U.S. patent application number 13/939115 was filed with the patent office on 2013-11-07 for custom monomers and polymers for spectacle lenses.
The applicant listed for this patent is Gomaa ABDEL-SADEK, Erdem CETIN, Jeffrey CHOMYN, Junhao GE, Jagdish JETHMALANI, Shawn MCCARTY, Lawrence H. SVERDRUP. Invention is credited to Gomaa ABDEL-SADEK, Erdem CETIN, Jeffrey CHOMYN, Junhao GE, Jagdish JETHMALANI, Shawn MCCARTY, Lawrence H. SVERDRUP.
Application Number | 20130296452 13/939115 |
Document ID | / |
Family ID | 38327069 |
Filed Date | 2013-11-07 |
United States Patent
Application |
20130296452 |
Kind Code |
A1 |
JETHMALANI; Jagdish ; et
al. |
November 7, 2013 |
Custom Monomers and Polymers for Spectacle Lenses
Abstract
Monomers and polymers used in making spectacle lenses are
disclosed. A thermal curing process is disclosed that includes a
latent thermal cationic acid generator and optionally a cationic
photoinitiator.
Inventors: |
JETHMALANI; Jagdish; (San
Diego, CA) ; ABDEL-SADEK; Gomaa; (San Diego, CA)
; CHOMYN; Jeffrey; (San Diego, CA) ; CETIN;
Erdem; (San Diego, CA) ; SVERDRUP; Lawrence H.;
(Poway, CA) ; MCCARTY; Shawn; (San Diego, CA)
; GE; Junhao; (Los Angeles, CA) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
JETHMALANI; Jagdish
ABDEL-SADEK; Gomaa
CHOMYN; Jeffrey
CETIN; Erdem
SVERDRUP; Lawrence H.
MCCARTY; Shawn
GE; Junhao |
San Diego
San Diego
San Diego
San Diego
Poway
San Diego
Los Angeles |
CA
CA
CA
CA
CA
CA
CA |
US
US
US
US
US
US
US |
|
|
Family ID: |
38327069 |
Appl. No.: |
13/939115 |
Filed: |
July 10, 2013 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
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11726055 |
Mar 20, 2007 |
|
|
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13939115 |
|
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|
|
60784394 |
Mar 20, 2006 |
|
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Current U.S.
Class: |
522/31 ; 522/168;
522/170; 528/409; 528/417; 528/421 |
Current CPC
Class: |
G02B 5/208 20130101;
G02B 3/0087 20130101; B29D 11/00355 20130101; G02C 2202/16
20130101; G02B 1/041 20130101; G02C 2202/12 20130101 |
Class at
Publication: |
522/31 ; 528/417;
528/421; 522/170; 522/168; 528/409 |
International
Class: |
G02B 1/04 20060101
G02B001/04 |
Claims
1. A method of making an optical element by forming a polymer layer
employing a thermally initiated cationic ring opening
polymerization reaction which comprises: a. mixing one or more
monomers and a thermal initiator, b. forming a layer of the mixture
of (a) and c. heating the layer to cure it.
2. The method of claim 1 wherein the monomer is an epoxy, an
oxetane or mixtures thereof.
3. The method of claim 1 further comprising adding a photoinitiator
to the mixture of (a).
4. The method of claim 3 wherein the photoinitiator is an
arylsulfonium, alkylsulfonium, or aryliodonium photo acid
generator.
5. The method of claim 1 wherein the thermal initiator is a latent
thermal cationic acid generator.
6. The method of claim 5 wherein the latent thermal cationic acid
generator is ammonium hexafluoroantimonate.
7. A method of making an optical element by forming a polymer layer
employing a thermally initiated cationic ring opening
polymerization reaction which comprises: a. mixing one or more
monomers, a latent thermal cationic acid generator and a cationic
photoinitiator; b. forming a layer of the mixture of (a); c.
heating the layer to partially cure it; d. irradiating the layer to
form a variable index of refraction profile in the layer; and e.
heating the layer to fully cure all of the unreacted monomers.
8. The method of claim 7 wherein the monomer is an epoxy, an
oxetane or mixtures thereof.
9. The method of claim 7 wherein the photoinitiator is an
arylsulfonium, alkylsulfonium, or aryliodonium photo acid
generator.
10. The method of claim 7 wherein the thermal initiator is a latent
thermal cationic acid generator.
11. The method of claim 10 wherein the latent thermal cationic acid
generator is ammonium hexafluoroantimonate.
12. A method of making an optical element having a variable index
of refraction profile which comprises: a. forming a layer
comprising a mixture of two or more monomers that have differing
initial refractive indices and differing cured refractive indices;
and b. curing specific monomers at specific points across the layer
to create a pattern of refractive index that has a .DELTA.n of up
to 0.30.
13. The method of claim 12 wherein two or more of the following
monomers are present in said mixture of (a): R(SH).sub.n R(X).sub.n
and R(Y).sub.n
14. A method of making a lens material comprising: a. making a mold
of a desired shape, b. melting a mixture of monomers selected from
the group consisting of R(SH).sub.n, R(X).sub.n and R(Y).sub.n and
c. curing the monomers with heat
15. The method of claim 14 wherein the lens material is a slab
(sheet).
