U.S. patent application number 12/883027 was filed with the patent office on 2011-10-20 for monomers and polymers for optical elements.
This patent application is currently assigned to Ophthonix, Inc.. Invention is credited to Gomaa Abdel-Sadek, Jeffrey Chomyn, Andreas W. Dreher, Jagdish JETHMALANI, Jieming Li, Maher Qaddoura.
Application Number | 20110255156 12/883027 |
Document ID | / |
Family ID | 35997097 |
Filed Date | 2011-10-20 |
United States Patent
Application |
20110255156 |
Kind Code |
A1 |
JETHMALANI; Jagdish ; et
al. |
October 20, 2011 |
MONOMERS AND POLYMERS FOR OPTICAL ELEMENTS
Abstract
An optical element includes a first lens; a cover; and a cured
matrix polymer sandwiched between the first lens and the cover; the
matrix polymer, prior to curing, having a monomer mixture dispersed
therein; the matrix polymer being selected from the group
consisting of polyester, polystyrene, polyacrylate, thiol-cured
epoxy polymer, thiol-cured isocyanate polymer, and mixtures
thereof; and the monomer mixture comprising a thiol monomer and at
least one second monomer selected from the group consisting of ene
monomer and yne monomer.
Inventors: |
JETHMALANI; Jagdish; (San
Diego, CA) ; Dreher; Andreas W.; (Escondido, CA)
; Abdel-Sadek; Gomaa; (San Diego, CA) ; Chomyn;
Jeffrey; (San Diego, CA) ; Li; Jieming;
(Fullerton, CA) ; Qaddoura; Maher; (San Diego,
CA) |
Assignee: |
Ophthonix, Inc.
Vista
CA
|
Family ID: |
35997097 |
Appl. No.: |
12/883027 |
Filed: |
September 15, 2010 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
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11935989 |
Nov 6, 2007 |
7821719 |
|
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12883027 |
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10936030 |
Sep 7, 2004 |
7371804 |
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11935989 |
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Current U.S.
Class: |
359/361 ;
264/1.36 |
Current CPC
Class: |
C08F 290/06 20130101;
C08L 25/18 20130101; C08G 75/12 20130101; C08F 212/36 20130101;
C08F 291/00 20130101; C08L 25/18 20130101; G02B 3/0087 20130101;
C08G 75/045 20130101; C08F 212/34 20130101; C08F 290/14 20130101;
C08F 290/00 20130101; C08F 283/00 20130101; Y10T 428/31855
20150401; G02C 2202/14 20130101; C08L 2666/04 20130101 |
Class at
Publication: |
359/361 ;
264/1.36 |
International
Class: |
F21V 9/06 20060101
F21V009/06; G02B 1/12 20060101 G02B001/12 |
Claims
1. An optical element, comprising: a first lens blank; a cover; a
thiol-cured epoxy matrix polymer sandwiched between the first lens
blank and the cover, wherein the thiol-cured epoxy matrix polymer
is produced by crosslinking an epoxy polymer and a thiol monomer by
utilizing a cross-linking agent, wherein the thiol-cured epoxy
matrix polymer further comprises an ene monomer and thiol monomer;
a low order prescription generated on the back surface of the first
lens blank, wherein the low order prescription is specific to a
patient's eye; and a crosslinked ene-thiol polymer that is produced
by radiation curing the ene monomer and thiol monomer that are
dispersed in the thiol-cured epoxy matrix polymer.
2. The optical element of claim 1 wherein the low order
prescription specific to a patient's eye is determined by using a
wavefront aberrometer.
3. The optical element of claim 1 further comprising one or more
additives selected from the group consisting of a photoinitiator, a
polymerization inhibitor, an antioxidant, a photochromic dye, and
an UV-absorber.
4. The optical element of claim 1 wherein the entire optical
element is exposed to uniform radiation curing.
5. The optical element of claim 1 wherein a small region of the
optical element is exposed to three-dimensionally selective
radiation curing to compensate for high order aberrations specific
to the patient's eye as determined by using a wavefront
aberrometer.
6. The optical element of claim 5 wherein the entire optical
element is exposed to a second uniform radiation curing to fix the
compensated high order aberrations.
7. The optical element of claim 1 wherein the crosslinked
thiol-cured epoxy polymer has a first degree of cure, wherein the
first degree of cure is in the range of about 50% to about 100% and
the crosslinked ene-thiol polymer has a second degree of cure,
wherein the second degree of cure is in the range of 1% to about
100%, wherein the first and second degree of cure are determined by
the difference in refractive index between the uncured and the
cured polymer.
8. The optical element of claim 1 in which the optical element
comprises at least two regions in which the refractive indices are
different from each other.
9. The optical element of claim 1 in which the difference in
refractive indices is between 0.0001 and 0.10.
10. The optical element of claim 1 wherein the refractive index of
the first lens blank and cover is in the range of about 1.5 to
about 1.74.
11. The optical element of claim 1 wherein the refractive index of
the mixture of crosslinked thiol-cured epoxy polymer and ene-thiol
polymer is in the range of about 1.5 to about 1.74.
12. The optical element of claim 1 in which the amine is selected
from the group consisting of polyethyleneimine and tetraalkyl
ammonium halide.
13. A method of making an optical element, the method comprising:
selecting a first lens blank; selecting a second lens blank;
sandwiching a pourable matrix polymer and monomer mixture between
the first lens blank and the cover, wherein the matrix polymer
comprises an epoxy polymer and the monomer mixture comprises a
thiol monomer, a crosslinking agent, and an ene monomer; forming a
gelled mixture of the matrix polymer and the thiol monomer by
utilizing the crosslinking agent to produce a thiol-cured epoxy
polymer; generating the second lens blank to make a cover;
generating patient's eye specific low order prescription in the
first lens blank; and forming a cured film by radiation curing the
ene monomer and thiol monomer to form a crosslinked ene-thiol
polymer that is dispersed in the matrix polymer.
14. The method of claim 13 further comprising one or more additives
selected from the group consisting of a photoinitiator, a
polymerization inhibitor, an antioxidant, a photochromic dye, and
an UV-absorber.
15. The method of claim 13 wherein the patient's eye specific low
order prescription is determined by using a wavefront
aberrometer.
16. The method of claim 13 wherein the radiation curing is uniform
over the entire optical element.
17. The method of claim 13 wherein the radiation curing is
three-dimensionally selective over a small region to compensate for
high order aberrations as determined by using a wavefront
aberrometer of the optical element.
18. The method of claim 17 wherein a second uniform radiation
curing is performed over the entire optical element to fix the
compensated high order aberrations.
19. The method of claim 13 wherein the difference in refractive
indices is between 0.0001 and 0.10.
20. The method of claim 13 wherein the amine is selected from the
group consisting of polyethyleneimine and tetraalkyl ammonium
halide.
Description
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application is continuation of U.S. application Ser.
No. 11/935,989, filed Nov. 6, 2007, which is a continuation of U.S.
application Ser. No. 10/936,030, filed Sep. 7, 2004, and entitled
Monomers and Polymers for Optical Elements, the entireties of which
are incorporated herein by reference.
BACKGROUND OF THE INVENTION
[0002] 1. Field of the Invention
[0003] This invention relates to monomeric and polymeric materials,
and to stabilized mixtures of monomeric and polymeric materials
useful for making optical elements such as lenses.
[0004] 2. Description of the Related Art
[0005] Optical elements such as eyeglass lenses are typically made
by casting, grinding and/or polishing lens blanks made from glass
or plastics such as polycarbonate, Finalite.TM. (Sola), MR-8
polymer (Mitsui), and diethylene glycol bis(allylcarbonate) polymer
(CR-39) (PPG Industries). However, lenses made using these
materials and fabrication techniques are only capable of correcting
relatively simple optical distortions. Other fabrication techniques
and polymer compositions have been developed to produce lenses that
correct more complicated optical distortions. However, the
commercialization of such lenses has been complicated by the
relatively small number of suitable polymer compositions currently
available. Polymer compositions such as those described in U.S.
Pat. Nos. 5,236,970; 5,807,906; 6,391,983; and 6,450,642 are not
entirely satisfactory. Hence, there is a need for polymer
compositions suitable for the fabrication of optical elements, and
particularly for optical elements capable of correcting complicated
optical distortions.
SUMMARY OF THE INVENTION
[0006] A preferred embodiment provides a composition comprising: a
matrix polymer having a monomer mixture dispersed therein, the
matrix polymer being selected from the group consisting of
polyester, polystyrene, polyacrylate, thiol-cured epoxy polymer,
thiol-cured isocyanate polymer, and mixtures thereof; the monomer
mixture comprising a thiol monomer and at least one second monomer
selected from the group consisting of ene monomer and yne monomer.
Another preferred embodiment provides a method for making such a
composition comprising intermixing, in any order, the matrix
polymer, the thiol monomer and the second monomer.
[0007] Another preferred embodiment provides a composition
comprising a mixture that comprises a first polymer and a second
polymer, the first polymer being selected from the group consisting
of polyester, polystyrene, polyacrylate, thiol-cured epoxy polymer,
thiol-cured isocyanate polymer, and mixtures thereof; the second
polymer being selected from the group consisting of thiol-ene
polymer and thiol-yne polymer; the mixture comprising at least one
region in which the first polymer has a first degree of cure and
the second polymer has a second degree of cure that may be
different from the first degree of cure. Another preferred
embodiment provides a method for making such a composition,
comprising: providing a composition, the composition comprising a
matrix polymer having a monomer mixture dispersed therein; the
matrix polymer being selected from the group consisting of
polyester, polystyrene, polyacrylate, thiol-cured epoxy polymer,
thiol-cured isocyanate polymer, and mixtures thereof; the monomer
mixture comprising a thiol monomer and a second monomer selected
from the group consisting of ene monomer, yne monomer, and mixtures
thereof; and polymerizing at least a portion of the monomer mixture
to form the second polymer. Preferably, the polymerizing of the
monomer mixture comprises irradiating the composition at ambient or
elevated temperature.
[0008] Another preferred embodiment provides a compound of the
formula
##STR00001##
[0009] in which n is an integer in the range of about 1 to about
6.
[0010] Another preferred embodiment provides a kit comprising: a
first container comprising a thiol monomer; and a second container
comprising a matrix polymer selected from the group consisting of
polyester, polystyrene, polyacrylate, epoxy polymer, isocyanate
polymer, and mixtures thereof; and a second monomer selected from
the group consisting of ene monomer and yne monomer.
[0011] Another preferred embodiment provides an optical element,
comprising: a first lens; a cover; and a matrix polymer sandwiched
between the first lens and the cover; the matrix polymer having a
monomer mixture dispersed therein; the matrix polymer being
selected from the group consisting of polyester, polystyrene,
polyacrylate, thiol-cured epoxy polymer, thiol cured isocyanate
polymer, and mixtures thereof; and the monomer mixture comprising a
thiol monomer and at least one second monomer selected from the
group consisting of ene monomer and yne monomer. Preferably, the
cover is a lens, plano or coating. More preferably, the first lens
is a lens blank.
[0012] Another embodiment provides an optical element, comprising:
a first lens; a cover; and a polymer mixture sandwiched between the
first lens and the cover, the polymer mixture comprising a first
polymer and a second polymer; the first polymer being selected from
the group consisting of polyester, polystyrene, polyacrylate,
thiol-cured epoxy polymer, thiol-cured isocyanate polymer, and
mixtures thereof; the second polymer being selected from the group
consisting of thiol-ene polymer and thiol-yne polymer; the polymer
mixture comprising at least one region in which the first polymer
has a first degree of cure and the second polymer has a second
degree of cure that is different from the first degree of cure.
