Polymeric photochromic dyes having at least one and no more than four naphthopyran subunits and multiple polyether chains

Abstract

The present invention relates to novel polymeric photochromic dyes having at least one and no more than four naphthopyran subunits and a plurality of polyether chains, their use and photoresponsive color-changing acrylates, allyl carbonates, urea, carbamate or thiocarbamate polymers containing them, and photoresponsive color-changing products.

Description

[0001] This invention relates to novel polymeric photochromic dyes having at least one and at most four naphthopyran subunits and multiple polyether chains, phototropic acrylates, allyl carbonates, urea, urethane or thiourethane polymers comprising them, phototropic products, and uses of these photochromic dyes.

[0002] Thiocarbamate polymers are currently the most widely used materials for plastic eyeglasses, possessing a high refractive index of ≥ 1.60. A higher refractive index allows for thinner corrective lenses. However, to date, without the use of special additives, it has been impossible to directly incorporate photochromic dyes into thiocarbamate polymers and produce acceptable photoresponsive color-changing properties (deep darkening upon exposure to sunlight and rapid brightening after exposure ends). This is because the dense, three-dimensionally cross-linked polymer matrix of thiocarbamate thermosetting polymers used in high-quality plastic eyeglasses does not leave room for photochromic dyes to undergo reversible transformation (induced by long-wave UV radiation, changing from their colorless base state to their darkened state). Therefore, conventional photochromic dyes in thiocarbamate thermosetting polymers do not darken under sunlight, or only darken to a negligible degree. Therefore, surface coating with photochromic coatings (primarily through spin coating) has been the preferred method for producing photoresponsive photochromic plastic eyeglasses with a high refractive index. However, the drawback of this method is that it requires complex and expensive technical equipment and can only produce a relatively small number of products per unit of time, which leads to relatively high production costs.

[0003] It is well known that various types of dyes undergo reversible color changes under long-wave UV light (especially sunlight). This is because, due to light energy, these photochromic dye molecules transition from their colorless fundamental state (“closed form”) with selective bond breakage to a darkened state (“open form”). Upon interruption of the energy supply, they revert from the darkened state to the colorless fundamental state, thereby reforming the previously broken bonds. The most widely used type of dye for photochromic glasses is the naphthopyran system, particularly the naphthopyran system with an additional fused aromatic ring, which absorbs longer wavelengths in both closed and open colored forms due to its larger conjugated system. A benzene ring with an additional bridging at the ortho position is often used for fusion. In the compounds according to the invention described below, the benzene ring is connected via a single-atom bridge (with R7 and R8 substituents) or via a diatomic bridge (with R7, R8, and R...). 10 The substituents fused with the R9 substituent.

[0004] If a single-atom bridging exists, the five-membered ring is fused with a naphthopyran (“indeno-naphthopyran”). Examples can be found in EP 0 792 468 and EP 0 906 366. EP 0 912 908, EP 2 457 915, EP 2 471 794, EP 2684 886, EP 2 788 340, and EP 2 872 517 describe compounds in which at least one additional ring system is fused with an indeno-naphthopyran core structure. EP 3 807 258 describes a bis-indeno-fused naphthopyran system with longer-chain polyether substituents to improve photoresponsive color-changing properties.

[0005] If a diatomic bridging exists, the six-membered ring is fused with naphthopyran (“dihydronaphtho-naphthopyran”), as described in EP 1119 560, EP 2 829 537 and EP 3 010 924. Such compounds with longer-chain polyether substituents are also described in EP 3 807 258 above.

[0006] Therefore, this invention aims to provide novel photochromic dyes, particularly photochromic polymers in which the dyes are directly incorporated into thiocarbamate thermosetting polymers, resulting in photoresponsive color-changing polymers with excellent photosensitive color-changing properties, without the need for any special additives. With the help of these novel photochromic dyes, excellent photochromic properties (extremely deep darkening after exposure and extremely rapid brightening after exposure) can be achieved not only in the high-index range but also for low-index lenses, in a matrix-independent manner.

[0007] This objective is achieved through the subject matter embodied in the claims.

