heat sterilized.
[0017] In accordance with a third embodiment of the present
invention, a packaging system for the storage of an ophthalmic
device is provided comprising:
[0018] (a) an aqueous packaging solution comprising a copolymer
which is the reaction product of one or more polymerizable
polyhydric alcohols and one or more polymerizable
fluorine-containing monomers, wherein the solution has an
osmolality of at least about 200 mOsm/kg and a pH in the range of
about 6 to about 9;
[0019] (b) at least one ophthalmic device; and
[0020] (c) a container for holding the solution and ophthalmic
device sufficient to preserve the sterility of the solution and
ophthalmic device, wherein the solution does not contain an
effective disinfecting amount of a disinfecting agent.
[0021] The aqueous packaging solutions of the present invention
containing at least a copolymer which is the reaction product of
one or more polymerizable polyhydric alcohols and one or more
polymerizable fluorine-containing monomers is believed to provide a
more uniform coating on the surface of an ophthalmic device such as
a contact lens thereby resulting in improved lubricity of the lens.
Thus, the lens will be more comfortable to wear in actual use and
would allow for the extended wear of the lens without irritation or
other adverse effects to the cornea.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0022] The present invention provides a packaging system for the
storage of ophthalmic devices intended for direct contact with body
tissue or body fluid. As used herein, the term "ophthalmic device"
refers to devices that reside in or on the eye. These lenses can
provide optical correction, wound care, drug delivery, diagnostic
functionality or cosmetic enhancement or effect or a combination of
these properties. Representative examples of such devices include,
but are not limited to, soft contact lenses, e.g., a soft, hydrogel
lens; soft, non-hydrogel lens and the like, hard contact lenses,
e.g., a hard, gas permeable lens material and the like, intraocular
lenses, overlay lenses, ocular inserts, optical inserts and the
like. As is understood by one skilled in the art, a lens is
considered to be "soft" if it can be folded back upon itself
without breaking. Any material known to produce an ophthalmic
device including a contact lens can be used herein.
[0023] The ophthalmic devices can be any material known in the art
capable of forming an ophthalmic device as described above. In one
embodiment, an ophthalmic device includes devices which are formed
from material not hydrophilic per se. Such devices are formed from
materials known in the art and include, by way of example,
polysiloxanes, perfluoropolyethers, fluorinated poly(meth)acrylates
or equivalent fluorinated polymers derived, e.g., from other
polymerizable carboxylic acids, polyalkyl(meth)acrylates or
equivalent alkylester polymers derived from other polymerizable
carboxylic acids, or fluorinated polyolefins, such as fluorinated
ethylene propylene polymers, or tetrafluoroethylene, preferably in
combination with a dioxol, e.g., perfluoro-2,2-dimethyl-1,3-dioxol.
Representative examples of suitable bulk materials include, but are
not limited to, Lotrafilcon A, Neofocon, Pasifocon, Telefocon,
Silafocon, Fluorsilfocon, Paflufocon, Silafocon, Elastofilcon,
Fluorofocon or Teflon AF materials, such as Teflon AF 1600 or
Teflon AF 2400 which are copolymers of about 63 to about 73 mol %
of perfluoro-2,2-dimethyl-1,3-dioxol and about 37 to about 27 mol %
of tetrafluoroethylene, or of about 80 to about 90 mol % of
perfluoro-2,2-dimethyl-1,3-dioxol and about 20 to about 10 mol % of
tetrafluoroethylene.
[0024] In another embodiment, an ophthalmic device includes devices
which are formed from material hydrophilic per se, since reactive
groups, e.g., carboxy, carbamoyl, sulfate, sulfonate, phosphate,
amine, ammonium or hydroxy groups, are inherently present in the
material and therefore also at the surface of an ophthalmic device
manufactured therefrom. Such devices are formed from materials
known in the art and include, by way of example, polyhydroxyethyl
acrylate, polyhydroxyethyl methacrylate (HEMA), polyvinyl
pyrrolidone (PVP), polyacrylic acid, polymethacrylic acid,
polyacrylamide, polydimethylacrylamide (DMA), polyvinyl alcohol and
the like and copolymers thereof, e.g., from two or more monomers
selected from hydroxyethyl acrylate, hydroxyethyl methacrylate,
N-vinyl pyrrolidone, acrylic acid, methacrylic acid, acrylamide,
dimethyl acrylamide, vinyl alcohol and the like. Representative
examples of suitable bulk materials include, but are not limited
to, Polymacon, Tefilcon, Methafilcon, Deltafilcon, Bufilcon,
Phemfilcon, Ocufilcon, Focofilcon, Etafilcon, Hefilcon, Vifilcon,
Tetrafilcon, Perfilcon, Droxifilcon, Dimefilcon, Isofilcon,
Mafilcon, Nelfilcon, Atlafilcon and the like. Examples of other
suitable bulk materials include balafilcon A, hilafilcon A,
alphafilcon A, bilafilcon B and the like.
[0025] In another embodiment, ophthalmic devices include devices
which are formed from material which are amphiphilic segmented
copolymers containing at least one hydrophobic segment and at least
one hydrophilic segment which are linked through a bond or a bridge
member.
[0026] It is particularly useful to employ biocompatible materials
herein including both soft and rigid materials commonly used for
ophthalmic lenses, including contact lenses. In general,
non-hydrogel materials are hydrophobic polymeric materials that do
not contain water in their equilibrium state. Typical non-hydrogel
materials comprise silicone acrylics, such as those formed bulky
silicone monomer (e.g., tris(trimethylsiloxy)silylpropyl
methacrylate, commonly known as "TRIS" monomer), methacrylate
end-capped poly(dimethylsiloxane) prepolymer, or silicones having
fluoroalkyl side groups (polysiloxanes are also commonly known as
silicone polymers).
