Note: Descriptions are shown in the official language in which they were submitted.
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CONTACT LENS COMPRISING A TURQUOISE COLORANT
RELATED APPLICATIONS
This application claims the benefit under 35 U.S.C. ~ 119(e) of the filing
date of the provisional U.S. patent application having serial number
60/174,288, filed on January 3, 2000, which is hereby incorporated by
reference.
BACKGROUND OF THE INVENTION
Over the years, many attempts have been made to modify or change
the appearance of color of one's eyes using colored contact lenses with
varying degrees of success. Attempts to produce an opaque lens with a
natural appearance are disclosed in. U.S. Pat. Nos. 3,536,386, (Spivak);
3,679,504 (Wichterle); 3,712,718 (LeGrand), 4,460,523 (Neefe), 4,719,657
(Bawa), 4,744,647, (Meshel et al.), 4,634,449 (Jenkins); European Patent
Publication No. 0 309 154 (Allergan) and U.K. Patent Application No. 2 202
540 A (IGEL).
Commercial success was achieved by the colored contact lens
described in Knapp (in U.S. Pat. No. 4,582,402), which discloses a contact
lens having, in its preferred embodiment, colored, opaque dots. The Knapp
lens provides a natural appearance with a lens that is simple and inexpensive
to produce, using a simple one-color printed dot pattern. Although, in Knapp,
the intermittent pattern of dots does not fully cover the iris, the invention
provides a sufficient density of dots that a masking effect gives the
appearance of a continuous color when viewed by an ordinary observer.
Knapp also discloses that the printing step may be repeated one or more-
times using different patterns in different colors, since upon close
examination
the iris's of many persons are found to contain more than one color.
The printed pattern need not be absolutely uniform, allowing for the
change or modification of the appearance of the fine structure of the iris.
The
one-color Knapp lenses currently achieving commercial success have their
dots arranged in an irregular pattern to enhance the structure of the iris.
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However, neither the Knapp commercial lenses, nor the ICnapp patent
disclose or suggest a contact lens in which the color and design combine to
change a person's eyes to a striking turquoise color.
Other attempts to create a more natural appearing lens include U.S.
Pat. No. 5,120,121 to Rawlings, which discloses a cluster of interconnecting
lines radiating from the periphery of the pupil portion to the periphery of
the
iris portion. Further, European Patent No. 0 472 496 A2 shows a contact lens
having a pattern of lines that attempts to replicate the lines found in the
iris.
Although many attempts have been made to create colored contact
lenses that change or modify the appearance of color of the iris, none of the
colored contact lenses have addressed changing or modifying the '
appearance of the contact wearer's eyes so that they appear to be a natural,
striking, turquoise color.
SUMMARY OF THE INVENTION
In one aspect of the invention, a colored contact lens is provided. The
confiact lens comprises a pupil section and an iris section surrounding the
pupil section wherein the iris section is at least partly covered by a
turquoise
colorant having a blue component, a green component, a titanium dioxide
component, and a violet component.
In another aspect of the invention, a contact lens is provided that is
worn by a person to change the appearance of a human iris to a turquoise
color. The contact lens comprises a non-opaque pupil section, an iris section
surrounding said pupil section, and a colored, opaque intermittent pattern
over
said iris section that leaves a substantial portion of the pattern non-opaque,
said pattern covering at least about 25% of the area of said iris section, the
elements of said pattern being indiscernible to the ordinary viewer, said
pattern being made up of a turquoise colorant, a hazel colorant, and a dark
colorant.
In still another aspect of the invention, a contact lens comprises a non-
opaque pupil section, an iris section surrounding said pupil section, and at
feast two colored, opaque intermittent patterns over said iris section that
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leaves a substantial portion of the pattern non-opaque, said patterns covering
at least about 25% of the area of said iris section, wherein the elements of a
first pattern comprise turquoise colorant and the elements of a second pattern
comprise hazel colorant.
The term "non-opaque" as used herein is intended to describe a part of
the lens that is uncolored or colored with translucent coloring.