[0008] This invention is based on a surprising discovery: certain photochromic dye molecules with multiple polyether chains at different points in the molecule (containing one to four naphthopyran subunits) exhibit superior matrix-independent photochromic properties in all types of plastic eyeglasses, as described in EP 3 807 258 above, compared to systems with only one naphthopyran subunit and one polyether chain. Moreover, this is achieved without the need for special additives, whereas dyes with only one naphthopyran subunit and one long-chain polyether substituent exhibit unacceptable photochromic properties in densely crosslinked thiocarbamate thermosetting polymers without the aid of special additives.

[0009] EP 2 714 767 describes photochromic dyes having two (or more) naphthopyran subunits linked to each other by a polymer chain. Furthermore, EP 2 705 071 describes photochromic dyes having two (or more) naphthopyran subunits linked to each other by various types of polymer chains. However, the compounds described in these two documents also exhibit acceptable photoresponsive color-changing properties only in thiocarbamate thermosetting polymers with additional additives, as they contain only one linear polymer chain. In contrast, in the compounds according to the invention, the naphthopyran subunits (where there are more than one in the molecule) are linked to each other only by relatively short linkers, while multiple polymer polyether chains are each linked “outside” the molecule. This allows these long-chain polyether substituents to very effectively encapsulate the photochromic naphthopyran subunits, thereby completely isolating them from the corresponding plastic lens polymer matrix. This makes it possible, for the first time, to achieve excellent photochromic properties independently of the matrix—even in tightly cross-linked thiocarbamate thermosetting polymers.

[0010] According to the present invention, a novel polymeric photochromic dye having at least one and at most four naphthopyran subunits and a plurality of polyether chains is provided according to formula (I):

[0011]

[0012] (I)

[0013] Condition (1): At least one and at most four of the free radicals R1, R2, R3 and R4 independently represent the following groups A having terminal long-chain polyether substituents:

[0014]

[0015] (A)

[0016] Furthermore, the remaining free radicals R1, R2, R3, and R4 independently represent hydrogen, methyl radicals, ethyl radicals, phenyl radicals, or the following groups B having long-chain polyether substituents:

[0017]

[0018] (B)

[0019] In the case where there is only one group A in the molecule, at least one of the remaining free radicals must represent group B;

[0020] Or condition (2): at least one and at most two of the free radicals R1, R2, R3 and R4 independently represent the following group C:

[0021]

[0022] (C)

[0023] Furthermore, at least two of the remaining free radicals R1, R2, R3, and R4 represent groups B, wherein, in the case of additional remaining free radicals, the free radicals may be selected from hydrogen, methyl free radicals, ethyl free radicals, or phenyl free radicals;

[0024] Where m, n, p, q, and r independently represent integers from 0 to 1, s represents integers from 5 to 50, and t represents integers from 0 to 3.

[0025] In this context, the stylized benzene ring labeled "naphthopyran" represents one of the following four discrete naphthopyran subunits "1" to "4":

[0026]

[0027] And the above-mentioned substituents R5, R6, R7, R8, R9, R 10 R 11 and R 12 As defined in claim 1.

[0028] Another subject of the invention relates to photoresponsive color-changing acrylates, allyl carbonates, urea, urethanes, or thiourethane polymers comprising one or more of the above-described photochromic dyes.

[0029] In particular, the present invention also relates to photoresponsive color-changing products based on thiocarbamate polymers, wherein the photoresponsive color-changing products are two-component systems in which a 0.1 mm to 1 mm thin photoresponsive color-changing polythiocarbamate functional layer based on the thiocarbamate polymer is polymerized onto a polymer matrix, or the photoresponsive color-changing products are sandwich systems in which a 0.1 mm to 1 mm thin photoresponsive color-changing polythiocarbamate functional layer based on the thiocarbamate polymer is disposed between two polymer bodies.

[0030] Another subject of the invention relates to the use of the photochromic dyes according to the invention incorporation into thiocarbamate polymers, particularly for ophthalmic applications, for lenses and glasses of various spectacles such as corrective lenses, driving glasses, ski goggles, sunglasses, and motorcycle goggles, for helmet visors and the like, and for sunshade purposes in vehicles and in the construction industry in the form of windows, protective covers, canopies, roofs, and the like.