[0027] Hydrogels in general are a well-known class of materials
that comprise hydrated, crosslinked polymeric systems containing
water in an equilibrium state. Accordingly, hydrogels are
copolymers prepared from hydrophilic monomers. In the case of
silicone hydrogels, the hydrogel copolymers are generally prepared
by polymerizing a mixture containing at least one device-forming
silicone-containing monomer and at least one device-forming
hydrophilic monomer. Either the silicone-containing monomer or the
hydrophilic monomer can function as a crosslinking agent (a
crosslinker being defined as a monomer having multiple
polymerizable functionalities) or a separate crosslinker may be
employed. Silicone hydrogels typically have a water content between
about 10 to about 80 weight percent.
[0028] Representative examples of useful hydrophilic monomers
include, but are not limited to, amides such as
N,N-dimethylacrylamide and N,N-dimethylmethacrylamide; cyclic
lactams such as N-vinyl-2-pyrrolidone; and (meth)acrylated
poly(alkene glycols), such as poly(diethylene glycols) of varying
chain length containing monomethacrylate or dimethacrylate end
caps. Still further examples are the hydrophilic vinyl carbonate or
vinyl carbamate monomers disclosed in U.S. Pat. No. 5,070,215, and
the hydrophilic oxazolone monomers disclosed in U.S. Pat. No.
4,910,277, the disclosures of which are incorporated herein by
reference. Other suitable hydrophilic monomers will be apparent to
one skilled in the art. For example, 2-hydroxyethylmethacrylate
(HEMA) is a well-known hydrophilic monomer that may be used in
admixture with the aforementioned hydrophilic monomers.
[0029] The monomer mixtures may also include a second
device-forming monomer including a copolymerizable group and a
reactive functional group. The copolyermizable group is preferably
an ethylenically unsaturated group, such that this device-forming
monomer copolymerizes with the hydrophilic device-forming monomer
and any other device-forming monomers in the initial device-forming
monomer mixture. Additionally, the second monomer can include a
reactive functional group that reacts with a complementary reactive
group of the copolymer which is the reaction product of one or more
polymerizable polyhydric alcohols and one or more polymerizable
fluorine-containing monomers. In other words, after the device is
formed by copolymerizing the device-forming monomer mixture, the
reactive functional groups provided by the second device-forming
monomers remain to react with a complementary reactive moiety of
the copolymer.
[0030] Preferred reactive groups of the second device-forming
monomers include epoxide groups. Accordingly, preferred second
device-forming monomers are those that include both an
ethylenically unsaturated group (that permits the monomer to
copolymerize with the hydrophilic device-forming monomer) and the
epoxide group (that does not react with the hydrophilic
device-forming monomer but remains to react with the copolymer is
the reaction product of one or more polymerizable polyhydric
alcohols and one or more polymerizable fluorine-containing
monomers). Examples include glycidyl methacrylate, glycidyl
acrylate, glycidyl vinylcarbonate, glycidyl vinylcarbamate,
4-vinyl-1-cyclohexene-1,2-epoxide and the like.
[0031] As mentioned, one preferred class of ophthalmic device
substrate materials are silicone hydrogels. In this case, the
initial device-forming monomer mixture further comprises a
silicone-containing monomer. Applicable silicone-containing
monomeric materials for use in the formation of silicone hydrogels
are well known in the art and numerous examples are provided in
U.S. Pat. Nos. 4,136,250; 4,153,641; 4,740,533; 5,034,461;
5,070,215; 5,260,000; 5,310,779; and 5,358,995. Specific examples
of suitable materials for use herein include those disclosed in
U.S. Pat. Nos. 5,310,779; 5,387,662; 5,449,729; 5,512,205;
5,610,252; 5,616,757; 5,708,094; 5,710,302; 5,714,557 and
5,908,906, the contents of which are incorporated by reference
herein.
[0032] Representative examples of applicable silicon-containing
monomers include bulky polysiloxanylalkyl(meth)acrylic monomers.
The term "monomer" and like terms as used herein denote relatively
low molecular weight compounds that are polymerizable by, for
example, free radical polymerization, as well as higher molecular
weight compounds also referred to as "prepolymers",
"macromonomers", and related terms. The term "(meth)" as used
herein denotes an optional methyl substituent. Accordingly, terms
such as "(meth)acrylate" denotes either methacrylate or acrylate,
and "(meth)acrylic acid" denotes either methacrylic acid or acrylic
acid.
[0033] An example of a bulky polysiloxanylalkyl(meth)acrylic
monomer is represented by the structure of Formula I:
##STR00001##
wherein X denotes --O-- or --NR--; each R.sup.1 independently
denotes hydrogen or methyl; each R.sup.2 independently denotes a
lower alkyl radical, phenyl radical or a group represented by
##STR00002##
wherein each R.sup.2' denotes a lower alkyl or phenyl radical; and
h is 1 to 10.
[0034] Examples of bulky monomers are methacryloxypropyl
tris(trimethyl-siloxy)silane or tris(trimethylsiloxy)silylpropyl
methacrylate, sometimes referred to as TRIS and
tris(trimethylsiloxy)silylpropyl vinyl carbamate, sometimes
referred to as TRIS-VC and the like.
[0035] Such bulky monomers may be copolymerized with a silicone
macromonomer, which is a poly(organosiloxane) capped with an
unsaturated group at two or more ends of the molecule. U.S. Pat.
No. 4,153,641 discloses, for example, various unsaturated groups
such as acryloxy or methacryloxy groups.
[0036] Another class of representative silicone-containing monomers
includes, but is not limited to, silicone-containing vinyl
carbonate or vinyl carbamate monomers such as, for example,
1,3-bis[4-vinyloxycarbonyloxy)but-1-yl]tetramethyl-disiloxane;
3-(trimethylsilyl)propyl vinyl carbonate;
3-(vinyloxycarbonylthio)propyl-[tris(trimethylsiloxy)silane];
3-[tris(trimethylsiloxy)silyl]propyl vinyl carbamate;
3-[tris(trimethylsiloxy)silyl]propyl allyl carbamate;
3-[tris(trimethylsiloxy)silyl]propyl vinyl carbonate;
t-butyldimethylsiloxyethyl vinyl carbonate; trimethylsilylethyl
vinyl carbonate; trimethylsilylmethyl vinyl carbonate and the like
and mixtures thereof.
