COMPOSITION FOR THE MANUFACTURE OF AN OPHTALMIC LENS COMPRISING SEMI-CONDUCTIVE NANOPARTICLES

Abstract

A polymerizable liquid composition including semi-conductive nanoparticles for the manufacture of ophthalmic lenses. Specifically, polymerizable composition has at least one monomer or oligomer; at least one catalyst for initiating the polymerization of the monomer or oligomer; and semi-conductive nanoparticles, which are dispersed in the monomer or oligomer. The absorbance through a 2-millimeter-thick layer of the polymerizable composition is higher than 0.5 for each light wavelength ranging from 350 to λ.sub.cut, λ.sub.cut being in the visible range, preferably in the range from 400 nm to 480 nm.

Claims

1.-14. (canceled)

15. A polymerizable composition for the manufacture of an ophthalmic lens, comprising: (a) at least one monomer or oligomer; (b) at least one catalyst for initiating the polymerization of said monomer or oligomer; and (c) semi-conductive nanoparticles which are dispersed in said monomer or oligomer, wherein the absorbance through a 2-millimeter thick layer of said polymerizable composition is higher than 0.5 for each light wavelength ranging from 350 to λ.sub.cut, λ.sub.cut being in the visible range.

16. The polymerizable composition according to claim 15, wherein λ.sub.cut is in the range from 400 nm to 480 nm.

17. The polymerizable composition according to claim 15, wherein monomer is an allyl monomer or an allyl oligomer.

18. The polymerizable composition according to claim 15, wherein the catalyst is a free radical initiator.

19. The polymerizable composition according to claim 15, wherein monomer is an alkoxysilane.

20. The polymerizable composition according to claim 18, wherein the catalyst is a Lewis acid.

21. The polymerizable composition according to claim 15, wherein the semi-conductive nanoparticles comprise a material of formula
M.sub.xQ.sub.yE.sub.zA.sub.w  (I), wherein: M is selected from the group consisting of Zn, Cd, Hg, Cu, Ag, Au, Ni, Pd, Pt, Co, Fe, Ru, Os, Mn, Tc, Re, Cr, Mo, W, V, Nd, Ta, Ti, Zr, Hf, Be, Mg, Ca, Sr, Ba, Al, Ga, In, Tl, Si, Ge, Sn, Pb, As, Sb, Bi, Sc, Y, La, Ce, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, Cs or a mixture thereof; Q is selected from the group consisting of Zn, Cd, Hg, Cu, Ag, Au, Ni, Pd, Pt, Co, Fe, Ru, Os, Mn, Tc, Re, Cr, Mo, W, V, Nd, Ta, Ti, Zr, Hf, Be, Mg, Ca, Sr, Ba, Al, Ga, In, Tl, Si, Ge, Sn, Pb, As, Sb, Bi, Sc, Y, La, Ce, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, Cs or a mixture thereof; E is selected from the group consisting of O, S, Se, Te, C, N, P, As, Sb, F, Cl, Br, I, or a mixture thereof; A is selected from the group consisting of O, S, Se, Te, C, N, P, As, Sb, F, Cl, Br, I, or a mixture thereof; and x, y, z and w are independently a decimal number from 0 to 5; x, y, z and w are not simultaneously equal to 0; x and y are not simultaneously equal to 0; z and w may not be simultaneously equal to 0.

22. The polymerizable composition according to claim 15, wherein the semi-conductive nanoparticles are nanospheres, nanoplates or nanorods.

23. The polymerizable composition according to claim 15, wherein the semi-conductive nanoparticles are core/shell particles or core/crown particles, the core being a different material from the shell or crown.

24. The polymerizable composition according to claim 15, wherein the amount of semi-conductive nanoparticles in the composition is from 10 ppm to wt %, based on the weight of the polymerizable liquid composition.

25. The polymerizable composition according to claim 15, wherein the semi-conductive nanoparticles are capped with an organic layer or encapsulated in an inorganic matrix.