The term "ordinary viewer" is intended to mean a person having normal
20-20 vision standing about 5 feet from a person wearing the lenses of this
invention.
BRIEF DESCRIPTION OF THE DRAWINGS
Figure 1 illustrates a contact lens having a pupil section and an iris
section.
Figure 2 illustrates an outermost starburst pattern for use on a contact
lens.
Figure 3 illustrates an outer starburst pattern for use on a contact lens.
Figure 4 illustrates an inner starburst pattern for use on a contact lens.
Figure 5 illustrates a graph of reflectance versus wavelength of the
turquoise colorant on a contact lens.
Figure 6 illustrates a graph of reflectance versus wavelength of a hazel
colorant on a contact lens.
Figure 7 illustrates a graph of reflectance versus wavelength of a black
colorant on a contact lens.
DETAILED DESCRIPTION OF THE DRAWINGS AND THE
PREFERRED EMBODIMENTS OF THE INVENTION
Figure 1 shows a contact lens 10. It has a non-opaque pupil section 20
in the center of the lens, and an annular iris section 22 surrounding the
pupil
section. For hydrophilic lenses a peripheral section surrounds iris section
22.
A colored, opaque, intermittent pattern is located over the iris section 22,
as
shown in Figure 1. The pattern leaves a substantial portion of the iris
section
within the interstices of the pattern non-opaque. The non-opaque areas of the
iris section 22 appear white in Figure 1.
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The elements of the pattern are preferably dots, and especially
preferred are dots, some of which run together, as shown in Figure 1. Certain
portions of the iris section 22 are less densely covered with dots than other
portions.
The opaque pattern or patterns can be made up of dots having regular
or irregular, uniform or non-uniform shapes, for example, round, square,
hexagonal, elongated, or other dot shapes. Further, the elements of the
pattern may have a shape other than dots, so long as the elements are
indiscernible to the ordinary viewer, cover between 10 and 30 percent,
preferably about 20 or 25 percent of the iris, and leave a substantial portion
of
the iris section within the interstices of the pattern non-opaque. The
patterns
that make up the portions of the iris can be islands of color or worms,
corkscrews, starbursts, spokes, spikes, striations, radial stripes, zig-zags
and
streaks. In certain cases, a single color background is used to complement
the multi-pattern design. These patterns blend with each other to provide a
colored contact fens that enhances the structure of the iris of a person
wearing the lens.
One embodiment of this invention includes a multiple color pattern that
greatly improves the natural appearance of the wearer's iris, even over that
of
one and two color lenses. To produce this embodiment, three (or more)
colored patterns are printed in three or more portions. A first portion of the
elements are a first shade and generally have a greatest concentration of dots
or other elements located generally on the outside of, but within, the iris
section, i.e. at or near the outer perimeter of the annular iris section. This
section may be shaped as the outermost starburst. A preferable first outside
portion pattern or outermost starburst is shown in Figure 2. Black, or some
other dark color such as gray, dark-brown or dark blue, is most often used as
the color of the outermost starburst.
A second portion (the outer starburst) of the elements are a second
shade, which is different from the first shade, and has elements with a
greatest concentration located generally on the inside of the outermost
starburst, and generally, although not always, surrounded by the outermost
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starburst portion. A preferable second portion or outer starburst appears in
Figure 3. The outer starburst can be many colors, for example, blue, gray,
brown, light blue, turquoise, violet, blue-violet, aqua, yellow or green. Most
preferably, the outer starburst is turquoise. When the outer starburst is not
turquoise, the turquoise colorant may be applied in a different pattern.
A third portion (the inner starburst) of the elements are of a third shade,
which is different from the second shade and either the same or different from
the first shade. This third portion has a greatest concentration of elements
located generally, but not always, on the inside of the other two portions.
Generally, the greatest concentration of elements of the third portion is
surrounded by the concentration of elements of the other two portions. A
preferable third inside portion pattern, preferably an inner starburst,
appears
in Figure 4. The preferred color for the inner starburst is hazel, but other
colors to be used include yellow, yellow-green, brown, yellow-brown, gold and
7 5 orange. Figure 1, the preferred embodiment of the present invention, shows
a
combination of Figures 2, 3 and 4.