16. The method of claim 14 wherein the lens material is a lens
blank.
17. A formulation to make an optical element which comprises: a.
one or more monomers selected from the group consisting of epoxy
monomers, oxetane monomers and mixtures thereof and b. a thermal
initiator.
18. The formulation of claim 17 further comprising a
photoinitiator.
19. The formulation of claim 18 wherein the thermal initiator is a
latent thermal cationic acid generator and the photoinitiator is an
arylsulfonium, alkylsulfonium, or aryliodonium photo acid
generator.
20. The formulation of claim 19 wherein the latent thermal cationic
acid generator is ammonium hexafluoroantimonate.
Description
[0001] The present application claims the benefit of U.S.
Provisional application Ser. No. 60/784,394 filed 20 Mar. 2006
which is incorporated herein by reference.
RELATED ART
[0002] U.S. Pat. No. 6,989,938 (the '938 patent) and U.S. Pat. No.
6,813,082, each to Bruns, describe wavefront aberrators and methods
for manufacturing the same. The '938 patent describes how a unique
refractive index profile can be created in a monomer layer by
controlling the extent of curing of the monomer in different
regions across the surface, thus creating a wavefront aberrator.
The '938 patent further describes a method that allows one to
achieve a unique refractive index profile through the creation of
regions with varying degrees of cure. Additionally, the PCT
application with the Publication Number WO 2006/029264 describes in
more detail materials that may be used to correct high order
aberrations.
[0003] Wavefront aberrators that correct for both low order and
high order aberrations are known. These aberrators contain a
polymer layer wherein the polymer layer can be programmed by curing
to have a variable index of refraction profile or a constant index
of refraction throughout the aberrator. See for example the
following U.S. Pat. Nos. 6,813,082; 6,989,938; 6,712,466;
6,840,619; 6,942,339 and 7,021,764 all of which are incorporated
herein by reference.
[0004] Co-pending U.S. application Ser. No. 10/936,030 Document No.
2006/0052547 discloses monomer and polymers useful in making
optical elements and is incorporated herein by reference in its
entirety.
SUMMARY
[0005] A preferred embodiment provides a composition to form an
optical element or lens material that may comprise: a matrix
polymer having a monomer mixture dispersed therein, the matrix
polymer being selected from the group consisting of epoxy monomers,
oxetane monomers, and mixture of epoxy and oxetane monomers.
Another preferred embodiment provides a method for making such a
composition and said optical element. The method may comprise
intermixing, in any order, the matrix monomers, latent thermal
cationic acid generator for cationic ring opening polymerization of
epoxy and oxetane functional groups, and/or cationic
photoinitiators chosen from aryl and alkyl sulfonium and iodonium
photo acid generators. The monomers can be cured partially or fully
with heat. If cured partially, the addition of a photoinitiator
will allow the optical element to be programmed with a variable
index of refraction profile and/or etched with a logo by exposure
to light (UV, laser, etc). After the programming or logo etching
(writing) the composition is heated further to cure substantially
all of the remaining unreacted monomers.
[0006] Another preferred embodiment provides a composition that may
comprise: polyepoxy and/or polyepisulphide and/or polyisocyanate
along with at least one polythiol compound and olefin-terminated
monomer as individual components (or mixed as commercially
available Norland Optical Adhesive) in the presence of amine
catalyst and photoinitiator.
[0007] Other preferred embodiment provide a method for making a
programmable lens. The method may comprise using a very well
degassed formulation in between two CR-39 sheets separated with the
spacer, thermal cure the assembly for suitable time at accommodated
temperature, grind the assembly to be fit in the desired frame,
write the desire power and flood it, heat it to delaminate the two
CR-39 sheets, secure the final designed lens in the frame.
[0008] Additional preferred embodiments provide a composition
comprising: polyepoxy and/or polyepisulphide and/or polyisocyanate
along with at least one polythiol compound in the presence of amine
catalyst.
[0009] Another preferred embodiment provides a method for making a
lens blank. The method comprises using: two CR-39, polycarbonate,
or 1.6 lens blanks grinded to the required geometry and one of them
has two holes close to the edges allow to inject and to get rid of
bubbles; glued rings placed over each other to make the desired
thickness to be used as a spacer between the two lens blanks in
order to make mold-shape design; aluminum tape to be wrapped around
the mold to keep the mold from any geometrical change; and a mix of
polyfunctional monomers selected from the group consisting of
sandwiched between the first and second lenses selected from the
group consisting of polyepoxy and/or polyepisulphide and/or
polyisocyanate along with at least one polythiol compound in the
presence of amine catalyst.
[0010] A preferred embodiment provides a composition comprising:
polyepoxy and/or polyepisulphide along with at least one polythiol
compound and olefin-terminated monomer in the presence of amine
catalyst, photoinitiator, and stabilizer.
