Method for recycling of thermoset spectacle lens material and related spectacle lens material

Abstract

The invention provides a method for recycling thermoset spectacle lens material by using a vitrification process. The invention also provides recycled thermoset spectacle lens material obtained thereby. Methods for manufacturing spectacle lens material and spectacle lens material manufactured thereby are also provided, which can be recycled using a vitrification process without the addition of extraneous substances.

Description

Technical Field

[0001] This invention relates to a method configured for recycling thermosetting spectacle lens material and the recycled thermosetting spectacle lens material. The invention further relates to a method configured for manufacturing recyclable thermosetting spectacle lens material and the thermosetting spectacle lens material manufactured therefrom. Background Technology

[0002] In the ophthalmology industry, thermosetting spectacle lens materials are currently widely used for spectacle lenses due to their superior properties, such as optical clarity and mechanical stability. However, due to their cross-linked structure, spectacle lenses cannot be reshaped or reprocessed after curing and are therefore not recyclable. Furthermore, potentially reusable spectacle lenses that fail quality control during production cannot be recycled. Instead, spectacle lens waste must be incinerated, discharged, or sent to landfills. Therefore, incineration, discharge, and disposal have negative economic costs and environmental impacts, such as the accumulation of plastics and microplastics and higher CO2 emissions. Moreover, these processes represent a waste of valuable resources.

[0003] Various solutions have been proposed and developed to address the plastic waste problem. Mechanical recycling involves processing plastic waste into secondary feedstocks without significantly altering the chemical structure of the material. For example, plastic waste can be converted into flakes, granules, or powders for reuse in the production of new materials. Chemical recycling, such as gasification, pyrolysis, solvent decomposition, alcoholysis, and / or depolymerization, aims to reduce the demand for primary fossil resources by altering the structure of polymer waste and converting it into chemical structural units, including monomers, which can then be reused as feedstocks in chemical processes. In particular, depolymerization processes use different combinations of chemicals, solvents, and heat to break down polymers into monomers and oligomers. Gasification and pyrolysis processes use heat and pressure to break down plastic waste into liquid, oily, or gaseous feedstocks, or a combination of both, for use as secondary feedstocks. Furthermore, recently, various chemicals have been adopted or developed with the aim of achieving reprocessable polymer networks, so-called covalently adaptive or associative networks (CANs) or dynamic covalent polymer networks (DCPNs), to allow for the reshapeability of cross-linked polymers. Such reshapeable polymers are also known as glass-like polymers. Associative CANs do not depolymerize upon temperature changes and exhibit a constant crosslinking density. Glass-like polymers are permanent networks of polymer chains linked by dynamic covalent bonds, which allows the network to change its topology while maintaining a constant number of chemical bonds. Dynamic covalent bonds are reversible and can rapidly reach thermodynamic equilibrium in response to stimuli. The process of changing the crosslinked or permanent network of a thermoset material into a covalently adaptive or dynamic network that can be reformed by applying specific stimuli (such as heating, light irradiation, etc.) is called vitrification. The term "catalytic vitrification" in this application refers to vitrification achieved through the use of a catalyst. Despite advances in vitrification technology in recent years, key issues remain unresolved for specific applications. Some vitrification processes have proven to deliver recycled materials of insufficient quality for further use or materials requiring additional processing steps that complicate and increase costs.

[0004] Each recycling process, including vitrification, is specifically designed and tailored to the type and characteristics of the plastic waste. Because each type of plastic waste has a different polymer structure, production method, and therefore different properties than different monomers, a recycling method suitable for one plastic polymer often proves unsuitable or even useless for another.

[0005] After extensive trial and error and research and development in every possible direction for recycling thermoset eyeglass lens materials, the inventors of this invention have discovered that certain thermoset eyeglass lens materials can exhibit dynamic behavior, thus exhibiting vitrification properties, and that specific vitrification processes result in recycled eyeglass lens materials with the superior qualities of eyeglass lenses. This behavior of thermoset plastics, exhibiting rearrangement of crosslinks within the polymer network under specific conditions, can lead to remolding of the material and stress relaxation within the material, thereby resulting in economical and feasible recycling of thermoset plastic eyeglass lens materials. Furthermore, based on the idea that certain thermoset eyeglass lens materials inherently contain exchangeable functional groups that result in covalently adaptive networks under specific conditions, the inventors have successfully derived a more economical recycling method for thermoset eyeglass lens materials, without even requiring the addition of additional raw materials or additional free reactive functional groups required in conventional vitrification processes during the recycling process. In addition, recyclable thermoset eyeglass lens materials have been successfully manufactured based on the new method.

[0006] Liang Yue et al., “Vitrimerization: A Novel Concept to Reprocess and Recycle Thermoset Waste via Dynamic Chemistry,” Global Challenges 2019, reported that thermoset materials with ester groups and freely available hydroxyl groups can be impregnated with catalysts and transformed into glass-like polymers. However, this method is difficult to apply to target thermoset eyeglass lens materials because the target thermoset eyeglass lenses do not possess the aforementioned specific functional groups. Furthermore, the recycled eyeglass lens materials exhibit reduced properties, such as ultimate strength and ductility.

[0007] William R. Dichtel et al., in “Reprocessable Acid-Degradable Polycarbonate Vitrimers”, Macromolecules, 51, 2018, 389–397, described the synthesis and remolding of polycarbonate-based glass polymers containing free hydroxyl groups in the polymer backbone. Specifically, the material was synthesized from cyclic carbonates and diols using tetrakis(isopropoxytitanium) as a catalyst. This material, along with the recycled material, exhibited insufficient optical properties for use as spectacle lens materials, particularly showing significant yellowness as can be seen from the corresponding figures. Furthermore, the softening temperature of approximately 50°C used herein is insufficient for use as spectacle lens materials.

[0008] Francesco Gamardella et al., "Recyclable poly(thiourethane) vitrifiers with high Tg. Influence of the isocyanate structure," Reactive and Functional Polymers 151 (2020), successfully reshaped several polythiourethanes synthesized using three different isocyanates. Specifically, trimethylolpropane tris(mercaptopropionate) was mixed with different diisocyanates and catalysts. However, the resulting recycled polymers exhibited a significant increase in yellowness, as clearly seen in the figures. This confirms that the obtained recycled polymers are unsuitable for use as eyeglass lens materials.

[0009] US 10822467 B2 is based on the idea of ​​using covalent adaptive networks and discloses a method for producing recyclable thermosetting compositions comprising one or more ester-based polyurethanes or epoxy resins, in combination with a catalyst in liquid form. To initiate the reaction, the method contacts the polymer with the liquid catalyst. However, this disclosure specifically relates to the use of transesterification, and therefore uses polymers containing ester groups in the polymer backbone and even structurally containing available hydroxyl groups. This method necessarily requires the polymer to have both ester and hydroxyl groups for the reaction to take place. No teaching is given regarding the possibility of recycling thermosetting spectacle lens materials that do not contain ester or epoxy groups. Furthermore, US10822467 B2 notes that the vitrified compositions exhibit yellowness due to the incorporation of the catalyst, indicating that the recycled ester-based thermosetting polymers and the proposed recycling method are unsuitable for producing lens materials.