26. A process for the preparation of the polymerizable composition as defined in claim 15, comprising the steps of: (a) providing a monomer or oligomer; (b) providing semi-conductive nanoparticles in the form of a powder dispersible within said monomer or oligomer or in the form of a dispersion of said semi-conductive nanoparticles in a liquid dispersible within said monomer or oligomer; (c) providing a catalyst for initiating the polymerization of said monomer or oligomer; and (d) mixing said monomer or oligomer, said semi-conductive nanoparticles and said catalyst.

27. An ophthalmic lens obtained by curing the polymerizable composition as defined in claim 15.

28. An ophthalmic lens comprising: (a) an optical substrate; and (b) a coating obtained by curing the polymerizable composition as defined in claim 15 on said optical substrate.

29. An ophthalmic lens according to claim 28, wherein the absorbance through a 2-millimeter thick ophthalmic lens is higher than 0.5 for each light wavelength ranging from 350 to λ.sub.cut, λ.sub.cut being in the visible range.

30. The ophthalmic lens according to claim 29, wherein λ.sub.cut is in the range from 400 nm to 480 nm.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0159] FIG. 1 shows the generic absorbance of a polymerizable composition or material comprising semi conductive nanoparticles (logarithm scale) as a function of wavelength of light from 350 nm to 780 nm (linear scale): A(λ) and the principle of determination of λ.sub.cut.

[0160] FIG. 2 is a schematic representation of various shapes (spheres and plates) and structure (homostructure, core/shell, core/crown, dot in plate) of semi-conductive nanoparticles.

[0161] FIG. 3 shows absorbance curves of dispersions of semi-conductive nanoparticles capped with organic compounds.

[0162] FIG. 4 shows absorbance curves of dispersions of semi-conductive nanoparticles capped with polymeric compounds.

[0163] FIG. 5 shows absorbance curves of lenses comprising semi-conductive nanoparticles.

[0164] FIG. 6 shows absorbance curves of lens comprising a Sol-Gel coating comprising semi-conductive nanoparticles.

[0165] FIG. 7 shows the absorbance curves of CdS nanoplates in heptane (semi-dotted line), of CdS-MPA nanoparticles in water (dotted line) and of lens comprising Diethylene glycol bis(allyl carbonate) and CdS nanoplates (solid line).

[0166] FIG. 8.1 shows the absorbance curves of ZnSe nanospheres in toluene (semi-dotted line), of encapsulated ZnSe nanospheres in methanol (dotted line) and of lens comprising a Sol-Gel coating comprising ZnSe nanospheres (solid line).

[0167] FIG. 8.2 shows the absorbance curves of ZnSe nanoplates in toluene (semi-dotted line), of encapsulated ZnSe nanoplates in methanol (dotted line) and of lens comprising a Sol-Gel coating comprising ZnSe nanoplates (solid line).

EXAMPLES

[0168] The present invention is further illustrated by the following examples.

Example 1: Semi-Conductive Nanoparticles

[0169] Dot in plate semi-conductive nanoparticles (hereafter DiP) of formula CdSe.sub.xSi.sub.1-x, with x=0.3, comprising a CdSe.sub.0.5S.sub.0.5 dot included in a nanoplate of CdS in which composition varies continuously from core to shell, having a thickness of 1.2 nm (corresponding to 4 monolayers), length of 15 nm and width of 20 nm were prepared according to procedure disclosed in European Patent EP2633102. A dispersion of DiP in heptane is obtained, referred to as dispersion D0.

[0170] Table 2 below discloses the absorbance of dispersion D0.

TABLE-US-00002 TABLE 2 λ.sub.max 422 nm λ.sub.0.9 (at 0.9 * A.sub.max) 427 nm λ.sub.0.5 (0.5 * A.sub.max) 434 nm λ.sub.0.1 (0.1 * A.sub.max) 446 nm |λ.sub.0.5 − λ.sub.0.9|  7 nm |λ.sub.0.1 − λ.sub.0.9|  19 nm

[0171] 20 mL of a dispersion comprising DiP in heptane was heated in a round-bottom flask at 65° C. and 0.5 mL of 1-octanethiol was carefully added. The dispersion was kept at 65° C. for 3 hours. As thiols have strong affinity with Cadmium, 1-octanethiol forms an organic capping layer around DiP. The dispersion is then washed three times with absolute ethanol and heptane to remove any excess of capping compounds which may be present in the dispersion. In the end, this procedure allows the preparation a DiP dispersed in heptane, having only 1-octanethiol molecules as capping compounds. The dispersion is referred to as D8.

