Polycarbonate resin and optical member using the same

Abstract

A polycarbonate resin comprising a repeating unit represented by formula (1) and / or formula (2), a repeating unit represented by formula (3), and a repeating unit represented by formula (4), and being a polycarbonate resin or wherein the total of the repeating units represented by formula (1) and / or formula (2) in all the repeating units of the intermediate resin is 50 mol% or more, and the weight average molecular weight Mw is 10,000 or more, The total of the repeating units represented by formula (1) and / or formula (2) in all repeating units of the resin is more than 0 mol% and less than 50 mol%, and the weight average molecular weight Mw is 10,000 or more. (In the formula, R 1 ~R 4 each independently represents a hydrogen atom or a hydrocarbon group having 1 to 10 carbon atoms. ) (In formula (4), n is in the range of 0 to 8, and R each independently represents an alkyl group having 1 to 3 carbon atoms. )

Description

Technical Field

[0001] This disclosure relates to polycarbonate resins and optical components using the resin. Background Technology

[0002] While glass, traditionally used as a material in optical systems, can achieve various required optical properties and has excellent environmental resistance, it suffers from poor processability. To address this issue, resins, which are cheaper and have better processability than glass, have begun to be used in optical components.

[0003] In the optical design of optical units, it is known to correct chromatic aberration by combining multiple lenses with different Abbe numbers. For example, chromatic aberration can be corrected by combining lenses made of alicyclic polyolefin resin with low refractive index and high Abbe number with lenses made of bisphenol A type polycarbonate resin (nd = 1.59, νd = 31) with high refractive index and low Abbe number. In recent years, the development of resins with high refractive index and low Abbe number has become popular, and consequently, the demand for high Abbe number resins has also increased. For example, Patent Document 1 describes obtaining a polycarbonate resin with high Abbe number and low photoelasticity by copolymerizing 2,2-bis(4-hydroxyphenyl)propane (commonly known as bisphenol A) with pentacyclic pentadecanediethanol (hereinafter sometimes referred to as PCPDM). Furthermore, Patent Document 2 discloses a method for producing carbonate derivatives without the use of alkali by photoreacting a halomethane with a specific amount of a hydroxyl-containing compound in the presence of oxygen. As a manufacturing example, a copolymer of 9,9-bis[4-(2-hydroxyethoxy)phenyl]fluorene (hereinafter sometimes simply referred to as BPEF) and PCPDM is illustrated. Patent Documents 3 and 4 describe obtaining polycarbonate resins with high refractive index and low orientation birefringence by copolymerizing BPEF with 3,9-bis(2-hydroxy-1,1-dimethylethyl)-2,4,8,10-tetraoxaspiro(5,5)undecane (hereinafter sometimes simply referred to as SPG) and 4,4'-(3,3,5-trimethylcyclohexylidene)bisphenol (hereinafter sometimes simply referred to as BisTMC).

[0004] Furthermore, bisphenol A-type polycarbonate resins obtained by reacting bisphenol A with phosgene or carbonates are widely used not only as structural materials but also as optical materials in optical disc substrates, various lenses, prisms, and optical fibers due to their excellent heat resistance, transparency, and mechanical properties such as impact resistance. However, bisphenol A-type polycarbonate resins suffer from significant birefringence due to molecular orientation and residual stress during molding. Therefore, with the expanding applications of optical materials in recent years, there is a strong demand for materials with lower birefringence. For example, Patent Document 1 describes a method for reducing the birefringence of polycarbonate resins by copolymerizing bisphenol A with PCPDM to obtain a polycarbonate resin with a low photoelasticity coefficient. Patent Document 2 proposes a method for manufacturing carbonate derivatives without the use of alkali by photoreacting halomethane with a specific amount of hydroxyl-containing compound in the presence of oxygen. As a manufacturing example, a copolymer of BPEF and PCPDM is illustrated. Patent Documents 3 and 4 describe polycarbonate resins with low orientation birefringence obtained by copolymerizing BPEF, SPG, and BisTMC.

[0005] Existing technical documents

[0006] Patent documents

[0007] Patent Document 1: Japanese Patent Application Publication No. 2000-302860

[0008] Patent Document 2: WO2020 / 100977

[0009] Patent Document 3: WO2019 / 188702

[0010] Patent Document 4: WO2022 / 004239 Summary of the Invention

[0011] However, the polycarbonate resin composed of bisphenol A and PCPDM, besides having room for improvement in its photoelasticity, also suffers from high orientation birefringence. Furthermore, due to its high molecular weight, the resulting resin is unsuitable for injection molding and cannot be used in thin-walled optical components such as camera lenses. Additionally, the weight-average molecular weight of the BPEF / PCPDM copolymer polycarbonate is extremely low at 3360, making it unsuitable for use as a structural or optical material. Moreover, the polycarbonate resin composed of BPEF, SPG, and BisTMC exhibits a low Abbe number relative to its refractive index, and its photoelasticity also has room for improvement.