[0010] Despite the fact that the general concept of vitrification and its various applications in different thermoset materials have been studied and are known as explained above, it remains unclear and highly unpredictable whether vitrification will be successful in a particular thermoset product and ultimately lead to a recycled product with the desired properties (which can be used directly as a lens material for eyeglasses). Summary of the Invention

[0011] Beginning with US 10822467 B2, the object of this invention is to provide a recycling method particularly suitable for several thermosetting plastic eyeglass lens materials, which allows the recycled materials to be reused as eyeglass lens materials. Furthermore, in one embodiment of the invention, no additional reactive groups are required for recycling. This will add significant value to the eyeglass lens industry by creating a circular economy without any intermediate steps.

[0012] According to a first aspect of the invention, a method configured for recycling thermosetting spectacle lens material is provided. The method provides thermosetting spectacle lens material in particulate and / or powder form, or uses thermosetting spectacle lens material in particulate and / or powder form, and provides a catalyst that enables and / or particularly promotes a reversible exchange reaction of at least one functional group of the thermosetting spectacle lens material, wherein the catalyst is dissolved and / or dispersed in a solvent.

[0013] Spectrum lens materials are optical materials defined as transparent materials capable of being manufactured into optical components, according to section 3.3.1 of DIN EN ISO 13666:2019-12. Thermosetting spectrum lens materials can be made from thermosetting hard resins according to section 3.3.3 of DIN EN ISO 13666:2019-12. The thermosetting spectrum lens materials of the present invention include, but are not limited to, polyurethane, polycyclic cyclic sulfides, polyallyl diethylene glycol carbonate, polyurethane, and / or polyurethane / polyurea. For example, the thermosetting spectrum lens material according to the present invention can be at least one of the optical materials mentioned in the table below.

[0014] Table 1: Examples of thermosetting optical materials Trademark Name Optical materials CR-39, CR-330, CR-607, CR-630, RAV 700, RAV 7NG, RAV 7AT, RAV710, RAV 713, RAV 720 Polyallyl diethylene glycol carbonate (PADC) RAVolution polyurethane Trivex Polyurea / Polyurethane MR-6, MR-8, MR-7, MR-10 Polysulfuric acid MR-174 Polycyclic sulfides The thermosetting spectacle lens material used as a starting material in this invention can be further defined as a thermosetting spectacle lens material with a yellowness index (YI) of 5.5 or less, preferably 2.5 or less, more preferably 1.5 or less. The yellowness index in this invention is measured according to ASTM E313. By starting with a material having a relatively low yellowness index compared to other vitrification processes, the method of this invention also successfully obtains recycled thermosetting spectacle lens materials with low yellowness, which can be remanufactured into optical components, particularly spectacle lenses.

[0015] Furthermore, the present invention uses a catalyst dissolved and / or dispersed in a solvent and provides thermosetting spectacle lens materials in the form of particles and / or powders, which are particularly suitable for recycling thermosetting spectacle lens materials while maintaining optical properties suitable for spectacle lenses. This means that thermosetting spectacle lens materials recycled according to the first aspect of the present invention can be reused as spectacle lens materials, i.e., spectacle lenses.

[0016] In a particularly preferred embodiment, the method of the present invention provides recycled thermosetting spectacle lens material having a yellowness index (YI) of 5.5 or less, preferably 2.5 or less, more preferably 1.5 or less. Because the recycled thermosetting spectacle lens material exhibits a specific yellowness index range within the specific yellowness index range of the original thermosetting spectacle lens material, the recycled material can be reused as spectacle lens material. If this yellowness index range cannot be obtained, the thermosetting spectacle lens material is downgraded for recycling and cannot be used to produce spectacle lenses, as is the case in the aforementioned prior art. Utilizing this feature, the method of the present invention creates a circular economy for thermosetting spectacle lens materials and adds significant economic value to the spectacle lens industry.

[0017] In a preferred embodiment, the recycled thermosetting spectacle lens material prepared according to the present invention has a haze of 2.0 or less, preferably 1.0 or less. Haze is a measure of the amount of light diffused or scattered when passing through a material. The haze in this invention is measured according to ASTM D1003.

[0018] Once prepared, the thermosetting spectacle lens material undergoes a process that transforms the spectacle lens material into smaller particles and / or powders, or the thermosetting spectacle lens material is provided in smaller sizes such as particles and / or powders. In a preferred embodiment, the thermosetting spectacle lens material is ground. The term "particle" according to the invention refers to any small-sized fragment of spectacle lens material, including flakes, pieces, fragments, fine particles, etc.

[0019] Providing spectacle lens materials in the form of smaller fragments, such as particles and / or powder, significantly increases the surface area of ​​thermosetting spectacle lens materials and facilitates the transformation of the cross-linked network of thermosetting spectacle lens materials into a covalently adaptive network, thus vitrifying. It has also been found that providing thermosetting spectacle lens materials in the form of particles and / or powder can potentially reduce the yellowness index and / or haze of recycled spectacle lens materials by increasing uniformity and shortening recycling process time, allowing recycled materials to be reused in spectacle lens materials, thereby creating a circular economy.

[0020] For the above process, any conventional apparatus suitable for thermosetting materials can be used, including but not limited to cryogenic mills, jaw crushers, rotor mills, cutting mills, knife grinders, mortar and pestle mills, disc mills, and ball mills. During this process, it is desirable to apply minimal thermal stress to the material, as thermal stress can cause partial changes in the thermosetting spectacle lens material, which in turn can lead to an increase in yellowness index or haze. In this sense, cryogenic milling, including cooling of the grinding jar, may be preferred. Furthermore, excessive heat is attributed to thermal stress and can cause undesirable reactions that increase the color of the material and, among other properties, an increase in haze. Therefore, since the heating duration or even the heating intensity can be reduced by minimizing the size of the material before subjecting it to subsequent steps in the recycling process, improved properties are provided for delivering starting materials in particulate and / or powder form to the recycled spectacle lens material. The specific type of apparatus used for this process can be selected based on the characteristics of the thermosetting spectacle lens material.

[0021] Preparing thermosetting spectacle lens materials to a smaller size means smaller than spectacle lens materials, and in a preferred embodiment, the thermosetting spectacle lens material is processed into particles with a diameter of 2.5 mm or less, more preferably 2.0 mm or less, and most preferably 1.0 mm or less. Within these ranges, the uniformity of the starting material increases, which may result in superior properties of the recycled material.

[0022] In this invention, a catalyst is added to a thermosetting eyeglass lens material. The catalyst according to the method of the invention is one capable of achieving, and particularly promoting, a reversible exchange reaction of at least one type of functional group within the material. The term "reversible exchange reaction" refers to a dynamic covalent bond exchange mechanism that allows glass-like polymers to undergo rearrangement while maintaining a covalently cross-linked network. Unlike conventional depolymerization processes, here, the glass-like polymers remain cross-linked but reorganized, and can be reshaped without complete melting, enabling recycling. The catalyst transforms the thermosetting eyeglass lens material into a glass-like polymer. That is, the catalyst achieves and / or promotes catalytic vitrification. By using a suitable type and form of catalyst, a dynamic network can be more easily achieved, resulting in a lower yellowness index, lower haze, and superior mechanical properties in the resulting material. The functional groups undergoing the reversible exchange reaction by the catalyst according to the invention are, but are not limited to, thiourethane groups, urethane groups, urea groups, carbonate groups, and / or disulfide groups. In a preferred embodiment, the functional group is at least one selected from the group consisting of thiourethane functional groups, urethane functional groups, urea functional groups, carbonate functional groups, and disulfide functional groups. Reversible exchange reactions between functional groups increase the mobility within the network of the thermosetting material. Under these conditions, the material can be manipulated to the extent that it can be repaired or its shape completely altered. Introducing dynamic covalent bonds into the network structure results in recyclable and reusable thermosetting materials.