[0172] This procedure was repeated with 1-butanethiol instead of 1-octanethiol, yielding dispersion D4.

[0173] This procedure was repeated with 1-dodecanethiol instead of 1-octanethiol, yielding dispersion D12.

[0174] Another capping was also performed. A dispersion comprising 20 mL DiP in heptane was added in a round-bottom flask. 5 mL of absolute ethanol was added in order to precipitate all nanoplates. After solvent removal, these nanoplates were dispersed in 20 mL of toluene. 6 mL of a 0.1 M solution of cadmium bromide in toluene was then added. As Bromine anions have a strong affinity with Cadmium, they form a layer around DiP. This mixture was heated at 65° C. for 30 minutes and then washed three times with absolute ethanol and toluene, yielding a dispersion DBr.

[0175] Absorbance curves of 50 ppm of DiP in heptane were measured as a function of light wavelength in the UV-visible range before (dispersion D0) and after capping for dispersions D4, D8 and D12. Absorbance curves are displayed on FIG. 3.1: D0 solid black line, D4 dotted black line, D8 solid grey line, D12 dotted grey line.

[0176] Absorbance curve of 50 ppm of DiP in toluene was measured as a function of light wavelength in the UV-visible range before and after capping for dispersions DBr. Absorbance curve of dispersion DBr is displayed as dotted line on FIG. 3.2, with absorbance curve of dispersion D0 in solid line.

[0177] Wavelength of transition λ.sub.cut was determined for all absorbance curves and reported in Table 3. One can observe that organic layers on semi-conductive nanoparticles induce a significant shift in λ.sub.cut. This is especially interesting to design semi-conductive nanoparticles with a pre-determined wavelength of transition.

TABLE-US-00003 TABLE 3 Dispersion λ.sub.cut (nm) D0 409 D4 440 D8 440 D12 436 DBr 426

Example 2: Polymerizable Composition

[0178] Dot in plate semi-conductive nanoparticles (hereafter DiP) of formula CdSe.sub.xS.sub.1-x, with x=0.3, comprising a CdSe.sub.0.5S.sub.0.5 dot included in a nanoplate of CdS in which composition varies continuously from core to shell, having a thickness of 1.2 nm (corresponding to 4 monolayers), length of 15 nm and width of 20 nm were prepared according to procedure disclosed in European Patent EP2633102.

[0179] 0.5 mL of a dispersion comprising DiP in 10 mM NaHCO.sub.3 solution was mixed with 5 mg of a copolymer (DPn of 15-20) comprising 20 mol % of (5, 7-dimercapto)-N-(3-methacrylamidopropyl)heptanamide and 80 mol % poly(ethylene glycol) methyl ether methacrylate (Mn of 40) and kept under gentle stirring overnight at 60° C. Then sample was washed with ethanol and nanoparticles capped with polymer in ethanol was obtained. This dispersion A has a weight content in nanoparticles of 5%.

[0180] Absorbance curves of nanoparticles in ethanol were measured as a function of light wavelength in the UV-visible range before (dotted line) and after capping with polymer (solid line) and are shown on FIG. 4.1. Below absorbance of 0.01, composition is transparent with no attenuation effect visible by eye.

[0181] One can observe that wavelength of transition λ.sub.cut, changes slightly when nanoparticles are capped with a polymer. However, the shape of absorbance curve is not changed. Transition from a transparent dispersion to a very absorbent dispersion is very sharp: absorbance decreases from 1 to 0.2 over about 25 nm.

[0182] 70 mg of Benzoyl Peroxide (BPO, 50% weight in dicyclohexyl phthalate) was added in 2 mL of diallyl phthalate (DAP) yielding a solution B of 3 weight % of BPO catalyst in DAP monomer.

[0183] 25 μL of dispersion A and 500 μL of solution B were mixed together under vortex for 10 seconds, then sonicated in degassing mode at 25° C. for 60 seconds, yielding the polymerizable composition C1. Weight content of semi-conductive nanoparticles in composition C1 was 45 ppm.