[0037] Another class of silicon-containing monomers includes
polyurethane-polysiloxane macromonomers (also sometimes referred to
as prepolymers), which may have hard-soft-hard blocks like
traditional urethane elastomers. They may be end-capped with a
hydrophilic monomer such as 2-hydroxyethyl methacrylate (HEMA).
Examples of such silicone urethanes are disclosed in a variety or
publications, including Lai, Yu-Chin, "The Role of Bulky
Polysiloxanylalkyl Methacryates in Polyurethane-Polysiloxane
Hydrogels," Journal of Applied Polymer Science, Vol. 60, 1193-1199
(1996). PCT Published Application No. WO 96/31792 discloses
examples of such monomers, which disclosure is hereby incorporated
by reference in its entirety. Further examples of silicone urethane
monomers are represented by Formulae II and III:
E(*D*A*D*G).sub.a*D*A*D*E'; or (II)
E(*D*G*D*A).sub.a*D*A*D*E'; or (III)
wherein:
[0038] D independently denotes an alkyl diradical, an alkyl
cycloalkyl diradical, a cycloalkyl diradical, an aryl diradical or
an alkylaryl diradical having 6 to about 30 carbon atoms;
[0039] G independently denotes an alkyl diradical, a cycloalkyl
diradical, an alkyl cycloalkyl diradical, an aryl diradical or an
alkylaryl diradical having 1 to about 40 carbon atoms and which may
contain ether, thio or amine linkages in the main chain;
[0040] * denotes a urethane or ureido linkage;
[0041] a is at least 1;
[0042] A independently denotes a divalent polymeric radical of
Formula IV:
##STR00003##
wherein each R.sup.s independently denotes an alkyl or
fluoro-substituted alkyl group having 1 to about 10 carbon atoms
which may contain ether linkages between the carbon atoms; m' is at
least 1; and p is a number that provides a moiety weight of about
400 to about 10,000;
[0043] each of E and E' independently denotes a polymerizable
unsaturated organic radical represented by Formula V:
##STR00004##
wherein: R.sup.3 is hydrogen or methyl; [0044] R.sup.4 is hydrogen,
an alkyl radical having 1 to 6 carbon atoms, or a --CO--Y--R.sup.6
radical [0045] wherein Y is --O--, --S-- or --NH--; [0046] R.sup.5
is a divalent alkylene radical having 1 to about 10 carbon atoms;
[0047] R.sup.6 is a alkyl radical having 1 to about 12 carbon
atoms; [0048] X denotes --CO or --OCO--; [0049] Z denotes --O-- or
--NH--; [0050] Ar denotes an aromatic radical having about 6 to
about 30 carbon atoms; [0051] w is 0 to 6; x is 0 or 1; y is 0 or
1; and z is 0 or 1.
[0052] A preferred silicone-containing urethane monomer is
represented by Formula VI:
##STR00005##
wherein m is at least 1 and is preferably 3 or 4, a is at least 1
and preferably is 1, p is a number which provides a moiety weight
of about 400 to about 10,000 and is preferably at least about 30,
R.sup.7 is a diradical of a diisocyanate after removal of the
isocyanate group, such as the diradical of isophorone diisocyanate,
and each E'' is a group represented by:
##STR00006##
[0053] In another embodiment of the present invention, a silicone
hydrogel material comprises (in bulk, that is, in the monomer
mixture that is copolymerized) about 5 to about 50 percent, and
preferably about 10 to about 25, by weight of one or more silicone
macromonomers, about 5 to about 75 percent, and preferably about 30
to about 60 percent, by weight of one or more
polysiloxanylalkyl(meth)acrylic monomers, and about 10 to about 50
percent, and preferably about 20 to about 40 percent, by weight of
a hydrophilic monomer. In general, the silicone macromonomer is a
poly(organosiloxane) capped with an unsaturated group at two or
more ends of the molecule. In addition to the end groups in the
above structural formulas, U.S. Pat. No. 4,153,641 discloses
additional unsaturated groups, including acryloxy or methacryloxy.
Fumarate-containing materials such as those disclosed in U.S. Pat.
Nos. 5,310,779; 5,449,729 and 5,512,205 are also useful substrates
in accordance with the invention. Preferably, the silane
macromonomer is a silicon-containing vinyl carbonate or vinyl
carbamate or a polyurethane-polysiloxane having one or more
hard-soft-hard blocks and end-capped with a hydrophilic
monomer.
[0054] The above silicone materials are merely exemplary, and other
materials for use as substrates that can benefit by being packaged
in the packaging solution according to the present invention and
have been disclosed in various publications and are being
continuously developed for use in contact lenses and other medical
devices can also be used. For example, an ophthalmic lens for use
herein can be a cationic lens such as a cationic contact lens or
fluorinated silicone-containing monomers. Such monomers have been
used in the formation of fluorosilicone as disclosed in, for
example, U.S. Pat. Nos. 4,954,587; 5,010,141 and 5,079,319. The use
of silicone-containing monomers having certain fluorinated side
groups, i.e., --(CF.sub.2)--H, have been found to improve
compatibility between the hydrophilic and silicone-containing
monomeric units. See, e.g., U.S. Pat. Nos. 5,321,108 and
5,387,662.
[0055] Ophthalmic devices such as contact lenses for application of
the present invention can be manufactured employing various
conventional techniques, to yield a shaped article having the
desired posterior and anterior lens surfaces. In one embodiment, an
ophthalmic device can be prepared by polymerizing the monomeric
mixtures to form a product that can be subsequently formed into the
appropriate shape by, for example, lathing, injection molding,
compression molding, cutting and the like. For example, in
producing contact lenses, the initial monomeric mixture may be
polymerized in tubes to provide rod-shaped articles, which are then
cut into buttons. The buttons may then be lathed into contact
lenses.
[0056] Alternately, the ophthalmic devices may be cast directly in
molds, e.g., polypropylene molds, from the monomeric mixtures,
e.g., by spincasting and static casting methods. Spincasting
methods are disclosed in U.S. Pat. Nos. 3,408,429 and 3,660,545,
and static casting methods are disclosed in U.S. Pat. Nos.