[0011] Another preferred embodiment provides a method for making
such spectacle lens. The method may comprise using a very well
homogenized and degassed formulation injected between two lens
blanks (base and cap) separated with a 500 .mu.m photocurable
spacer, thermal cure the assembly for suitable time at accommodated
temperature, grind and polishing the assembly to be 0.5+0.5+0.8 mm
for cap, gel, and base, respectively. Write the desire power
followed by flood curing it, add the hard and anti-refraction
coats, grind it to the final shape that fit with the required
frame, and frame it.
[0012] Also described herein is a polymerizable composition for
making a spectacle lens. A high order aberration correction may be
written on this lens. The compositions may comprise polyepoxy,
polyepisulfide and/or isocyanate along with at least one polythiol
compound and olefin-terminated monomer in the presence of amine
catalyst and photoinitiator as well as stabilizer. The composition
may comprise 60% of Ene+Thiol and 40% of Epoxy+Thiol. The gel may
be soft, provide a .DELTA.n of 0.019, and provide fast diffusion of
free monomers.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0013] The term "Spectacle Lens" is used herein in its usual sense
and includes, e.g., a polymerizable formulation built up by mixing
multifunctional smaller molecules of monomeric materials together,
pre-polymers, oligomers, crosslinked polymers, blends, and
interpenetrating polymer networks.
[0014] A compound represented by general formulas (1) used in this
invention is characterized in having mercapto groups:
R SH).sub.n (1)
[0015] Wherein when n is 3, R is an organic residue:
##STR00001##
[0016] When n is 4, R is an organic residue:
##STR00002##
[0017] A compound represented by general formulas (2) used in this
invention is characterized in having epoxy, episulfide and/or
isocyanate groups:
R X).sub.n (2)
For epoxy,
##STR00003##
[0018] Wherein when n is 2, R is an organic residue:
##STR00004##
or/and
[0019] Wherein when n is 3, R is an organic residue:
##STR00005##
Wherein when n is 3.6, R is an organic residue:
##STR00006##
For polyisocyanate,
X.dbd.*--NCO
Wherein when n is 2, R is an organic residue:
##STR00007##
For polyepisulfide,
##STR00008##
Wherein when n is 3, R is an organic residue:
##STR00009##
Wherein when n is 3.6, R is an organic residue:
##STR00010##
[0020] A compound represented by general formulas (3) used in this
invention is characterized in having Ene (allyloxy or acrylate)
groups:
R Y).sub.n (3)
For allyl-terminated Ene,
##STR00011##
Wherein when 11 is 2, R is an organic residue
##STR00012##
Wherein when n is 3, R is an organic residue
##STR00013##
[0021] A catalytic amount of amine is chosen from the group
included, but not limited to, tetrabutylaminobromide,
dimethylbenzyl amine, triethylamine, or propylamine.
[0022] The following examples illustrate the practice of the
present invention but should not be construed as limiting its
scope.
[0023] In the following examples physical properties for an example
formulation and resin prepared were evaluated as following: (1) A
refractive index (n.sub.D) measured at 25.degree. C. using a
digital Reichert Mark II Plus refractometer. (2) The viscosity was
measured at 25.degree. C. using a digital Brookfield DV-II+
viscometer. (3) The adhesion strength of polymerized film between
two bonded/glued lens blanks was measured at room temperature using
DeFelsco Percision Adhesion Tester. (4) The formulations were
made/mixed at 70.+-.5.degree. C. using Bushi Rotavapor R-114. (5)
Impact resistance: According to USA FDA standards, a falling ball
test was conducting by dropping steel balls (11 g, 16.33 g and
66.75 g) on a lens with a center thickness of 4.0 mm from the
height of 120 cm. The results were rated with one of three grades;
A: no change, B: star crack and C: steel ball penetration.
EXAMPLE 1
[0024] Materials: Starting materials were either commercially
available or synthesized. Trimethylolpropane
tris(3-mercaptopropionate), pentaerythritol
tetrakis(2-mercaptoacetate) and pentaerythritol
tetrakis(3-mercaptopropionate), tetrabutylammonium bromide (TBABr),
dimethylbenzyl amine (DMBA), bis[4-(glycidyloxy)phenyl]metane
(bisphenol F diglycidyl ether), bisphenol A diglycidyl ether,
di(ethylene glycol) bis(allyl carbonate) (CR 39), benzophenone,
triallyl triazine trione and triallyloxy triazine, were purchased
from Aldrich. 4-Mercaptomethyl-3,6-dithia-1,8-octanedithiol (MDO)
was synthesized using well know synthetic techniques.
Poly[(phenylglycidyl ether)-co-formaldehyde] (Epoxy Novolac Resin,
D.E.N. 438) was purchased from The Dow Chemical Company. Araldite
RD-2 (butanediol diglycidyl ether) was purchased from Huntsman.
1,1,1-Tris(p-hydroxyphenyl)ethane triglycidyl ether THPE/GE was
purchased from Chemist Electronic Materials L.P. Diallyl maleate
(DIAM), triallyl trimellitate (TATM) and diallylether Bisphenol A
were purchased from BiMax. 1-Hydroxy-cyclohexyl-phenyl-ketone
(Irgacure 184) was purchased from Ciba.