[0031] The compounds according to the invention are characterized in that the photochromic naphthopyran subunits are spatially adjacent to two or more polyether chains. The arrangement of these subunits around a central tetrahedral carbon atom allows the entire system to be spatially encapsulated within a polymer matrix. This spatial shielding of the photoresponsive naphthopyran subunits by long-chain polyether substituents achieves, for the first time, matrix-independent photoresponsive properties. Specifically, this means that photoresponsive properties can be achieved in thiocarbamates, urethanes, urea, acrylates, and allyl carbonates using the compounds according to the invention.

[0032] To date, achieving good photosensitive color-changing properties has required the use of a less tightly cross-linked (corresponding to lower hardness) specially tuned polymer matrix, or the addition of special additives. These additives, together with the dye, form a domain system that locally softens the polymer matrix. However, the formation of these domains is highly material-specific and can only be achieved in certain polymer matrices. However, the specific structure of the compounds according to the invention allows for the arrangement of long-chain polyether substituents adjacent to the pyran rings of the photosensitive naphthylpyran subunits. This is the point of greatest structural change during photosensitive switching, when the color changes from being turned on to a colored form or turned off to a colorless form. The opening and closing of the photosensitive center is unimpeded due to the loose arrangement (“random coils”) of the linear polyether chains with only minimal intramolecular interactions. Therefore, the photosensitive properties of the dyes according to the invention can also be achieved in highly cross-linked polymer matrices (e.g., thiocarbamate polymers).

[0033] Due to the special structure of the dyes and their "separation" from the surrounding polymer matrix, the photochromic dyes according to the present invention can achieve excellent darkening when exposed to sunlight and extremely rapid brightening after the exposure ends.

[0034] The bonding of the naphthopyran subunit in formula (I) to the central tetrahedral carbon atom occurs directly (for n = p = 0), via a succinyloxy bridge (for n = 1 and p = 0), or via an ethoxide-succinyloxy bridge (for n = p = 1).

[0035] Using succinyloxy bridging is advantageous because, when using novel coupling agents, ester bonds can be formed at very mild reaction temperatures (including room temperature), meaning that heating does not create thermal stress on the molecule and lead to thermal decomposition. Other coupling reactions (such as Williamson ether syntheses) require higher reaction temperatures and more intense reaction conditions (e.g., the use of strong bases).

[0036] To achieve a faster brightening rate, an ethoxy bridge is typically required between the naphthopyran subunit and the succinyloxy bridge. For naphthopyran systems, the faster the brightening from a dark state, the better the electron-donator properties of the substituents on the two benzene rings bonded to the carbon atom near the pyran oxygen. Therefore, it is advantageous to use two strong electron-donating alkoxy substituents, as the acyloxy substituents of the succinyloxy bridge directly on the naphthopyran subunit are too weak as electron donors, often resulting in insufficient brightening speed. The same applies to the succinyloxy bridge (for r = 1) connecting the naphthopyran subunit and the long-chain polyether substituent in the compounds according to the invention; condition (1) applies here.

[0037] The compound according to the invention under applicable condition (1) has one to four naphthopyran subunits and a total of two to four long-chain polyether substituents (distributed in groups A and B). The latter are each connected to the adjacent naphthopyran subunit via an optional ethoxide (for q = 1) and a succinyloxy bridge (for r = 1), or, if there are fewer than four naphthopyran subunits in the molecule, optionally additionally directly connected to the central tetrahedral carbon atom of formula (I), specifically as group B, connected via a succinyloxy bridge. This non-optional succinyloxy bridge in group B reappears for synthetic purposes. Under very mild reaction conditions, the coupling of the long-chain polyether substituents to the central tetrahedral carbon atom is achieved here via an ester bridge.

[0038] The compound according to the invention under condition (2) has one or two naphthopyran subunits and two or three long-chain polyether substituents. The latter, as group B, are each attached to a naphthopyran subunit via a central tetrahedral carbon atom. Compared to condition (1), there are no additional long-chain polyether substituents bonded to the naphthopyran subunits, but only a "smaller" substituent R6, which can influence the darkening color and the brightening rate.

[0039] For the synthesis of compounds according to the invention, suitable naphthopyran starting compounds known in principle in the prior art can be used, and for example according to Figure 1 and Figure 2 and 1 ,3-difunctional propane derivatives (where m = m' = 1) react to form molecules each having two naphthopyran subunits and at least two long-chain polyether substituents.