In the preferred embodiment, a first uneven border differentiates the
outermost starburst and the outer starburst portions of the pattern elements,
however, the elements of the outermost and outer starbursts overlap, mix and
blend together, either in actuality or merely in perception, to create the
desired
effect. A second uneven border differentiates the outer starburst and the
inner starburst portions of the pattern, however, again the elements of the
outer and inner starbursts overlap, mix and blend together, either in
actuality
or in perception. If the patterns of Figures 2, 3 and 4 are merged to form a
three color lens, the uneven edge of the pattern shown in Figure 2 will merge
and overlap with the pattern shown in Figure 3 to form the first uneven border
between the outermost and outer starbursts. Further, the uneven edge of the
pattern shown in Figure 4 will merge and overlap with the pattern shown in
Figure 3 to form the second uneven border between the outer and inner
starbursts.
In certain patterns, the outer starburst may contain a pattern that
extends further toward the periphery of the lens than the pattern of the
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outermost starburst. In other patterns, the outer starburst may contain a
pattern that extends further toward the pupil section of the lens than the
pattern of the inner starburst.
Alternative embodiments of the present invention include minimum and
maximum distances of the uneven borders from the outer perimeter of the iris
section. For example in one alternative embodiment, the minimum distance
of the first uneven border from the outer perimeter of the iris section is
from
about 5% to about 60% of the radial width of the iris section, and the
maximum distance of the uneven border from the outer perimeter of the iris
section is from about 25% to about 95% of the radial width of the iris
section,
and the minimum distance of the second uneven border from the outer
perimeter of the iris section is from about 15% to about 75%~of the radial
width of the iris section, and the maximum distance of the uneven border from
the outer perimeter of the iris section is from about 50% to about 95% of the
radial width of the iris section.
(n another embodiment, the minimum distance of the first uneven
border from the outer perimeter of the iris section is from about 15% to
aboufi
50% of the radial width of the iris section, and the maximum distance of the
uneven border from the outer perimeter of the iris section is from about 45%
to about 95% of the radial width of the iris section, and the minimum distance
of the second uneven border from the outer perimeter of the iris section is
from about 15% to about 65% of the radial width of the iris section, and the
maximum distance of the uneven border from the outer perimeter of the iris
section is from about 60% to about 95% of the radial width of the iris
section.
In another embodiment, the minimum distance of the first uneven
border from the outer perimeter of the iris section is from about 15% to about
50% of the radial width of the iris section, and the maximum distance of the
uneven border from the outer perimeter of the iris section is from about 45%
to about 95% of the radial width of the iris section, and the minimum distance
of the second uneven border from the outer perimeter of the iris section is
from about 15% to about 65% of the radial width of the iris section, and the
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maximum distance of the uneven border from the outer perimeter of the iris
section is from about 60% to about~95% of the radial width of the iris
section.
In yet another alternative embodiment, the outer starburst pattern may
extend to the periphery of the iris section of the contact lens, such that
some
elements that make up the outer starburst are outside of all of the elements
that make up the outermost starburst pattern, and/or the elements that make
up the outer starburst pattern extend closer to the pupil section such that
some of those elements are inside all of the elements of the inner starburst
pattern.
In yet another alternative embodiment, the inner starburst pattern
creates an interdigitation configuration with either the outermost starburst
pattern or the outer starburst pattern or both patterns. Further, the
outermost
starburst pattern may create an interdigitation configuration with the outer
starburst pattern. In an interdigitation configuration, one pattern intersects
another similar to the fingers on one hand placed between the fingers on the
other hand in a planar fashion.
Referring to Figure 5, a graph of reflectance versus wavelength of a
preferred turquoise colorant on a contact lens is shown. The graph shows
that a contact lens having the turquoise colorant on it, when measured
spectrophotometrically, comprises a. non-standard reflectance between about
430 and about 600 nm, in which the reflectance rises to about 30 reflective
units at a wavelength of approximately 4$0 nm. Between 600 nm and 750
nm, the reflectance is about 7 reflective units.