4,113,224, 4,197,266, and 5,271,875. Spincasting methods involve
charging the monomer mixture to a mold, and spinning the mold in a
controlled manner while exposing the monomer mixture to a radiation
source such as UV light. Static casting methods involve charging
the monomeric mixture between two mold sections, one mold section
shaped to form the anterior lens surface and the other mold section
shaped to form the posterior lens surface, and curing the monomeric
mixture while retained in the mold assembly to form a lens, for
example, by free radical polymerization of the monomeric mixture.
Examples of free radical reaction techniques to cure the lens
material include thermal radiation, infrared radiation, electron
beam radiation, gamma radiation, ultraviolet (UV) radiation, and
the like; or combinations of such techniques may be used. U.S. Pat.
No. 5,271,875 describes a static cast molding method that permits
molding of a finished lens in a mold cavity defined by a posterior
mold and an anterior mold. As an additional method, U.S. Pat. No.
4,555,732 discloses a process where an excess of a monomeric
mixture is cured by spincasting in a mold to form a shaped article
having an anterior lens surface and a relatively large thickness,
and the posterior surface of the cured spincast article is
subsequently lathed to provide a contact lens having the desired
thickness and posterior lens surface.
[0057] Polymerization may be facilitated by exposing the mixture to
heat and/or radiation, such as ultraviolet light, visible light, or
high energy radiation. A polymerization initiator may be included
in the mixture to facilitate the polymerization step.
Representative examples of free radical thermal polymerization
initiators include organic peroxides such as acetal peroxide,
lauroyl peroxide, decanoyl peroxide, stearoyl peroxide, benzoyl
peroxide, tertiarylbutyl peroxypivalate, peroxydicarbonate, and the
like. Representative UV initiators are those known in the art and
include benzoin methyl ether, benzoin ethyl ether, Darocure 1173,
1164, 2273, 1116, 2959, 3331 (EM Industries) and Igracure 651 and
184 (Ciba-Geigy), and the like. Generally, the initiator will be
employed in the monomeric mixture at a concentration of about 0.01
to 1 percent by weight of the total mixture.
[0058] After producing a lens having the desired final shape, it is
desirable to remove residual solvent from the lens before
edge-finishing operations. This is because, typically, an organic
diluent is included in the initial monomeric mixture in order to
minimize phase separation of polymerized products produced by
polymerization of the monomeric mixture and to lower the glass
transition temperature of the reacting polymeric mixture, which
allows for a more efficient curing process and ultimately results
in a more uniformly polymerized product. Sufficient uniformity of
the initial monomeric mixture and the polymerized product are of
particular concern for silicone hydrogels, primarily due to the
inclusion of silicone-containing monomers which may tend to
separate from the hydrophilic comonomer. Suitable organic diluents
include, for example, monohydric alcohols such as C.sub.6-C.sub.10
straight-chained aliphatic monohydric alcohols, e.g., n-hexanol and
n-nonanol; diols such as ethylene glycol; polyols such as glycerin;
ethers such as diethylene glycol monoethyl ether; ketones such as
methyl ethyl ketone; esters such as methyl enanthate; and
hydrocarbons such as toluene. Preferably, the organic diluent is
sufficiently volatile to facilitate its removal from a cured
article by evaporation at or near ambient pressure. Generally, the
diluent is included at about 5 to about 60 percent by weight of the
monomeric mixture, with about 10 to about 50 percent by weight
being especially preferred.
[0059] The cured lens can then be subjected to solvent removal,
which can be accomplished by evaporation at or near ambient
pressure or under vacuum. An elevated temperature can be employed
to shorten the time necessary to evaporate the diluent. The time,
temperature and pressure conditions for the solvent removal step
will vary depending on such factors as the volatility of the
diluent and the specific monomeric components, as can be readily
determined by one skilled in the art. According to a preferred
embodiment, the temperature employed in the removal step is
preferably at least about 50.degree. C., for example, about
60.degree. C. to about 80.degree. C. A series of heating cycles in
a linear oven under inert gas or vacuum may be used to optimize the
efficiency of the solvent removal. The cured article after the
diluent removal step should contain no more than twenty percent by
weight of diluent, preferably no more than about 5 percent by
weight or less.
[0060] Following removal of the organic diluent, the lens can then
be subjected to mold release and optional machining operations. The
machining step includes, for example, buffing or polishing a lens
edge and/or surface. Generally, such machining processes may be
performed before or after the article is released from a mold part.
Preferably, the lens is dry released from the mold by employing
vacuum tweezers to lift the lens from the mold, after which the
lens is transferred by means of mechanical tweezers to a second set
of vacuum tweezers and placed against a rotating surface to smooth
the surface or edges. The lens may then be turned over in order to
machine the other side of the lens.
[0061] Next, the ophthalmic device such as a lens will be immersed
in an aqueous packaging solution and stored in a packaging system
according to the present invention. Generally, a packaging system
for the storage of an ophthalmic device according to the present
invention includes at least a sealed container containing one or
more unused ophthalmic devices immersed in an aqueous packaging
solution. Preferably, the sealed container is a hermetically sealed
blister-pack, in which a concave well containing an ophthalmic
device such as a contact lens is covered by a metal or plastic
sheet adapted for peeling in order to open the blister-pack. The
sealed container may be any suitable generally inert packaging
material providing a reasonable degree of protection to the lens,
preferably a plastic material such as polyalkylene, PVC, polyamide,
and the like.