Preferably, the cover is a second lens, plano or coating. More
preferably, the first lens is a lens blank.
[0013] A polymerizable composition comprising:
[0014] a first ene monomer and a first thiol monomer together
having a first refractive index; and
[0015] a second ene monomer and a second thiol monomer together
having a second refractive index;
[0016] wherein the first ene monomer is selected from the group
consisting of styrene, divinylbenzene,
##STR00002##
[0017] wherein the first thiol monomer is selected from the group
consisting of thiobisbenezenethiol,
##STR00003##
[0018] Another embodiment provides a kit comprising: a first
container comprising a first monomer composition having a first
refractive index, the first monomer composition comprising a first
ene monomer and a first thiol monomer; and a second container
comprising a second monomer composition having a second refractive
index, the second monomer composition comprising a second ene
monomer and a second thiol monomer; wherein the difference between
the first refractive index and the second refractive index is in
the range of about 0.001 to about 0.5.
[0019] Another embodiment is a method of stabilization of
refractive index in the optical element in which the matrix polymer
comprises an amount of a polymerization inhibitor that is effective
to at least partially inhibit polymerization of the monomer
mixture.
[0020] These and other embodiments are described in greater detail
below.
BRIEF DESCRIPTION OF THE DRAWINGS
[0021] These and other aspects of the invention will be readily
apparent from the following description and from the appended
drawings (not to scale), which are meant to illustrate and not to
limit the invention, and wherein:
[0022] FIG. 1 is a cross-sectional view schematically illustrating
a preferred process for making a polymer composition.
[0023] FIGS. 2 and 3 are cross-sectional views schematically
illustrating a preferred lens assembly process.
[0024] FIG. 4 is a reproduction of a photograph of a photomask
suitable for writing a trefoil pattern in an optical element.
[0025] FIG. 5 shows an optical path difference (OPD) map obtained
on an optical element.
[0026] FIG. 6 shows a plot illustrating the change in the OPD
pattern as a function of time for a trefoil written into a sandwich
polymer gel.
[0027] FIG. 7 shows curing curves (dynamic range vs. time) for two
lenses prepared as described in Example 29.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0028] The term "polymer" is used herein in its usual sense and
includes, e.g., relatively large molecules built up by linking
together smaller molecules, natural and synthetic polymers,
pre-polymers, oligomers, crosslinked polymers, blends,
interpenetrating polymer networks, homopolymers, and copolymers
(including without limitation block and graft copolymers).
Likewise, the term "polymerization" is used herein in its usual
sense and includes, e.g., a process of linking together smaller
molecules to form polymers, crosslinking, oligomerization, and
copolymerization. Polymerization includes photopolymerization
(polymerization induced by irradiation) and thermal
photopolymerization (polymerization induced by heat and
irradiation).
[0029] The term "monomer" is used herein in its usual sense and
includes, e.g., molecules that contain one or more polymerizable
groups, including macromers. Monomers that contain more than one
polymerizable group may be referred to herein as "multifunctional."
A multifunctional monomer may be a crosslinker as described below.
The terms "recurring unit" and "repeating unit" are used herein in
their usual sense and include, e.g., the structures within the
polymer that correspond to the linked-together monomers. The term
"matrix polymer" refers herein to a polymer that is capable of
functioning as a matrix, e.g., capable of including within its
interstitial spaces various molecules such as, e.g., polymers and
monomers. A matrix polymer may be crosslinked or non-crosslinked. A
matrix polymer may possess free reactive groups such as acrylate,
vinyl, allyl, methacrylate, epoxy, thiol, hydroxy, etc.
[0030] A "polyester" or "ester polymer" is a polymer that contains
multiple ester recurring units and thus includes unsaturated
polyesters. A "polystyrene" or "styrene polymer" is a polymer that
contains multiple substituted and/or unsubstituted styrene
recurring units and thus includes functionalized styrene polymers
such as poly(allyloxystyrene). A "polyacrylate" or "acrylate
polymer" is a polymer that contains multiple
--(CH.sub.2--C(R.sup.1)(CO.sub.2R.sup.2))-- units, where R.sup.1
represents hydrogen or C.sub.1-C.sub.6 alkyl, and R.sup.2
represents hydrogen, C.sub.6-C.sub.12 aryl, C.sub.6-C.sub.12
halogenated aryl, C.sub.1-C.sub.6 alkyl or C.sub.1-C.sub.6
hydroxyalkyl. An epoxy polymer is a polymer that contains one or
more epoxy groups. A "thiol-cured epoxy polymer" is a polymer
formed by reacting a thiol-containing compound with an epoxy
polymer. An isocyanate polymer is a polymer that contains one or
more isocyanate groups. A "thiol-cured isocyanate polymer" is a
polymer formed by reacting a thiol-containing compound with an
isocyanate polymer. A "polyethyleneimine" is a polymer that
contains ethylene recurring units and imine groups. An
"unsaturated" polymer is a polymer containing one or more
carbon-carbon double bonds.
[0031] An "ene" or "ene monomer" is a monomer that contains one or
more carbon-carbon double bonds. A "thiol" or "thiol monomer" is a
monomer that contains one or more sulfur-hydrogen bonds. A
"thiol-ene polymer" is a polymer formed by the polymerization of an
ene monomer and a thiol monomer. An "yne" or "yne monomer" is a
monomer that contains one or more carbon-carbon triple bonds. A
"thiol-yne polymer" is a polymer formed by the reaction of an yne
monomer and a thiol monomer. A "crosslinking agent" is a compound
that is capable of causing two monomers to be linked to one
another, or a polymer molecule to be linked to another monomer or
polymer molecule, typically by forming a crosslink. Crosslinking
agents may be "crosslinkers", e.g., multifunctional compounds that
become incorporated into the resulting crosslinked polymer, or may
be "curing agents," e.g., catalysts or initiators that bring about
reactions between the monomers, between the polymer molecules,
between polymer molecules and crosslinkers, and/or between polymers
and monomers to form the crosslinks. Curing agents typically do not
become incorporated into the resulting crosslinked polymer. Thus, a
crosslinking agent may be a crosslinker, a curing agent, or a
mixture thereof. A crosslinked polymer may be optionally
crosslinked to such an extent that it becomes infusible and/or
insoluble. The terms "degree of crosslinking" and "degree of cure"
refer to the extent of polymerization or crosslinking of a
particular polymer, and can be expressed as a percentage of the
difference in refractive index between the uncured (monomer) and
fully cured versions of that polymer.
[0032] The term "mixture" is used herein in its usual sense to
include various combinations of components, and thus includes
polymer blends and interpenetrating networks (including
semi-interpenetrating networks). A "blend" of polymers or "polymer
blend" is an intimate mixture of two or more different polymers,
e.g., a mixture of polymers that is phase separated on a
microscopic scale. A "compatible blend" of polymers is a polymer
blend that does not exhibit phase separation on a microscopic scale
using visible light. An "interpenetrating polymer network" (IPN) is
an intimate mixture of two or more polymers in which the polymers
interpenetrate each other and entangle to some degree. An IPN is
typically made by forming and/or crosslinking one polymer in the
presence of monomers and/or another polymer.
[0033] The term "film" is used herein to refer to a material in a
form having a thickness that is less than its height or width. A
film typically has a thickness of about ten millimeters or less. A
film may be free standing and/or may be hard-coated to enhance its
mechanical stability, coated onto a surface or sandwiched between
other materials. For example, a film may be formed while sandwiched
between a substrate and a cover, or placed between a substrate and
cover after being formed. The substrate and/or cover may be
relatively non-stick materials such as polyethylene or fluorinated
polymers that facilitate subsequent removal, or the substrate
and/or cover may be materials (e.g., lens or lens blank) that are
incorporated into the final product, e.g., an optical element. A
composition is considered "substantially transparent to optical
radiation" if it is suitable for use in an optical element such as
a lens, mirror or prism. Thus, such a composition may be colored or
tinted to a degree, e.g., in the general manner of sunglasses or
tinted contact lenses, and still be considered "substantially
transparent to optical radiation."
[0034] The foregoing definitions and examples mentioned therein are
non-limiting and not mutually exclusive. Thus, for example, a
compatible polymer blend may be an IPN and vice versa.
[0035] A preferred embodiment is a composition that comprises a
matrix polymer and a monomer mixture dispersed therein. The matrix
polymer is preferably selected from the group consisting of
polyester, polystyrene, polyacrylate, thiol-cured epoxy polymer,
thiol-cured isocyanate polymer, and mixtures thereof. The matrix
polymer may be obtained commercially or made by methods known to
those skilled in the art. Preferred matrix polymers contain (or are
prepared from polymers that contain) reactive groups (e.g., double
bonds and/or epoxy groups) that facilitate crosslinking.
Preferably, the matrix polymer is unsaturated (e.g., contains
double bonds) and/or contains epoxy groups and/or contains
isocyanate groups. Crosslinking may be accomplished chemically
(e.g., by reacting the matrix polymer with a crosslinker such as a
thiol, preferably in the presence of a curing agent such as an
amine, tin compound, phosphate compound, or mixtures thereof) or
photochemically (e.g., by exposure to visible or ultraviolet
radiation), optionally with heating. The amount of crosslinking
agent used to crosslink the polymer is preferably selected based on
the desired degree of cure and respective curing characteristics of
the matrix polymer and crosslinking agent in a manner generally
well known to those skilled in the art.
[0036] In a preferred embodiment, the matrix polymer is the product
of a chemical reaction between a crosslinking agent and an
unsaturated polyester, unsaturated polystyrene, unsaturated
polyacrylate, or mixture thereof. An example of a preferred
unsaturated polyester is represented by the formula (I) in which n
is an integer in the range of from about 2 to about 5,000,
preferably from about 2 to about 100.
##STR00004##
[0037] Unsaturated polyesters encompassed by the formula (I) are
available commercially (e.g., ATLAC 382-E from Reichhold) or may be
prepared by methods known to those skilled in the art (e.g., from
bisphenol A and maleic anhydride). The unsaturated polyester of the
formula (I) is preferably crosslinked by intermixing with a thiol,
more preferably in the presence of an amine, optionally with
heating. This invention is not bound by theory, but it is believed
that the thiol undergoes Michael addition with the fumaric acid
recurring unit to bring about crosslinking of the unsaturated
polyester. Examples of preferred amines useful for crosslinking
unsaturated polymers include polyethyleneimine and tetraalkyl
ammonium halide. See Anthony Jacobine, "Radiation Curing Polymer
Science and Technology," Vol. 3, Ed. by J. P. Fouassier and J. F.
Rabek, Elsevier Applied Science, pp. 219-268.
[0038] An example of a preferred unsaturated polystyrene is a
poly(allyloxystyrene), preferably as represented by the formula
(II) in which n is an integer in the range of from about 2 to about
5,000, preferably from about 2 to about 100.
##STR00005##
[0039] The unsaturated polystyrene of the formula (II) is available
commercially or may be prepared by methods known to those skilled
in the art. Unsaturated polystyrenes are preferably crosslinked by
exposure to visible or ultraviolet radiation, optionally with
heating. This invention is not bound by theory, but it is believed
that the unsaturated groups (e.g., allyloxy groups) in the presence
of a suitable curing agent (e.g., an initiator) react with one
another or with thiols to bring about crosslinking of the
unsaturated polystyrene.