[0184] Same experiment was reproduced with semi-conductive nanoparticles of formula CdS and having a shape of nanoplates with thickness of 0.9 nm (corresponding to 3 monolayers), length of 15 nm and width of 20 nm, yielding a polymerizable composition C2 with weight content of semi-conductive nanoparticles of 45 ppm.

[0185] Absorbance curves of nanoparticles in ethanol were measured as a function of light wavelength in the UV-visible range before (dotted line) and after capping (solid line) with polymer and are shown on FIG. 4.2.

[0186] A comparative polymerizable composition C.sub.comp was prepared without semi-conductive nanoparticles.

[0187] Same experiment was reproduced with a mixture of semi-conductive nanoparticles: 0.3 mL of composition C1 and 0.5 mL of composition C2, yielding composition C3. Such a mixture allows to adapt the absorbance curve in the region of wavelength of transition λ.sub.cut thereby providing a tool to fine tune optical performances of lenses obtained after polymerization.

Example 3: Lens

[0188] Polymerizable compositions C1, C2 and C3 were casted into moulds having centre thickness of 2 millimetres. The assembly was laid in an oven at 100° C. for 18 hours, then cooled and de-assembled, yielding respectively plastic samples S1, S2 and S3 of diameter about 2 cm.

[0189] A comparative sample S.sub.comp was prepared form polymerizable composition C.sub.comp.

[0190] FIG. 5.1, 5.2, 5.3 show absorbance of samples S1, S2 and S3 (solid lines) as a function of light wavelength in the UV-visible range. On these figures, absorbance of sample S.sub.comp (semi-dotted line) is added to highlight that absorbance of samples S.sub.n is the sum of absorbance of polymerized DAP and absorbance of semi-conductive nanoparticles.

[0191] Absorbance and wavelength of transition λ.sub.cut of semi-conductive nanoparticle used for composition C.sub.n and sample S.sub.n are almost the same, demonstrating that semi-conductive nanoparticles are not degraded during polymerization.

[0192] Besides, the characteristics of sample S1 for λ.sub.0.9, λ.sub.0.5 and λ.sub.0.1 are the same as the characteristics of dispersion of nanoparticles listed in table 2: incorporation of nanoparticles into polymerizable composition didn't change absorbance features

[0193] One can observe that absorbance is governed by semi-conductive nanoparticles in the range 380 nm-450 nm, while absorbance is governed by polymerized DAP in the range 450 nm-780 nm. Hence, decrease of the absorbance curve is less sharp on polymerized lenses due to intrinsic absorbance of polymerized DAP. If polymerized material was less absorbent, sharpness of decrease of absorbance curve would be restored.

[0194] Lenses obtained are transparent, i.e. there is no observable scattering and an object can be recognized when observed through the lens. However, these lenses absorb very efficiently high energy visible light with a very sharp transition in absorbance curve.

Example 4: Coatings

[0195] Semi-conductive nanoparticles of formula CdS and having a shape of plate with length of 20 nm; width of 40 nm and thickness of 1.5 nm (corresponding to 5 monolayers) were prepared according to procedure disclosed in EP2633102.

[0196] 1 mL of a dispersion comprising CdS nanoplates in tetrahydrofuran was added in a round-bottom flask containing 4 mL of a diluted solution of 11-Mercapto-1-undecanol at 0.02 M in tetrahydrofuran. This mixture is then heated at 50° C. under reflux for 24 hours. As thiols have strong affinity with Cadmium, 11-Mercapto-1-undecanol forms an organic capping layer around CdS nanoplates. Nanoplates were recovered by centrifugation and washed three times with heptane and methanol. A 0.5 mL methanol dispersion of CdS nanoplates capped with 11-Mercapto-1-undecanol was obtained and called dispersion Dcoat. Dispersion Dcoat had a weight content in nanoparticles of 2.5%.

[0197] In addition, a Sol-Gel solution SG was also prepared in a separated vial with 100 μL of (3-Glycidyloxypropyl)trimethoxysilane, 65 μL of diethoxydimethylsilane and 35 μL of 0.1 M HCl. Solution SG was stirred for 24 hours at room temperature.