N-nitrosophenylhydroxylamine aluminium salt (N-PAL) was purchased
from Albemarle Corp.
[0025] "5.3486 g of D.E.N. 438, 2.6433 g of Diallylether Bisphenol
A, 6.8139 g of Trimethylolpropane tris(3-mercaptopropionate),
0.0148 g of Irgacure 184, 0.1485 g of Tetrabutylammonium bromide,
and 0.003 g of N-PAL were weighed, added to a clean vial and mixed
with a magnetic stirrer @ 70.degree. C. (water bath) for 10 min and
named as Part I.
[0026] In another clean vial were added 5.9456 g of
Trimethylolpropane tris(3-mercaptopropionate), 2.4001 g of
Diallylether Bisphenol A, 4.0001 g of Di(ethylene glycol) bis(allyl
carbonate), 0.0026 g of N-PAL, and 0.0191 g of Benzophenone and
mixed with a magnetic stirrer @ 70.degree. C. (water bath) for 10
min and named as Part II.
[0027] Part I and Part II were mixed well and degassed to from a
monomer/polymer mixture. Two 1.6 index lens blanks (base & cap)
were glued to each other through a UV curable glue containing
polystyrene beads with 500 .mu.m (micron) diameter. The glue with
beads was dispensed close to the edge of the cap and then pressed
onto the base and photocured to give a space of 500 .mu.m between
the base and cap for injecting the monomer/polymer mixture into it
to form a lens assembly. The lens assembly was transferred into an
oven with well controlled temperature and it was heated for 5-8 hr
@75.degree. C. to partially cure the monomer/polymer mixture. The
lens assembly was then grinded and polished to the desired
thickness. It was transferred to Lens Writer lab to write (etch) a
logo with a laser light. The lens assembly was then flood cured
with UV light to cure the remaining monomers. The spectacle lens
was grinded, polished and placed in an eyeglass frame.
Lens Blank
[0028] Also described herein are polymerizable compositions for
lens blanks with high refractive index comprising polyepoxy and/or
polyepisulfide and/or polyisocyanate along with at least one
polythiol compound in the presence of amine catalyst.
[0029] The term "Lens Blank" is used herein in its usual sense and
includes, e.g., a polymerizable formulation built up by mixing
multifunctional smaller molecules of monomeric materials together,
pre-polymers, oligomers, crosslinked polymers, blends, and
interpenetrating polymer networks.
[0030] A catalytic amount of amine is chosen from the group
included, but not limited to, tetrabutylaminobromide,
triethylamine, or propylamine.
EXAMPLE 2
Lens Blank
[0031] Starting materials described in Example 1 were also employed
in this example. Additionally, CR-39 lens blanks grinded to the
required geometry were purchased from Vision-Ease, Indonesia. Glued
rings of tape were used as an assembly spacer--product
#100-00089-01 from Cellotape. Irganox 1010 was purchased from from
Ciba.
[0032] Epoxy D.E.N. 438 heated in an oven at a temperature of
75.degree. C. to melt the material. In a clean 500 mL capacity
flat-bottom flask was placed 28.7 g of Epoxy D.E.N. 438, 34.2 g of
Trimethylolpropane tris(3-mercaptopropionate) and 0.063 g of TBABr.
Hock the flask to the rotary evaporator and immersed it into a
water bath at a temperature of 60.+-.5.degree. C. The flask was
allowed to rotate at the maximum speed of the rotavapor for 45-60
min or until an homogeneous and clear mixture is formed. The flask
was removed from the rotavapor and the hot viscous mixture was
poured into a clean 300 mL glass beaker. The refractive index of a
cured layer of the mixture was measured immediately. A layer of the
mixture was made using 2 slides separated by 10 mil wire spacers.
The mixture layer was then cured before taking the refractive index
measurement. The beaker with the mixture was placed into a
desiccator and a vacuum was applied until all bubbles were gone.
The vacuum was broken down slowly with dry Argon gas. The processes
of the previous two sentences were repeated three times.
[0033] Glued rings were placed over each other to make a desired
thickness gasket to be used as a spacer between the two lens blanks
to make a sandwich lens configuration. Two CR-39 lens blanks were
grinded to the required geometry. In one of those CR-39 lens
blanks, two small holes were drilled at two edges of the lens
opposite each other. These holes were made to allow easy injection
of the monomer/polymer formulation mixture and removal of air and
bubbles from the formulation. The other CR-39 lens blank was left
as it is. The two grinded CR-39 lens blanks were placed together in
a mold-shape using the spacer made of the glued rings at the edges.
Aluminum tape was placed around the mold to secure the formulation
liquid inside the mold. The formulation was slowly injected through
one of the two holes made in the CR-39 lens blank until the whole
space inside the mold was filled and the air bubbles were removed
through the other hole. The mold with the formulation was allowed
to stand horizontally for 10-15 min.
