A transparent polymer material that does not contain elemental fluorine and has high oxygen diffusion.
Patent Information
- Authority / Receiving Office
- JP · JP
- Patent Type
- Applications
- Current Assignee / Owner
- ACUITY POLYMERS INC
- Filing Date
- 2024-06-17
- Publication Date
- 2026-06-30
Smart Images
Figure 2026521590000001_ABST
Abstract
Description
Technical Field
[0001] The present invention relates to a fluorine-free high gas permeability (Dk) material and a method for the same material, more specifically to a high Dk material having a Dk value exceeding 100, and even more specifically to a high Dk material suitable for use as a rigid gas permeable contact lens including a rigid gas permeable lens.
Background Art
[0002] Background of the Invention Contact lens materials are transparent materials made from highly cross-linked organic polymers. Two types of lenses are available, either soft or hard. Soft lenses are classified as silicone hydrogels made by combining a soft silicone polymer with a hydrophilic polar material. This combination of properties makes silicone hydrogels a preferred lens for comfort on the patient's eye. Unfortunately, silicone hydrogel lenses have a low oxygen permeability that can cause damage to the eye over time.
[0003] On the other hand, hard lenses are generally hydrophobic and may require surface modification to allow for good wetting in the eye. Wetting in hard lenses or rigid gas permeable (RGP) lenses is achieved by adding acids that reposition on the surface of the lens. As the name implies, RGP lenses have an increased oxygen permeability. This property that allows oxygen transport through the material is an important advantage for eye health. Unfortunately, RGP lenses incorporate fluorinated acrylates that can cause damage to the environment and may be dangerous to contact lens wearers.
[0004] Incorporating fluoroacrylates into lenses increases their mechanical properties by making them harder. At the same time, the oxygen permeability of these materials is higher than that of materials without these monomers. One of the most useful monomers is hexafluoro-i-propyl methacrylate (HFiPMA). TIFF2026521590000002.tif21128 However, fluorinated compounds have recently become targets for removal from many products due to health concerns. Numerous studies of polyfluorooctinoic acid (PFOA) and substance (PFOS) have found high levels of fluorinated substances in the blood of the general public. Acid (PFOA) is a common precursor used to prepare substance (PFOS) containing acrylate monomers.
[0005] Recent attempts to remove fluorinated monomers from contact lenses have been unsuccessful. To date, the replacement of fluorinated compounds in RGP lenses has resulted in significant degradation of properties. For example, substituting HFiPMA with methyl methacrylate (MMA) caused an 87% reduction in oxygen permeability, substituting HFiPMA with 3-methacrylateoxypropyltris(trimethylsiloxy)silane (TRIS) produced a material that was difficult to machine, and a 1 / 1 mixture of MMA and TRIS as a substitute for HFiPMA reduced oxygen permeability by about half, resulting in a significant decrease in the hardness, flexural modulus, and wettability of the resulting material.
[0006] Polyhedral oligomeric silsesquioxane (POSS) monomers are incorporated into ophthalmic materials. In one example, U.S. Patent No. 6,586,548 ('548 Patent) (Patent Document 1) teaches the polymerization of vinyl monomers for biocompatible materials in which one of the components is a POSS monomer. POSS monomers may have a single ethylenically unsaturated radical that functions as a polymerizable functional group. These materials are transparent and may be suitable for contact lenses, but these materials have low oxygen permeability and have a Dk value of about 17 to 34.
[0007] In another example, U.S. Patent No. 7,198,639 ('639 Patent) (Patent Document 2) incorporates a POSS cage into a soft lens using hydrosilation by reaction of silicon hydride with vinyl groups and a platinum catalyst. Alternatively, free radical polymerization is used to incorporate the acrylic and / or styrene groups of the POSS cage. POSS molecules functionalized with alcohol, amine, thiol, epoxy, and isocyanate groups have also been shown to be useful in the '639 Patent. POSS molecules are polyfunctional, with three functional groups arising from the vertices of the open cage. These polymer compositions can be fabricated into intraocular lens (IOL) implants, corneal inlays, and other related objects. However, since these materials were intended for implantation into the eye, the oxygen transport properties of these materials have not been reported.