[0198] 50 μL of dispersion Dcoat was added to 200 μL of solution SG to obtain a polymerizable composition then deposited by spin coating on a glass lens at 400 rpm during 30 s (dispensing step) then 2000 rpm during 2 min (spreading step). The resulting sample was then heated at 150° C. for 6 h in order to obtain a condensed 5 μm thick Sol-Gel coating having a weight content in CdS nanoplates of 1% after curing.

[0199] Absorbance curves of CdS nanoparticles in heptane (semi-dotted line), of CdS-mercapto-undecanol nanoparticles in methanol (dotted line) and of the coated glass lens (solid line) were measured as a function of light wavelength in the UV-visible and are shown on FIG. 6. A wavelength of transition λ.sub.cut of 445 nm is obtained for the coated glass lens.

[0200] Here again, one can observe that organic capping of nanoplates enables to change value of wavelength of transition λ.sub.cut and that wavelength of transition is not changed after curing of the coating, demonstrating that semi-conductive nanoparticles withstand polymerization conditions without being degraded.

Example 5: Lens from Polymerizable Composition Comprising Diethylene Glycol Bis(Allyl Carbonate) Monomer and CdS Nanoplates

[0201] Semi-conductive nanoparticles of formula CdS and having a shape of plate with length of 10 nm; width of 20 nm and thickness of 0.9 nm (corresponding to 3 monolayers) were prepared according to procedure disclosed in EP2633102.

[0202] 5 mL of a dispersion comprising CdS nanoplates were mixed with 2 mL of 3-mercaptoproprionic acid (MPA). This mixture was heated at 60° C. for 2 hours. Nanoplates were recovered by centrifugation and washed three times with ethanol and toluene. CdS nanoplates capped with MPA were redispersed in water at pH=10. This dispersion is called dispersion D4. Dispersion D4 had a weight content in nanoparticles of 0.5%. Nanoparticles of dispersion D4 were encapsulated according to the procedure disclosed in EP3630683 within a silica shell.

[0203] Table 4 below discloses the absorbance of dispersion D4.

TABLE-US-00004 TABLE 4 λ.sub.max 400 nm λ.sub.0.9 (at 0.9 * A.sub.max) 402 nm λ.sub.0.5 (0.5 *A.sub.max) 406 nm λ.sub.0.1 (0.1*A.sub.max) 410 nm |λ.sub.0.5 − λ.sub.0.9|  4 nm |λ.sub.0.1 − λ.sub.0.9|  8 nm

[0204] 10 mg of encapsulated CdS nanoplates of dispersion D4 were mixed with 1.65 mL of Diethylene glycol bis(allyl carbonate) and 100 mg of diisopropyl peroxydicarbonate (IPP) initiator. A homogeneous mixture is obtained by sonication in degassing mode at 25° C. for 60 seconds, yielding the polymerizable composition C4.

[0205] Polymerizable composition C4 was casted into moulds having centre thickness of 2 millimetres. The assembly was laid in an oven at 100° C. for 18 hours, then cooled and de-assembled, yielding plastic sample S4 of diameter about 2 cm.

[0206] Absorbance curves of CdS nanoplates in heptane (semi-dotted line), of CdS-MPA nanoparticles in water (dotted line) and of sample S4 (solid line) were measured as a function of light wavelength in the UV-visible and are shown on FIG. 7. A wavelength of transition λ.sub.cut of 399 nm is obtained for sample S4.

[0207] Besides, the characteristics of sample S4 for λ.sub.0.9, λ.sub.0.5 and λ.sub.0.1 are the same as the characteristics of dispersion of nanoparticles listed in table 4: incorporation of nanoparticles into polymerizable composition didn't change absorbance features

[0208] Sample S4 is a transparent lens, i.e. there is no observable scattering and an object can be recognized when observed through the lens. However, these lenses absorb very efficiently high energy visible light with a very sharp transition in absorbance curve.