[0034] The mold was transferred with the material into the
desiccator and a vacuum was applied until no bubbles were visible
in the mold. The vacuum was slowly broken down with dry Argon. The
processes described in the previous two sentences was repeated
three times. The degassed mold along with the two slides were
carefully transferred into the oven and were heated for 5-6 hr at
75-80.degree. C. The temperature of the oven was raised to
100.degree. C. and continued to heat the mold for 2 more hours and
then one more hour at 120.degree. C. The oven was allowed to cool
down and then the mold and microscope slides were taken out. The
aluminum tape around the molds was removed. The mold assembly was
transferred to the lens machine shop to be grinded to the desired
geometry. Refractive index and the UV transmittance of cured
materials were measured.
Slab/Lens
[0035] Also disclosed herein are polymerizable compositions for
making a spectacle lens with high refractive index. In some
variations the lens may be written on in a short time. The
compositions may comprise polyepoxy and/or polyepisulfide and/or
polyisocyanate along with at least one polythiol compound and
olefin-terminated monomer in the presence of amine catalyst and
photoinitiator. The compositions may comprise Norland adhesive,
provides fast curing and provides slow diffusion of free
monomers.
[0036] A catalytic amount of amine is chosen from the group
included, but not limited to, tetrabutylaminobromide,
Dimethylbenzyl amine, triethylamine, or propylamine.
EXAMPLE 3
Slab/Lens
[0037] Starting materials described in Examples 1 and 2 were also
employed in this example. Additionally, CR-39 triallyl trimellitate
was purchased from Aldrich. Norland Optical Adhesive NOA was
purchased from Norland Products Inc. CR-39 sheets were purchased
from Fasta Tek Optics Inc. Wire with 0.040'' diameter for use as a
lens assembly spacer was purchased from Small Parts, Inc. Ceramic
tape Double-Coated was purchased from 3M.
[0038] 4.9886 g of 1,1,1-Tris(p-hydroxyphenyl)ethane triglycidyl
ether (Epo #4)+4.1647 g of bis[4-(glycidyloxy)phenyl]metane
(Bisphenol F diglycidyl ether) (Epo #7)+4.0330 g of Norland Optical
Adhesive NOA-61+0.9899 g of diallyl maleate (DIAM)+7.9160 g of
pentaerythritol tetrakis(2-mercaptoacetate) (Thiol #27) were
weighed, added to a clean vial and mixed with a magnetic stirrer @
70.degree. C. (water bath) for 10 min. 0.0217 g of dimethylbenzyl
amine (DMBA) was added with a micropipette and the mixture was
stirred again. The formulation was degassed under vacuum at room
temperature resulting in a formulation mixture.
[0039] A mold of 3''.times.2''.times.1 mm dimensions was made using
two transparent CR-39 sheets, a wire spacer with a 0.04''
thickness, and ceramic double-coated tape. The degassed formulation
mixture was injected into the mold while it was in vertical
orientation to get rid of the bubbles. The whole assembly was
degassed, transferred into a cleaned and well temperature
controlled oven, and baked at the temperature of 75.degree. C. for
4-5 hr whereupon the formulation mixture turned into a gel
material. The mold with the gelled material was then cut and
grinded to the shape of an eyeglass frame. The grinded assembly was
transferred to Lens Writer to write and flood cure it using the
appropriate UV light source. The assembly was heated to
110-120.degree. C. to delaminate the two CR-39 sheets and re-fit
the so called programmed lens in the frame. An impact resistance
test was performed by dropping two steel balls, separately,
weighing 16.33 g and 66.75 g. Each ball was dropped onto the lens
from the height of 120 cm and the result was "A" (neither change,
star crack, nor ball penetration was observed).
Thermally Initiated Cationic Ring Opening Polymerization
[0040] Also described herein are monomeric and oligomeric materials
and stabilized mixtures of monomeric and oligomeric materials
useful for making optical elements such as lenses via thermally
initiated cationic ring opening polymerization with latent thermal
cationic initiators or both independently on demand with latent
thermal and photo cationic initiators.
[0041] In one embodiment of the present invention an optical
element is made by preparing a formulation mixture that contains
epoxy monomers, oxetane monomers or mixtures of epoxy and oxetane
monomers and a thermal initiator such as a latent thermal cationic
acid generator. The formulation is then formed into a layer less
than about 5 mm thick, advantageously less than about 1 mm thick
and preferably about 0.5 mm thick. Preferably, this layer is formed
in between two ophthalmic lens blank, such as 1.6 index plastic
lens blanks. The layer is then subjected to heat to cure the
monomers present in the formulation. This thermal curing can be
complete or it can be partial. If the layer is partially cured then
radiation (UV light, laser, etc) energy can be used to further cure
the layer when a photoinitiator is also added to the formulation.
The further curing can be used to program the layer to have a
variable index of refraction in order to correct for high order
optical aberrations. Also, a logo could also be written on the
layer in an inconspicuous area that does not affect the performance
of the optical element. After the programming or logo writing is
completed the layer is then exposed to further heat to fully cure
substantially all monomers in the layer. This forms a stable
optical element.