[0062] The aqueous packaging solution will contain at least a
copolymer which is the reaction product of one or more
polymerizable polyhydric alcohols and one or more polymerizable
fluorine-containing monomers. The devices may either be unhydrated
or prehydrated in water or an aqueous solution. Suitable
polymerizable polyhydric alcohols include polyhydric alcohols
having one or more polymerizable ethylenically
unsaturated-containing radicals attached thereto. Representative
examples of a "polymerizable ethylenically unsaturated-containing
radical" include, by way of example, (meth)acrylate-containing
radicals, (meth)acrylamide-containing radicals,
vinylcarbonate-containing radicals, vinylcarbamate-containing
radicals, styrene-containing radicals, itaconate-containing
radicals, vinyl-containing radicals, vinyloxy-containing radicals,
fumarate-containing radicals, maleimide-containing radicals,
vinylsulfonyl radicals and the like. In one embodiment, a
polymerizable ethylenically unsaturated radical can be represented
by the general formula:
##STR00007##
wherein R.sup.8 is hydrogen or a alkyl group having 1 to 6 carbon
atoms such as methyl; each R.sup.9 is independently hydrogen, an
alkyl radical having 1 to 6 carbon atoms, or a --CO--Y--R.sup.11
radical wherein Y is --O--, --S-- or --NH-- and R.sup.11 is an
alkyl radical having 1 to about 10 carbon atoms; R.sup.10 is a
linking group (e.g., a divalent alkenyl radical having 1 to about
12 carbon atoms); B denotes --O-- or --NH--; Z denotes --CO--,
--OCO-- or --COO--; Ar denotes an aromatic radical having 6 to
about 30 carbon atoms; w is O to 6; a is O or 1; b is 0 or 1; and c
is 0 or 1. As used herein, the term "(meth)" denotes an optional
methyl substituent. Thus, for example, terms such as
"(meth)acrylate" denote either methacrylate or acrylate, and
"(meth)acrylamide" denotes either methacrylamide or acrylamide. The
ethylenically unsaturated-containing radicals can be attached to
the polyhydric alcohols as pendent groups, terminal groups or
both.
[0063] Representative examples of suitable polymerizable polyhydric
alcohols include polyhydroxyl (alk)acrylates having, for example, 2
to 10 hydroxyl groups and preferably 2 to 6 hydroxyl groups and an
alkyl group containing from 3 to 12 carbon atoms, polyhydroxyl
(alk)acrylamides having, for example, 2 to 10 hydroxyl groups and
preferably 2 to 6 hydroxyl groups and an alkyl group containing
from 3 to 12 carbon atoms and the like. Useful polyhydroxyl
(alk)acrylates include, but are not limited to, glycerol-containing
-acrylates -methacrylates, and -ethacrylates, sorbitol-containing
-acrylates, -methacrylates and -ethacrylates, erythritol-containing
-acrylates, -methacrylates, and -thacrylates, xylitol-containing
-acrylates, -methacrylates, -ethacrylates, derivatives thereof and
the like and mixtures thereof. Useful polyhydroxyl alk)acrylamides
include, but are not limited to, glycerol-containing -acrylamides,
-methacrylamides and -ethacrylamides, sorbitol-containing
-acrylamides, -methacrylamides and -ethacrylamides,
erythritol-containing -acrylamides, -methacrylamides and
-ethacrylamides, xylitol-containing -acrylamides, -methacrylamides
and -ethacrylamides, derivatives thereof and the like and mixtures
thereof.
[0064] Suitable fluorine-containing monomers include
fluorine-containing monomers having one or more polymerizable
ethylenically unsaturated-containing radicals attached thereto.
Representative examples of a "polymerizable ethylenically
unsaturated-containing radical" include, by way of example,
(meth)acrylate-containing radicals, (meth)acrylamide-containing
radicals, vinylcarbonate-containing radicals,
vinylcarbamate-containing radicals, styrene-containing radicals,
itaconate-containing radicals, vinyl-containing radicals,
vinyloxy-containing radicals, fumarate-containing radicals,
maleimide-containing radicals, vinylsulfonyl radicals and the like
and as exemplified for the polyhydric alcohol discussed above. The
ethylenically unsaturated-containing radicals can be attached to
the fluorine-containing monomer as pendent groups, terminal groups
or both. In one embodiment, useful polymerizable
fluorine-containing monomers include fluorine substituted
hydrocarbons having one or more polymerizable ethylenically
unsaturated-containing radicals attached thereto and optionally
containing one or more ether linkages, e.g., fluorine substituted
straight or branched C.sub.1-C.sub.18 alkyl groups having one or
more polymerizable ethylenically unsaturated-containing radicals
attached thereto which may include ether linkages therebetween;
fluorine substituted C.sub.3-C.sub.24 cycloalkyl groups having one
or more polymerizable ethylenically unsaturated-containing radicals
attached thereto which may include ether linkages therebetween and
fluorine substituted C.sub.6-C.sub.30 aryl groups having one or
more polymerizable ethylenically unsaturated-containing radicals
attached thereto which may include ether linkages therebetween.
[0065] Representative examples of alkyl groups for use herein
include, by way of example, a straight or branched hydrocarbon
chain radical containing carbon and hydrogen atoms of from 1 to
about 30 carbon atoms with or without unsaturation, to the rest of
the molecule, e.g., methyl, ethyl, n-propyl, 1-methylethyl
(isopropyl), n-butyl, n-pentyl, etc., and the like.
[0066] Representative examples of cycloalkyl groups for use herein
include, by way of example, a substituted or unsubstituted
non-aromatic mono or multicyclic ring system of about 3 to about 24
carbon atoms such as, for example, cyclopropyl, cyclobutyl,
cyclopentyl, cyclohexyl, perhydronapththyl, adamantyl and norbornyl
groups bridged cyclic group or sprirobicyclic groups, e.g.,
sprio-(4, 4)-non-2-yl and the like, optionally containing one or
more heteroatoms, e.g., O and N, and the like.
[0067] Representative examples of aryl groups for use herein
include, by way of example, a substituted or unsubstituted
monoaromatic or polyaromatic radical containing from about 5 to
about 30 carbon atoms such as, for example, phenyl, naphthyl,
tetrahydronapthyl, indenyl, biphenyl and the like, optionally
containing one or more heteroatoms, e.g., O and N, and the
like.
[0068] Examples of such polymerizable fluorine-containing monomer
include, but are not limited to,
2,2,2-trifluoroethyl(meth)acrylate,
2,2,3,3-tetrafluoropropyl(meth)acrylate,
2,2,3,3,3,-pentafluoropropyl(meth)acrylate,
1-trifluoromethyl-2,2,2-trifluoroethyl (meth)acrylate, 1H,
1H,5H-octafluoropentyl(meth)acrylate, hexafluoroisopropyl
(meth)acrylate, 2,2,3,3,4,4-hexafluorobutyl(meth)acrylate,
pentafluorophenyl(meth)acrylate, pentafluorohexyl(meth)acrylate and
mixtures thereof.