[0040] In a preferred embodiment, the matrix polymer is an epoxy
polymer, an isocyanate polymer, or a mixture thereof, more
preferably a thiol-cured epoxy polymer, thiol-cured isocyanate
polymer, or mixture thereof. An example of a preferred epoxy
polymer is represented by the formula (III) in which n is an
integer in the range of from about 2 to about 5,000, preferably
from about 2 to about 100.
##STR00006##
[0041] The epoxy polymer of the formula (III) is available
commercially or may be prepared by methods known to those skilled
in the art. A wide variety of epoxy polymers may be prepared by the
reaction of epoxy monomers with comonomers (e.g., amines, alcohols,
carboxylic acids and/or thiols) in a manner generally known to
those skilled in the art. Examples of preferred epoxy monomers and
polymers include those represented by the following structures in
which n is an integer in the range of from about 2 to about 5000,
preferably from about 2 to about 100:
##STR00007##
[0042] Epoxy polymers are preferably crosslinked by intermixing
with a thiol monomer (crosslinker) and an amine curing agent,
optionally with heating. Thiol-cured epoxy polymers are
preferred.
[0043] An example of a preferred isocyanate polymer is represented
by the formula (IV), wherein each X is individually selected from
the group consisting of O, NH and S; wherein R.sub.1 and R.sub.2
are each individually selected from the group consisting of
C.sub.2-C.sub.18 aliphatic and C.sub.6-C.sub.18 aromatic; and
wherein m is an integer in the range of from about 1 to about
5,000, preferably from about 1 to about 100.
##STR00008##
[0044] The isocyanate polymer of the formula (IV) is available
commercially or may be prepared by methods known to those skilled
in the art. Examples of preferred commercially available isocyanate
polymers include Desmodur 3300AR3600 (homopolymer of hexamethylene
diisocyanate, CAS 28182-81-2, available from Bayer). A wide variety
of isocyanate polymers may be prepared by the reaction of
isocyanate monomers with comonomers (e.g., alcohols, amines and/or
thiols) in a manner generally known to those skilled in the art.
Examples of preferred commercially available isocyanate monomers
(Mondur, from Bayer) include those represented by the following
structures:
##STR00009##
[0045] Isocyanate polymers are preferably crosslinked by
intermixing with a crosslinking agent (e.g., thiol, amine, alcohol,
tin compound, and/or phosphate compound), optionally with heating.
Thiol-cured isocyanate polymers are preferred. Preferably, the
thiol crosslinker is a thiol monomer as described elsewhere
herein.
[0046] The monomer mixture dispersed within the matrix polymer
preferably comprises monomers that undergo step-growth
polymerization, more preferably comprises monomers that undergo
radiation-initiated step growth polymerization. For example, a
preferred monomer mixture comprises a thiol monomer and at least
one second monomer. The second monomer is preferably an ene
monomer, an yne monomer, or a mixture thereof, more preferably a
multifunctional ene monomer. The thiol monomer is preferably a
multifunctional thiol monomer. Non-limiting examples of preferred
thiol monomers include those represented by the following
structures:
##STR00010##
[0047] The structures of additional examples of preferred thiol
monomers are shown in Table 1, in which n, m, x, y, and z are each
individually in the range of about 2 to about 5,000, preferably 2
to 100. A wide variety of thiol monomers may be purchased
commercially or prepared by methods known to those skilled in the
art.
[0048] The second monomer is preferably an ene monomer, an yne
monomer, or a mixture thereof. The second monomer is preferably a
multifunctional monomer. Non-limiting examples of preferred ene
monomers include those represented by the following structures:
##STR00011##
[0049] The structures of additional examples of preferred second
monomers are shown in Table 2, in which n, m, x, y, and z are each
individually in the range of about 2 to about 5000, preferably from
about 2 to about 100. A particularly preferred type of ene monomer
is represented by structure (V), in which n is an integer,
preferably in the range of about 1 to about 6. A preferred method
for preparing the ene monomer represented by the structure (V) in
which n=1 is described in the Examples below.
##STR00012##
[0050] Polymer compositions that comprise a matrix polymer and a
monomer mixture dispersed therein preferably further comprise a
curing agent (preferably a photoinitiator) and optionally one or
more additives such as a polymerization inhibitor, antioxidant,
photochromic dye, and/or UV-absorber. Such additives are
commercially available. Photoinitiators may be present in the
polymer composition as the residue of a prior photoinitiated
polymerization (e.g., for the preparation of the matrix polymer) or
may be included for other purposes, preferably for initiating
polymerization of the monomer mixture. The amount and type of
photoinitiator are preferably selected to produce the desired
polymer, using selection criteria generally known to those skilled
in the art. The compound 1-hydroxy-cyclohexyl-phenyl-ketone
(available commercially from Ciba under the trade name Irgacure.TM.
184) is an example of a preferred photoinitiator. Other preferred
photoinitiators include benzoin, Irgacure.TM. 500 (50%
1-hydroxy-cyclohexyl-phenyl-ketone+50% benzophenone), Irgacure.TM.
651 (2,2-dimethoxy-1,2-diphenylethan-1-one), Irgacure.TM. 819
(bis(2,4,6-trimethylbenzoyl)-phenylphosphineoxide), and
Irgacure.TM. 2959
(1-[4-(2-hydroxyethoxy)-phenyl]-2-hydroxy-2-methyl-1-propane-1-one).
Examples of preferred polymerization inhibitors include N-PAL
(N-nitroso N-phenylhydroxylamine aluminium salt) and MEHQ
(4-methoxyphenol). Examples of preferred UV-absorbers include
Tinuvin.RTM. 327
(2,4-di-tert-butyl-6-(5-chlorobenzotriazol-2-yl)phenol), and
Tinuvin.RTM. 144
(bis(1,2,2,6,6-pentamethyl-4-piperidinyl)(3,5-di-(tert)-butyl-4-hydro-
xybenzyl)butylpropanedioate). Examples of preferred antioxidants
include TTIC (tris(3,5-di-tert-butyl-4-hydroxybenzyl)isocyanurate),
and IRGANOX 1010
(tetrakis-(methylene-(3,5-di-terbutyl-4-hydrocinnamate)methane).
Examples of photochromic dyes include spiro-naphthoxazines and
naphthopyrans (e.g., Reversacol.TM. dyes from James Robinson, UK)
and those disclosed in PCT WO 02091030, which is hereby
incorporated by reference and particularly for the purpose of
describing photochromic dyes.
[0051] Polymer compositions that comprise a matrix polymer and a
monomer mixture dispersed therein may be prepared by intermixing,
in any order, the matrix polymer, the thiol monomer and the second
monomer. Preferably, intermixing is conducted by forming and/or
crosslinking the matrix polymer in the presence of the thiol
monomer and second monomer. For example, in a preferred embodiment,
an unsaturated polyester matrix polymer is intermixed with a
photoinitiator, a thiol monomer, an ene monomer, and optionally a
crosslinking agent (e.g., an amine) to form a composition
comprising an unsaturated polyester matrix polymer and a monomer
mixture (thiol and ene) dispersed therein. In another embodiment,
that composition is heated and/or irradiated to at least partially
crosslink the unsaturated polyester, thereby forming a composition
comprising a thiol-cured polyester, a remaining thiol monomer and
the ene monomer. Preferably, the amount of remaining thiol monomer
is sufficient to react with the ene monomer. It will be understood
by those skilled in the art that a portion of the ene monomer may
also react with pendant thiol groups tethered on unsaturated
polyester and become part of the thiol-cured polyester. In an
additional embodiment, discussed below, either of these
compositions (each comprising a matrix polymer and a monomer
mixture dispersed therein) is irradiated to at least partially
polymerize the thiol and ene monomers to form a thiol-ene polymer,
thereby forming a mixture comprised of the matrix polymer (e.g.,
polyester) and the thiol-ene polymer. The relative amounts of ene
and thiol monomers in the polymerizable composition are preferably
such that the number of ene functional groups is about equal to the
number of thiol functional groups.
[0052] FIG. 1 schematically illustrates a preferred process for
making a polymer composition that comprises a matrix polymer and a
monomer mixture dispersed therein. In the illustrated embodiment,
the matrix polymer is a polyester and the monomer mixture comprises
a thiol monomer and an ene monomer. It will be understood that
other matrix polymers and monomers may be used in the process
described herein in connection with FIG. 1, including those
described herein. In addition, variations of the preferred process
may be practiced, using the knowledge of one skilled in the art in
light of the teachings provided herein.
[0053] The composition 310 illustrated in FIG. 1 contains 13 parts
of an unsaturated polyester represented by the formula (I), 10
parts of an ene monomer (pentaerythritol triallyl ether), 21 parts
of a thiol monomer (trimethylolpropane tri(3-mercaptoproprionate)),
1.1 parts of an amine (polyethyleneimine), and 0.075 parts of a
photoinitiator Irgacure.TM. 184 (all parts herein are by weight,
unless otherwise stated). The composition 310 is degassed under
vacuum and sandwiched between a glass cover 315 and a glass
substrate 320, then crosslinked by heating 325 for about 40 minutes
at a temperature of about 65.degree. C. to 75.degree. C. Longer or
shorter periods of heating may be employed for crosslinking other
polymers. The heating 325 results in the crosslinking of the
unsaturated polyester with the thiol in the composition 310,
thereby forming a composition 330 that contains a thiol-cured
polyester having free thiol groups, the ene monomer, the remaining
thiol monomer, the photoinitiator, and (typically) a small amount
of residual amine (e.g., amine not consumed by crosslinking). It is
understood that small amounts of the ene monomer, thiol monomer,
and/or photoinitiator may be consumed (e.g., incorporated into the
crosslinked polyester in the composition 330) during the
crosslinking.
[0054] The glass cover 315 and substrate 320 allow the composition
330 to be prepared in the form of a uniform film having a
controlled thickness. For example, spacers may be optionally placed
between the plates to form a film having a desired thickness. One
or both of the cover 315 and substrate 320 may be flat or curved
plates that may be used to form a film having a desired topology.
Preferably, the covers are substantially transparent to optical
radiation. Examples of suitable cover and substrate materials
include optically transparent materials having a refractive index
in the range of about 1.5 to about 1.74, such as glass and plastic,
preferably polycarbonate, Finalite.TM. (Sola), MR-8 polymer
(Mitsui), and diethylene glycol bis(allylcarbonate) polymer (CR-39)
(PPG Industries). The cover may be a protective coating.
Preferably, one or both of the covers is a lens, plano lens, or
lens blank.
[0055] It is also understood that the glass cover 315 and substrate
320 are optional. For example, the composition 310 may be cast onto
a substrate and crosslinked to form a free-standing film, e.g., a
film having sufficient mechanical strength to allow it to be peeled
from the substrate, without using a cover. Preferably, the physical
form of the composition 330 is a gel, e.g., a gel in film form. To
facilitate peeling the filmy gel from the surface, it is preferable
to treat the surface of the substrate with a release agent prior to
applying the composition 310, and/or to use a hard coated UV-clear
CR-39 substrate. The peeled film may be hard coated to enhance its
mechanical stability.