[0023] The catalyst should be further selected taking into account the specific type and characteristics of the thermosetting spectacle lens material undergoing the recycling process. Any catalyst can be appropriately selected and used to achieve and / or promote the reversible exchange reaction of at least one type of functional group in the thermosetting spectacle lens material while producing recycled thermosetting spectacle lens material with sufficient optical properties.

[0024] Suitable catalysts would be metal-based catalysts, such as those based on zinc, tin, magnesium, cobalt, calcium, titanium, bismuth, iron, hafnium, lanthanum, samarium, dysprosium, erbium, ytterbium, and zirconium, in combination with organic ligands. Example compounds could be dibutyltin dilaurate (DBTDL), dibutyltin dichloride, zinc diacetate, di(2-ethylhexanoate)tin, bis(2-ethylhexanoate)dibutyltin, dibutyltin diacetate, bis(2,4-glutaric acid)dibutyltin, monobutyltin oxide, zinc dioctanoate, tetra(2-ethylhexanoate)titanium, lanthanides, trifluoromethanesulfonates, etc.; metal-free acidic catalysts, such as isopropyl methanesulfonate (IMS); and metal-free basic catalysts, such as pyridine or tertiary amines like triethylamine (TEA). Other metal-free basic catalysts could be, for example, 1,5-diazabicyclo[4.3.0]non-5-ene (DBN), 1,8-diazabicyclo[5.4.0]undec-7-ene (DBU), 1,5,7-triazabicyclo[4.4.0]dec-5-ene (TBD); suitable potential basic catalysts would be, for example, tetraphenylborates or tertiary ammonium salts of organic bases such as DBU, DBN, TBD, 1-methylimidazole, 4-dimethylaminopyridine (DMAP), or benzoates of organic bases such as DBU, DBN, TBD, 1-methylimidazole, DMAP; suitable catalysts would further be phosphorus-based catalysts, such as triphenylphosphine.

[0025] In a preferred embodiment, a metal-based catalyst is used. Metal-based catalysts have been found to be particularly suitable for recycling thermosetting spectacle lens materials, and because they produce recycled products with excellent optical properties, they can be reused as spectacle lens materials. In an embodiment where no metal-based catalyst is used, a basic catalyst is preferred over other catalysts because a faster reaction rate has been observed in leading to a reduction in reprocessing time in thermosetting spectacle lens materials compared to other catalysts. In another preferred embodiment, aromatic catalysts are avoided because they have been found to increase the yellowness index of the recycled thermosetting spectacle lens materials. Therefore, in a preferred embodiment, the catalyst used in the method of the present invention can be defined as any catalyst capable of achieving, and particularly promoting, a reversible exchange reaction of at least one functional group, except for catalysts that degrade the optical quality of the recycled spectacle lens materials.

[0026] In the method of this invention, it is important that the catalyst is dissolved and / or dispersed in a solvent before use. By doing so, the catalyst can uniformly contact the starting material and provide recycled material with high quality. The catalyst is placed in a solvent and becomes a solution or dispersion, and then placed to contact the thermosetting eyeglass lens material. The solvent according to the invention is a solvent capable of dissolving and / or dispersing the corresponding catalyst. The solvent can cause the thermosetting eyeglass lens material to swell. Preferred solvents are organic solvents, including but not limited to dichloromethane (DCM), tetrahydrofuran (THF), N,N-dimethylformamide (DMF), dimethyl sulfoxide (DMSO), acetone, ethyl acetate, acetonitrile, and toluene. The inventors have unexpectedly discovered that, by using a catalyst dissolved or dispersed in a solvent, in contrast to methods using catalysts in solid or pure form, recycled thermosetting materials with properties suitable for optical applications, such as yellowness index and haze, are obtained.

[0027] The amount of catalyst can be selected by considering the type of catalyst, the type of thermosetting spectacle lens material to be recycled, and other process conditions such as temperature, pressure, and process duration. On the other hand, the amount of catalyst should be carefully determined to obtain recycled thermosetting spectacle lens material with the optical properties required for use as spectacle lens material. In one embodiment, the amount of catalyst may be between 0.005 and 20 wt%, preferably 0.01 to 15 wt%, more preferably 0.01 to 10 wt%, and most preferably 0.01 to 5 wt% of the starting thermosetting spectacle lens material. For example, if DBTDL is used as the catalyst, 0.2 to 10 wt%, preferably 5 to 10 wt%, would be ideal for polyurethane / polyurea spectacle lenses or polycyclic sulfide spectacle lenses. Low catalyst concentrations may result in poor reprocessability and affect the recycling capacity of the spectacle lens material, while excessively high catalyst concentrations may lead to deterioration of the optical properties of the recycled product.

[0028] After converting the material into smaller particles and / or powder, the catalyst is mixed and diffused into the thermosetting spectacle lens material. In one embodiment, additional external stimuli such as high temperature or elevated temperature or high pressure or elevated pressure can be used to promote vitrification. The method of the present invention can be carried out at high temperatures, preferably above the glass transition temperature (Tg) of the thermosetting spectacle lens material. The term "glass transition temperature" refers to a temperature below which the fully or partially amorphous polymer is in a glassy or hard-elastic, brittle state, and above which it is in a highly viscous or rubbery state. The glass transition temperature can be determined, for example, by differential scanning calorimetry or dynamic mechanical analysis. "High temperature" can be achieved by heating and / or raising the temperature via input energy. If the process is carried out at a sufficiently high temperature, exchange reactions between reactive groups can be promoted. Carrying out the process at temperatures below the glass transition temperature of the spectacle lens material may result in poor reprocessability and affect the recyclability of the spectacle lens material. For example, in the case of polyallyl diethylene glycol carbonate, the optical reaction temperature can be between 110°C and 150°C.

[0029] In one embodiment, the increased heat and pressure required for vitrification can be achieved using a hot press, infrared heating, induction heating, microwave heating, photo-induced heating, autoclave treatment, etc. In a preferred embodiment, recycled thermoset eyeglass lenses are manufactured, as in the working example, by compression molding using hot pressing.

[0030] The glass-like polymer obtained by the method of the present invention, namely the recycled thermosetting spectacle lens material with a covalently adaptive network, is in solid form.

[0031] The method of the present invention is particularly advantageous because it eliminates the need to add additional starting materials containing additional free functional groups that participate in the reversible exchange reaction for vitrification. Here, the term "additional free functional groups" refers to free functional groups added, in the form of starting materials or compounds containing free functional groups, in addition to those already present in the spectacle lens material. These additional free functional groups are present in excess in the mixture with the spectacle lens material to be recycled.

[0032] In this case, the thermosetting spectacle lens material according to the invention already and essentially contains free functional groups that can potentially undergo reversible exchange reactions. In this particularly preferred embodiment, the thermosetting spectacle lens material may be selected from the group consisting of polyurethane, polycyclic sulfides, polyurethane, and polyurethane / polyurea.