[0012] The first aspect of this disclosure was made in view of the above circumstances.

[0013] Therefore, the purpose of the first approach is to provide a polycarbonate resin with an excellent balance between refractive index and Abbe number, and thus a small birefringence and photoelasticity coefficient.

[0014] Furthermore, the polycarbonate resin composed of bisphenol A and PCPDM, besides exhibiting high orientation birefringence, also suffers from low refractive index and glass transition temperature. Additionally, due to its high molecular weight, the resulting resin is unsuitable for injection molding applications and cannot be used in thin-walled optical components such as camera lenses. Moreover, the weight-average molecular weight of the BPEF / PCPDM copolymerized polycarbonate is extremely low at 3360, making it unsuitable for use as a structural or optical material. Furthermore, the polycarbonate resin composed of BPEF, SPG, and BisTMC offers room for improvement in refractive index and glass transition temperature.

[0015] The second aspect of this disclosure was made in view of the above circumstances.

[0016] Therefore, the purpose of the second approach is to provide a polycarbonate resin with low orientation birefringence, high refractive index, and high glass transition temperature.

[0017] The inventors have discovered that the above-mentioned technical problems can be solved by the following methods.

[0018] The first approach disclosed herein includes the following schemes.

[0019] <1> A polycarbonate resin comprising repeating units represented by formula (1) and / or formula (2), repeating units represented by formula (3), and repeating units represented by formula (4), wherein the total of repeating units represented by formula (1) and / or formula (2) in all repeating units of the resin is 50 mol% or more, and the weight average molecular weight Mw of the polycarbonate resin is 10,000 or more.

[0020]

[0021]

[0022]

[0023] (where R) 1 ~R 4 Each can independently represent a hydrogen atom or a hydrocarbon group with 1 to 10 carbon atoms.

[0024]

[0025] (In formula (4), n is in the range of 0 to 8, and R independently represents alkyl groups with 1 to 3 carbon atoms.)

[0026] <2> according to <1> The polycarbonate resin wherein the weight-average molecular weight Mw is 10,000 to 60,000.

[0027] <3> according to <1> or <2> The polycarbonate resin wherein the repeating units represented by the formula (3) in all repeating units of the resin exceed 0 mol% and are less than 50 mol%.

[0028] <4> according to <1> ~ <3> The polycarbonate resin according to any one of the following methods, wherein the repeating unit represented by the formula (4) in all repeating units of the resin is more than 0 mol% and less than 40 mol%.

[0029] <5> according to <1> ~ <4> The polycarbonate resin described in any one of the following statements, wherein R in formula (3) 1 ~R 4 It is a hydrogen atom.

[0030] <6> according to <1> ~ <5> The polycarbonate resin described in any one of the following statements, wherein the repeating unit of the formula (4) is a repeating unit derived from bisphenol TMC.

[0031] <7> according to <1> ~ <6> The polycarbonate resin described in any one of the following examples, wherein the absolute value of the oriented birefringence is 10.0 × 10⁻⁶. -3 the following.

[0032] <8> according to <1> ~ <7> The polycarbonate resin described in any one of the above examples, wherein the photoelastic modulus is less than 25 × 10⁻⁶. - 12 Pa.

[0033] <9> according to <1> ~ <8> The polycarbonate resin described in any one of the following examples has an Abbe number of 25.0 or higher.

[0034] <10> An optical component, made of <1> ~ <9> It is composed of the polycarbonate resin described in any one of the above.

[0035] <11> according to <10> The optical component is a camera lens.

[0036] The second approach disclosed herein includes the following schemes.

[0037] <1> A polycarbonate resin comprising repeating units represented by formula (1) and / or formula (2), repeating units represented by formula (3), and repeating units represented by formula (4), wherein the total of repeating units represented by formula (1) and / or formula (2) in all repeating units of the resin exceeds 0 mol% and is less than 50 mol%, and the weight-average molecular weight Mw of the polycarbonate resin is 10,000 or more.

[0038]

[0039]

[0040]

[0041] (where R) 1 ~R 4 Each can independently represent a hydrogen atom or a hydrocarbon group with 1 to 10 carbon atoms.

[0042]

[0043] (In formula (4), n is in the range of 0 to 8, and R independently represents alkyl groups with 1 to 3 carbon atoms.)

[0044] <2> according to <1> The polycarbonate resin wherein the weight-average molecular weight Mw is 10,000 to 60,000.

[0045] <3> according to <1> or <2> The polycarbonate resin wherein the repeating unit represented by the formula (3) in all repeating units of the resin is 10 mol% to 95 mol.

[0046] <4> according to <1> ~ <3> The polycarbonate resin according to any one of the following methods, wherein the repeating unit represented by the formula (4) in all repeating units of the resin is more than 0 mol% and less than 45 mol%.

[0047] <5> according to <1> ~ <4> The polycarbonate resin described in any one of the following statements, wherein R in formula (3) 1 ~R 4 It is a hydrogen atom.