[0008] In another example, U.S. Patent No. 10,633,472 ('472 Patent) (Patent Document 3) describes a method for preparing a material having high oxygen transport (high Dk). Monomers include fluoroacrylates, hydroxyalkyltris(trimethylsiloxy)silanes, hydroxyalkyl-terminated polydimethylsiloxanes, and styrylethyltris(trimethylsiloxy)silanes (styryltris). Dk values exceeding 175 have been reported, and crosslinking agents such as alkyl glycol dimethacrylate and hydrophilic agents such as methacrylic acid have also been included. The material could also be formed into rigid gas permeable (RGP) contact lenses on a lathe.
[0009] In a further example, as disclosed in publication number WO2016 / 115507 (Patent Document 4), POSS methacrylate was incorporated into poly(urethane). While the cured polymer composition was suitable for intraocular lenses and contact lenses, urethane-based acrylate copolymers were also applicable to other artificial corneas.
[0010] In the last example, U.S. Patent Application No. 2022 / 0380599 (Patent Document 5) describes a high-Dk contact lens material containing a POSS cage having at least two polymerizable groups and at least two hydrophilic groups. However, it should be noted that fluoroacrylates are incorporated into these materials. [Prior art documents] [Patent Documents]
[0011] [Patent Document 1] U.S. Patent No. 6,586,548 [Patent Document 2] U.S. Patent No. 7,198,639 [Patent Document 3] U.S. Patent No. 10,633,472 [Patent Document 4] WO2016 / 115507 [Patent Document 5] U.S. Patent Application No. 2022 / 0380599 [Overview of the Initiative]
[0012] According to aspects of the present invention, a new class of ophthalmic devices, primarily made of silicone, were formed from transparent materials that impart high oxygen permeability (Dk greater than 100). These silicone materials were molded into RGP lenses exhibiting high Dk in the absence of fluorinated comonomers. The silicone monomer replacing the fluorinated monomer is a polyhedral oligomeric silsesquioxane (POSS) cage having at least one polymerizable group and multiple organic functional groups. Furthermore, the POSS monomer having two available sites for polymerization allows for the incorporation of the silsesquioxane cage into the macromolecule backbone. Thus, the structure of the resulting polymer differs for the POSS monomer having a single polymerizable group, where the resulting silicone cage is a pendant to the polymer backbone.
[0013] In addition, POSS monomers having two or more polymerizable groups form gel-like structures. By incorporating POSS cages into the polymer backbone, the resulting polymer structure can have linearly linked silicone cages or, by incorporating other polymerizable monomers, can form linear copolymers. The POSS cages, which act as pendants to the polymer chain, can arise from the polymerization of POSS molecules having one or more polymerizable groups.
[0014] Typically, to achieve high-Dk materials with properties suitable for lens formation, it is necessary to combine fluorinated monomers with silicones. However, combining POSS silicones with organosilicon produces transparent materials with good mechanical properties. Organofunctional silicones may contain acrylates, methacrylates, styrenes, and itaconates as polymerizable groups. [Brief explanation of the drawing]
[0015] This subject matter is described herein in detail with reference to drawings provided as illustrative examples of the subject matter, so as to enable those skilled in the art to practice the subject matter. In particular, the following drawings and examples are not intended to limit the scope of this subject matter to a single embodiment, but other embodiments are possible by substituting some or all of the elements described or illustrated, and further as follows:
[0016] [Figure 1] This table shows exemplary compositions for forming non-fluorinated polymer materials according to the present invention, in which a thermal initiator is used in the polymerization reaction. [Figure 2] Figure 1 is a table showing characterization data for exemplary non-fluorinated polymer materials produced using the exemplary compositions listed. [Figure 3] Figure 1 is a plot showing the inverse transmittance versus thickness for calculating the Dk value of Comparative Example 1, as listed above. [Figure 4] Figure 1 is a plot showing the inverse transmittance versus thickness for calculating the Dk value of Example 1, as listed above. [Figure 5] A plot showing the inverse transmittance versus thickness for calculating the Dk value of Example 3 as listed in FIG. 1. [Figure 6] A table showing an exemplary composition for forming a non-fluorinated polymer material according to the present invention, in which a photoinitiator is used in the polymerization reaction. [Figure 7] A table showing the property evaluation data of an exemplary non-fluorinated polymer material produced using the exemplary composition listed in FIG. 6. [Figure 8] A plot showing the tangent (delta) of bifunctional POSS versus the weight percentage of the composition for measuring the glass transition temperature of an exemplary non-fluorinated polymer material produced using the exemplary composition listed in FIG. 6.
