BACKGROUND OF THE INVENTION
1. Field of the Invention
[0001] The instant disclosure relates to a composition for contact lenses; in particular,
to a composition for contact lenses which can serve as a contact lens preservation
solution.
2. Description of Related Art
[0002] Smartphones and computers are used frequently in today's information society, resulting
in an increase in the population with myopia and a decrease in the age group of myopia.
In consideration of user convenience and aesthetics, it is generally a good choice
for people with myopia to wear contact lenses. However, most people with myopia need
to wear contact lenses for extended periods of time. Although the material of the
conventional contact lenses have been constantly improved to meet various requirements
such as high water content and high oxygen permeability, the wearers thereof would
still suffer from eye dryness due to decreased water content and experience eye discomfort
due to dirt or secretion. Therefore, there is an urgent need for a maintenance solution
that can be used to clean, rehydrate and preserve contact lenses.
SUMMARY OF THE INVENTION
[0003] One aspect of the instant disclosure relates to a composition for contact lens which
allows a contact lens wearer's eyes to feel comfortable during the period of initial
wear and extended periods of continuous wear.
[0004] According to one of the embodiments of the instant disclosure, the composition for
contact lenses includes an algefacient and a surfactant, wherein the surfactant includes
one or a combination of sodium lauroyl lactylate, polyoxyethylene laureth sulfate,
polyoxyethylene hardened castor oil, polyvinylpyrrolidone (PVP), sodium dodecyl sulfate
(SDS), TWEEN 80™ and GEROPON™ SBFA-30.
[0005] Based on the above, by cooperatively using the algefacient and the surfactant, wherein
the surfactant includes one or a combination of sodium lauroyl lactylate, polyoxyethylene
laureth sulfate, polyoxyethylene hardened castor oil, polyvinylpyrrolidone (PVP),
sodium dodecyl sulfate (SDS), TWEEN 80™ and GEROPON™ SBFA-30, the expression of the
algefacient in the composition of a contact lens can be performed effectively. Therefore,
the discomfort and foreign matter sensation in the eyes of contact lens wearers can
be reduced or relieved, providing long-lasting cool and moist sensations to the eyes.
[0006] In order to further appreciate the characteristics and technical contents of the
instant disclosure, references are hereunder made to the detailed descriptions and
appended drawings in connection with the instant disclosure. However, the appended
drawings are merely shown for exemplary purposes, rather than being used to restrict
the scope of the instant disclosure.
BRIEF DESCRIPTION OF THE DRAWINGS
[0007] Fig. 1 is a perspective view showing a contact lens and a composition for contact
lenses according to the instant disclosure in a container.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0008] The aforementioned illustrations and following detailed descriptions are exemplary
for the purpose of further explaining the scope of the instant disclosure. Other objectives
and advantages related to the instant disclosure will be illustrated in the subsequent
descriptions and appended drawings.
[0009] Referring to FIG. 1, the instant disclosure provides a composition for contact lenses
which can serve as a preservation solution and be hermetically sealed with the contact
lenses in a container. In practice, the contact lenses are immersed in direct contact
with the composition. When the user wishes to wear the contact lenses, the user takes
the contact lens out of the composition and put the contact lenses on his/her eyes.
More specifically, the ingredients of the composition absorb onto the surface of the
contact lenses and then transfer into the user's eyes.
[0010] The composition according to the instant embodiment is intended for use in connection
with soft and rigid contact lenses. The term "soft contact lens" can refer to a hydrous
soft contact lens made from hydrogels (i.e., hydrogel contact lenses) and a non-hydrous
soft contact lens made from copolymers of butyl acrylate and butyl methacrylate. Furthermore,
the composition according to the instant embodiment is applicable to the soft contact
lenses in U.S. FDA category Group I-IV. Group I-IV lenses often contain materials
identified in the market as: alphafilcon, asmofilcon, balafilcon, ethafilcon, hefilcon,
hilafilcon, lidofilcon, lotrafilcon, methafilcon, nelfilcon, ocufilcon, omafilcon,
phemfilcon, polymacon, tefilcon, tetrafilcon, vasurfilcon, vifilcon, senofilcon, galyfilcon,
enfilcon, comfilcon, narafilcon, delefilcon, efrofilcon, and filicon II 3.
[0011] The composition according to the instant embodiment mainly includes a base solution,
an algefacient, a surfactant, and a water soluble polymer. The algefacient, the surfactant,
and the water soluble polymer are uniformly dispersed in the base solution.