[0033] In one embodiment, the network of the thermosetting spectacle lens material containing the catalyst is transformed into a covalently adaptive network based on thiotranscarbamylation or transcarbamylation. In this case, the thermosetting spectacle lens material is a polythiourethane spectacle lens material, or a polyurea / polyurethane spectacle lens material, or a polyurethane spectacle lens material.

[0034] The polysulfuron spectacle lens material according to the present invention can be obtained from (i) a polyisocyanate compound and (ii) a polythiol compound. The polysulfuron spectacle lens material comprises thiouron groups and thiol groups; or comprises thiouron groups. Specific examples of polysulfuron spectacle lens materials may include, but are not limited to, MR-6 (refractive index: 1.60), MR-7 (refractive index: 1.67), MR-8 (refractive index: 1.6), and MR-10 (refractive index: 1.67) from Mitsui Chemicals.

[0035] When mixed and impregnated with a catalyst dissolved and / or dispersed in a solvent, polythiourethane eyeglass lens materials undergo a reversible exchange mechanism based on a thiotranscarbamylation reaction. Specifically, in polythiourethane eyeglass lens materials containing thiol and thiourethane groups in their polymer structure, for example, thiol groups (HSR2 in Scheme 1 below) and thiourethane groups (R1S-C(O)NHR in Scheme 1) undergo a reversible exchange reaction in chemical equilibrium as shown in Scheme 1 upon mixing, and a catalyst in liquid form is added thereto, increasing the migration rate within the network of the eyeglass lens material.

[0036] [Option 1] On the other hand, in polythiourethane eyeglass lens materials containing thiol groups and thiourethane (thiocarbamate) groups or only thiourethane groups in the polymer chain, the thiourethane groups can also undergo an exchange reaction with another thiourethane group to form a dynamic covalent network.

[0037] In both cases, since the thiol groups are already present in the polyurethane spectacle lens material or are not required by the vitrification process, it is not necessary to add additional raw materials containing additional free thiol groups for the vitrification process.

[0038] Similarly, covalent adaptive networks can also be generated based on transcarbamylation reactions within polyurethane and polyurea / polyurethane eyeglass lens materials.

[0039] Polyurethane eyeglass lens materials can be obtained from (i) polyisocyanate compounds and (ii) polyol compounds. Polyurethane eyeglass lens materials contain urethane groups or contain both urethane groups and hydroxyl groups. Therefore, polyurethane eyeglass lens materials include urethane bonds. Specific examples of polyurethane eyeglass lens materials may include, but are not limited to, RAVolution (refractive index: 1.50) from Mitsui Chemicals. Unlike conventional techniques, since the hydroxyl groups are already contained in the polyurethane eyeglass lens material, or because transcarbamylation occurs between urethane bonds, it is not necessary to add additional raw materials containing free hydroxyl groups separately.

[0040] The polyurea / polyurethane spectacle lens material according to the present invention can be obtained from (i) polyisocyanate compounds, (ii) polyol compounds, and (iii) polyamine compounds. The polyurea / polyurethane spectacle lens material contains urea groups and urethane groups in the polymer, and optionally hydroxyl and / or amino groups. Therefore, the polyurea / polyurethane spectacle lens material contains urethane bonds and urea bonds. Specific examples of polyurethane / polyurea spectacle lens materials may include, but are not limited to, Trivex (refractive index: 1.53) from PPG Industries. Unlike conventional techniques, since hydroxyl and / or amino groups are already present in the polyurea / polyurethane spectacle lens material, or because transcarbamylation occurs between urethane bonds, it is not necessary to add hydroxyl or amine raw materials separately.

[0041] In another embodiment, the thermosetting spectacle lens material is based on the metathesis transformation of disulfide into a covalently adaptive network. In this case, the thermosetting spectacle lens material is a polycyclic sulfide spectacle lens material containing disulfide bonds.

[0042] Polycyclic sulfide (PCS) eyeglass lens materials can be obtained by reacting at least one PCS (PCS) monomer or oligomer with at least one thiol compound. PCS eyeglass lens materials contain disulfide groups, or a combination of disulfide and thiol groups.

[0043] Specific examples of polycyclic sulfide spectacle lens materials may include, but are not limited to, the high refractive index materials described in US 10954341 B2. When mixed with a catalyst dissolved and / or dispersed in a solvent, the polycyclic sulfide spectacle lens materials undergo a reversible exchange mechanism based on disulfide exchange reactions (disulfide metathesis) and / or disulfide-thiol exchange reactions, as illustrated in schemes 2 and 3 below.

[0044] [Option 2] [Option 3] Because minimal foreign material is added to the thermosetting spectacle lens material, the quality and properties of the recycled material (including reduced yellowness) are significantly enhanced, and the recycled material can be reused as spectacle lens material. Furthermore, this method offers advantages in terms of economic feasibility and simplicity. Nevertheless, it should be noted that the method of the present invention does not exclude embodiments including steps involving the addition of additional free functional groups (such as hydroxyl, thiol, and / or amino groups) to the reaction, as will be explained below.

[0045] Furthermore, the inventors of this invention have, for the first time, successfully recycled polyallyl diethylene glycol carbonate (PEG) spectacle lens material by adding hydroxyl groups and a catalyst dissolved and / or dispersed in a solvent and transforming it into a covalently adaptive network based on carbonyl conversion. This is particularly noteworthy because no prior art has reported or successfully recycled PEG thermosetting materials with qualities suitable for recycling spectacle lens material for optical products.

[0046] The polyallyl diethylene glycol carbonate (PED) spectacle lens material according to the present invention can be obtained by polymerization or copolymerization of diethylene glycol dielyl carbonate. The PED spectacle lens material contains carbonate groups. Specific examples of PED spectacle lens materials include, but are not limited to, CR39, CR330, CR607, and CR630 (refractive index: 1.50) from PPG Industries, Ltd., and RAV 700, RAV 7NG, RAV 7AT, RAV710, RAV 713, and RAV 720 (refractive index: 1.50) from Mitsui Chemicals, Ltd.

[0047] When mixed and swollen in liquid form with a catalyst and free hydroxyl groups, the carbonate bonds in polyallyl diethylene glycol carbonate (PEG) eyeglass lens materials can exhibit covalent dynamic behavior via carbonyl conversion reactions. Unlike other thermosetting eyeglass lens materials described above, PEG eyeglass lens materials necessarily require additional free hydroxyl groups for vitrification. Therefore, in this embodiment, the method of the present invention is characterized by further including providing additional free hydroxyl groups to the PEG eyeglass lens material, as shown in embodiment 4.

[0048] [Option 4] This is particularly surprising because even with the introduction of foreign substances such as hydroxyl groups, the resulting recycled materials exhibit suitable yellowness indices and haze for eyeglass lenses, provided that the starting materials are provided in particulate and / or powder form and that the reaction is achieved and / or promoted by a catalyst dissolved and / or dispersed in a solvent.

[0049] The additional free hydroxyl groups can be provided by any polyol having two or more hydroxyl groups, such as, but not limited to: ethylene glycol, glycerol, pentaerythritol, dipentaerythritol (DPE).

[0050] Similarly, the method of the present invention for thermosetting spectacle lens materials other than polyallyl diethylene glycol carbonate spectacle lens materials may optionally include the step of adding additional free functional groups selected from the group consisting of hydroxyl, thiol, and / or amine groups to further promote the reaction. Additional reactive functional groups will further shorten the processing time, which ultimately reduces thermal stress.