[0069] The copolymers disclosed herein can be obtained by
copolymerizing the mixture containing at least one or more
polymerizable polyhydric alcohols and one or more polymerizable
fluorine-containing monomers by conventional techniques for
polymerization, typically thermal or photochemical polymerization.
For thermal polymerization, microwave radiation may be used. The
temperature employed during thermal polymerization can range from
about 40.degree. C. to about 120.degree. C., and typically about
50.degree. C. to about 100.degree. C. is used. For photochemical
polymerization, radiation such as gamma, ultraviolet (UV) or
visible, may be used.
[0070] Polymerization is generally performed in a reaction medium
such as, for example, a solution or dispersion using a solvent,
e.g., water, an alkanol containing from 1 to 12 carbon atoms such
as methanol, ethanol, isopropanol, propan-2-ol, t-butanol, t-amyl
alcohol, n-hexanol, nonanol and the like, cyclic ethers such as
tetrahydrofuran and the like, aromatic hydrocarbons such as toluene
and the like. Alternatively, a mixture of any of the above solvents
may be used.
[0071] A polymerization initiator may be included in the mixture to
facilitate the polymerization step. Representative free radical
thermal polymerization initiators are usually peroxides or azo
initiators such as, for example, acetal peroxide, lauroyl peroxide,
decanoyl peroxide, stearoyl peroxide, benzoyl peroxide,
tertiarylbutyl peroxypivalate, peroxydicarbonate,
2,2'-azo-bis(2-methylpropionitrile), benzoin methyl ether and the
like and mixtures thereof. Representative UV initiators are those
known in the field such as, for example, benzoin methyl ether,
benzoin ethyl ether, Darocure 1173, 1164, 2273, 1116, 2959, 3331
(EM Industries) and Igracure 651 and 184 (Ciba-Geigy), and the like
and mixtures thereof. Other polymerization initiators which may be
used are disclosed in, for example, "Polymer Handbook", 4th
edition, Ed. J. Brandrup, E. H. Immergut, E. A. Grulke, A. Abe and
D. R. Bloch, Pub. Wiley-Interscience, New York, 1998. Generally,
the initiator will be employed in the mixture at a concentration at
about 0.1 to about 5 percent by weight of the total mixture.
[0072] Generally, polymerization can be carried out for about 1 to
about 72 hours and under an inert atmosphere of, for example,
nitrogen or argon. If desired, the resulting polymer can be dried
under vacuum, e.g., for about 5 to about 72 hours or left in an
aqueous solution prior to use. The resulting polymerization product
can have a number average molecular weight from about 500 to about
500,000 and preferably from about 1,000 to about 200,000.
[0073] The precise proportion and nature of the various comonomers
used in the mixture to prepare a copolymer disclosed herein may be
adjusted to provide a copolymer which is particularly suitable for
treating the surface of the device according to the present
invention. The mixture which is subjected to polymerization to
provide a polymerization product according to the invention can
contain a minimum of about 10%, and preferably about 30% to about
80% by weight of one or more polymerizable polyhydric alcohols and
a maximum of about 50%, and preferably about 10% to about 30% by
weight of one or more polymerizable fluorine-containing
monomers.
[0074] If desired, the copolymer can be endcapped with a suitable
endcapping group as known in the art. Examples of a suitable
end-capping group include isocyanatoethyl methacrylate ("IEM"),
methacrylic anhydride, methacryloyl chloride, vinylbenzoyl
chloride, and the like, to produce a copolymer having one or more
terminal polymerizable olefinic groups bonded to the copolymer
through linking moieties such as carbamate or ester groups.
[0075] The amount of the copolymer employed in a packaging solution
for storing an ophthalmic device in a packaging system of the
present invention is an amount effective to improve the surface
properties of the ophthalmic device. Generally, the concentration
of a hydrophilic polymer present in the packaging solution of the
invention will range from about 0.01 to about 10% w/w.
[0076] The packaging solutions according to the present invention
are physiologically compatible. Specifically, the solution must be
"ophthalmically safe" for use with a lens such as a contact lens,
meaning that a contact lens treated with the solution is generally
suitable and safe for direct placement on the eye without rinsing,
that is, the solution is safe and comfortable for daily contact
with the eye via a contact lens that has been wetted with the
solution. An ophthalmically safe solution has a tonicity and pH
that is compatible with the eye and includes materials, and amounts
thereof, that are non-cytotoxic according to ISO standards and U.S.
Food & Drug Administration (FDA) regulations.
[0077] The packaging solution should also be sterile in that the
absence of microbial contaminants in the product prior to release
must be statistically demonstrated to the degree necessary for such
products. The liquid media useful in the present invention are
selected to have no substantial detrimental effect on the lens
being treated or cared for and to allow or even facilitate the
present lens treatment or treatments. The liquid media are
preferably aqueous-based. A particularly useful aqueous liquid
medium is that derived from saline, for example, a conventional
saline solution or a conventional buffered saline solution.
[0078] The pH of the present solutions should be maintained within
the range of about 6 to about 9, and preferably about 6.5 to about
7.8. Suitable buffers may be added, such as boric acid, sodium
borate, potassium citrate, citric acid, sodium bicarbonate, TRIS
and various mixed phosphate buffers (including combinations of
Na.sub.2 HPO.sub.4, NaH.sub.2 PO.sub.4 and KH.sub.2 PO4) and
mixtures thereof. Generally, buffers will be used in amounts
ranging from about 0.05 to about 2.5 percent by weight, and
preferably from about 0.1 to about 1.5 percent by weight of the
solution. The packaging solutions of this invention preferably
contain a borate buffer, containing one or more of boric acid,
sodium borate, potassium tetraborate, potassium metaborate or
mixtures of the same.
[0079] Typically, the solutions of the present invention are also
adjusted with tonicity agents, to approximate the osmotic pressure
of normal lacrimal fluids which is equivalent to a 0.9 percent
solution of sodium chloride or 2.5 percent of glycerol solution.