Example 6: Coatings Comprising ZnSe Nanospheres and Nanoplates

[0209] Semi-conductive nanoparticles of formula ZnSe and having a shape of sphere with diameter of 5.8±0.2 nm were prepared according to procedure known in the art and reported in New J. Chem., 2007, 31, 1843-1852.

[0210] 5 mL of a dispersion comprising ZnSe nanospheres were mixed with 5 mL of 3-mercaptoproprionic acid (MPA). This mixture was heated at 60° C. for 2 hours. The nanospheres were recovered by centrifugation and washed three times with absolute ethanol and toluene. ZnSe nanospheres capped with MPA were redispersed in water at pH=10. These nanospheres were encapsulated according to the procedure disclosed in EP3630683 within a silica shell and redispersed in 0.5 mL of methanol. This dispersion was called dispersion D5 and had a weight content of 2.5% of nanospheres.

[0211] Table 5 below discloses the absorbance of dispersion D5.

TABLE-US-00005 TABLE 5 λ.sub.max 424 nm λ.sub.0.9 (at 0.9 * A.sub.max) 428 nm λ.sub.0.5 (0.5 *A.sub.max) 432 nm λ.sub.0.1 (0.1 *A.sub.max) 440 nm |λ.sub.0.5 − λ.sub.0.9|  4 nm |λ.sub.0.1 − λ.sub.0.9|  12 nm

[0212] Same experiment was reproduced with semi-conductive nanoparticles of formula ZnSe and having a shape of nanoplates with thickness of 1.9 nm (corresponding to 5 monolayers), length of 15 nm and width of 30 nm. These nanoplates were prepared according to procedure known by the man of the art and reported in Mater. Lett. 2013, 99, 172-175. ZnSe nanoplates were capped with MPA and were redispersed in water at pH=10. These nanoplates were encapsulated according to the procedure disclosed in EP3630683 within a silica shell and redispersed in 0.5 mL of methanol. This dispersion was called dispersion D6 and had a weight content of 2.5% of nanoplates.

[0213] In addition, a Sol-Gel solution SG was also prepared in a separated vial with 100 μL of (3-Glycidyloxypropyl)trimethoxysilane, 65 μL of diethoxydimethylsilane and 35 μL of 0.1 M HCl. Solution SG was stirred for 24 hours at room temperature.

[0214] 50 μL of dispersion D5 were added to 200 μL of solution SG to obtain a polymerizable composition then deposited by spin coating on a glass lens at 400 rpm during 30 s (dispensing step) then 2000 rpm during 2 min (spreading step). The resulting sample S5 was then heated at 150° C. for 6 h in order to obtain a condensed 5 μm thick Sol-Gel coating having a weight content in ZnSe nanospheres of 1% after curing.

[0215] Same experiment was reproduced with encapsulated ZnSe nanoplates. 50 μL of dispersion D6 were added to 200 μL of solution SG to obtain a polymerizable composition then deposited by spin coating on a glass lens at 400 rpm during 30 s (dispensing step) then 2000 rpm during 2 min (spreading step). The resulting sample S6 was then heated at 150° C. for 6 h in order to obtain a condensed 5 μm thick Sol-Gel coating having a weight content in ZnSe nanoplates of 1% after curing.

[0216] Absorbance curves of ZnSe nanospheres in toluene (semi-dotted line), of encapsulated ZnSe nanospheres in methanol (dotted line) and of the coated glass lens S5 (solid line) were measured as a function of light wavelength in the UV-visible and are shown on FIG. 8.1. A wavelength of transition λ.sub.cut of 410 nm is obtained for sample S5.

[0217] Besides, the characteristics of sample S5 for λ.sub.0.9, λ.sub.0.5 and λ.sub.0.1 are the same as the characteristics of dispersion of nanoparticles listed in table 5: incorporation of nanoparticles in Sol-Gel coating didn't change absorbance features

[0218] Absorbance curves of ZnSe nanoplates in toluene (semi-dotted line), of encapsulated ZnSe nanoplates in methanol (dotted line) and of the coated glass lens S6 (solid line) were measured as a function of light wavelength in the UV-visible and are shown on FIG. 8.2. A wavelength of transition λ.sub.cut of 401 nm is obtained for sample S6.