[0056] Polymer compositions that comprise a matrix polymer and a
monomer mixture dispersed therein may be used to make compositions
that comprise a first polymer and a second polymer, the second
polymer being formed by polymerization of the monomer mixture. For
example, as illustrated in FIG. 1, the composition 330, sandwiched
between the glass cover 315 and substrate 320, is exposed to
radiation 340 (preferably with heating), thereby activating the
photoinitiator and polymerizing 345 the monomers dispersed within
the composition 330 to form a thiol-ene polymer in the presence of
the crosslinked polyester. A photomask 347 is used to control the
amount of radiation received at different points in the composition
330. The photomask 347 may comprise regions 342 that are
essentially opaque to the radiation, regions 343 that are
essentially transparent to the radiation, and regions such as the
region 344 that transmit a portion of the radiation. The resulting
composition 350 thus contains the crosslinked polyester, the
thiol-ene polymer (e.g., in regions 352, 353 exposed to the
radiation 340), the partially polymerized thiol-ene (e.g., in
region 352, exposed to the radiation 340) and (in some cases)
largely un-polymerized thiol monomer and ene monomer (e.g., in
regions 351 not exposed to radiation 340).
[0057] It will be understood that the degree of cure of the
thiol-ene polymer in any particular region will be related to the
amount of radiation transmitted by the photomask 347 to that
particular region. Thus, the degree of cure of the thiol-ene
polymer may be controlled by the photomask, allowing various
patterns of cure to be written into the composition 350. For
example, in the embodiment illustrated in FIG. 1, the cure pattern
in the composition 350 results from the varying degrees of cure in
the regions 351, 352, 353. Additional regions of the photomask with
additional variations in their transmissibility may be used. It
will be understood that a relatively simple cure pattern is shown
in FIG. 1 for the purposes of illustration, and that much more
complex cure patterns may be obtained. For example, a complex
pattern may be created in a photomask using well known
photolithographic techniques, and that photomask may be used to
create a correspondingly complex cure pattern in the polymer
composition. Other digital mask systems such as Digital Light
Projector (DLP) along with a UV-light source or UV-Vertical Cavity
Surface Emitting Laser (UV-VSCEL) or laser (e.g., triple YAG) or
bundled UV-LED may be used.
[0058] Preferably, composition 350 is a polymer blend, more
preferably an IPN or compatible blend. The polymerization of the
monomers in the composition 330 may be in one or multiple stages,
e.g., by exposure to a single dose of radiation or multiple doses.
Likewise, the monomers in the various regions 351, 352, 353 of the
composition 350 may be polymerized to the same degree or different
degrees, and/or at the same or different times. Thus, for example,
the photomask 347 may be used as illustrated in FIG. 1 to
simultaneously irradiate various regions of the composition 330 to
produce a composition in which the thiol-ene polymer is polymerized
to varying degrees in the various regions 351, 352, 353. The same
or similar effect may be achieved by sequentially irradiating
various regions, e.g., by varying the intensity of a scanning light
source (e.g., a laser) across the composition 330. Additional
monomer(s) may be added at any stage of the process. For example,
monomer(s) may be diffused into the composition 330 and/or the
composition 350, then later polymerized, as illustrated in Example
16 below.
[0059] The crosslinking of the matrix polymer and the
polymerization of the monomers may be conducted simultaneously or
sequentially (in either order), preferably sequentially, and the
degree of polymerization or crosslinking of each polymer may be
controlled independently, so as to be different (or the same) from
place to place within the composition. Preferably, the matrix
polymer is crosslinked prior to polymerization of the monomers. For
example, the composition 350 illustrated in FIG. 1 contains a
crosslinked polyester in which the degree of crosslinking is
substantially constant throughout the composition, and a thiol-ene
polymer having degrees of polymerization in the various regions
351, 352, 353 that are different from each other.
[0060] In many end-use applications, e.g., lenses, it may be
undesirable for the composition 350 to contain slightly polymerized
or un-polymerized materials. In a preferred embodiment, the
monomers in a substantial portion of the regions are at least
partially polymerized, thereby advantageously reducing the residual
monomer content and increasing the stability of the composition.
For example, in FIG. 1 the entire composition 350 is exposed to
radiation 355, thereby at least partially polymerizing the thiol
and ene monomers 360 throughout the composition 350 to produce the
polymer composition 365. Preferably, the degree of cure
(polymerization) of the thiol and ene monomers is controlled so
that the cure pattern previously written into the composition 350
is largely preserved. Such control may be exercised by, e.g.,
exposing the composition 350 to radiation in a manner that
increases the degree of cure of the entire composition 350 by
approximately the same amount. For example, if a region 352 of the
composition 350 has been previously cured to a degree of cure of
about 60% and another region 353 has been cured to a degree of cure
of about 20%, the difference in degree of cure between the two
regions 352, 353 is about 40%. This difference in degree of cure
may be largely preserved (and thus the difference in physical
properties, e.g., refractive index, may be largely preserved) by
exposing both regions 352, 353 to an amount of radiation that
increases the degree of cure to 70% and 30% in the resulting two
regions 362, 363, respectively.
[0061] For compositions comprising a mixture that contains a first
polymer and a second polymer (e.g., the compositions 350, 365), the
relative amounts of first and second polymer are preferably in the
range of about 0.01:9.99 to about 9.99:0.01, more preferably about
3:7 to about 7:3, by weight. The relative amounts of first and
second polymer may be controlled by making the precursor
composition (e.g., the composition 330) with the corresponding
amounts of matrix polymer and monomers, and/or adding additional
monomers and/or polymers during the process of making the desired
composition.
[0062] Those skilled in the art, in light of the teachings provided
herein, will understand that the physical properties of the first
and second polymers may each be independently controlled, both
temporally and spatially. Thus, for example, a preferred embodiment
provides a composition comprising a mixture that comprises a first
polymer and a second polymer, in which the mixture comprises at
least one region in which the first polymer has a first degree of
cure and the second polymer has a second degree of cure that is
different from the first degree of cure. For example, in FIG. 1,
the degree of cure of the first polymer (crosslinked polyester
matrix) in the region 353 of the composition 350 may be the same as
the degree of cure of the second polymer(thiol-ene polymer) in that
region, but preferably the degrees of cure are different. In
addition, the composition preferably comprises a second region in
which the two degrees of cure are also different, both from each
other and, optionally, from the degrees of cure in the first
region. For example, in the composition 350, the degree of cure of
the thiol-ene polymer in the region 353 is different than the
degree of cure of the crosslinked polyester matrix in the region
353, and different from the degree of cure of the thiol-ene polymer
in the region 352. In a preferred embodiment, the first degree of
cure is in the range of about 50% to about 100%, and/or the second
degree of cure is in the range of about 1% to about 100%, based on
the difference in refractive index between the uncured and cured
first polymer as described below. More preferably, the first
polymer is selected from the group consisting of polyester,
polystyrene, polyacrylate, thiol-cured epoxy polymer, thiol-cured
isocyanate polymer, and mixtures thereof, and/or the second polymer
is selected from the group consisting of thiol-ene polymer and
thiol-yne polymer.
[0063] Preferably, the differences in degree of cure in various
regions of the composition result in differences in optical
properties. Thus, measurement of an optical property often provides
a convenient way to express the degree of cure. Refractive index
measurements have been found to be particularly convenient for this
purpose, because the refractive index of a monomer or monomer
mixture is generally different from the corresponding polymer
formed from that monomer or monomer mixture. Therefore, the degree
of cure can be expressed in percentage terms, based on the
difference in refractive index between the uncured and cured
polymer. For example, a hypothetical monomer has a refractive index
of 1.5 and the polymer formed from that monomer has a refractive
index of 1.6. The degree of cure of a partially polymerized
composition formed from that monomer would be considered 10% for a
refractive index of 1.51, 40% for a refractive index of 1.54, 80%
for a refractive index of 1.58, etc. Another method to determine
the degree of cure is to measure the optical path difference (OPD)
by Zygo Interferometry.
[0064] Compositions described herein (comprising a first matrix
polymer and a monomer mixture or comprising a first polymer and a
second polymer) preferably have a refractive index in the range of
about 1.5 to about 1.74. For compositions having two or more
refractive indices (e.g., compositions in which the refractive
index varies from place to place within the composition), a
composition is considered to have a refractive index in the range
of about 1.5 to about 1.74 if any one of the various refractive
indices is in the range of about 1.5 to about 1.74. Compositions
having two or more regions of refractive indices may be prepared by
controlling the degree of cure at various points within the
composition using, e.g., a photomask, digital mask (DLP) or
scanning laser as discussed above. Preferably, the photomask
permits various degrees of cure between full cure and no cure,
e.g., transmits various amounts of radiation as a function of
position within the photomask, thereby controlling the intensity of
transmitted radiation (and degree of cure) in any particular region
of the composition. Likewise, a scanning laser may be used to
selectively cure the polymer in a first region of the composition
to the extent desired in that first region, then scanned to a
second region to selectively cure the polymer in the second region
to a degree that is the same or different (as desired) than the
degree of cure in the first region, then scanned to a third region
to selectively cure the polymer in the third region to a degree
that is the same or different (as desired) than the degree of cure
in the first and/or second regions, etc.
[0065] It has been found that the stability of compositions
containing multiple regions having differing degrees of cure may be
influenced by various factors, including gravity (e.g., dense
regions tend to sink), diffusion (e.g., monomers tend to diffuse
faster than higher molecular weight components) and polymerization
(e.g., slow thermal polymerization of monomers and/or partially
cured regions at ambient temperature). In preferred embodiments,
one or more such stability issues are addressed, and compositions
having improved stability are provided, e.g., as demonstrated in
the examples below. Preferred compositions comprise a
polymerization inhibitor that is present in an amount effective to
at least partially inhibit polymerization of monomers and/or
partially cured regions of the composition.
[0066] In some cases the procurement of various monomers, polymers
and/or additives useful for making an optical element may be
inconvenient and/or costly. A preferred embodiment is directed to a
kit that comprises at least one container and one or more of the
components used to make the compositions described herein. For
example, a preferred kit comprises at least one container, a matrix
polymer, a thiol monomer, and a second monomer. Preferably, the
matrix polymer is a polyester, a polystyrene, a polyacrylate, an
epoxy polymer, an isocyanate polymer, or a mixture thereof.
Preferably, the second monomer is an ene monomer, yne monomer or
mixture thereof. In a preferred embodiment, a first container
comprises a thiol monomer, and a second container comprises a
second monomer (more preferably, selected from the group consisting
of ene monomer and yne monomer) and a matrix polymer (more
preferably, selected from the group consisting of polyester,
polystyrene, polyacrylate, epoxy polymer, isocyanate polymer, and
mixtures thereof). Preferred kits further comprise one or more
additives selected from the group consisting of photoinitiator,
polymerization inhibitor, antioxidant, photochromic dye, and/or
UV-absorber. Preferably, at least one material selected from the
group consisting of the matrix polymer, the thiol monomer and the
second monomer, has a refractive index in the range of about 1.5 to
about 1.74. More preferably, the matrix polymer, the thiol monomer
and the second monomer each have a refractive index in the range of
about 1.5 to about 1.74.
[0067] The compositions described herein may be used in a number of
applications. For example, preferred compositions are substantially
transparent to optical radiation, and thus are useful as optical
elements, e.g., eyeglass lenses, intraocular lenses, contact
lenses, and lenses used in various pieces of optical equipment. The
methods described herein enable the production of optical elements
in which the index of refraction at any particular point within the
element can be controlled. Such optical elements are useful in, for
example, the production of optical elements that correct
higher-order aberrations of the human eye, see, e.g., U.S. Pat. No.