[0051] Specifically, the method of recycling polyurethane spectacle lens material according to the present invention may optionally include the addition of additional free thiol groups; the method of recycling polyurethane spectacle lens material according to the present invention may optionally include the addition of additional free hydroxyl groups; the method of recycling polyurea / polyurethane spectacle lens material according to the present invention may optionally include the addition of additional free hydroxyl groups and / or amine groups; and the method of recycling polyallyl diethylene glycol carbonate spectacle lens material according to the present invention includes the addition of additional free hydroxyl groups.

[0052] The additional free thiol group can be provided by any polythiol having two or more thiol groups, such as, but not limited to: ethylene glycol dimercaptopropionate, ethylene glycol dimercaptoacetate, pentaerythritol tetramercaptopropionate, pentaerythritol tetramercaptoacetate, and trimethylolpropane trimercaptopropionate.

[0053] The additional free amine group can be provided by any polyamine having two or more amine groups, such as, but not limited to, ethylenediamine, diethylenetriamine, and tris(2-aminoethyl)amine.

[0054] Furthermore, the mixture of free hydroxyl groups, free thiol groups, and free amine groups can be provided by any polyfunctional compound having the corresponding functional groups, but is not limited to: mercaptoethanol, ethanolamine, and pentaerythritol trimercaptopropionate.

[0055] As used in the working example, additional free functional groups are added in small amounts. In one embodiment, this may be 15% or less by weight, or 10% or less by weight, or 5% or less by weight.

[0056] Furthermore, thermosetting eyeglass lens materials can further include additives such as colorants, UV absorbers, release agents, antioxidants, defoamers, and organic or inorganic particles. Surprisingly, even though commercially available eyeglass lenses contain these types of additives, and the starting materials of this invention also contain these additives, the optical quality and properties of the thermosetting eyeglass lens materials remain unchanged or do not significantly deteriorate after recycling. The inventors unexpectedly discovered that these additives do not significantly affect the optical quality and properties of the materials recycled by the method of this invention, and therefore do not necessarily need to be removed or separated from the used eyeglass lens materials. This leads to the economic feasibility and simplicity of the method.

[0057] After the thermosetting spectacle lens material, converted into smaller sizes such as particles and / or powder, swells in a solution and / or dispersion of a catalyst, optionally providing additional free functional groups (such as hydroxyl, thiol, and / or amine), the solution and / or dispersion is separated from the swollen thermosetting spectacle lens material, and excess catalyst and optional additional free functional groups are removed by a washing process using a suitable solvent. Excess solvent is then removed, and the swollen thermosetting spectacle lens material is dried. Appropriate solvent removal is preferred because solvent remaining on the surface and within the polymer network will adversely affect the optical and mechanical properties of the recovered material.

[0058] The mixture of thermosetting spectacle lens material and catalyst can then be formed in the desired form under high temperature and pressure using conventional lens manufacturing techniques such as pressing, injection molding, and extrusion. The temperature and pressure can be set according to conventional spectacle lens production conditions. The temperature can be between 70°C and 250°C, preferably 70°C to 200°C, more preferably 100°C to 200°C, and most preferably 110°C to 150°C. The pressure can be between 1 and 20 MPa, preferably 5 to 18 MPa. In one embodiment, a hot press is used to mold the thermosetting spectacle lens material and catalyst.

[0059] The recycled spectacle lens material produced in this way shows no significant loss in mechanical, thermal, or optical properties. Haze and yellowness indices are also observed to be suitable for further optical applications of spectacle lenses.

[0060] Therefore, the method of the present invention can be a method configured to manufacture spectacle lenses using such recycled spectacle lens material. Furthermore, the method of the present invention can repeatedly recycle spectacle lenses manufactured from the recycled spectacle lens material. This manufacturing method cuts, preferably grinds, the spectacle lenses manufactured from the recycled spectacle lens material into smaller sizes such as particles and / or powder, and reshapes the cut or ground spectacle lenses without adding a catalyst. Since the catalyst is already present in the spectacle lens material manufactured from the spectacle lens material recycled by the method of the present invention, subsequent recycling of the spectacle lenses no longer requires the addition of a catalyst.

[0061] All matters explained above with respect to the first aspect of the invention also apply to the second, third, fourth and fifth aspects of the invention, unless otherwise specifically explained.

[0062] According to a second aspect of the invention, a recycled thermosetting plastic eyeglass lens material produced by a method according to a first aspect of the invention is provided. The recycled thermosetting eyeglass lens material still contains a catalyst that enables and / or promotes a reversible exchange reaction of at least one functional group in the thermosetting eyeglass lens material and catalytic vitrification of the thermosetting eyeglass lens material during subsequent recycling. The phrase "during subsequent recycling of the recycled thermosetting eyeglass lens material" refers to further recycling that occurs after the already recycled thermosetting eyeglass lens material has been used and discarded. Since the catalyst used in the vitrification recycling process is not consumed, the catalyst remains in the recycled thermosetting plastic eyeglass lens material and can be used in the next vitrification recycling process. This significantly contributes to the circular economy of eyeglass lens materials. The recycled thermosetting plastic eyeglass lens material is characterized by having a yellowness index (YI) of 5.5 or less, preferably 2.5 or less, more preferably 1.5 or less. The recycled thermosetting plastic eyeglass lens material may further be characterized by having a haze of 2.0 or less, preferably 1.0 or less. It was not until this invention that recyclable thermosetting plastic materials with a yellowness index and / or haze suitable for eyeglass lenses were made available.

[0063] Recycled thermosetting eyeglass lens materials can be selected from the group consisting of polyurethane, polycyclic sulfides, polyallyl diethylene glycol carbonate, polyurethane, and / or polyurethane / polyurea. Furthermore, since recycled thermosetting eyeglass lens materials can also be recycled using commercially available eyeglass lenses, they can further contain additives such as colorants, UV absorbers, mold release agents, antioxidants, defoamers, and organic or inorganic particles.

[0064] As explained with respect to the first aspect of the invention, the catalyst of the invention is not limited, as long as it can realize and / or particularly promote reversible exchange reactions of one or more types of functional groups. The catalyst of the invention undergoes catalytic vitrification.

[0065] According to a third aspect of the invention, a method configured to manufacture a thermosetting spectacle lens material is provided, the thermosetting spectacle lens material being recyclable without the addition of any foreign substances. The thermosetting spectacle lens material according to the third aspect of the invention can be recycled and manufactured into spectacle lenses by being provided in smaller sizes such as particles and / or powders, and then shaped into a desired form at high temperature and pressure via conventional lens manufacturing techniques such as compression molding, injection molding, and extrusion. The method is configured to manufacture a thermosetting spectacle lens material that can be recycled without the addition of any foreign substances by preparing a thermosetting polymer while mixing a catalyst capable of achieving and / or promoting a reversible exchange reaction of at least one functional group in the thermosetting polymer and catalytic vitrification during subsequent recycling of the recyclable thermosetting spectacle lens material. "Thermosetting polymer" refers to the polymer that forms the basis of the recyclable thermosetting spectacle lens material. The term "preparation" means the polymerization of the polymer. In other words, the method provides a thermosetting polymer in which monomers and / or oligomers of the thermosetting polymer are mixed with a catalyst that enables and / or promotes a reversible exchange reaction of at least one functional group in the thermosetting polymer.