[0042] Another preferred embodiment provides a composition that may
comprise an epoxy monomer, oxetane monomer, and epoxy-oxetane
monomer mixtures that comprises a cationic photoinitiators chosen
from aryl and alkyl sulfonium and iodonium photo acid generators in
addition to a thermal latent cationic photoacid generator. Another
preferred embodiment provides a method for making such a
composition. The method may comprise: 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 epoxy monomers, oxetane monomers, and mixture of
epoxy and oxetane monomers undergoing thermal ring opening epoxy or
oxetane or epoxy-oxetane polymerization and copolymerization.
Preferably, the polymerization of the monomer mixture comprises
thermal polymerization activated in the temperature range of 50 to
100.degree. C. Another preferred embodiment provides a method of
such epoxy or oxetane or epoxy/oxetane monomer mixtures to include
both thermal and photo acid initiators which are capable of
initiating cationic ring opening polymerization. Another preferred
embodiment involves partial cure of such epoxy, oxetane, or
epoxy/oxetane matrix containing both photo and thermal cationic
acid generators at the preferred temperature range of 60 to
75.degree. C. Another preferred embodiment involves photochemically
curing the partially cured matrix via actinic radiation at ambient
or elevated temperature to create a photo programmable matrix.
Another embodiment comprises of a selection of photo acid
generator, such as aryl and alkyl sulfonium photo acid generators,
which exhibits high thermal stability without undergoing thermal
decomposition to generate super acids under thermal cure conditions
between 60.degree. to 100.degree. C. Another preferred embodiment
involves the incorporation of thermal latent cationic initiators
chosen from Nacure.RTM. Super XC-7231, ammonium
hexafluorantimonate, and Nacure.RTM. Super A233 both from King
Industries.
[0043] Another preferred embodiment comprises dimeric, oligomeric
or polymeric epoxy and oxetane functional groups. Such epoxy
materials which result from the reaction of bisphenol-A
(4,4'-isopropylidenediphenol) and epichlorohydrin, or by the
reaction of bisphenol-A diglycidyl ether epoxies with another
bisphenol-A monomers. Preferred epoxy monomers in the present
invention involve Araldite LY-564, Araldite GY-6004, bisphenol-A
diglycidyl ether epoxy, and poly[(phenylglycidyl
ether)-co-formaldehyde] (Epoxy Novolac Resin, D.E.N. 438) from Dow
Chemicals. A reactive epoxy diluents in preferred embodiment are
from 4-vinylcyclohexene dioxide, 4-vinylcyclohexene oxide, Araldite
RD-2, Cyracure UVR-6105 (3,4-epoxycyclohexylmethyl
3,4-epoxycyclohexane-carboxylate), and Cyracure UVR-6128. Oxetane
diluents, monomers, and oligomers can be from Cyracure UVR-6000
(3-ethyl-3-(hydroxymethyl)oxetane) and OXT-121
(1,4-bis([(3-ethyl-3-oxetanylmethoxy)methyl]benzene, xylilene
oxetane, n=1-3). Cyracure UVR-6000 is the preferred oxetane in this
invention.
[0044] Another preferred embodiment comprises the addition of some
stabilizers, such as stabilizers from Ciba Chemicals under the
trade name of Irganox, well known to skilled in the art.
EXAMPLE 4
[0045] Starting materials described in the above Examples were also
employed in this example. Additionally, Araldite LY-564 was
obtained from Huntsman Chemical Company. Cyracure UVR-6000,
(3-ethyl-3-(hydroxymethyl)oxetane) and Cyracure UVR-6976 were
obtained from The Dow Chemical Company. Nacure.RTM. Super XC-7231,
ammonium antimonite was obtained from King Industries, Inc.
[0046] Araldite LY 564 had a viscosity around 1400 cP at 25.degree.
C. Araldite LY-564 was diluted with different amounts of Cyracure
UVR 6000 to get a viscosity profile. The following table is a
summary of the viscosity changes observed with respect to weight
percent of Cyracure UVR 6000 added into Araldite LY-564.
TABLE-US-00001 Amount of Cyracure .eta. (cP, 25.degree. C., 10 rpm,
UVR 6000 (wt %) spindle = 40) 15.0 560 7.5 750 4.86 920 3.96
1025
EXAMPLE 5
[0047] Araldite LY-564 was formulated with Cyracure UVR-6000 and
Nacure.RTM. Super XC-7231 to test thermal cure profiles. Cyracure
UVR 6000 was added based on the weight of Araldite LY 564. The
added amount was 3.88 wt %. Nacure.RTM. Super XC-7231 was added
based on the total weight of the formulation (0.78 wt %). The
following table shows the overall weight percentages that are
normalized to a 100% scale.
TABLE-US-00002 Component Amount (g) % wt/wt Cyracure UVR 6000
0.1166 3.69 Araldite LY 564 3.0142 95.53 Nacure .RTM. Super XC-7231
0.0245 0.78
[0048] The formulation was stirred overnight. Three sandwiched
slides from microscope slides at 500 .mu.m thickness and three
vials containing 20 drops of the formulation were prepared. Samples
were kept at 75.degree. C. in a convection oven. Refractive index
of the formulation was n.sub.D.sup.25=1.5491 and the cured film
after 5.5 hours had a refractive index of n.sub.D.sup.25=1.5709
(.DELTA.=0.022). Viscosity of the formulation was 1,078 cP at
25.degree. C. (10 rpm, 41.2% torque, spindle=40). The cured film
was hard and the slides exhibited excellent adhesion to the glass.