Mode for Carrying Out the Invention
[0017] Detailed Description The rigid gas permeable monolith is cut into a lens shape to improve the vision of people with astigmatism. The initial lenses were made from poly(methyl methacrylate). Many generations of fluoroacrylates and siloxanes have led to improved oxygen permeability and wettability. This has resulted in both better comfort for the patient and improved health inside the eye.
[0018] As described below, one aspect of the present invention is directed to biocompatible materials that replace fluorinated components with siloxanes such as POSS cages. The POSS cage has a relatively high molecular weight and has at least one, often two or more, polymerizable groups bonded to a silsesquioxane cage. The POSS cage can be accurately described as a macromer rather than a monomer. Through the judicious selection of POSS macromers, as described in more detail below, transparent materials with properties suitable for contact lenses with high oxygen permeability can be produced. Previous high Dk contact lens formulations, unlike the materials described herein, contained a high proportion of fluorinated segments.
[0019] Siloxanes used in contact lens synthesis are generally linear and branched siloxanes. Linear siloxanes include silicone polymers such as polydimethylsiloxane and typically have the molecular formula R2SiO, with two methyl groups bonded to silicon atoms and one crosslinking oxygen group for each silicon atom. They are often functionalized with polymerizable groups at one or both ends. The small molecule pentamethyldisiloxanylmethyl methacrylate (structure (I)) is a simple form of linear siloxane. TIFF2026521590000003.tif19128
[0020] The TRIS group is a branched siloxane in which a central silicon atom is bonded to one organic group, which may also contain polymerizable groups. The three groups bonded to the central silicon are composed of silicon-oxygen bonds to the other silicon atoms. The central atom of the TRIS structure is represented by the formula RSiO l.5 The initial description of the TRIS-type molecule from U.S. Patent No. 3,808,178 for Gaylord is structure (II), namely 3-[tris(trimethylsiloxy)silyl]propyl methacrylate. TIFF2026521590000004.tif42128
[0021] A third class of silicones useful in contact lenses are silicon-containing cage molecules based on the structure of oxygen and silicon tetrahedra. Silicon atoms are substantially bonded to other silicon atoms through siloxane bonds, and one of the simplest structures formed from this arrangement is generally a cube, as shown in structure (III). These silsesquioxane molecules are also this RSiO 1.5Although it fits the formula, unlike TRIS molecules, it forms a three-dimensional structure. These molecules come to be named POSS, representing polyhedral oligomeric silsesquioxane. POSS molecules can have a silica-type core and organic side groups that are covalently bonded to the vertices of the inorganic polyhedron and are generally thought to bridge the gaps between organic and inorganic materials. Through a wise chemical selection, properties that best represent each component can be obtained. Structure (III) is an idealized POSS cage with two polymerizable groups, the remaining vertices containing isobutyl cosubstituted groups. POSS III is commercially available from Hybrid Plastics (Hattiesburg, Mississippi) under product number HC0709.13. TIFF2026521590000005.tif86148
[0022] Highly functionalized POSS cages can be bonded to each other through acrylate side groups during polymerization. The cages are essentially prepolymers or macromers due to their high molecular weight (generally exceeding 1000 amu) and high functionality. The functionality is fixed in place during polymerization and extends throughout the material, minimizing phase separation. This leads to isobutyl side groups extending throughout the polymer matrix.
[0023] A POSS cage is part of a polymer backbone having polymer chains extending from each side of the cage. These POSS molecules can be classified as telechelic monomers, which polymerize with themselves or other monomers to incorporate the POSS cage into the polymer backbone. These can then be considered telechelic oligomers. Telechelic monomers / oligomers / polymers are biterminally functional polymers, where both ends possess the same functionality. In this way, flexible polymerizable groups can be used to incorporate cage-like silicones into the polymer backbone, creating flexible and durable materials. According to aspects of the present invention, a POSS cage having two polymerizable groups enables the design of contact lens materials that can be either soft or hard and simultaneously exhibit high oxygen transport.