6,712,466, and co-pending U.S. application Ser. No. (Attorney
Docket No. OPH.032A, entitled "Method of Manufacturing an Optical
Lens"), filed Sep. 7, 2004, both of which are hereby incorporated
by reference in their entireties.
[0068] Additional preferred embodiments provide polymerizable
compositions useful for making optical elements. These
polymerizable compositions are particularly useful for fabricating
optical elements using the methods described in U.S. patent
application Ser. No. 10/253,956, published as U.S. patent
application Publication No. 2004-008319 A1, both of which are
hereby incorporated by reference in their entireties. U.S. patent
application Publication No. 2004-0008319 A1 ("the '8319
publication") discloses, inter alia, techniques for making optical
elements using micro-jet printing methods to precisely control the
type, position and amount of polymer deposited onto a substrate. In
preferred embodiments, the proportions of two or more different
polymer compositions are varied over the course of the deposition
process to deposit adjoining polymer pixels in the form of a film
on the substrate surface. The optical properties of each adjoining
polymer pixel can be selected to provide a predetermined optical
property, including a specific value of index of refraction.
Preferably, the film has a radially non-monotonic refractive index
profile and/or an angularly non-monotonic refractive index
profile.
[0069] As described in the '8319 publication, preferred methods for
making optical elements involve the projection of two or more
polymer compositions onto pre-selected locations on a substrate.
The term "polymer composition," as used in the '8319 publication,
is a broad term that refers to a composition that comprises a
polymer, and the term "polymer" includes all forms of polymer and
their precursors, including polymerizable compositions such as
pre-polymers.
[0070] Polymerizable compositions have now been discovered that are
particularly well-suited for use in the methods described in the
'8319 publication, although they are useful for other applications
as well. Preferred polymerizable compositions comprise a first ene
monomer and a first thiol monomer together having a first
refractive index; and a second ene monomer and a second thiol
monomer together having a second refractive index; the difference
between the first refractive index and the second refractive index
being in the range of about 0.001 to about 0.5, preferably in the
range of about 0.001 to about 0.1. The monomers may be intermixed
in any order to form the polymerizable composition. The
polymerizable compositions are preferably made by preparing a high
index composition comprising the first ene monomer and a first
thiol monomer; preparing a low index composition comprising second
ene monomer and a second thiol monomer, and may involve intermixing
the high index composition and the low index composition to form
the polymerizable composition. The refractive indices of each of
the monomer pairs (e.g., the first refractive index of the first
ene monomer and the first thiol monomer together) are measured
apart from the polymerizable composition. To determine the
refractive index of the ene monomer and thiol monomer apart from
the polymerizable composition, a test sample is prepared which
contains the ene monomer and thiol monomer together in the same
relative proportions as in the polymerizable composition. The
refractive index of the test sample is then determined at
25.degree. C. Those skilled in the art will recognize that various
mixtures of the components are themselves polymerizable
compositions. For example, the first ene monomer and a first thiol
monomer together form a polymerizable composition, and likewise the
second ene monomer and the second thiol monomer together form a
second polymerizable composition.
[0071] The high index composition and the low index composition are
preferably intermixed by the methods described in the '8319
publication. For example, FIG. 1A of the '8319 publication
illustrates a preferred embodiment in which two polymer
compositions are projected onto a substrate using a spray unit 100
that is controlled by a computerized controller 105, the spray unit
100 comprising a first spray head 110 and a second spray head 115
(reference numbers refer to those used in the '8319 publication).
Preferably, the first spray head 110 contains or is charged with a
high index composition, and the second spray head 115 contains or
is charged with a low index composition. Intermixing of the high
and low index compositions to form a polymerizable composition may
then be conducted as described in the '8319 publication, e.g., by
projecting a first polymer droplet from the first spray head 110
onto a pre-selected location on the substrate 120 to form a first
deposited polymer droplet 125, projecting a second polymer droplet
130 from the second spray head 115 in close proximity to the first
deposited polymer droplet 125, and forming a first polymer pixel
135 by mixing the first deposited polymer droplet 125 and the
second polymer droplet 130. Thus, in this embodiment, the first
polymer pixel 135 comprises the polymerizable composition formed
from the high index composition (comprising the first ene monomer
and the first thiol monomer together having a first refractive
index, as measured apart from the polymerizable composition) and
the low index composition (comprising the second ene monomer and
the second thiol monomer together having a second refractive index,
as measured apart from the polymerizable composition). Preferably,
the difference between the first refractive index and the second
refractive index is in the range of about 0.001 to about 0.5,
preferably in the range of about 0.001 to about 0.1. The
polymerizable compositions may also be formed or used by other
methods described in the '8319 publication.
[0072] The refractive index of the polymerizable composition may be
varied over a broad range by varying the relative amounts of the
high index composition and the low index composition, and by
appropriate selection of the ene and thiol monomers themselves. The
ratio of high index composition to low index composition in the
polymerizable composition may vary over a broad range of from about
0:100 to about 100:0. Preferably, the ratio is selected by
considering the refractive index of the individual components,
using routine experimentation to confirm that the resulting mixture
provides the desired refractive index after polymerization.
Preferably, the relative amounts of ene and thiol monomers are
selected such that subsequent polymerization forms a polymer having
the desired physical properties, e.g., mechanical and optical
properties. More preferably, the relative amounts of ene and thiol
monomers in the polymerizable composition are such that the number
of ene functional groups is about equal to the number of thiol
groups.
[0073] A wide variety of ene and thiol monomers are useful for
making polymerizable compositions. The thiol and ene and yne
monomers shown in Tables 1 and 2 are preferred. The refractive
indices of preferred high and low index compositions are described
in the Examples below. The refractive indices of other high and low
index compositions may be determined by routine experimentation. In
any particular polymerizable composition, the first ene monomer may
be the same as the second ene monomer, or the first thiol monomer
may be the same as the second thiol monomer, so long as the first
ene monomer and the first thiol monomer together have a first
refractive index, as measured apart from the polymerizable
composition, and the second ene monomer and the second thiol
monomer together have a second refractive index, also as measured
apart from the polymerizable composition, such that the difference
between the first refractive index and the second refractive index
is in the range of about 0.001 to about 0.5, more preferably in the
range of about 0.001 to about 0.1. Preferably, the first ene
monomer is selected from the group consisting of styrene,
divinylbenzene,
##STR00013##
[0074] Preferably, the first thiol monomer and the second thiol
monomer in the polymerizable composition are selected from the
group consisting of thiobisbenezenethiol,
##STR00014##
[0075] Preferably, the second ene monomer is:
##STR00015##
[0076] The polymerizable composition may further comprise one or
more additives such as solvents, surfactants, crosslinking agents,
polymerization inhibitors, polymerization initiators, colorants,
flow control agents, and/or stabilizers. Preferably, the
polymerizable composition comprises one or more additives selected
from the group consisting of polymerization initiator (e.g.,
photoinitiator, thermal initiator), polymerization inhibitor,
antioxidant, photochromic dye, and UV-absorber.
[0077] In preferred embodiments the components of the polymerizable
composition are provided in the form of a kit. A preferred kit
comprises a first container comprising a high index composition
having a first refractive index, the high index composition
comprising a first ene monomer and a first thiol monomer; and a
second container comprising a low index composition having a second
refractive index, the low index composition comprising a second ene
monomer and a second thiol monomer, the difference between the
first refractive index and the second refractive index preferably
being in the range of about 0.001 to about 0.5, more preferably in
the range of about 0.001 to about 0.1. Thiol and ene monomers
useful in the kit are described above. The containers may further
comprise one or more additives such as crosslinking agents,
polymerization inhibitors, polymerization initiators, colorants,
flow control agents, and/or stabilizers as described above. The
size, shape and configuration of the containers may be varied as
needed to provide a convenient source of the components. For
example, the kit may be in the form of a cartridge adapted for use
in a polymer projection deposition system as described in the '8319
publication.
TABLE-US-00001 TABLE 1 No. Thiol Monomers 1 ##STR00016## 2
##STR00017## 3 ##STR00018## 4 ##STR00019## 5 ##STR00020## 6
##STR00021## 7 ##STR00022## Where R = --CH.sub.2CH.sub.2CH.sub.2SH,
or H 8 ##STR00023## 9 ##STR00024## 10 ##STR00025## 11 ##STR00026##
12 ##STR00027## 13 ##STR00028## 14 ##STR00029## 15 ##STR00030## 16
##STR00031##
TABLE-US-00002 TABLE 2 No. Ene and Yne Monomers 1 ##STR00032## 2
##STR00033## 3 ##STR00034## 4 ##STR00035## 5 ##STR00036## 6
##STR00037## 7 ##STR00038## 8 ##STR00039## 9 ##STR00040## Where R =
CH.sub.3, C.sub.4H.sub.9, or H 10 ##STR00041## 6 ##STR00042## 7
##STR00043## 8 ##STR00044## 9 ##STR00045## Where R = CH.sub.3,
C.sub.4H.sub.9, or H 10 ##STR00046## 11 ##STR00047## 12
##STR00048## 13 ##STR00049## 14
CH.sub.2.dbd.CHCH.sub.2O.sub.2COCH.sub.2CH.sub.2OCH.sub.2CH.sub.2OCO.su-
b.2CH.sub.2CH.dbd.CH.sub.2 15 ##STR00050## Where R =
--CH.sub.2CH.dbd.CH.sub.2, or H 16 ##STR00051## 17 ##STR00052## 18
##STR00053## 19 ##STR00054## 20 ##STR00055## 21 ##STR00056## 22
##STR00057## 23 ##STR00058## Hexafunctional urethane acrylate
ester(aliphatic), CN975 (from SARTOMER, circle represents
proprietary core structure) 24 ##STR00059## 25 ##STR00060## 26
##STR00061## 27 ##STR00062## Ebecryl 1290 (Aliphatic urethane
hexaacrylate) (from UCB Chemicals, circle represents proprietary
core structure) 28 ##STR00063## Ebecryl 220 (Aromatic urethane
hexaacrylate) (from UCB Chemicals, circle represents proprietary
core structure) 29 ##STR00064## Ebecryl 830 (Polyester
hexaacrylate) (from UCB Chemicals, square represents proprietary
core structure) 30 ##STR00065## Ebecryl 8301 (Aliphatic urethane
hexaacrylate) (from UCB Chemicals, square represents proprietary
core structure) 31 ##STR00066## 32 ##STR00067## 33 ##STR00068## 34
##STR00069## 35 ##STR00070## 36 ##STR00071## 37 ##STR00072## 38
##STR00073## 39 ##STR00074## 40 ##STR00075## 41 ##STR00076## 42
##STR00077## 43 ##STR00078## 44 ##STR00079## 45 ##STR00080## 46
##STR00081## 47 ##STR00082## 48 ##STR00083## 49 ##STR00084## 50
##STR00085## 51 ##STR00086## 52 ##STR00087## 53 ##STR00088## 54
##STR00089##
EXAMPLES
[0078] Materials: Starting materials were commercially available.
Pentaerythritol triallyl ether (70% triallyl) (ene monomer) and
trimethylolpropane tris(3-mercaptopropionate)(thiol monomer) were
obtained from Aldrich. Copolymer of Bisphenol A and fumaric acid
(ATLAC 382-E, (unsaturated polyester) was obtained from Reichhold.
The amine (1838-L 3M Scotch.TM. Weld (Part A)) was obtained from R.