[0012] In the instant embodiment, the base solution is a physiological saline solution with
a buffer containing boric acid or phosphorous acid. The buffer has a pH buffering
capacity and is configured to adjust the pH of the composition to a pH between 6.8
and 7.6. In addition, the base solution can include an appropriate amount of sodium
chloride or potassium chloride to maintain the osmolality of the composition at a
value between 250 Osmol/Kg and 350 Osmol/Kg.
[0013] The buffer can be selected from boric acid, borate (e.g., sodium tetraborate), phosphorous
acid, or phosphate (e.g., sodium hydrogen phosphate and sodium dihydrogen phosphate).
It should be noted that a buffer may be used alone or two or more different buffers
may be used in combination in the base solution. In addition, the concentration of
the buffer may be appropriately adjusted depending on its kind or the kind of the
other ingredients.
[0014] The algefacient is added to reduce or relieve the discomfort and foreign matter sensation
in the eyes and give the eyes a cool, fresh sensation. The algefacient includes one
or a combination of menthol, camphor, borneol, menthyl lactate, menthone glycerol
ketal, monomethyl succinate, and p-menthane-3,8-doil. The content of the algefacient
is in the range between 0.001% (w/v) and 0.5 % (w/v), preferably between 0.001% (w/v)
and 0.25 % (w/v), to avoid irritating the eye.
[0015] The surfactant is added to clean and moisturize a contact lens, in which protein
and lipid deposits on the surfaces of the contact lens can be removed. The surfactant
includes one or a combination of sodium lauroyl lactylate, polyoxyethylene laureth
sulfate, polyoxyethylene hardened castor oil, polyvinylpyrrolidone (PVP), sodium dodecyl
sulfate (SDS), TWEEN 80TM and GEROPONTM SBFA-30. The content of the surfactant is
in the range between 0.001% (w/v) and 2% (w/v), and preferably between 0.001% (w/v)
and 0.5 % (w/v).
[0016] It should be noted that by cooperatively using the algefacient and the surfactant,
the expression of the algefacient in the composition for contact lenses can be performed
effectively. Therefore, eye related symptoms such as eye fatigue, eye dryness, eye
pruritus, and eye pain can be reduced or relieved, and a cool fresh sensation in the
eyes can be maintained for a long period of time.
[0017] The water soluble polymer is added to moisten and lubricate the eyes, and also helps
to keep the ingredients beneficial to the eyes in contact with the contact lens. For
example, if the composition for contact lenses includes one or more vitamins (e.g.,
A, B and E), the vitamin(s) can be attached to the surface of the contact lens by
interacting with the water soluble polymer. The water soluble polymer includes one
or a combination of polyethylene glycol 400 (PEG 400), methacryloyloxyethyl phosphorylcholine
(MPC), and hyaluronic acid. Exemplarily, the water soluble polymer includes PEG 400
and MPC in a molar ratio of 1:20. The content of the water soluble polymer is in the
range between 0.05% (w/v) and 5% (w/v).
[0018] Examples 1-5 and Comparative Examples 1-2 are shown in Table 1. Each of the compositions
obtained respectively in Examples 1-5 and Comparative Examples 1-2 was used in full
contact with the contact lenses. The contact lenses were then put on the user's eyes,
and a VAS (Visual analogue scale) method was used to evaluate the sensations of lubrication,
comfort, coolness, and moisture in the eyes during the period of initial wear (time
1) and after wearing for 30 minutes (time 2) and 60 minutes (time 3). The evaluation
results of for the Examples 1-5 and the Comparative Examples 1-2 are shown in Table
2. Scores for each of the items, as shown in Table 2, are average scores calculated
from three users (i.e., six eyes).