[0040] Figure 1 A synthetic scheme for compounds having two naphthopyran subunits according to the present invention is shown under applicable condition (1).

[0041] The starting compounds used here are naphthopyrans, each having a 4-hydroxyl substituent on one of two benzene rings bonded to a carbon atom adjacent to the pyran oxygen, and a long-chain polyether substituent on the other benzene ring, which is bonded via an optional ethoxide (for q = 1) and succinyloxy (for r = 1) bridge. Suitable polyether substituents particularly include commercially available long-chain polypropylene glycol monobutyl ethers, but also include polypropylene glycol / polyethylene glycol copolymers with a monoalkyl cap. The chain lengths exhibit a Gaussian distribution, i.e., there are mixtures of different chain lengths distributed near the maximum value. The synthesis of two molecules of these naphthopyran starting compounds via covalent coupling of a central tetrahedral carbon atom is carried out using Williamson ethers of 1,3-dibromopropane derivatives (where m = m' = 1). Alternatively, 1,2-dibromoethane (where R3 = R4 = H, m = 1 and m' = 0) can also be used.

[0042] If a 2-(bromomethyl)-1,3-dibromopropane derivative (R3 = CH2Br) is used, a three-molecule naphthopyran starting compound can be converted into a compound according to the invention containing three naphthopyran subunits. Accordingly, bis(2-bromomethyl)-1,3-dibromopropane (R3 = R4 = CH2Br) and a four-molecule naphthopyran starting compound yield a compound according to the invention having four naphthopyran subunits.

[0043] Figure 2 The synthesis scheme of the compound according to the invention under applicable conditions (2) is shown.

[0044] The starting compounds used here are naphthopyran starting compounds, which have a 4-succinyloxy substituent and an optional ethoxy bridge (for p = 1) on one of the two benzene rings bonded to the carbon atom next to the pyran oxygen, and a para-substituent R6 on the other benzene ring. The covalent coupling of two molecules of these naphthopyran starting compounds via a central tetrahedral carbon atom is achieved through a mild ester synthesis using a 1,1'-carbonyldiimidazole (CDI) and a 1,3-propanediol derivative (which has two long-chain polyether substituents (R3 = R4 = group B)). These 2,2-substituted 1,3-propanediol derivatives are readily available from the inexpensive precursor pentaerythritol.

[0045] Figure 3 The photoresponsive color-changing properties of three compounds according to the invention are shown in comparison with suitable reference compounds from the prior art (EP 3 807 258). All compounds contain a naphthopyran subunit "1" (the naphthopyran subunits protected in other claims behave very similarly in such comparisons). Figure 3The transmittance data are from measurements taken at 23°C according to DIN EN ISO 8980-3.

[0046] Measurements were performed using 2 mm thick polythiourethane discs. These discs were produced by thermally polymerizing photochromic dyes in a mold after dissolving them in a liquid monomer mixture of isocyanates and thiols suitable for high-quality plastic eyeglasses and adding a standard Sn catalyst.

[0047] Figure 3 The specific molecular structures of the compounds shown are listed in Table 1. Compounds 1 and 2 of the present invention are derived from Formula 1, Condition 1, and compound 3 of the present invention is derived from Formula 1, Condition 2.

[0048]

[0049]

[0050] Compound 1 of the present invention in Table 1 has two naphthopyran subunits connected via 1,3-propanediol bridges. The polypropylene glycol chain on each of the naphthopyran subunits is connected via a diol and a succinyloxy group bridge.

[0051] Compound 2 of the present invention in Table 1 has four naphthopyran subunits connected via pentaerythritol bridging. The polypropylene glycol chain on each naphthopyran subunit is directly connected to the naphthopyran subunit via an ether bond.

[0052] Compound 3 of the present invention in Table 1 has two naphthopyran subunits linked to the central molecule of pentaerythritol. The polypropylene glycol chain is bonded to each of the other two alcohol groups of pentaerythritol via succinyloxy bridges.

[0053] In contrast, the reference compound has only one polypropylene glycol chain and one naphthopyran subunit, thus reflecting the prior art. Here, the naphthopyran subunit is the same as that in compounds 1 to 3 of the present invention.