[0024] Furthermore, POSS cages with a single polymerizable group are also useful. For example, a POSS cage incorporating a propyl methacrylate polymerizable group can be incorporated into a polymer network as a pendant POSS cage. The remaining side groups can be numerous organic moieties. For example, but not limited to, an isobutyl side group forms a crystalline product, commercially available as a white powder under product number MA0702 from Hybrid Plastics (Hattiesburg, Mississippi). The crystallinity of the isobutyl product suggests that the molecule has a single cage structure, as generally represented by POSS structure IV. In a further example, the incorporation of an isooctyl side group forms an amorphous POSS molecule with a general structure represented as POSS V, commercially available as a clear liquid under product number MA0719 from Hybrid Plastics (Hattiesburg, Mississippi). In contrast to POSS IV, the isooctyl derivatized cage of POSS V can be a mixture of cages of different sizes. In other words, POSS V can be a mixture of silsesquioxane cages containing 8, 10, or 12 silicon atoms. It should also be noted that each POSS molecule can be a mixture of silsesquioxane cages having functionalities (e.g., methacrylate side groups) randomly distributed around the cage. For this purpose, the diagrams do not represent the exact structure, but rather idealized structures. Unlike POSS(IV), which is a crystalline compound with a precise structure and cage size of 8 silicon atoms, amorphous POSS(VI) is a mixture containing larger cages that are both open and closed. POSS(VI) is more compatible with other monomers in the formulation. It is more soluble in organic solvents than crystalline POSS(IV).
[0025] According to a further aspect of the present invention, a method for producing a high Dk material (Dk greater than 100) comprises contacting and reacting the following: one or more POSS methacrylates, an alkyl glycol dimethacrylate, a hydrophilic agent such as methacrylic acid, a methacrylic functional tris(trimethylsiloxy)silane, a methacrylic functional terminal polydimethylsiloxane, and a styryltris(trimethylsiloxy)silane. As an example, but not limited to, POSS may be a combination of structure (III)HC0709.13 and structure (IV)MA0702, which is isobutyl POSS; alkyl glycol dimethacrylate may be neopentyl glycol dimethacrylate; methacrylic functional tris(trimethylsiloxy)silane may be 3-methacryloyloxypropyltris(trimethylsiloxy)silane; and methacrylic functional terminal polydimethylsiloxane may be 4-methacryloyloxybutyl terminal polydimethylsiloxane. Further exemplary compositions may also include the addition of 1,3-bis(3-(methacrylateoxy)propyl)-1,1,3,3-tetrakis(trimethylsiloxy)disiloxane (tris dimer).
[0026] The reaction may be carried out in an inert atmosphere (e.g., under nitrogen, argon, and / or helium) at a temperature sufficient to produce a high-Dk material over a period of time. The reaction may be carried out at room temperature, e.g., about 20°C to about 25°C if a photoinitiator is present, or at a high temperature such as up to about 100°C if a thermal initiator is added to the formulation. As a result, the high-Dk material may have a Dk value greater than 100. In further embodiments, the high-Dk material produced according to the present invention does not require surface treatment such as plasma treatment if a hydrophilic agent such as methacrylic acid is incorporated into the polymer matrix. In addition, as used herein, the terms “about” and “approximately” in relation to any value shall be interpreted as being within plus or minus 5 percent (+ / -5%) of the described value.
[0027] advantage The exemplary, non-limiting advantages of the present invention are: a) Fluorine is not present in the polymer matrix. b) The material is mainly composed of several different forms of siloxane, c) The material must be transparent. d) The dried material is hard enough to be formed into an ophthalmic lens on a lathe. e) The material can be polymerized in a mold and directly formed into a lens or button. f) The level of crosslinking can be controlled by mixing a POSS cage having a single polymerizable group with a POSS cage having two or more polymerizable groups, and g) Less shrinkage occurs during polymerization due to the higher molecular weight of the POSS macromer. It may include. [Examples]
[0028] The following embodiments are for demonstrative purposes only and are not intended to limit this disclosure to them.