The turquoise colorant that produces the above reflectance data is
preferably an ink paste containing the following ingredients:
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_$_
INK PASTE
COLOR TURQUOISE
Ingredient Weight Target Target
PercentWei ht Wei
ht
Eth I Lactate30.00 180.00 900.00
Binder Soln58.16 348.96 1744.80
PCN Blue 0.63 3.78 18.90
PCN Green 2.25 13.50 67.50
Ti02 8.88 53.28 266.40
Carbazole 0.08 0.48 2.4Q
violet
Total Wt. I -- _ 3000
(g) I 600
~
A contact lens having only the above turquoise colorant thereon has
been measured under the CIE Color Notation System. The contact lens has
the following measurements: a L* of about 43.3, an a* of about -24.9, and a b*
of about -9.8.
The CIE Color Notation System, a way in which to measure color, is a
colorimetric specification system based on stimulus-response characteristics
adopted by the CIE in 1931. The current recommendations for the system
may be obtained from the official publication, CIE Publication No. 15 (E-
1.3.1)
1971, Colorimetry Official Recommendation of the international Commission
on Illumination available from the National Bureau of Standards, Wash., D.C.
20234.
The CIE Standard Observer is the observer data adopted by the CIE to
represent the response of the average human eye, when light-adapted, to an
equal energy spectrum. Unless otherwise specified, the term applies to the
data adopted in 1931 for a 2 degree field of vision. The data adopted in 1964,
sometimes called the 1964 observer, were obtained for a 10 degree, annular
field which excludes the 2 degree field of the 1931 observer functions.
The colorant in the present invention can be measured
spectrophotometrically. In accordance with the CIE method of measurement,
and in particular the CIE 1976 Color Difference Equation:
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_g_
rla
~crc~L*~ a*~ b* _ ~~~ *~z + ~~a ~'~z '~ (fib *~2
r/3
where L* = 25 1 y Y -16 (1 < Y < 100
0
1/3 r/3
a*=S00
Xo Yo
Il3 Il3
b* = 200 Y Z P
Yo Zo
X, Y, and Z are the tristimulus values of the sample, Xo, Yo, and Zo
define the color of the nominally white object color stimulus (the
illuminant);
DL=L* for the sample, -L* for the standard; FAA*~ for the sample, -a* for the
standard; -b=b* for the sample, -b* for the standard.
Two panels containing the colorant of the present invention were
measured spectrophotometrically in accordance with the CIE Color Notation
System, using a standard of olive-gold #1133-67. The olive-gold standard is
52.160 for L*, -3.384 for a*, and 32.585 for b*.L* for panel #1 was measured
to be 52.142, while a* and b* measured -3.365 and 32.564 respectively. 0L
measured at -0.018, ~a* measured at 0.019, Ob* measured at -0.021, and DE
was 0.034. On the panel #2, L* was measured to be 52.018,. while a* and b*
measured -3.265 and 32.592 respectively. DL measured at -0.142, ~a*
measured at 0.118, ~b* measured at 0.006, and DE was 0.185.
In a preferred embodiment, the turpuoise colorant is patterned as an
outer starburst on a contact lens. The contact lens may have another colorant
that is patterned as an inner starbust. Preferably, the inner starburst is
hazel.
More preferably, the hazel colorant is an ink paste having the following
ingredients:
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INK PASTE
COLOR HAZEL
Ingredient Weight Target Target
Percent Wei ht Wei ht
Eth I Lactate30.00 180.00 900.00
Binder Soln63.49 380.94 1904.70
PCN Blue 0.06 0.36 1.80
Ti02 0.61 3.65 18.3
Red 1.54 9.25 46.20
10 Yellow 4.30 25.80 129.00
Total Wt. 651 ~ 3000
(q)
Referring to Figure 6, a graph of reflectance versus wavelength of the
hazel colorant, and no other colorants, on a contact lens is shown. The graph
5 shows that a contact lens having the hazel colorant on it, when measured
spectrophotometrically between 360 nm and 550 nm rises gradually from
about 5 reflective units to about 10 reflective units. From about 550 nm to
about 590 nm, the reflectance rises rapidly to about 21 reflective units.