[0054] Figure 3 The results clearly show that the exact structure of the naphthopyran subunit plays only a minor role in this invention. The reference compound exhibits almost no photoresponsive color-changing properties, and its transmittance changes only slightly after UV irradiation. The photoresponsive color-changing properties of such compounds can only be manifested by using highly tailored matrices or special additives.

[0055] In contrast, compounds 1, 2, and 3 according to the invention exhibit good darkening depth and transmittance values ​​below 20% in the fully excited state. The arrangement of multiple naphthopyran subunits and polyether chains around a common center ensures an optimal environment for the dye, thus enabling photochromic properties to be exhibited in polythiourethane polymers that have not been optimized for this purpose, even without the use of special additives.

[0056] Furthermore, the reference compound exhibits a relatively low transmittance value in the unexcited state, at only about 77%. This indicates the presence of an open colored form of the photochromic dye, which lacks the ability to revert to its colorless fundamental state. Compounds 1, 2, and 3 of the present invention also address this problem because the dye is not prevented from reversing to its colorless fundamental state in the absence of light, thus allowing for significantly higher transmittance in the bright state.

[0057] Compounds 1, 2 and 3 of the present invention also exhibit very rapid brightening behavior.

[0058] These superior photochromic properties (high transmittance in bright conditions, deep darkening upon exposure, and very rapid brightening) can be achieved not only in polythiourethane matrices but also in other matrices suitable for plastic eyeglasses, such as polyurethane, poly(meth)acrylate, or polyallyl carbonate. Therefore, for the first time, a matrix-independent photochromic dye system exhibiting such properties is provided without the need for additional additives.

Claims

1. A photochromic dye according to the following formula (I), having at least one and at most four naphthopyran subunits and a plurality of polyether chains: (I) Condition (1): At least one and at most four of the free radicals R1, R2, R3 and R4 independently represent the following groups A having terminal long-chain polyether substituents: (A) Furthermore, the remaining free radicals R1, R2, R3, and R4 independently represent hydrogen, methyl radicals, ethyl radicals, phenyl radicals, or the following groups B having long-chain polyether substituents: (B) in, If there is only one group A in the molecule, at least one of the remaining free radicals must represent the group B; Or condition (2): at least one and at most two of the free radicals R1, R2, R3 and R4 independently represent the following group C: (C) Furthermore, at least two of the remaining free radicals R1, R2, R3, and R4 represent groups B, wherein, in the case of additional remaining free radicals, the free radicals may be selected from hydrogen, methyl free radicals, ethyl free radicals, or phenyl free radicals; Where m, n, p, q and r represent integers from 0 to 1 independently, s represents integers from 5 to 50, and t represents integers from 0 to 3; In this case, the free radicals R5 in the repeating units of chain length s independently represent either hydrogen or methyl free radicals; Wherein, the free radical R6 represents a substituent selected from the following: hydrogen, fluorine, (C1–C6)-alkyl radical, (C3–C7)-cycloalkyl radical, (C1–C6)-thioalkyl radical, (C1–C6)-alkoxy radical, trifluoromethyl radical, phenyl radical, 4-methoxyphenyl radical, phenoxy radical, 4-methoxyphenoxy radical, benzyl radical, 4-methoxybenzyl radical, benzyloxy radical, 4-methoxybenzyloxy radical, biphenyl radical, biphenoxy radical, naphthyl radical, naphthoxy radical, piperidinyl radical, 3,5-dimethylpiperidinyl radical, morpholinyl radical, 2,6- Dimethylmorpholinyl radical, thiomorpholinyl radical, azaheptanyl radical, indolyl radical, 1,2,3,4-tetrahydroquinolinyl radical, 1,2,3,4-tetrahydroisoquinolinyl radical, diphenylamino radical, ((C1–C6)-alkoxyphenyl)-phenylamino radical, bis((C1–C6)-alkoxyphenyl)amino radical, 10,10-dimethyl-9,10-dihydroacridyl radical, phenothiazinyl radical, phenotoxazinyl radical, phenothiazinyl radical, carbazoyl radical, 1,2,3,4-tetrahydrocarbazoyl radical, or 10,11-dihydro-dibenzo[b,f]azazoyl radical; In this context, the stylized benzene ring labeled "naphthopyran" represents one of the following four discrete naphthopyran subunits "1" to "4": Among them, free radicals R7, R8 and R 10 Each can independently represent a substituent selected from the following: (C1-C6)-alkyl radicals or phenyl radicals; The radical R9 independently represents a substituent selected from the following: (C1-C6)-alkyl radical, (C3-C7)-cycloalkyl radical, (C1-C6)-alkoxy radical, benzyl radical, or unsubstituted or monosubstituted phenyl radical, wherein the substituent may be selected from fluorine, (C1-C6)-alkyl radical or (C1-C6)alkoxy radical; and wherein k represents 0, 1 or 2; Alternatively, two adjacent R9 radicals can form a fused benzene ring, which can be unsubstituted, monosubstituted, or disubstituted, wherein the substituents can be selected from fluorine, (C1-C6)-alkyl radicals, (C1-C6)-alkoxy radicals, phenyl radicals, or benzyl radicals; Alternatively, two adjacent R9 radicals may form a fused naphthalene ring system, a fused benzofuran ring system, a fused benzothiophene ring system, a fused 3,3-dimethylindene ring system, or a fused 2H-chromene ring system. And free radical R 11 and R 12 Each of the substituents can be independently selected from the following: hydrogen, (C1-C6)-alkyl radical, (C3-C7)-cycloalkyl radical, trifluoromethyl radical, benzyl radical, or unsubstituted or monosubstituted phenyl radical, wherein the substituent can be selected from fluorine, (C1-C6)-alkyl radical or (C1-C6)-alkoxy radical; Or the free radical R 11 and R 12 Together they represent the group -(CH2). j - where j represents an integer from 1 to 3; provided that if the value is 2 or 3, the benzene ring can also be fused to two adjacent CH2 groups.