[0066] The thermosetting spectacle lens material thus obtained has a yellowness index of 5.5 or less, preferably 2.5 or less, more preferably 1.5 or less, exhibiting optical properties suitable for spectacle lens materials. The thermosetting spectacle lens material can further exhibit a haze of 2.0 or less, preferably 1.0 or less. This is unexpected because foreign substances such as catalysts are included in the spectacle lens material. Furthermore, an advantage of the obtained thermosetting spectacle lens material is that it can be recycled, producing recycled spectacle lens material with a yellowness and / or haze within substantially the same range suitable for spectacle lens materials.

[0067] The thermosetting polymer according to the third aspect of the invention is at least one selected from the group consisting of polyurethane, polycyclic sulfides, polyallyl diethylene glycol carbonate, polyurethane, and polyurethane / polyurea. All the features relating to the thermosetting spectacle lens material and catalyst explained with respect to the first aspect of the invention apply respectively to the thermosetting polymer and catalyst of the third aspect of the invention.

[0068] The catalyst according to the third aspect of the invention need not be dissolved and / or dispersed in a solvent, as it is added from the beginning of the manufacturing process of the thermosetting spectacle lens material. The catalyst according to the third aspect must be soluble in the mixture of monomers and / or oligomers and / or optional additives before curing the mixture to obtain the thermosetting spectacle lens material.

[0069] A fourth aspect of the invention relates to a method configured to recycle spectacle lens material manufactured according to a third aspect of the invention. The method includes providing thermosetting spectacle lens material manufactured according to the third aspect of the invention, cut into smaller sizes such as particles and / or powder, and further includes reshaping the spectacle lens material without the addition of a catalyst capable of achieving and / or promoting a reversible exchange reaction of at least one functional group in the thermosetting polymer, thereby catalytic vitrification. The recycled thermosetting spectacle lens material also exhibits a yellowness index of 5.5 or less, preferably 2.5 or less, more preferably 1.5 or less, and / or a haze of 2.0 or less, preferably 1.0 or less. The spectacle lens material can be recycled multiple times through simple process steps while exhibiting excellent optical properties.

[0070] According to a fifth aspect of the invention, a thermosetting spectacle lens material is provided, which is recyclable without the addition of any foreign substances and contains a catalyst dissolved in a solvent, the catalyst being capable of realizing or promoting a reversible exchange reaction of at least one functional group. The term "foreign substance" refers to any substance that is not part of the original composition of the thermosetting spectacle lens material. This includes, but is not limited to, additional catalysts, free functional groups, and other external additives. The thermosetting spectacle lens is characterized by having a yellowness index of 5.5 or less, preferably 2.5 or less, more preferably 1.5 or less, and / or a haze of 2.0 or less, preferably 1.0 or less. Here, the thermosetting spectacle lens material is selected from the group consisting of polyurethane, polycyclic sulfides, polyallyl diethylene glycol carbonate, polyurethane, and polyurethane / polyurea. All the features concerning the thermosetting spectacle lens material and catalyst explained with respect to the first aspect of the invention apply respectively to the thermosetting polymer and catalyst of the fifth aspect of the invention.

[0071] Specifically, the fifth aspect of the invention relates to a thermosetting spectacle lens composition comprising a thermosetting spectacle lens material, characterized in that the composition further comprises a catalyst that enables and / or promotes a reversible exchange reaction of at least one functional group in the thermosetting spectacle lens material and catalytic vitrification during the subsequent recycling of the manufactured spectacle lens, wherein the thermosetting spectacle lens composition and spectacle lenses manufactured therefrom have a yellowness index of 5.5 or less as measured according to ASTM E313 and / or a haze of 2.0 or less as measured according to ASTM D1003, and the manufactured spectacle lenses can be recycled by vitrification without the addition of foreign substances. Since the composition contains a catalyst for vitrification from the outset, it can be easily recycled without any foreign substances, which adds a significant advantage in efficiency to the recycling process. Furthermore, the invention also relates to spectacle lens materials manufactured using the thermosetting spectacle lens composition according to the fifth aspect, which can be recycled by vitrification without the addition of foreign substances. Detailed Implementation

[0072] In summary, the following embodiments and features are particularly preferred within the scope of the present invention: Example 1a. A method configured for recycling thermosetting spectacle lens material, the method comprising: The thermosetting spectacle lens material is supplied in smaller sizes, for example, as granules and / or powder. A catalyst is provided that enables and / or promotes a reversible exchange reaction of at least one functional group in the thermosetting spectacle lens material. The characteristic feature is that the catalyst is dissolved and / or dispersed in a solvent.

[0073] Example 2a. The method according to Example 1a, characterized in that the thermosetting spectacle lens material has a yellowness index of 5.5 or less, preferably 2.5 or less, more preferably 1.5 or less.

[0074] Example 3a. The method according to any one of the foregoing embodiments, characterized in that the thermosetting spectacle lens material has a haze of 2.0 or less, preferably 1.0 or less.

[0075] Example 4a. The method according to any one of the foregoing embodiments, characterized in that the particles of the thermosetting spectacle lens material have a particle size of 2.5 mm or less, more preferably 2.0 mm or less, and most preferably 1.0 mm or less.

[0076] Example 5a. The method according to any one of the foregoing embodiments, characterized in that the thermosetting spectacle lens material is selected from the group consisting of polyurethane, polycyclic sulfide, poly(allyl diethylene glycol carbonate), polyurethane, and polyurethane / polyurea.

[0077] Example 6a. The method according to any one of the foregoing embodiments, characterized in that the thermosetting spectacle lens material is selected from the group consisting of CR39, CR-330, CR-607, CR-630, RAV 700, RAV 7NG, RAV 7AT, RAV 710, RAV713, RAV 720, MR174, RAVolution, Trivex, MR-6, MR-8, MR-7 and MR-10.

[0078] Example 7a. The method according to any one of the foregoing embodiments, characterized in that the thermosetting spectacle lens material is selected from the group consisting of CR39, CR-330, CR-607, CR-630, RAV 700, RAV 7NG, RAV 7AT, RAV 710, RAV713, RAV 720 and MR-174.

[0079] Example 8a. The method according to any one of the foregoing embodiments, characterized in that no additional free functional groups are added, wherein the thermosetting spectacle lens material is selected from the group consisting of polyurethane, polycyclic sulfide, polyurethane, and polyurethane / polyurea.

[0080] Example 9a. The method according to any one of Examples 1a to 7a, characterized in that additional free functional groups are added.

[0081] Example 10a. The method according to the previous example, characterized in that these additional free functional groups are selected from the group consisting of hydroxyl, thiol and amine groups.

[0082] Example 11a. The method according to any one of the foregoing embodiments, characterized in that additional free functional groups or additional free thiol groups are added, wherein the thermosetting spectacle lens material is a polyurethane spectacle lens material.

[0083] Example 12a. The method according to any one of the foregoing embodiments, characterized in that additional free functional groups or additional free hydroxyl groups are added, wherein the thermosetting spectacle lens material is a polyurethane spectacle lens material.

[0084] Example 13a. The method according to any one of the foregoing embodiments, characterized in that additional free functional groups, additional free hydroxyl groups and / or additional free amine groups are added, wherein the thermosetting spectacle lens material is a polyurea / polyurethane spectacle lens material.

[0085] Example 14a. The method according to the previous example, characterized in that additional free amine groups are added.