S. Hughes. Irgacure.TM. 184 (photoinitiator) was obtained from
Ciba. N-PAL (polymerization inhibitor) was obtained from Albemarle.
ATLAC was dissolved in acetone, filtered through a 2.5.mu. filter
and stored in acetone and used as the acetone solution of ATLAC.
Poly[(phenyl glycidyl ether)-co-formaldehyde], an epoxy polymer
represented by the formula (III), and polyethyleneimine were
purchased from Aldrich. Diallylether Bisphenol A was obtained from
Bimax. Tetrabutyl ammonium bromide was obtained from Aldrich.
Acetone, HPLC grade, was obtained from Fisher Scientific.
Example 1
[0079] A kit having Parts I and II was made as follows:
[0080] Part I: In a labeled 100 mL bottle, 6.000 g of
pentaerythritol triallyl ether (70% triallyl), 13.000 g of
trimethylolpropane tris(3-mercaptopropionate), 13.000 g of ATLAC
(previously dissolved in acetone, filtered through a 2.5.mu.
filter, and dried), 0.0088 g N-PAL and 0.044 g of Irgacure.TM. 184
were weighed. Using a stirrer bar and a magnetic stirrer, the
ingredients was stirred for about 10 minutes to give a homogenous
mixture. The mixture was rotary evaporated at 50.degree. C. for 1-2
hours to evaporate all acetone.
[0081] Part II: In another labeled 30 mL amber vial, 4.000 g of
pentaerythritol triallyl ether (70% triallyl), 8.000 g of
trimethylolpropane tris(3-mercaptopropionate), and 0.528 g of amine
(1838-L 3M Scotch.TM. Weld (Part A)) were weighed. Using a stirrer
bar and a magnetic stirrer, the formulation was stirred for about
10 minutes to give a homogenous mixture.
Example 2
[0082] A portion of Parts I and II (from the kit of Example 1) were
mixed in a ratio of 2.53:1, respectively. The Part I composition
was weighed carefully in a 100 mL beaker. Based on the amount of
Part I formulation, the calculated amount of Part II was added into
the same beaker. The two compositions were first mixed thoroughly
by hand using a glass stirrer (glass was found to work better than
metal), followed by mixing using a magnetic stirrer to form a
mixture, then used immediately as described in Example 3.
Example 3
[0083] The mixture of Example 2 was transferred to a glass plate
equipped with a wire spacer. The mixture on the plate was degassed
to remove trapped air. A thin glass plate was carefully placed over
the glass plate and the plates were pressed firmly together, with
the degassed mixture sandwiched between. The sandwiched mixture was
cured by exposing it to ultraviolet light using a UV lamp (EXFO
intensity=16.6 mW/cm.sup.2) for 5 minutes. The difference in the
refractive index between the sandwiched mixture and the cured film
was measured to be 0.024.
Example 4
[0084] The mixture of Example 2 was transferred to a glass plate
equipped with a wire spacer. The mixture on the plate was degassed
to remove trapped air. A thin glass plate was carefully placed over
the glass plate and the plates were pressed firmly together, with
the degassed mixture sandwiched between. The sandwiched mixture was
maintained at about 60.degree. C. for about 40 minutes to form a
sandwiched gel. The gel comprised a thiol-cured polyester polymer
having pentaerythritol triallyl ether (70% triallyl),
trimethylolpropane tris(3-mercaptopropionate) dispersed therein.
The sandwiched gel was masked and the central portion of the gel
was exposed to ultraviolet radiation (EXFO intensity=16.6
mW/cm.sup.2) for about 5 minutes at about 80.degree. C. to
polymerize the ene and thiol monomers, thereby forming a mixture of
a thiol-ene polymer and a crosslinked polyester in the exposed
region. The difference in the refractive index between the masked
and unmasked regions was measured to be 0.0181.
Example 5
[0085] The mask was removed from the sandwiched gel of Example 4
and the entire sandwiched gel between the two plates was exposed to
ultraviolet radiation (EXFO intensity=4.8 mW/cm.sup.2) at room
temperature for about 2 minutes, thereby partially polymerizing the
thiol and ene monomers in the area previously under the mask. The
refractive index difference between the previously masked region
and the unmasked region was 0.014. This period of exposure was
found to provide increased stability of the refractive index
difference between the masked and unmasked regions.
Example 6
##STR00090##
[0087] Synthesis of 1,1,1 tris(4-allyloxy-phenyl)ethane: In a 500
mL three neck-round bottom flask equipped with condenser, magnetic
stirring bar, dropping funnel, and Argon inlet, 15.00 g (49 mmol)
of 1,1,1 tris(4-hydroxy-phenyl)ethane was dissolved in a 1:1
mixture of methylene chloride and tetrahydrofuran. To this mixture,
a solution of sodium hydroxide 10.70 g (267 mmol) dissolved in 60
mL of distilled water was added while vigorously stirring. Allyl
bromide, 33.36 g (276 mmol) was added followed by 2.5 g (5.96 mmol)
tetraphenylphosphoniumbromide catalyst. The reaction mixture was
left under positive pressure of Argon while stirring at room
temperature. The reaction was monitored by TLC and stopped after 36
hours. The reaction mixture was transferred into separatory funnel
and the product was extracted twice with 200 mL of methylene
chloride. The organic layers were combined and extensively washed
several times with distilled water. The organic extract was dried
over anhydrous magnesium sulfate and filtered using Whatman filter
paper. To this filtrate, activated charcoal was added and the
mixture was stirred for 12 h. The charcoal was filtered and the
solvent was evaporated using rotary evaporator. The resulting
viscous compound was purified through column chromatography using
silica as stationary phase and methylene chloride as an eluent. The
solvent was removed using rotary evaporator to yield 14.50 g (70%)
of clear, colorless, viscous liquid of 1,1,1
tris(4-allyloxy-phenyl)ethane. .sup.1H NMR and IR spectra were
consistent with 1,1,1 tris(4-allyloxy-phenyl)ethane. .sup.1H NMR
(CDCl.sub.3): 4.58 (m, CH.sub.20, 6H), 2.17 (s, --CH.sub.3), 5.2
(m, .dbd.CH2, 6H), 6.1 (m, .dbd.CH, 3H), 6.81 (dd, 6 aromatic H
ortho to OR), 7.03 (dd, 6 aromatic H meta to OR). IR (NaCl): Major
bands at 1293 cm.sup.-1 (aromatic ether), 2912 cm.sup.-1 (aliphatic
hydrocarbon), and 1648 cm.sup.-1 (unsaturated hydrocarbon).
Example 7
[0088] A kit having Parts I and II was made as follows:
[0089] Part 1: In a labeled 100 mL bottle, 10.00 g of poly[(phenyl
glycidyl ether)-co-formaldehyde], 10.89 g of trimethylolpropane
tris(3-mercaptopropionate), 2.30 g of pentaerythritol triallyl
ether, 0.0056 g N-PAL, and 0.0281 g of Irgacure.TM. 184 were
weighed. Acetone was added to dissolve the ingredients. Using a
stirrer bar and a magnetic stirrer, the ingredients were stirred
for about 10 minutes to give a homogenous mixture. The mixture was
rotary evaporated at 50.degree. C. for 1-2 hours to evaporate all
acetone.
[0090] Part II: In another labeled 30 mL amber vial, 2.3689 g of
pentaerythritol triallyl ether, 2.5782 g of trimethylolpropane
tris(3-mercaptopropionate), and 0.7034 g of polyethyleneimine were
weighed. Using a stirrer bar and a magnetic stirrer, the
formulation was stirred for about 10 minutes with gentle heating to
give a homogenous mixture.
Example 8
[0091] A portion of Parts I and II (from the kit of Example 7) were
mixed in a ratio of 4.10:1, respectively. The Part I composition
was weighed carefully in a 100 mL beaker. Based on the amount of
Part I formulation, the calculated amount of Part II was added into
the same beaker. The two compositions were first mixed thoroughly
by hand using a glass stirrer (glass was found to work better than
metal), followed by mixing using a magnetic stirrer to form a
mixture having a refractive index of 1.5316, then used immediately
as described in Example 9.
Example 9
[0092] The mixture of Example 8 was transferred to a glass slide (1
mm thick) equipped with a spacer (20 mil diameter wire around the
edges of the slide). The mixture on the slide was degassed to
remove trapped air. Another glass slide was carefully placed over
the first glass slide, and the plates were pressed firmly together
with the degassed mixture sandwiched between. The sandwiched
mixture was maintained at about 65.degree. C. for about 5.5 hours
to form a sandwiched gel. The gel comprised a crosslinked epoxy
polymer having pentaerythritol triallyl ether and
trimethylolpropane tris(3-mercaptopropionate) dispersed therein,
and having a refractive index of 1.5550.
Example 10
[0093] The sandwiched gel made in Example 9 was masked and the
central portion of the gel was exposed to ultraviolet radiation
(EXFO intensity=100 mW/cm.sup.2) for about 10 minutes at about
90.degree. C. to polymerize the ene and thiol monomers, thereby
forming a mixture of a thiol-ene polymer and a crosslinked epoxy in
the exposed region. The central irradiated region had a refractive
index of 1.5668, and the masked outer region had a refractive index
of 1.5550 (difference in refractive index between the masked and
unmasked regions of 0.0118). The difference between the unmasked
region and the mixture made of formulation described in Example 8
was 0.0352.
Example 11
[0094] A kit having Parts I and II was made as follows:
[0095] Part 1: In a labeled 100 mL bottle, 6.000 g of
pentaerythritol triallyl ether (70% triallyl), 13.000 g of
trimethylolpropane tris(3-mercaptopropionate), 13.000 g of ATLAC
(previously dissolved in acetone, filtered through a 2.5.mu.
filter, and dried), and 0.044 g of Irgacure.TM. 184 were weighed.
Using a stirrer bar and a magnetic stirrer, the ingredients was
stirred for about 10 minutes to give a homogenous mixture. The
mixture was rotary evaporated at 50.degree. C. for 1-2 hours to
evaporate all acetone.
[0096] Part II: In another labeled 30 mL amber vial, 4.000 g of
pentaerythritol triallyl ether (70% triallyl), 8.000 g of
trimethylolpropane tris(3-mercaptopropionate), and 0.660 g of amine
(1838-L 3M Scotch Weld (Part A)) were weighed. Using a stirrer bar
and a magnetic stirrer, the formulation was stirred for about 10
minutes to give a homogenous mixture.
Example 12
[0097] A portion of Parts I and II (from the kit of Example 11)
were mixed in a ratio of 2.53:1, respectively. The Part I
composition was weighed carefully in a 100 mL beaker. Based on the
amount of Part I formulation, the calculated amount of Part II was
added into the same beaker. The two compositions were first mixed
thoroughly by hand using a glass stirrer (glass was found to work
better than metal), followed by mixing using a magnetic stirrer to
form a mixture, then used immediately as described in Example
13.
Example 13
[0098] The mixture of Example 12 was transferred to a glass plate
equipped with a wire spacer. The mixture on the plate was degassed
to remove trapped air. A thin quartz plate was carefully placed
over the glass plate and the plates were pressed firmly together,
with the degassed mixture sandwiched between. The sandwiched
mixture was cured by exposing it to ultraviolet light using a UV
lamp (EXFO intensity=1.5-2.0 mW/cm.sup.2) for 30 minutes. The
difference in the refractive index between the fully cured and the
sandwiched mixture was measured to be 0.025.