The solutions are made substantially isotonic with physiological
saline used alone or in combination, otherwise if simply blended
with sterile water and made hypotonic or made hypertonic the lenses
will lose their desirable optical parameters. Correspondingly,
excess saline may result in the formation of a hypertonic solution
which will cause stinging and eye irritation.
[0080] Examples of suitable tonicity adjusting agents include, but
are not limited to, sodium and potassium chloride, dextrose,
glycerin, calcium and magnesium chloride and the like and mixtures
thereof. These agents are typically used individually in amounts
ranging from about 0.01 to about 2.5% w/v and preferably from about
0.2 to about 1.5% w/v. Preferably, the tonicity agent will be
employed in an amount to provide a final osmotic value of at least
about 200 mOsm/kg, preferably from about 200 to about 400 mOsm/kg,
more preferably from about 250 to about 350 mOsm/kg, and most
preferably from about 280 to about 320 mOsm/kg.
[0081] If desired, one or more additional components can be
included in the packaging solution. Such additional component or
components are chosen to impart or provide at least one beneficial
or desired property to the packaging solution. Such additional
components may be selected from components which are conventionally
used in one or more ophthalmic device care compositions. Examples
of such additional components include cleaning agents, wetting
agents, nutrient agents, sequestering agents, viscosity builders,
contact lens conditioning agents, antioxidants, and the like and
mixtures thereof. These additional components may each be included
in the packaging solutions in an amount effective to impart or
provide the beneficial or desired property to the packaging
solutions. For example, such additional components may be included
in the packaging solutions in amounts similar to the amounts of
such components used in other, e.g., conventional, contact lens
care products.
[0082] Useful sequestering agents include, but are not limited to,
disodium ethylene diamine tetraacetate, alkali metal
hexametaphosphate, citric acid, sodium citrate and the like and
mixtures thereof.
[0083] Useful viscosity builders include, but are not limited to,
hydroxyethyl cellulose, hydroxymethyl cellulose, polyvinyl
pyrrolidone, polyvinyl alcohol and the like and mixtures
thereof.
[0084] Useful antioxidants include, but are not limited to, sodium
metabisulfite, sodium thiosulfate, N-acetylcysteine, butylated
hydroxyanisole, butylated hydroxytoluene and the like and mixtures
thereof.
[0085] The method of packaging and storing an ophthalmic device
such as a contact lens according to the present invention includes
at least packaging an ophthalmic device immersed in the aqueous
packaging solution described above. The method may include
immersing the ophthalmic device in an aqueous packaging solution
prior to delivery to the customer/wearer, directly following
manufacture of the contact lens. Alternately, the packaging and
storing in the solution of the present invention may occur at an
intermediate point before delivery to the ultimate customer
(wearer) but following manufacture and transportation of the lens
in a dry state, wherein the dry lens is hydrated by immersing the
lens in the packaging solution. Consequently, a package for
delivery to a customer may include a sealed container containing
one or more unused contact lenses immersed in an aqueous packaging
solution according to the present invention.
[0086] In one embodiment, the steps leading to the present
ophthalmic device packaging system includes (1) molding an
ophthalmic device in a mold comprising at least a first and second
mold portion, (2) hydrating and cleaning the device in a container
comprising at least one of the mold portions, (3) introducing the
packaging solution with the copolymer into the container with the
device supported therein, and (4) sealing the container.
Preferably, the method also includes the step of sterilizing the
contents of the container. Sterilization may take place prior to,
or most conveniently after, sealing of the container and may be
effected by any suitable method known in the art, e.g., by
autoclaving of the sealed container at temperatures of about
120.degree. C. or higher.
[0087] The following examples are provided to enable one skilled in
the art to practice the invention and are merely illustrative of
the invention. The examples should not be read as limiting the
scope of the invention as defined in the claims.
[0088] ID2S4H: A methacrylate-capped prepolymer derived from
isophorone diisocyanate, diethylene glycol and
a,o)-bis-hydroxybutyl polydimethylsiloxane of Mn 4000 at a molar
ratio of 6: 3:2 and end-capped with 2-hydroxyethyl
methacrylate.
[0089] TRIS: tris(trimethylsiloxy)silylpropyl methacrylate
[0090] NVP: N-vinyl-2-pyrrolidone
[0091] DMA: N,N-dimethyl acrylamide
[0092] HEMA: 2-hydroxyethyl methacrylate
[0093] HEMAVC: methacryloxyethyl vinyl carbonate
[0094] D1173: 2-hydroxy-2-methyl-1-phenylpropan-1-one (available as
Darocur 1173 initiator)
[0095] IMVT:
1,4-bis(4-(2-methacryloxyethyl)phenylamino)anthraquinone
[0096] PP: polypropylene
[0097] THF: tetrahydrofuran
[0098] AIBN: azo bis-isobutylnitrile (commercially available as
Vazo.TM. 64)
[0099] DBTDL: dibutyltin dilaurate
[0100] IPA: isopropyl alcohol
EXAMPLE 1
[0101] Synthesis of Poly(glyceryl methacrylate-co-octafluoropentyl
methacrylate) ("P(GM-co-OFPMA)").
[0102] To a three-neck 500 liter flask equipped with condenser and
nitrogen inlet tube was added glyceryl methacrylate (9.724 g;
60.711 mmol), THF (200 ml), 1H, 1H, 5H-octafluropentyl methacrylate
(4.481 g; 14.927 mmol), and AIBN (0.214 g; 1.303 mmol). The
contents were bubbled vigorously with nitrogen for 20 minutes and
then heated to reflux under the constant nitrogen flow overnight. A
white product precipitated on the second day. The product was
recovered by removal of solvent.
EXAMPLE 2
[0103] Preparation of lens.
[0104] Monomer mixtures are made by mixing the following components
listed in Table 1, at amounts per weight.