Between 590 nm and 750 nm, the reflectance is generally higher than 21
10 reflective units and lower than about 25 reflective units.
A contact lens having only the above hazel colorant thereon has been
measured under the CIE Color Notation System. The contact lens has the
following measurements: a L* of about 42.3, an a* of about 15.8, and a b* of
about 18.9.
A preferred contact lens may have still another colorant, preferably
patterned as an outermost starburst. Preferably, the colorant is dark. More
preferably, the colorant is a black ink paste comprising 10 black, such as the
ink paste shown in the following table:
INK PASTE
COLOR BLACK
_ Weight Target Target
Ingredient Percent Wei ht Wei ht
Eth I Lactate23.98 156.11 719.40
Binder Soln64.04 416.90 1921.20
TiOz 11.98 77.99 359.4
Total Wt. 651 3000
Referring to Figure 7, a graph of reflectance versus wavelength of the
black colorant, and no other colorants, on a contact lens is shown. The graph
shows that a contact lens having the black colorant on it, when measured
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spectrophotometrically, comprises a substantially straight line at about 5
reflective units across all measured wavelengths.
A contact lens having only the above black colorant thereon has been
measured under the CIE Color Notation System. The contact lens has the
following measurements: a L* of about 25.5, an a* of about 0.54, and a b* of
about -0.15.
Producing the opaque portions of the iris section of the contact lenses
is preferably accomplished by printing the lens three times using the known
printing process of Knapp's U.S. Pat. No. 4,582,402, incorporated herein by
reference, and the known printing process of Rawlings' U.S. Patent Nos.
5,034,166 and 5,116,112, incorporated herein by reference. Generally, a
plate or cliche having depressions in the desired pattern is smeared with ink
of the desired shade. Excess ink is removed by scraping the surface of the
plate with a doctor blade leaving the depression filled with ink.
A silicon rubber pad is pressed against the plate to pick up the ink from
the depressions and then is pressed against a surface of the lens to transfer
the pattern to the lens. The printed pattern is then cured to render it
unremovable from the lens. Of course, either the anterior or posterior
surfaces of the lens may be printed, but printing the anterior surface is
presently preferred.
The preferred lenses and ink ingredients used to practice this invention
are known and described in Loshaek's U.S. Pat. No. 4,668,240, incorporated
herein by reference. The specific ingredients and target weights are
described in detail below. Very briefly, a lens constructured of polymer
having
-COOH, -OH, or -NH2 groups is printed with ink containing binding polymer
having the same functional groups, opaque coloring substance, and a
diisocyanate compound. First a solution of binding polymer and solvent is
prepared and this solution is mixed with paste containing the coloring
substance to form an ink. The preferred binding polymer solutions have a
viscosity of about 35,000 CPS for blue, gray, brown and black, and 50,000
CPS for green. The opaque ink is printed and cured on the lens surface.
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Ink pastes and pigments which can be used in the present invention
can be made in a number of different ways using the ingredients and
percentages (by weight) as described below in the ink color charts. For
example, a hazel ink paste can be made using 64.59 percent binder solution
(by weight), 30.00 percent ethyl lactate, 0.61 percent titanium dioxide, 0.06
percent PCN blue, 4.30 percent iron oxide yellow, and 1.54 percent iron oxide
red. Although these colors are used for the preferred embodiments, other
colors or variations of the weight percentage of ingredients may be used. The
charts below are merely a representative example of the possible inks and
pigment levels, and is not a complete list. One having ordinary skill in the
art
could develop other inks and pigment levels that would provide an enhancing
effect to the iris of a person wearing the contact lens.