[0086] Example 15a. The method according to any one of the foregoing embodiments, characterized in that additional free functional groups or additional free hydroxyl groups are added, wherein the thermosetting spectacle lens material is a polyallyl diethylene carbonate spectacle lens material.

[0087] Example 16a. The method according to any one of the foregoing embodiments, characterized in that additional free functional groups or additional free thiol groups are added, wherein the thermosetting spectacle lens material is a polycyclic sulfide spectacle lens material.

[0088] Example 17a. The method according to any one of the foregoing embodiments, characterized in that the thermosetting spectacle lens material further comprises at least one additive selected from the group consisting of colorants, UV absorbers, release agents, antioxidants, defoamers, and organic or inorganic particles.

[0089] Example 18a. The method according to any one of the foregoing embodiments, characterized in that the catalyst is a metal-based catalyst.

[0090] Example 19a. The method according to any one of the foregoing embodiments, characterized in that the recycled thermosetting spectacle lens material has a yellowness index of 5.5 or less, preferably 2.5 or less, more preferably 1.5 or less.

[0091] Example 20a. The method according to any one of the foregoing embodiments, characterized in that the recycled thermosetting spectacle lens material has a haze of 2.0 or less, preferably 1.0 or less.

[0092] Example 21a. The method is configured to manufacture thermosetting spectacle lenses using recycled thermosetting spectacle lens material according to any of the relevant foregoing examples.

[0093] Example 22a. A thermosetting spectacle lens material manufactured by the method described in accordance with the preceding example.

[0094] Example 1b. A recycled thermosetting spectacle lens material comprising a catalyst capable of enabling or promoting a reversible exchange reaction of at least one functional group in the thermosetting spectacle lens material, characterized in that the material has a yellowness index of 5.5 or less, preferably 2.5 or less, more preferably 1.5 or less.

[0095] Example 2b. The recycled thermosetting spectacle lens material according to Example 1b, characterized in that the material has a haze of 2.0 or less, preferably 1.0 or less.

[0096] Example 3b. The recycled thermosetting spectacle lens material according to the preceding example, characterized in that it is selected from the group consisting of polyurethane, polycyclic sulfide, polyallyl diethylene glycol carbonate, polyurethane, and polyurethane / polyurea.

[0097] Example 4b. The recovered thermosetting spectacle lens material according to any one of the foregoing embodiments, characterized in that the recovered thermosetting spectacle lens material is a polycyclic sulfide.

[0098] Example 5b. The recycled thermosetting spectacle lens material according to any one of the foregoing embodiments, characterized in that it further comprises an additive selected from at least one of colorants, release agents, UV absorbers, antioxidants, defoamers, and organic or inorganic particles.

[0099] Example 6b. The recovered thermosetting spectacle lens material according to any one of the foregoing embodiments, characterized in that the catalyst is a metal-based catalyst.

[0100] Example 1c. A method configured to manufacture thermosetting spectacle lens material using a thermosetting polymer, characterized in that a catalyst is mixed during the preparation of the thermosetting polymer, the catalyst realizing or promoting a reversible exchange reaction of at least one functional group in the thermosetting polymer.

[0101] Example 2c. The method according to the previous example, characterized in that the thermosetting spectacle lens material has a yellowness index of 5.5 or less, preferably 2.5 or less, more preferably 1.5 or less.

[0102] Example 3c. The method according to any one of the foregoing embodiments, characterized in that the thermosetting spectacle lens material has a haze of 2.0 or less, preferably 1.0 or less.

[0103] Example 4c. The method according to any one of the foregoing embodiments, characterized in that the thermosetting polymer is selected from the group consisting of polysulfuric ester, polycyclic sulfide, polyallyl diethylene glycol carbonate, polyurethane, and polyurethane / polyurea.

[0104] Example 7c. The method according to any one of the foregoing embodiments, characterized in that no additional free functional groups are added, wherein the thermosetting spectacle lens material is selected from the group consisting of polyurethane, polycyclic sulfide, polyallyl diethylene glycol carbonate, polyurethane, and polyurethane / polyurea.

[0105] Example 8c. The method according to any one of Examples 1c to 7c, characterized in that additional free functional groups are further added.

[0106] Example 9c. The method according to the preceding example, characterized in that these additional free functional groups are selected from the group consisting of hydroxyl, thiol and amine groups.

[0107] Example 10c. The method according to any one of the foregoing embodiments, characterized in that additional free functional groups or additional free thiol groups are added, wherein the thermosetting spectacle lens material is a polyurethane spectacle lens material.

[0108] Example 12c. The method according to any one of the foregoing embodiments, characterized in that additional free functional groups or additional free hydroxyl groups are added, wherein the thermosetting spectacle lens material is a polyurethane spectacle lens material.

[0109] Example 13c. The method according to any one of the foregoing embodiments, characterized in that additional free functional groups, additional free hydroxyl groups and / or additional free amine groups are added, wherein the thermosetting spectacle lens material is a polyurea / polyurethane spectacle lens material.

[0110] Example 14c. The method according to the previous example, characterized in that additional free amine groups are added.

[0111] Example 15c. The method according to any one of the foregoing embodiments, characterized in that additional free functional groups or additional free hydroxyl groups are added, wherein the thermosetting spectacle lens material is a polyallyl diethylene carbonate spectacle lens material.

[0112] Example 16c. The method according to any one of the foregoing embodiments, characterized in that additional free functional groups or additional free thiol groups are added, wherein the thermosetting spectacle lens material is a polycyclic sulfide spectacle lens material.

[0113] Example 17c. The method according to any one of the foregoing embodiments, characterized in that the catalyst is a metal-based catalyst.

[0114] Example 18c. The method is configured to recycle spectacle lens material manufactured according to any of the foregoing embodiments. The method is characterized by further comprising: In the absence of a catalyst, spectacle lens material is pressed and cut into smaller sizes, such as particles and / or powder, whereby the catalyst enables or promotes a reversible exchange reaction of at least one functional group of the thermosetting spectacle lens material.

[0115] Example 19c. A thermosetting spectacle lens material manufactured by the method according to any one of the foregoing examples.

[0116] Example 1d. A thermosetting spectacle lens material comprising a catalyst that enables or promotes a reversible exchange reaction of at least one functional group in the thermosetting spectacle lens material, characterized in that the material has a yellowness index of 5.5 or less, preferably 2.5 or less, more preferably 1.5 or less.

[0117] Example 2d. The thermosetting spectacle lens material according to the previous example, characterized in that the material has a haze of 2.0 or less, preferably 1.0 or less.

[0118] Example 3d. A thermosetting spectacle lens material according to any one of the foregoing embodiments, characterized in that the thermosetting spectacle lens material is selected from the group consisting of polyurethane, polycyclic sulfides, polyallyl diethylene glycol carbonate, polyurethane, and polyurethane / polyurea.

[0119] Example 4d. The thermosetting spectacle lens material according to any one of the foregoing embodiments, characterized in that the recycled thermosetting spectacle lens material is a polycyclic sulfide.

[0120] Example 5d. A recyclable thermosetting spectacle lens material according to any one of the foregoing embodiments, characterized in that the catalyst is a metal-based catalyst.

[0121] Example 6d. A recyclable thermosetting spectacle lens material according to any one of the foregoing embodiments, characterized in that the thermosetting spectacle lens material can be recycled without adding foreign substances.