2. The photochromic dye according to claim 1, wherein the dye has the features of premise (1).

3. The photochromic dye according to claim 1, wherein the dye has the features of premise (2).

4. The photochromic dye according to any one of claims 1 to 3, wherein the stylized benzene ring labeled "naphthopyran" is selected from one of the above-mentioned naphthopyran subunits "1", "2" or "3".

5. The photochromic dye according to any one of claims 1 to 4, wherein the free radical R9 independently represents a substituent selected from the group consisting of (C1-C6)-alkyl radical, (C3-C7)-cycloalkyl radical, (C1-C6)-alkoxy radical, benzyl radical, or unsubstituted or monosubstituted phenyl radical, wherein the substituent may be selected from fluorine, (C1-C6)-alkyl radical or (C1-C6)-alkoxy radical; and wherein k represents 0, 1 or 2.

6. The photochromic dye according to any one of claims 1 to 5, wherein the free radical R 11 and R 12 Each of the substituents can be independently selected from the following: hydrogen, (C1-C6)-alkyl radical, (C3-C7)-cycloalkyl radical, benzyl radical, or unsubstituted or monosubstituted phenyl radical, wherein the substituent can be selected from fluorine, (C1-C6)-alkyl radical or (C1-C6)-alkoxy radical.

7. A photosensitive acrylate, allyl carbonate, urea, carbamate or thiocarbamate polymer comprising one or more photosensitive dyes according to any one of claims 1 to 6.

8. A photoresponsive color-changing product based on the thiocarbamate polymer according to claim 7, wherein the photoresponsive color-changing product is a two-component system, wherein a 0.1 mm to 1 mm thin photoresponsive color-changing polythiocarbamate functional layer based on the thiocarbamate polymer is polymerized onto a polymer matrix, or the photoresponsive color-changing product is a sandwich system, wherein a 0.1 mm to 1 mm thin photoresponsive color-changing polythiocarbamate functional layer based on the thiocarbamate polymer is disposed between two polymer bodies.

9. Use of the photochromic dye according to any one of claims 1 to 6 for incorporation into thiocarbamate polymers, particularly for ophthalmic applications, for lenses and eyeglasses of various eyeglasses such as corrective lenses, driving glasses, ski goggles, sunglasses, motorcycle goggles, for helmet visors and the like, and for sunshade purposes in vehicles and in the construction industry in the form of windows, protective covers, caps, roofs and the like.

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