[0029] I. Thermal polymerization for forming rods Non-fluorinated RGP samples containing 40% POSS (replacing HFIPMA) were prepared as described below. Polymer rods containing POSS were formed into discs or buttons in three cases. The buttons were light-transmitting and possessed good mechanical properties suitable for lathe cutting into lenses. The compositions of the examples are listed in Table 1 shown in Figure 1. Oxygen permeability was measured using a Dk polarographic cell and reported in Table 2, as shown in Figure 2, along with hardness and appearance. It should also be noted that, alternatively, buttons or lenses could be formed directly from polypropylene molds using ultraviolet or blue light.
[0030] Examples 1-3, as shown in Table 1, were prepared by thermal polymerization using the peroxide initiator LUPEROX P. Each of Examples 1-3 consisted of 90% by weight or more of siloxane monomer and was fluorine-free. Polymerization was carried out under nitrogen at 55 and 95°C. Each temperature was achieved by holding it for 24 hours with a stepwise increase of 6 hours. The polymerized rods were removed from the tube casing and annealed at 120°C for 24 hours. Extraction of residual monomers and oligomers was performed by immersion in dichloromethane (DCM) overnight. The level of extraction was low, and the shape of the buttons was not affected by the solvent. Note that the relative weight percentages of the composition components do not include any mass or related weight percentages added by the initiator(s).
[0031] The tan delta peaks shown in Figure 2 (Table 2) were obtained by dynamic mechanical analysis (DMA) and represent the glass transition temperature (Tg) of the buttons between 140 and 155°C. The Shore D hardness of Examples 1 and 2 was 70 and 72, respectively. The Dk of each example was determined from the reciprocal of the slope of the lines in Figures 3-5. Note that Comparative Example 1 did not contain any POSS material but was instead made from fluoroacrylate. As can be seen in Figure 2, the properties of this example were similar to those of the comparative example, but notably, it did not contain fluoroacrylate or any other fluorinated material.
[0032] II. Photopolymerization for Button Formation Polymer buttons were formed by photopolymerization in a nitrogen chamber at room temperature. Using polypropylene molds, buttons with a diameter of approximately 15 mm and a thickness of 5 mm were produced. The polymerization time was approximately 10 minutes using a Dymax 400W floodbulb light curing system with a peak at 370 nanometers. The compositions are summarized in Table 3 in Figure 6. As can be seen in Figure 6, none of Examples 4-13 contain fluorine. Similar to the thermal polymerization described above, the POSS cage provides good mechanical properties while simultaneously providing a full silicone network. Thus, the POSS macromer offers all the advantages of fluoroacrylate without introducing a PFAS moiety. It should also be noted that Comparative Examples 2 and 3 employ the same fluorinated composition as Comparative Example 1 (Figure 1).
[0033] As shown in Table 3 of Figure 6, Examples 4, 6, 8, and 10 have the same compositions as 5, 7, 9, and 11, respectively, except that the even sets used the UV initiator 2-hydroxy-2-methylpropiophenone, while the odd sets used the blue light initiator diphenyl-(2,4,6-trimethylbenzoyl)phosphine oxide (TPO). The experiments used various combinations of POSS III and POSS IV (Table 3). Note that POSS V in Examples 4-11 was photopolymerized with HMPP in Example 12 and with TPO in Example 13.
[0034] All buttons were transparent and showed little extraction after overnight immersion in DCM. The mechanical properties of Examples 4–13 are summarized in Table 4 in Figure 7 and are consistent with properties useful for shaping into contact lenses. Examples 12 and 13 demonstrated that amorphous POSS molecules with one polymerizable group (POSS V) can be polymerized into a transparent polymer material with mechanical properties consistent with gas-permeable lenses. Note that Examples 4–11 (POSS IV) also formed a transparent material with mechanical properties consistent with gas-permeable lenses.
[0035] As plotted in Figure 8, where Examples 4, 6, and 8 are represented by squares and Examples 5, 7, and 9 are represented by circles, the maximum value of the tan (delta) peak is the measured glass transition temperature by DMA. As can be seen in Figure 8, the Tg is higher when the amount of crosslinking agent is increased, as reflected in the increased level of bifunctional POSS III (HC0709.13), which leads to a higher Tg.
[0036] As can be seen from the above explanation and in consideration of the drawings, the properties of materials made from POSS compounds are similar to those of materials made from fluorinated monomers. Therefore, in contrast to current state-of-the-art technology, contact lens materials can be manufactured without the use of fluorine.