Example 14
[0099] The mixture of Example 12 was transferred to a glass plate
equipped with a wire spacer. The mixture on the plate was degassed
to remove trapped air. A thin quartz plate was carefully placed
over the glass plate and the plates were pressed firmly together,
with the degassed mixture sandwiched between. The sandwiched
mixture was maintained at about 60.degree. C. for about 40 minutes
to form a sandwiched gel. The gel comprised a crosslinked polyester
polymer having pentaerythritol triallyl ether (70% triallyl) and
trimethylolpropane tris(3-mercaptopropionate) dispersed therein.
The sandwiched gel was masked and the central portion of the gel
was exposed to ultraviolet radiation (EXFO intensity=8-10
mW/cm.sup.2) for about 5 minutes to polymerize the ene and thiol
monomers, thereby forming a mixture of a thiol-ene polymer and a
crosslinked polyester in the exposed region. The difference in the
refractive index between the masked and unmasked regions was
measured to be 0.020.
Example 15
[0100] The mask was removed from the sandwiched gel of Example 14
and the entire sandwiched gel between the two plates was exposed to
ultraviolet radiation (EXFO intensity=8-10 mW/cm.sup.2) for about
2-5 minutes, thereby partially polymerizing the thiol and ene
monomers in the area previously under the mask. The refractive
index difference between the previously masked region and the
unmasked region was 0.007. This period of exposure was found to
provide increased stability of the refractive index difference
between the masked and unmasked regions.
Example 16
[0101] The process described in Examples 12, 14 and 15 is repeated,
except that additional amounts of pentaerythritol triallyl ether
(70% triallyl) and trimethylolpropane tris(3-mercaptopropionate)
are added to the unexposed region of a sandwiched gel prepared as
described in Example 14. The resulting sandwiched gel, containing
the additional monomers, is then exposed to ultraviolet radiation
in the manner described in Example 15, thereby partially
polymerizing the thiol and ene monomers in the unmasked area. The
refractive index difference between the previously masked region
and the unmasked region is greater than 0.007 because of the
presence of the additional monomers.
Example 17
[0102] A kit having Parts I and II was made as follows:
[0103] Part I: In a 500 mL flask, 100 g of poly[(phenylglycidyl
ether)-co-formaldehyde], 49.42 g of diallylether Bisphenol A,
0.2761 g of Irgacure.TM. 184, and 0.0552 g of N-PAL were dissolved
in acetone. The mixture was then filtered through a 0.2 .mu.m
syringe filter into another clean 500 mL flask. The filtrate was
rotary evaporated at 60.degree. C. for 2 hours to evaporate all
acetone.
[0104] Part II: In another 500 mL flask, 3.27 g of tetrabutyl
ammonium bromide, and 150 g of trimethylolpropane
tris(3-mercaptopropionate) were dissolved in acetone. The mixture
was then filtered through a 0.2 .mu.m syringe filter into another
clean 500 mL flask. The filtrate was rotary evaporated at
50.degree. C. for 2 hours to evaporate all acetone.
Example 18
[0105] A portion of Parts I and 1: (from the kit of Example 17)
were mixed in a ratio of 1.157:1, respectively. The Part I
composition was weighed carefully in a 20 mL scintillation vial.
Based on the amount of Part I formulation, the calculated amount of
Part II was added to the same vial. The two compositions were mixed
thoroughly by hand using a glass stirring rod.
Example 19
[0106] Approximately 2.6 grams of the mixture of Example 18 was
transferred to the concave surface of a Samsung EyeTech UV-Clear
1.6 cover 210 (schematically illustrated in FIG. 2) equipped with
spacers 220 (pieces of adhesive tape with 20 mil thickness placed
around the edges on the concave side of the cover lens). The
mixture 230 on the cover 210 was degassed to remove trapped air. A
Samsung UV-Clear 1.6 base lens 240 with a 5.0 base curve was
carefully placed over the cover lens and the lenses were pressed
firmly together, with the degassed mixture 230 sandwiched between
to make a lens assembly 250 (schematically illustrated in FIG. 3).
The lens assembly 250 was maintained at 75.degree. C. for 51/2
hours to cure the sandwiched mixture 230 to a gel. The gel 230
comprised a thiol-cured epoxy having diallylether Bisphenol A and
trimethylolpropane tris(3-mercaptopropionate) dispersed therein.
After the lens assembly 250 was cooled to room temperature, the
base lens 240 was then ground to plano to form an optical
element.
Example 20
[0107] The lens assembly 250 of Example 19 was placed inside a hot
box with a lens holder in order to heat the lens assembly to a
temperature of 85.degree. C. A ZYGO interferometer was used to
measure the optical path difference (OPD) pattern of the lens
assembly prior to UV exposure. This OPD pattern was designated as
the reference OPD pattern. A Dymax UV lamp with an integrating rod
was used to produce a uniform beam of ultraviolet radiation
(Intensity=53 mW/cm.sup.2). The central region of the sandwiched
gel 230 in the lens assembly 250 was exposed to ultraviolet
radiation through a photomask with a trefoil pattern (FIG. 4) for
22 minutes. A ZYGO interferometer was used to measure the OPD
pattern created in the sandwiched gel 230 as a result of the
ultraviolet exposure through the trefoil photomask. The reference
OPD pattern was subtracted from the new OPD pattern, and
Intelliwave software was used to create an OPD map (FIG. 5). A
peak-to-valley range of 3.27 microns (corresponding to a refractive
index difference of 0.01 between the irradiated and masked regions,
sufficient to correct higher order aberrations of a large
percentage of the population) was obtained over a 6 mm diameter in
the central region of the lens.
Example 21
[0108] A kit having Parts I and II was made as follows:
[0109] Part I: In a 500 mL flask, 100 g of poly[(phenylglycidyl
ether)-co-formaldehyde], 33.61 g of diallylether Bisphenol A,
0.2466 g of Irgacure.TM. 184, and 0.0740 g of N-PAL were dissolved
in acetone. The mixture was then filtered through a 0.2 .mu.m
syringe filter into another clean 500 mL flask. The filtrate was
rotary evaporated at 60.degree. C. for 2 hours to evaporate all
acetone.
[0110] Part II: In another 500 mL flask, 3.27 g of tetrabutyl
ammonium bromide, and 150 g of trimethylolpropane
tris(3-mercaptopropionate) were dissolved in acetone. The mixture
was then filtered through a 0.2 .mu.m syringe filter into another
clean 500 mL flask. The filtrate was rotary evaporated at
50.degree. C. for 2 hours to evaporate all acetone.
Example 22
[0111] Portions of parts I and II (from the kit of Example 21) were
mixed in a ratio of 1.16:1, respectively. The Part I composition
was weighed carefully in a 20 mL scintillation vial. Based on the
amount of Part I formulation, the calculated amount of Part II was
added to the same vial. The two compositions were mixed thoroughly
by hand using a glass stirring rod. The mixture was degassed to
remove trapped air.
Example 23
[0112] Approximately 0.3 grams of the mixture of Example 22 was
transferred to a 1-inch.times.1-inch square glass plate equipped
with spacers (pieces of adhesive tape with 20 mil thickness placed
at the corners of the square). Another 1-inch.times.1-inch square
quartz plate was carefully placed over the first glass plate and
the two plates were pressed firmly together, with the degassed
mixture sandwiched between to make a test cell. The cell was
maintained at 75.degree. C. for 51/2 hours to cure the sandwiched
mixture to a gel. The gel comprised a thiol-cured epoxy having
diallylether Bisphenol A and trimethylolpropane
tris(3-mercaptopropionate) dispersed therein.
Example 24
[0113] The test cell from Example 23 was placed inside of a hot box
with a cell holder in order to heat the cell to a temperature of
85.degree. C. A ZYGO interferometer was used to measure the optical
path difference (OPD) pattern of the lens assembly prior to UV
exposure. This OPD pattern was designated as the reference OPD
pattern. A Dymax UV lamp with an integrating rod was used to
produce a uniform beam of ultraviolet radiation (Intensity=53
mW/cm.sup.2). The central region of the sandwiched gel in the lens
assembly was exposed to ultraviolet radiation through a photomask
with a trefoil pattern (FIG. 4) for 31/2 minutes. After the
irradiation, the test cell was cooled to room temperature. A ZYGO
interferometer was used to measure the OPD pattern created in the
sandwiched gel as a result of the ultraviolet exposure through the
trefoil photomask. The reference OPD pattern was subtracted from
the new OPD pattern, and Intelliwave software was used to create an
OPD map. A peak-to-valley range of 1.6 microns was obtained over a
6 mm diameter in the central region of the test cell. This was
approximately half of the maximum potential peak-to-valley range
(2.96 microns as obtained in another test cell) for the test
cell.
Example 25
[0114] Accelerated thermal aging tests were performed on the test
cell irradiated as described in Example 24 in order to evaluate the
stability of the trefoil pattern that was written in the sandwiched
gel material. An assumption was made that there would be a doubling
in degradation rate for every 10.degree. C. increase in temperature
(typical assumption for accelerated aging study). Room temperature
in the laboratory was measured to be 23.degree. C., and the test
cell from Example 24 was kept in an oven at 83.degree. C. (a
difference of 60.degree. C.). According to the assumption,
degradation would occur 64 (or 26) times faster at 83.degree. C.
than at 23.degree. C. (room temperature). Thus, it was calculated
that aging the test cell in the oven at 83.degree. C. for 2 hours
and 38 minutes would simulate aging it at room temperature for one
week (168 hours). The test cell was kept in the oven at 83.degree.
C., and pulled out of the oven for brief periods at various times
to measure the OPD pattern using the ZYGO interferometer. The test
cell was cooled to room temperature prior to every measurement.
After each measurement, the new OPD pattern was compared to the
original OPD pattern obtained in Example 24 in order to quantify
the change of the OPD pattern due to accelerated thermal exposure.
FIG. 6 shows a plot of the percent change in peak-to-valley for the
trefoil pattern versus simulated time (2 hrs. 38 min. at 83.degree.
C.=1 simulated week at 23.degree. C.). The plot shows that the
peak-to-valley increased slightly above the original value at
first, and then decreased to about 81% of the original value
(degradation of only 19%) over a 2-year simulation.
Example 26
[0115] Accelerated thermal aging tests were performed on the Part I
formulation of the kit of Example 21 in order to evaluate its
stability. It was assumed that there would be a doubling in aging
rate for every 10.degree. C. increase in temperature (typical
assumption for accelerated aging study). The original refractive
index of the Part I formulation measured at room temperature was
1.5891. The Part I formulation was kept in an oven at 83.degree. C.
for 274 hours to simulate 2 years of aging at room temperature
according to the assumption. After two years of simulated aging,
the Part I formulation was removed from the oven, and cooled to
room temperature. Its refractive index was measured to be 1.5891 (a
change of 0% from the original value).
Example 27
[0116] The accelerated thermal aging test of Example 26 was
performed on the Part II formulation of the kit of Example 21 in
order to evaluate its stability. The original refractive index of
the Part H formulation was 1.5167. After a 2-year simulation, the
refractive index of the Part II formulation had increased to 1.5188
(a change of only 0.14% from the original value).
Example 28
[0117] The accelerated thermal aging test of Example 26 was
performed on the sandwiched gel of Example 23 to evaluate its
stability. The original refractive index of the sandwiched gel was
1.5758. After a 2-year simulation, the refractive index of the
sandwiched gel was still 1.5758 (a change of 0% from the original
value).