Of course, alternative ways to form colored opaque elements of the
lens may be used. For example, selected portions of the iris section of a
wetted hydrophilic lens may be impregnated with a solution of a first
substance, such as barium chloride. Then the lens may be immersed in a
solution of a second substance, such as sulfuric acid, that forms an opaque,
water-insoluble precipitate with the first substance, for example barium
sulfate. Thus an opaque precipitate forms within the lens in a predetermined
pattern in the iris section.
Next, all or at least part of the iris section is colored with an opaque
colorant in a pattern. If the entire iris is colored with translucent tint,
then the
interstices within the pattern will be translucently colored, but still non-
opaque
and in accordance with the preferred embodiment of the present invention.
Optionally, the pupil section of the lens may be colored by a non-opaque tint,
because such tint is not visible when the lens is against the dark pupil
present
in the eye of the wearer. Other alternative opaquing methods include use of a
laser as described in U.S. Pat. No. 4,744,647 and finely ground particles as
described in U.S. Pat. No. 4,460,523.
The process of the present invention for making colored contact lenses
is as follows. A transparent contact lens comprising at least a pupil section
and an iris section surrounding the pupil section is provided. If the lens is
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constructed of a hydrophilic material, it also has a peripheral section
surrounding the iris section. For hydrophilic material, the steps described
below are performed with the material in an unhydrated state. Preferred
hydrophilic materials are disclosed by Loshaek in U.S. Pat. No. 4,405,773,
incorporated herein by reference.
The colored pattern may be deposited onto the iris section of the lens
in any manner. The currently preferred method is by offset pad printing,
described below in some detail.
A plate as (not shown) is prepared having fiat surface and circular
depressions corresponding to the desired dot pattern. To make the pattern
shown in Figures 2, 3 and 4, each depression should have a diameter of
approximately 0.1 mm, and a depth of approximately 0.013 mm. The
depressions are arranged to cover an annular shape corresponding to that of
the iris section of the lens.
The plate may be made by a technique that is well known for making
integrated analog or digital circuits. First a pattern about 20 times as large
as
the desired pattern is prepared. Next the pattern is reduced using well-known
photographic techniques to a pattern of the exact desired size having the
portion to be colored darker than the remaining area. A flat surface is
covered
by a photo resist material that becomes water insoluble when exposed to
light. The photo resist material is covered with the pattern and exposed to
light. The portion of the photo resist pattern is removed by washing with
water
and the resulting plate is etched to the required depth. Then the remainder of
the photo resist material is mechanically removed.
Colorant, comprising a pigment and binder or carrier for the pigment, is
deposited on the flat surface of the plate and scraped across the pattern with
a doctor blade. This causes depressions to be filled with ink while removing
excess ink from the flat surface: The colorant may be more or less opaque
depending on the degree of color change desired. The opacity may be varied
by modifying the proportion of pigment to binder in the colorant. It will be
recognized that a desired affect may be obtained using a highly opaque
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colorant or by having a somewhat less opaque colorant and covering a
greater~portion of the iris section surface.
A pad made of silicon rubber, impregnated with silicon oil for easy
release, is pressed against the pattern, removing ink from depressions. The
ink on the pad is allowed to dry slightly to improve tackiness, then pressed
against the front surface of the contact lens, depositing the ink in the
desired
pattern over the iris section. Of course the pad must have enough flexibility
to
deform to fit over the convex front surface of the lens. For a more natural
effect, the printing step may be repeated one or more times using different
patterns in different colors, since upon close examination, the iris's of many
persons are found to contain more than one color. The printed pattern need
not be absolutely uniform, allowing for enhancement of the fine structure of
the iris.
Next the deposited pattern is treated to render it resistant to removal
from the lens under exposure to the ocular fluids that the lens will encounter
when placed in the eye. The exact method of preventing removal depends on
the material of construction of the lens and the pattern. Mere air drying or
heating the lens may suffice. For hydrophilic lenses, the techniques for
coating the opaque pattern described in Wichterle, U.S. Pat. No. 3,679,504
(incorporated herein by reference), may be used.