[0037] The detailed description provided herein in relation to the accompanying drawings is intended to describe exemplary embodiments in which the subject matter of this disclosure may be put into practice. The term “exemplary” as used throughout this description means “to serve as an example, case, or illustration” and should not necessarily be construed as preferred or advantageous over other embodiments.
[0038] The above description of embodiments is provided to enable those skilled in the art to construct and use the subject matter. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the novel principles and subject matter disclosed herein may be applied to other embodiments without the use of innovative capabilities. The present invention is not intended to be limited to the embodiments shown herein, but rather to be granted the broadest scope consistent with the principles and novel features disclosed herein. Additional embodiments are intended to fall within the spirit and true scope of the disclosed subject matter.
Claims
1. A transparent polymer material that is fluorine-free and has high oxygen permeability, a) At least one silicone cage compound having at least one polymerizable pendant group and up to seven side chains, b) At least one acrylic compound, c) At least one acrylate-functionalized compound, d) Styryltris(trimethylsiloxy)silane and Includes, All of the compounds constituting the aforementioned transparent polymer material do not contain elemental fluorine. The aforementioned fluorine-free transparent polymer material.
2. A fluorine-free transparent polymer material according to claim 1, wherein Dk is approximately 150 and Shore D hardness exceeds 70.
3. A fluorine-free transparent polymer material according to claim 1, wherein Dk is approximately 125 and Shore D hardness exceeds 70.
4. The fluorine-free transparent polymer material according to claim 1, wherein the at least one silicone cage constitutes at least 40% by weight of the polymer material.
5. The fluorine-free transparent polymer material according to claim 1, wherein the at least one silicone cage is a first polyhedral oligomer silsesquioxane (POSS) monomer having one polymerizable methacrylate pendant group and seven isoalkyl side chains.
6. The fluorine-free transparent polymer material according to claim 5, wherein the at least one silicone cage is a second POSS monomer having two polymerizable methacrylate pendant groups and six isoalkyl side chains.
7. The fluorine-free transparent polymer material according to claim 6, wherein the isoalkyl side chains of the first POSS monomer and the second POSS monomer are isobutyl side chains, isooctyl side chains, or both.
8. The fluorine-free transparent polymer material according to claim 6, wherein the isoalkyl side chains of the first POSS monomer and the second POSS monomer are all isobutyl side chains.
9. A fluorine-free transparent polymer material according to claim 1, further comprising at least one disiloxane compound.
10. The fluorine-free transparent polymer material according to claim 9, wherein the at least one disiloxane compound is 1,3-bis(3-(methacryloxy)propyl)-1,1,3,3-tetrakis(trimethylsiloxy)disiloxane.
11. The fluorine-free transparent polymer material according to claim 1, wherein the at least one acrylic compound is methacrylic acid.
12. The fluorine-free transparent polymer material according to claim 1, wherein the at least one acrylate-functionalized compound is one or more of alkyl glycol dimethacrylate, methacrylic-functionalized tris(trimethylsiloxy)silane, and methacrylic-functionalized terminal polydimethylsiloxane.
13. The fluorine-free transparent polymer material according to claim 12, wherein the alkyl glycol dimethacrylate is neopentyl glycol dimethacrylate.
14. The fluorine-free transparent polymer material according to claim 12, wherein the methacrylic functional tris(trimethylsiloxy)silane is 3-methacrylicoxypropyltris(trimethylsiloxy)silane.
15. The fluorine-free transparent polymer material according to claim 12, wherein the methacrylic functionally terminated polydimethylsiloxane is 4-methacrylateoxybutyl terminated polydimethylsiloxane.
16. The fluorine-free transparent polymer material according to claim 12, wherein the at least one silicone cage, the styryltris(trimethylsiloxy)silane, the methacrylic functional tris(trimethylsiloxy)silane, and the methacrylic functional terminal polydimethylsiloxane constitute at least 90% of the transparent polymer material.
17. A fluorine-free transparent polymer material according to claim 1, further comprising a thermal polymerization initiator.
18. A fluorine-free transparent polymer material according to claim 1, further comprising a UV polymerization initiator.
19. A fluorine-free transparent polymer material according to claim 1, further comprising a blue photopolymerization initiator.