The cured film was clear, colorless, exhibited high transmittance
and was free from scattering. No wiggly lines (or alligator skin
lines) were observed.
EXAMPLE 6
[0049] Another formulation similar to Example 5 was prepared to
test the repeatability and the shelf life of the formulation. The
formulation details are given in the following table.
TABLE-US-00003 Component Amount (g) % wt/wt Cyracure UVR 6000
0.2332 3.70 Araldite LY 564 6.0230 95.49 Nacure .RTM. Super XC-7231
0.0512 0.81
[0050] Cyracure UVR 6000 was added based on the weight of Araldite
LY 564. The added amount was 3.87 wt %. Nacure.RTM. Super XC-7231
was added based on the total weight of the formulation (0.82 wt %).
The formulation was stirred overnight. Three sandwiched microscope
slides at 500 .mu.m thickness and three vials containing 20 drops
of the formulation were prepared. The samples were kept at
75.degree. C. in a convection oven. The refractive index of the
formulation was n.sub.D.sup.25=1.5493, z=22.9. Viscosity of the
formulation was 1096 cP at 25.degree. C. (10 rpm, 41.9% torque,
spindle=40). The cured film was hard and the slides exhibited
excellent adhesion to the glass. The cured film was clear,
colorless, free from scattering and exhibited high transmittance.
No wiggly lines (or alligator skin lines) were observed. Adhesion
to glass was excellent after 5.5 h of curing at 75.degree. C.
[0051] The viscosity and the refractive index of the formulation
were measured after 6 days later and did not exhibit any change
(.eta.=1015 cP, 38.8% torque, 10 rpm, spindle=40,
n.sub.D.sup.25=1.5493, z=22.9). Further samples were taken and
examined over a 3 month period. Viscosity and refractive index
measurements yielded no significant changes. It proved that the
initiator is a latent thermal initiator for cationic ring opening
polymerization, CROP, and the formulation was stable at ambient
temperatures.
EXAMPLE 7
[0052] The formulation with Araldite LY 564, Cyracure UVR 6000, and
Nacure.RTM. Super XC-7231 was prepared to test mid-range
scalability (see ratio of components in the table below). A scaled
up formulation was also used to get enough material for pull tests,
shrinkage measurements, shelf life stability and spectacle lens
assembly in sandwiched format from 1.6 index lens materials.
Details of the formulation were tabulated in the table below. All
ingredients were carefully weighed into a pre-washed 250 mL
round-bottom flask that was equipped with a magnetic stirrer. The
formulation contents were mixed by stirring for 20 h. The
formulation was filtered through a Stericup filter (0.45 .mu.m)
under vacuum. The clear formulation was poured into pre-washed,
dry, and argon purged amber bottles. The yield was 60.15 g
(85.06%). The loss in the flask during transfer to the Stericup
filter was 1.69 g (2.39%). The remaining mechanical loss occurred
during filtration and in the Stericup filter. Four sandwiched
microscope slides at 500 .mu.m thickness were prepared and cured at
75.degree. C. for 17 h. The adhesion to the glass substrate was
excellent. It was impossible to release the cured film from the
sandwiched configuration. Open face samples were prepared and cured
at 75.degree. C. for 17 h. Even the open faced films adhered to
glass substrate very well. Meticulous measurements of refractive
index were taken from the film. Some results were repeated by using
a high index contact fluid. The film index measured at 25.degree.
C. was 1.5794. Viscosity and physical data are summarized in the
following two tables. Adhesion to the glass substrates and 1.6 lens
blanks was excellent.
TABLE-US-00004 Component Amount (g) % wt/wt Cyracure UVR 6000 2.62
3.71 Araldite LY 564 67.49 95.43 7Nacure .RTM. Super XC-7231 0.61
0.86 Total 70.72 Viscosity (cP, 25.degree. C., Spindle = 40) %
Torque rpm n.sub.D.sup.25 1088 20.8 5 1.5492, z = 22.9 1096 41.9 10
1.5794 (Film) 1112 85.0 20 .DELTA.n = 0.030
EXAMPLE 8
[0053] The formulation of example 7 passed the pull tests (adhesion
>1200 psi) after 5.5 h and 18 h of curing. Adhesive and chunks
failed during the pull tests but the formulation material did not
show any sign of delamination from 1.6 lens material or failure of
any kind. The total shrinkage was determined to be 3.0% (1.0%
linear in each direction). It might be necessary to repeat the
experiments with a larger mass samples to get more accurate picture
of shrinkage. The liquid density was measured as 1.1480 g/mL at
23.degree. C.