The method for manufacturing a preferred colored contact lens
generally includes the steps of applying three portions of colorant to the
surface of a transparent contact lens and rendering the colorant resistant to
removal from ocular fluids. The printed contact lens will have a non-opaque
pupil section and an iris section surrounding said pupil section with the
three
portions of colorant. The first portion of colorant, or outermost starburst,
is of
a first shade, the second portion of colorant, the outer starburst, is a
second
shade which is different than the first shade, and the third portion of the
colorant, or the inner starburst, is a third shade which is different than the
second shade and may or may not be the same as the first shade.
The outermost starburst will be located such that the greatest
concentration of elements of the outermost starburst are located generally on
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the outside of, but still within, the iris section, and generally on the
outside of
the concentration of elements of the outer starburst, the greatest
concentration of elements of the outer starburst will be located generally on
the outside of the greatest concentration of elements of the inner starburst,
and a first uneven border will differentiate the outermost starburst and the
outer starburst although the outermost starburst and the outer starburst
potions will overlap, a second uneven border will differentiate the outer
starburst and the inner starburst although the outer and inner starbursts will
overlap. Thus, a lens capable of changing the apparent color of the iris of a
person wearing the lens and imparting a very natural turquoise appearance
will be provided.
The steps used to deposit the intermittent pattern on the lens surface
include using a first plate having depressions corresponding to the first
portion
or outermost starburst and filling the depressions with colorant of the first
shade, preferably black. The next step is pressing a first flexible pad
against
the first plate and subsequently pressing the first flexible pad against the
surface of the lens (either side) thereby printing the first portion of the
elements.
The next step involves using a second plate having depressions
corresponding to the second portion or outer starburst and filling in the
depressions with colorant of the second shade which is different from the
first
shade, preferably turquoise. The next step involves pressing the second
flexible pad against a second plate and pressing the second flexible pad
against the surface of the lens (either the same or the opposite surface)
thereby printing the second portion of the elements.
The final step involves using a third plate having depressions
corresponding to the third portion or inner starburst and filling the
depressions
with colorant of the third shade which is different from fihe second shade and
is either the same or different from the first shade, preferably hazel. This
is
carried out by pressing a third flexible pad against the third plate and
pressing
the third flexible pad against said surface of the lens (either side) thereby
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printing the third portion of the elements. The resultant lens, when worn,
makes the iris of the wearer appear to be a striking turquoise color.
Although the steps listed above place an order to the printing of the
portions on the lens, the order of printing is not important to the present
invention and any other order of printing would be covered by the present
invention. Further, the process described above may include the maximum
and minimum distances, creating the uneven borders, previously listed in the
alternative embodiments.
An alternative embodiment for printing the different layers on the iris
section of the contact lens provides for ink-jet printing instead of pad
printing
of each layer. Ink-jet printing is accomplished without the need of pads or
plates and can be administered at a higher resolution than pad printing,
thereby providing for greater detail of each colored layer and a more natural
final pattern on the iris section of the contact lens.
Using ink-jet printing also reduces the number of devices that make
contact either with the contact lens or with other devices. For example, a
silicon pad must make contact with a plate or cliche initially and then with
the
contact lens itself. Contact between the parts tends to wear down the parts,
which will fihen require replacements. During the ink-jet process, the
micro-nozzles do not physically make contact with the contact lens, nor with
any other device. The chance of the micro-nozzle wearing out is thereby
reduced.
Further, the ink-jet printer is electronically controlled such that changing
from one color layer to a different color layer can be done easily, by
computer
control. Thus, once a multiple layer contact lens design is determined and
separated into its multiple colored layers, each layer can be applied to the
colored contact lens using an ink-jet process, thereby creating a colored
contact lens capable of changing the apparent color of the wearer's iris to
turquoise.
It can be seen that certain embodiments of the present invention
provide a contact lens capable of changing or modifying the appearance of
the color of the iris to a striking turquoise color, while allowing
visualization of
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the fine structure thereof and providing a natural appearance. Various
changes may be made in the function and arrangement of parts: equivalent
means may be substituted for those illustrated and described; and certain
features may be used independently from others without departing from the
spirit and scope of the invention as defined in the following claims.