Example 29
[0118] The mixture of Example 8 was used to make two lens
assemblies prepared as described in Example 19 (except UV-Clear
CR-39 was used in place of Samsung EyeTech UV-Clear 1.6 for the
cover and base lenses). The two lens assemblies were used in an
experiment to evaluate the shelf-life of the sandwiched gel. One
lens assembly was stored at room temperature for 2 months and then
irradiated using the setup described in Example 20. A
peak-to-valley range (or dynamic range) of 4.11 microns was
obtained for the trefoil pattern after about 20 minutes of
irradiation. The second lens assembly was stored at room
temperature for 6 months and then irradiated using the setup
described in Example 20. A peak-to-valley range (or dynamic range)
of 4.57 microns was obtained for the trefoil pattern after about 18
minutes of irradiation. The curing curves (peak-to-valley vs. time)
for the two lenses of this example are shown in FIG. 7. The
achievement of approximately similar peak-to-valley range (or
dynamic range) and curing curves for each lens demonstrated that
the sandwiched gel of this example has a shelf-life of at least 6
months. This has important practical implications as it means that
lens assemblies with this sandwiched gel can be manufactured,
stored and/or distributed, and then custom-irradiated (with a
pattern that corresponds to a patient's unique high order
aberration) at a later time without sacrificing the magnitude
(peak-to-valley range) of the correction that can be written.
Example 30
[0119] A kit having Parts I and II was made by intermixing the
following ingredients:
[0120] Part I: 23.0 g of reactive Bisphenol A glycerolate (1
glycerol/phenol)diacrylate (BPGDA, n.sub.D=1.557) (Aldrich), 46.0 g
of ethanol (Aldrich), 0.23 g of photoinitiator (Irgacure.TM.
184).
[0121] Part II: 25.0 g of reactive 2-hydroxy ethyl methacrylate
(HEMA, n.sub.D=1.453) (Aldrich), 25.0 g of ethanol, 0.25 g of
photoinitiator (Irgacure.TM. 184).
Examples 31-36
[0122] A series of polymerizable compositions were prepared by
intermixing the relative amounts (weight basis) of Parts I and II
of the kit of Example 30 as shown in Table 3. Table 3 also shows
the refractive indices (n.sub.D) of each polymerizable composition
and the corresponding refractive indices of the polymers obtained
by UV-curing each of the polymerizable compositions.
TABLE-US-00003 TABLE 3 Composition No. Part II (%) Part I (%)
n.sub.D (uncured) n.sub.D (cured) 31 0 100 1.417 1.558 32 20 80
1.413 1.535 33 40 60 1.411 1.516 34 60 40 1.407 1.504 35 80 20
1.405 1.483 36 100 0 1.404 1.474
Example 37
[0123] A kit having Parts I and II was made by intermixing the
following ingredients:
[0124] Part I: 50.0 g of reactive tri(propylene glycol) diacrylate
(TPGDA, n.sub.D=1.450) (Aldrich), 50.0 g of ethanol, 0.51 g of
photoinitiator, Irgacure.TM. 184, and 0.52 g of thermal initiator,
azoisobutyronitrile (AIBN) (Aldrich).
[0125] Part II: 162.8 g of reactive Bisphenol A glycerolate (1
glycerol/phenol)diacrylate (BPGDA, n.sub.D=1.557), 162.8 g of
ethanol, 1.63 g of photoinitiator, Irgacure.TM. 184, and 1.63 g of
thermal initiator, azoisobutyronitrile (AIBN).
Examples 38-43
[0126] A series of polymerizable compositions were prepared by
intermixing the relative amounts (weight basis) of Parts I and II
of the kit of Example 37 as shown in Table 4. Table 4 also shows
the refractive indices (n.sub.D) of each polymerizable composition
and the corresponding refractive indices of the polymers obtained
by thermal/UV curing each of the polymerizable compositions.
TABLE-US-00004 TABLE 4 Composition No. Part II (%) Part I (%)
n.sub.D (uncured) n.sub.D (cured) 38 0 100 1.4497 1.5595 39 20 80
1.4365 1.5431 40 40 60 1.4286 1.5302 41 60 40 1.4214 1.5203 42 80
20 1.4120 1.4725 43 100 0 1.4045 1.4560
Example 44
[0127] A kit having Parts I and II was made by intermixing the
following ingredients:
[0128] Part I: An ene and a thiol of the following structures, 1%
Irgacure.TM. 184 and 1% Irgacure.TM. 819:
##STR00091##
[0129] Part II: An ene and a thiol of the following structures, 1%
Irgacure.TM. 184 and 1% lrgacure.TM. 819:
##STR00092##
Examples 45-50
[0130] A series of polymerizable compositions were prepared by
intermixing the relative amounts (weight basis) of Parts I and II
of the kit of Example 44 as shown in Table 5. Table 5 also shows
the refractive indices (n.sub.D) of each polymerizable composition
and the corresponding refractive indices of the polymers obtained
by UV-curing each of the polymerizable compositions.
TABLE-US-00005 TABLE 5 Composition No. Part II (%) Part I (%)
n.sub.D (uncured) n.sub.D (cured) 45 100 0 1.6150 1.6405 46 80 20
1.5882 1.6152 47 60 40 1.5618 1.5889 48 40 60 1.5370 1.5652 49 20
90 1.5105 1.5403 50 0 100 1.4895 1.5205
Example 51
[0131] A kit having Parts I and II was made by intermixing the
following ingredients:
[0132] Part I: Styrene, divinylbenzene, thiobisbenezenethiol, 1%
Irgacure.TM. 184 and 1% Irgacure.TM. 819.
[0133] Part II: An ene and a thiol of the following structures, 1%
Irgacure.TM. 184 and 1% Irgacure.TM. 819:
##STR00093##
Examples 52-57
[0134] A series of polymerizable compositions were prepared by
intermixing the relative amounts (weight basis) of Parts I and II
of the kit of Example 51 as shown in Table 6. Table 6 also shows
the refractive indices (n.sub.D) of each polymerizable composition
and the refractive index of the one of the polymers obtained by
UV-curing a polymerizable composition.
TABLE-US-00006 TABLE 6 Composition No. Part II (%) Part I (%)
n.sub.D (uncured) n.sub.D (cured) 52 100 0 1.6733 HAZY 53 80 20
1.6396 HAZY 54 60 40 1.6030 HAZY 55 40 60 1.5692 HAZY 56 20 90
1.5332 HAZY 57 0 100 1.4850 1.5125
Example 58
[0135] A kit having Parts I and II was made by intermixing the
following ingredients:
[0136] Part I: An ene prepared as in Example 6, a thiol of the
following structure, 1% Irgacure.TM. 184 and 1% Irgacure.TM.
819:
##STR00094##
[0137] Part II: An ene and a thiol of the following structures, 1%
Irgacure.TM. 184 and 1% Irgacure.TM. 819:
##STR00095##
Examples 59-64
[0138] A series of polymerizable compositions were prepared by
intermixing the relative amounts (weight basis) of Parts I and II
of the kit of Example 58 as shown in Table 7. Table 7 also shows
the refractive indices (n.sub.D) of each polymerizable composition
and the corresponding refractive indices of the polymers obtained
by UV-curing each of the polymerizable compositions.
TABLE-US-00007 TABLE 7 Composition No. Part II (%) Part I (%)
n.sub.D (uncured) n.sub.D (cured) 59 100 0 1.5608 1.5927 60 80 20
1.5421 1.5772 61 60 40 1.5291 1.5637 62 40 60 1.5123 1.5474 63 20
90 1.4980 1.5319 64 0 100 1.4852 1.5170
Example 65
[0139] A kit having Parts I and II was made by intermixing the
following ingredients:
[0140] Part I: An ene and a thiol of the following structures, 1%
Irgacure.TM. 184 and 1% Irgacure.TM. 819:
##STR00096##
[0141] Part II: An ene and a thiol of the following structures, 1%
Irgacure.TM. 184 and 1% Irgacure.TM. 819:
##STR00097##
Examples 66-71
[0142] A series of polymerizable compositions were prepared by
intermixing the relative amounts (weight basis) of Parts I and II
of the kit of Example 65 as shown in Table 8. Table 8 also shows
the refractive indices (n.sub.D) of each polymerizable composition
and the corresponding refractive indices of the polymers obtained
by UV-curing each of the polymerizable compositions.
TABLE-US-00008 TABLE 8 Composition No. Part II (%) Part I (%)
n.sub.D (uncured) n.sub.D (cured) 66 100 0 1.5742 1.6124 67 80 20
1.5542 1.5962 68 60 40 1.5371 1.5763 69 40 60 1.5182 1.5547 70 20
90 1.5009 1.5341 71 0 100 1.4852 1.5170
Example 72
[0143] A kit having Parts I and II was made by intermixing the
following ingredients:
[0144] Part I: An ene as prepared in Example 6, an ene and a thiol
of the following structures, and 1% Irgacure.TM. 184:
##STR00098##
[0145] Part II: An ene and a thiol of the following structures, 1%
Irgacure.TM. 184 and 1% Irgacure.TM. 819:
##STR00099##
Examples 73-78
[0146] A series of polymerizable compositions were prepared by
intermixing the relative amounts (weight basis) of Parts I and II
of the kit of Example 72 as shown in Table 9. Table 9 also shows
the refractive indices (n.sub.D) of each polymerizable composition
and the corresponding refractive indices of the polymers obtained
by UV-curing each of the polymerizable compositions.
TABLE-US-00009 TABLE 9 Composition No. Part II (%) Part I (%)
n.sub.D (uncured) n.sub.D (cured) 73 100 0 1.4802 1.5121 74 80 20
1.4990 1.5300 75 60 40 1.5120 1.5423 76 40 60 1.5306 1.5654 77 20
90 1.5502 1.5847 78 0 100 1.5674 1.5905
Example 79
[0147] A kit having Parts I and II was made by intermixing the
following ingredients:
[0148] Part I: An ene as prepared in Example 6 (18 g), a thiol of
the following structure (10.98 g), Brij 52 (Aldrich) (surfactant,
0.02 g), Brij 58 (Aldrich) (surfactant, 0.02 g), Irgacure.TM. 184
(0.161 g) and Irgacure.TM. 819 (0.119 g):
##STR00100##
[0149] Part II: An ene (50 g) and a thiol (32.66 g) of the
following structures, Irgacure.TM. 184 (0.27 g):
##STR00101##
Examples 80-85
[0150] A series of polymerizable compositions were prepared by
intermixing the relative amounts (weight basis) of Parts I and II
of the kit of Example 79 as shown in Table 10. Table 10 also shows
the refractive indices (n.sub.D) of each polymerizable composition
and the corresponding refractive indices of the polymers obtained
by UV-curing each of the polymerizable compositions.
TABLE-US-00010 TABLE 10 Composition No. Part II (%) Part I (%)
n.sub.D (uncured) n.sub.D (cured) 80 100 0 1.4820 1.5104 81 80 20
1.5094 1.5380 82 60 40 1.5327 1.5648 83 40 60 1.5571 1.5906 84 20
90 1.5786 1.6150 85 0 100 1.6004 1.6405
[0151] It will be appreciated by those skilled in the art that
various omissions, additions and modifications may be made to the
processes described above without departing from the scope of the
invention, and all such modifications and changes are intended to
fall within the scope of the invention, as defined by the appended
claims.
* * * * *