Table 1
|
unit: g |
Examples |
Comparative ex |
1 |
2 |
3 |
4 |
5 |
1 |
2 |
water |
2000 |
2000 |
2000 |
2000 |
2000 |
2000 |
2000 |
sodium chloride |
10-20 |
10-20 |
10-20 |
10-20 |
10-20 |
10-20 |
10-20 |
boric acid |
8-16 |
8-16 |
8-16 |
8-16 |
8-16 |
8-16 |
8-16 |
sodium tetraborate |
0.5-4.5 |
0.5-4.5 |
0.5-4.5 |
0.5-4.5 |
0.5-4.5 |
0.5-4.5 |
0.5-4.5 |
TWEEN 80™ |
0.01-5 |
0.01-5 |
- |
0.01-5 |
0.01-5 |
- |
- |
PVP |
0.01-5 |
0.01-5 |
0.01-5 |
0 |
0.01-5 |
- |
- |
GEROPON™ SBFA-30 |
0 |
0.01-5 |
0.01-5 |
0 |
0.01-5 |
- |
- |
polyoxyethylene hardened castor oil |
- |
- |
- |
0.01-2.5 |
0.01-2.5 |
- |
- |
Hyaluronic acid (HA) |
0-50 |
0-50 |
0-50 |
0-50 |
0-50 |
- |
0-50 |
PEG400 |
0-50 |
0-50 |
0-50 |
0-50 |
0-50 |
- |
0-50 |
MPC |
0-50 |
0-50 |
0-50 |
0-50 |
0-50 |
- |
0-50 |
menthol |
0-4 |
0-4 |
0-4 |
0-4 |
0-4 |
- |
0-4 |
camphor |
0-4 |
0-4 |
0-4 |
0-4 |
0-4 |
- |
0-4 |
borneol |
0-4 |
0-4 |
0-4 |
0-4 |
0-4 |
- |
0-4 |
menthyl lactate |
0-4 |
0-4 |
0-4 |
0-4 |
0-4 |
- |
0-4 |
menthone-glycerol ketal |
0-4 |
0-4 |
0-4 |
0-4 |
0-4 |
- |
0-4 |
monomethyl succinate |
0-4 |
0-4 |
0-4 |
0-4 |
0-4 |
- |
0-4 |
p-menthane-3,8-doil |
0-4 |
0-4 |
0-4 |
0-4 |
0-4 |
- |
0-4 |
Table 2
evaluation items |
wear-in time |
self-feeling score |
Examples |
Comparative ex |
lubrication sensation |
immediately right after |
7 |
8 |
after 30 minutes |
7 |
8 |
after 60 minutes |
6 |
8 |
comfort sensation |
immediately right after |
7 |
8 |
after 30 minutes |
7 |
8 |
after 60 minutes |
7 |
8 |
coolness sensation |
immediately right after |
NA |
9 |
after 30 minutes |
NA |
6 |
after 60 minutes |
NA |
4 |
moisture sensation |
immediately right after |
8 |
10 |
after 30 minutes |
8 |
9 |
after 60 minutes |
8 |
9 |
[0019] The composition for contact lenses in which the algefacient and the surfactant are
cooperatively used and the surfactant includes one or a combination of sodium lauroyl
lactylate, polyoxyethylene laureth sulfate, polyoxyethylene hardened castor oil, polyvinylpyrrolidone
(PVP), sodium dodecyl sulfate (SDS), TWEEN 80™ and GEROPON™ SBFA-30. Accordingly,
the expression of the algefacient can be performed effectively, so that the discomfort
and foreign matter sensation in the eyes of contact lens wearers can be reduced or
relieved, and long-lasting cool and moist sensations can be provided to the eyes.
[0020] The descriptions illustrated
supra set forth simply the preferred embodiments of the instant disclosure; however, the
characteristics of the instant disclosure are by no means restricted thereto. All
changes, alternations, or modifications conveniently considered by those skilled in
the art are deemed to be encompassed within the scope of the instant disclosure delineated
by the following claims.
1. A composition for contact lenses which includes an algefacient and a surfactant, wherein
the surfactant includes one or a combination of sodium lauroyl lactylate, polyoxyethylene
laureth sulfate, polyoxyethylene hardened castor oil, polyvinylpyrrolidone (PVP),
sodium dodecyl sulfate (SDS), TWEEN 80™ and GEROPON™ SBFA-30.
2. The composition for contact lens according to claim 1, wherein the content of the
surfactant is in the range between 0.001% (w/v) and 0.5% (w/v).
3. The composition for contact lens according to claim 1, wherein the algefacient includes
one or a combination of menthol, camphor, borneol, menthyl lactate, menthone glycerol
ketal, monomethyl succinate, and p-menthane-3,8-doil.
4. The composition for contact lens according to claim 3, wherein the algefacient is
menthol.
5. The composition for contact lens according to claim 3 or 4, wherein the content of
the algefacient is in the range between 0.001% (w/v) and 0.25 % (w/v).
6. The composition for contact lens according to claim 1, further including a water soluble
polymer, wherein the water soluble polymer includes one or a combination of polyethylene
glycol 400 (PEG 400), methacryloyloxyethyl phosphorylcholine (MPC), and hyaluronic
acid.
7. The composition for contact lens according to claim 6, wherein the water soluble polymer
includes PEG 400 and MPC in a molar ratio of 1:20.
8. The composition for contact lens according to claim 6 or 7, wherein the content of
the water soluble polymer is in the range between 0.05% (w/v) and 5% (w/v).
9. The composition for contact lens according to claim 1, further including a buffer,
wherein the buffer includes boric acid and sodium tetraborate.