TABLE-US-00001 TABLE 1 Amount in Ingredient weight ID2S4H 11 TRIS
35 DMA 10 NVP 40 HEMAVC 1 3-methoxy-1-butanol 4 Vazo-64 0.5
Glycidyl methacrylate 5 IMVT 150 ppm
The resultant monomer mixtures are cast into contact lenses by
introducing the monomer mixture to a mold assembly composed of a PP
mold for the anterior surface and a PP mold for the posterior
surface and thermally curing the monomer mixture at 100.degree. C.
for 2 hours. The contact lenses are released from the molds.
EXAMPLE 3
[0105] An aqueous packaging solution containing 1% by weight of the
copolymer of Example 1 dissolved in a borate buffered saline at a
pH of 7.2 is placed in a polypropylene blister package. Next, the
lenses of Example 2 are immersed in the aqueous packaging solution
in the polypropylene blister package. The package is sealed with
foil lidstock and then autoclaved for 1 cycle.
EXAMPLE 4
[0106] Preparation of isocyanatoethyl methacrylate functionalized
Poly(glyceryl methacrylate-co-octafluoropentyl methacrylate).
[0107] To a three-neck 100 ml flask equipped with condenser, and
nitrogen inlet tube, was added glyceryl methacrylate (2.746 g;
17.146 mmol), methanol (50 ml), 1H, 1H, 5H-octafluoropentyl
methacrylate (1.261 g; 4.199 mmol), and AIBN (0.068 g; 0.414 mmol).
The contents were bubbled with nitrogen vigorously for 20 minutes.
Next, the mixture was heated under reflux with constant nitrogen
flow for two days. The solvent was then removed first under reduced
pressure and then under high vacuum for 3 hours to provide a white
polymer solid. Anhydrous THF (50 ml) was transferred to the flask
containing the white polymer solid under the flowing of dry
nitrogen and then DBTDL (0.04 g) and isocyanatoethyl methacrylate
((0.6585 g; (4.244 mmol)) were added to the flask. The contents
were then stirred at room temperature for two days under nitrogen
purging. The solution was then dialyzed in 2500 ml 50/50 IPA/water
solution using a cellulose ester dialysis film with a cut off
number average molecular weight of 500 for 6 days. The macro
monomer product was recovered by removing the solvent.
EXAMPLE 5
[0108] Preparation of lens.
[0109] Monomer mixtures are made by mixing the following components
listed in Table 2, at amounts per weight.
TABLE-US-00002 TABLE 2 Amount in Ingredient weight ID2S4H 11 TRIS
35 DMA 10 NVP 40 HEMAVC 1 3-methoxy-1-butanol 4 Vazo-64 0.5
Glycidyl methacrylate 5 IMVT 150 ppm
The resultant monomer mixtures are cast into contact lenses by
introducing the monomer mixture to a mold assembly composed of a PP
mold for the anterior surface and a PP mold for the posterior
surface and thermally curing the monomer mixture at 100.degree. C.
for 2 hours. The contact lenses are released from the molds.
EXAMPLE 6
[0110] An aqueous packaging solution containing 1% by weight of the
macro monomer of Example 4 dissolved in a borate buffered saline at
a pH of 7.2 is placed in a polypropylene blister package. Next, the
lenses of Example 5 are immersed in the aqueous packaging solution
in the polypropylene blister package. The package is sealed with
foil lidstock and then autoclaved for 1 cycle.
EXAMPLE 7
[0111] An aqueous packaging solution containing 1% by weight of the
copolymer of Example 1 dissolved in a borate buffered saline at a
pH of 7.2 is placed in a polypropylene blister package. Next, a
balafilcon A contact lens (a commercially available group III
extended wear contact lenses from Bausch & Lomb Incorporated of
Rochester, N.Y., sold under the trade name Purevision.RTM., made of
a silicone hydrogel material and having an anionic charge and
approximately 38% water) is immersed in the aqueous packaging
solution in the polypropylene blister package. The package is
sealed with foil lidstock and then autoclaved for 1 cycle.
EXAMPLE 8
[0112] An aqueous packaging solution containing 1% by weight of the
macro monomer of Example 4 dissolved in a borate buffered saline at
a pH of 7.2 is placed in a polypropylene blister package. Next, a
balafilcon A contact lens (a commercially available group III
extended wear contact lenses from Bausch & Lomb Incorporated of
Rochester, N.Y., sold under the trade name Purevision.phi., made of
a silicone hydrogel material and having an anionic charge and
approximately 38% water) is immersed in the aqueous packaging
solution in the polypropylene blister package. The package is
sealed with foil lidstock and then autoclaved for 1 cycle.
EXAMPLE 9
[0113] An aqueous packaging solution containing 2% by weight of the
copolymer of Example 1 dissolved in a borate buffered saline at a
pH of 7.2 is placed in a polypropylene blister package. Next, a
balafilcon A contact lens (a commercially available group III
extended wear contact lenses from Bausch & Lomb Incorporated of
Rochester, N.Y., sold under the trade name Purevision.RTM., made of
a silicone hydrogel material and having an anionic charge and
approximately 38% water) is immersed in the aqueous packaging
solution in the polypropylene blister package. The package is
sealed with foil lidstock and then autoclaved for 1 cycle.
EXAMPLE 10
[0114] An aqueous packaging solution containing 2% by weight of the
macro monomer of Example 4 dissolved in a borate buffered saline at
a pH of 7.2 is placed in a polypropylene blister package. Next, a
balafilcon A contact lens (a commercially available group III
extended wear contact lenses from Bausch & Lomb Incorporated of
Rochester, N.Y., sold under the trade name Purevision.RTM., made of
a silicone hydrogel material and having an anionic charge and
approximately 38% water) is immersed in the aqueous packaging
solution in the polypropylene blister package. The package is
sealed with foil lidstock and then autoclaved for 1 cycle.
[0115] It will be understood that various modifications may be made
to the embodiments disclosed herein. Therefore the above
description should not be construed as limiting, but merely as
exemplifications of preferred embodiments. For example, the
functions described above and implemented as the best mode for
operating the present invention are for illustration purposes only.
Other arrangements and methods may be implemented by those skilled
in the art without departing from the scope and spirit of this
invention. Moreover, those skilled in the art will envision other
modifications within the scope and spirit of the features and
advantages appended hereto.
* * * * *