[0122] Example 7d. A thermosetting spectacle lens material according to any one of the foregoing embodiments, characterized in that the thermosetting spectacle lens material is selected from the group consisting of polyurethane, polyurethane, and polyurethane / polyurea.

[0123] The invention can be further explained based on the following experimental examples.

[0124] Example 1 50 g of MR-7 material from Mitsui Chemicals was cryogenically ground to an average particle size of 1.5 mm. The ground material was mixed with a 10 wt% solution of DBTDL in THF. The mixture was kept at 50°C for 4 days. Afterward, the mixture was filtered and the remaining solid was washed with THF. The resulting solid was dried under vacuum for 12 hours and pressed using a hot press at 110°C and 8 MPa for 2 hours. The resulting sample showed a yellowness index below 5.5.

[0125] Example 2 50 g of MR-8 material from Mitsui Chemicals was cryogenically milled to an average particle size of 2.0 mm. The milled material was mixed with a solution of 10 wt% DBTDL and 5 wt% ethylene glycol di(mercaptopropionate) in dichloromethane. The mixture was kept at room temperature for 48 hours. Afterward, the mixture was filtered and the remaining solid was washed with dichloromethane. The resulting solid was dried under vacuum for 12 hours and pressed using a hot press at 120°C and 10 MPa for 2.5 hours. The resulting sample showed significantly faster stress relaxation compared to the original MR-8 material.

Claims

1. A method configured for recycling thermosetting spectacle lens material, the method comprising, Provide a catalyst to the thermosetting spectacle lens material, The thermosetting eyeglass lens material is in the form of granules and / or powder, and The catalyst enables and / or promotes a reversible exchange reaction of at least one functional group in the thermosetting spectacle lens material, thereby catalytic vitrification of the thermosetting spectacle lens material. Its features are, The thermosetting spectacle lens material has a yellowness index of 5.5 or less as measured by ASTM E313 and / or a haze of 2.0 or less as measured by ASTM D1003. The catalyst is provided by dissolving and / or dispersing it in a solvent, and The recycled thermosetting eyeglass lens material has a yellowness index of 5.5 or less as measured by ASTM E313 and / or a haze of 2.0 or less as measured by ASTM D1003.

2. The method according to claim 1, Its features are, No additional free functional groups are added. The thermosetting spectacle lens material is selected from at least one of the groups consisting of polyurethane, polycyclic sulfide, polyurethane, and polyurethane / polyurea.

3. The method according to claim 2, Its features are, The thermosetting eyeglass lens material is a polycyclic sulfide.

4. The method according to claim 1, Its features are, Add additional free functional groups, in (a) The additional free functional group is a thiol group, and the thermosetting spectacle lens material is a polyurethane spectacle lens material. (b) The additional free functional group is a hydroxyl group, and the thermosetting spectacle lens material is a polyallyl diethylene glycol carbonate spectacle lens material. (c) The additional free functional group is a thiol group, and the thermosetting spectacle lens material is a polycyclic sulfide spectacle lens material. (d) The additional free functional group is a hydroxyl group, and the thermosetting spectacle lens material is a polyurethane spectacle lens material, or (e) The additional free functional group is a hydroxyl group and / or an amino group, and the thermosetting spectacle lens material is a polyurea / polyurethane spectacle lens material.

5. The method according to any one of the preceding claims, Its features are, The thermosetting eyeglass lens material further comprises an additive selected from at least one of colorants, UV absorbers, release agents, antioxidants, defoamers, and organic or inorganic particles.

6. A method configured to manufacture thermosetting spectacle lenses, comprising manufacturing thermosetting spectacle lenses using thermosetting spectacle lens material recovered by the method according to any one of the preceding claims.

7. A recycled thermosetting spectacle lens material comprising a catalyst that enables and / or promotes a reversible exchange reaction of at least one functional group in the thermosetting spectacle lens material and catalytic vitrification of the thermosetting spectacle lens material during subsequent recycling. Its features are, It has a yellowness index of 5.5 or less as measured by ASTM E313 and / or a haze of 2.0 or less as measured by ASTM D1003.

8. The recycled thermosetting spectacle lens material according to claim 7, characterized in that, The recycled thermosetting eyeglass lens material is at least one selected from the group consisting of polyurethane, polycyclic sulfide, polyallyl diethylene glycol carbonate, polyurethane, and polyurethane / polyurea.

9. The recycled thermosetting spectacle lens material according to claim 7 or 8, characterized in that, The recycled thermosetting eyeglass lens material is either polycyclic sulfide or polyallyl diethylene glycol carbonate.

10. A method configured to manufacture recyclable thermosetting spectacle lens material using a thermosetting polymer, Its features are, The thermosetting polymer is provided, wherein monomers and / or oligomers of the thermosetting polymer are mixed with a catalyst that enables and / or promotes a reversible exchange reaction of at least one functional group in the thermosetting polymer and catalytic vitrification during subsequent recycling of the recyclable thermosetting spectacle lens material. The recyclable thermosetting eyeglass lens material has a yellowness index of 5.5 or less as measured by ASTM E313 and / or a haze of 2.0 or less as measured by ASTM D1003.

11. The method according to claim 10, Its features are, No additional free functional groups are added to the thermosetting polymer, wherein the thermosetting polymer is at least one selected from the group consisting of polyurethane, polycyclic sulfide, polyurethane, and polyurethane / polyurea.

12. The method according to claim 10, Its features are, Add other free functional groups, among which (a) The additional free functional group is a thiol group, and the thermosetting polymer is polyurethane. (b) The additional free functional group is a hydroxyl group, and the thermosetting polymer is polyurethane. (c) The additional free functional group is a hydroxyl group, and the thermosetting polymer is polyallyl diethylene glycol carbonate. (d) The additional free functional group is a thiol group, and the thermosetting polymer is a polycyclic sulfide, or (e) The additional free functional group is a hydroxyl and / or an amino group, and the thermosetting polymer is a polyurea / polyurethane.

13. A method configured to recycle recyclable thermosetting spectacle lens material, the recyclable thermosetting spectacle lens material being manufactured according to any one of claims 10 to 12, Its features are, Provide spectacle lens material prepared as particles and / or powder, and recycle the spectacle lens material without adding a catalyst that enables and / or promotes a reversible exchange reaction of at least one functional group of the thermosetting spectacle lens material.

14. A thermosetting spectacle lens composition for manufacturing spectacle lenses, the composition comprising a thermosetting spectacle lens material, Its features are, The composition further comprises a catalyst that enables and / or promotes a reversible exchange reaction of at least one functional group in the thermosetting spectacle lens material and catalytic vitrification during the recycling of the manufactured spectacle lens. The thermosetting spectacle lens composition and the manufactured spectacle lens have a yellowness index of 5.5 or less as measured according to ASTM E313 and / or a haze of 2.0 or less as measured according to ASTM D1003. The manufactured eyeglass lenses can be recycled through vitrification without the addition of foreign substances.

15. The thermosetting spectacle lens composition according to claim 14, Its features are, The thermosetting spectacle lens material is selected from the group consisting of polyurethane, polycyclic sulfides, polyurethane, and polyurethane / polyurea.

16. An eyeglass lens manufactured using the thermosetting eyeglass lens composition according to claim 14 or 15, Its features are, These eyeglass lenses can be recycled through vitrification without the addition of foreign substances.

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