EXAMPLE 9
[0054] Lens assemblies were formed from 1.6 index materials by
sandwiching the formulation of Example 7 between two 1.6 index lens
blanks set at 0.5 mm. The formulation was filled in to get a 0.5 mm
thickness layer between the 2 lens blanks and it was cured at
75.degree. C. for 17 h. The lenses were used in Example 8 for
adhesion tests. Later, they were cut into half after the pull tests
to determine the cap, film, and base thicknesses. In each case the
film thickness was around 0.50 mm.
TABLE-US-00005 Layer Thicknesses Lens # Cap Film Base 9425 0.95
0.54 7.27 9515 0.95 0.50 7.85 9258 0.88 0.57 7.79
EXAMPLE 10
[0055] The formulation with Araldite LY 564, Cyracure UVR 6000, and
Nacure.RTM. Super XC-7231 was scaled up to 700 g. Details of the
formulation are tabulated in the table below. All ingredients were
carefully weighed into a pre-washed 2 L round-bottom flask that was
equipped with a magnetic stirrer. The formulation contents were
mixed by stirring for 3 days at ambient temperature. The
formulation was filtered through Stericup filter (0.45 .mu.m) under
vacuum to a one-liter amber bottle. The clear formulation was
poured into pre-washed, dry, and argon purged amber bottles. The
yield was 696.68 g (96.85%). The overall mechanical loss occurred
during filtration and transfer was 3.15%. The formulation was
repeatable and the shelf life was greater than 3 months under
ambient conditions.
TABLE-US-00006 Component Amount (g) % wt/wt Cyracure UVR 6000 26.64
3.71 Araldite LY 564 686.52 95.43 Nacure .RTM. Super XC-7231 6.20
0.86 Total 719.36 Viscosity (cP, 25.degree. C., Spindle = 40) %
Torque rpm n.sub.D.sup.25 1020 19.5 5 1.5497, z = 22.9 1036 39.6 10
1045 79.9 20
EXAMPLE 11
[0056] Another formulation was prepared similar to the above
examples. Compositions are given in the table below. Prescription
lenses from the formulations were prepared in sandwiched format at
0.5 mm thickness between 1.6 index lens blanks. The lenses were
thermally cured for 17 h and grinded. The lenses were coated with
an anti-reflective coating and a hard coat. Finally, the lenses
were framed.
TABLE-US-00007 Component Amount (g) % wt/wt Cyracure UVR 6000 5.56
3.71 Araldite LY 564 143.15 95.43 Nacure .RTM. Super XC-7231 1.29
0.86 Total 150.00 Viscosity (cP, 25.degree. C., Spindle = 40) %
Torque rpm n.sub.D.sup.25 1110 21.2 5 1.5494 1120 42.9 10 1135 86.8
20
EXAMPLE 12
[0057] The formulation from Example 11 was reformulated by taking
10.00 g aliquots. Sulfonium based, Cyracure UVR-6976, a cationic
photo initiator was added in amounts of 0.25 and 0.5 wt % to each
10.00 g aliquot, respectively. Sample slides by sandwiching 0.5 mm
thick liquid between 3M ceramic tapes were constructed from
microscope slides. Slides were thermally cured at 75.degree. C. for
0, 1, 2, 3, 4, 5, 6, and 17 h. A logo was attempted to be written
photochemically on the cured slides with a spatially filtered
tripled YAG laser operating at 25 kHz with 8 nanoseconds pulses
with an average power of 23 mW at 355 nm. Three laser passes were
carried on to write the logo. The slides were then examined. Logo
writing was successful on all slides except the 17 h cured slide.
It was clear form the experiments that 17 h cure did not leave any
residual monomers to provide enough dynamic range for logo writing.
The polymerization was mostly carried out via thermal latent acid
initiator. Sulfonium photo acid generators were stable under the
experimental conditions and they did not release acid. Separate
control experiments with only Araldite LY-564/Cyracure UVR-6000 and
Araldite LY-564/Cyracure UVR-6000/Cyracure UVR-6976 were prepared
and kept at 75.degree. C. for 17 h. There was no apparent cure for
the samples. The slides were put in the oven at 75.degree. C. for
additional 2 h to diffuse the remaining monomers and slides were
further examined. Logo image was enhanced on the slides except for
the 0 h cured slide which showed some image washing. Further,
slides were kept in the oven for additional 15-16 h except for the
17 h cured slide. The logo image fainted but was still visible in
all slides except 0 h cured slide. The best results were taken from
the samples having 0.5 wt % photoacid generator and an initial cure
time of about 4 to 6 h. Six hour cure was the preferred time for
logo writing.
[0058] Five more slides were prepared and thermally cured at
75.degree. C. for 6 h. Logo writing was attempted after 3 days and
7 days. A logo was successfully written after 3 and 7 days
indicating that activating the thermal cationic initiator for 6 h
at 75.degree. C. did not completely consume the available dynamic
range for the logo writing. The written logo showed enhanced
characteristics after two additional hours at 75.degree. C. Keeping
the slides at 75.degree. C. for an additional 17 h did show some
fading but the quality was still excellent and logo was visible.
The number of logo writing passes is not limited to three passes
and can be modified in any number to adjust desired image writing
and post image fixing properties.
* * * * *