[0048] <6> according to <1> ~ <5> The polycarbonate resin described in any one of the following statements, wherein the repeating unit of the formula (4) is a repeating unit derived from bisphenol TMC.

[0049] <7> according to <1> ~ <6> The polycarbonate resin described in any one of the following examples, wherein the absolute value of the oriented birefringence is 10.0 × 10⁻⁶. -3 the following.

[0050] <8> according to <1> ~ <7> The polycarbonate resin described in any one of the above statements, wherein the photoelastic modulus is 40 × 10⁻⁶. -12 Below Pa.

[0051] <9> according to <1> ~ <8> The polycarbonate resin described in any one of the following examples, wherein the refractive index nd is 1.550 or higher.

[0052] <10> according to <1> ~ <9> The polycarbonate resin described in any one of the following examples has a glass transition temperature of 140°C or higher.

[0053] <11> An optical component, made of <1> ~ <10> It is composed of the polycarbonate resin described in any one of the above.

[0054] <12> according to <11> The optical component is a camera lens.

[0055] The polycarbonate resin of the first embodiment disclosed herein has excellent balance between refractive index and Abbe number, resulting in oriented birefringence and low photoelasticity, thus achieving particularly significant industrial benefits.

[0056] The polycarbonate resin of the second aspect of this disclosure has particularly significant industrial benefits due to its low orientation birefringence, high refractive index, and high glass transition temperature. Attached Figure Description

[0057] Figure 1 The relationship between the refractive index and Abbe number of the thermoplastic resin and existing resin of the first embodiment of this disclosure is shown.

[0058] Figure 2 The relationship between the refractive index and Abbe number of the thermoplastic resin and existing resin of the second aspect of this disclosure is shown. Detailed Implementation

[0059] The embodiments of this disclosure will now be described. These descriptions and examples are illustrative and not intended to limit the scope of the embodiments. It should be noted that, unless otherwise specified, matters described in the form of "this disclosure" or "in this disclosure" are common to both the first and second embodiments.

[0060] In this disclosure, the numerical range represented by “~” indicates the range containing the minimum and maximum values ​​recorded before and after “~”, respectively.

[0061] In the numerical ranges described in this disclosure, the upper or lower limit of one numerical range can be replaced by the upper or lower limit of another numerical range described in other stages. Furthermore, the upper or lower limit of a numerical range described in this disclosure can be replaced by the values ​​shown in the embodiments.

[0062] <The polycarbonate resin disclosed herein>

[0063] The polycarbonate resin of the first aspect of this disclosure comprises repeating units represented by formula (1) and / or formula (2), repeating units represented by formula (3), and repeating units represented by formula (4), wherein the total of repeating units represented by formula (1) and / or formula (2) in all repeating units of the resin is 50 mol% or more.

[0064] The polycarbonate resin of the second aspect of this disclosure comprises repeating units represented by formula (1) and / or formula (2), repeating units represented by formula (3), and repeating units represented by formula (4), wherein the total of repeating units represented by formula (1) and / or formula (2) in all repeating units of the resin exceeds 0 mol% and is less than 50 mol%.

[0065] It should be noted that in this disclosure, the mol% mentioned above refers to the total of repeating units represented by formula (1) and / or formula (2), which means the total unit of formula (1) and formula (2) when the polycarbonate resin contains units represented by formula (1) and formula (2), and which means any unit contained when either formula (1) or formula (2) is contained.

[0066]

[0067]

[0068]

[0069] (where R) 1 ~R 4 Each can independently represent a hydrogen atom or a hydrocarbon group with 1 to 10 carbon atoms.

[0070]

[0071] (In formula (4), n is in the range of 0 to 8, and R independently represents alkyl groups with 1 to 3 carbon atoms.)

[0072] (weight-average molecular weight)

[0073] The polycarbonate resin of the first aspect of this disclosure has a weight-average molecular weight (Mw) of 10,000 or more, preferably 15,000 or more, and more preferably 20,000 or more. A weight-average molecular weight (Mw) of 10,000 or more provides sufficient mechanical strength for use as a structural or optical material, and is therefore preferred. Furthermore, a weight-average molecular weight (Mw) of 60,000 or less is preferred, more preferably 55,000 or less, further preferably 50,000 or less, and particularly preferably 45,000 or less. A weight-average molecular weight (Mw) of 60,000 or less provides excellent flowability during injection molding, and is therefore preferred. In particular, the polycarbonate resin of the first aspect of this disclosure exhibits excellent flowability when used in thin-walled optical components such as camera lenses, and is therefore preferred.

[0074] The polycarbonate resin of the second aspect of this disclosure has a weight-average molecular weight (Mw) of 10,000 or more, preferably 15,000 or more, and more preferably 20,000 or more. A weight-average molecular weight (Mw) of 10,000 or more provides sufficient mechanical strength for use as a structural or optical material, and is therefore preferred. Furthermore, a weight-average molecular weight (Mw) of 60,000 or less is preferred, more preferably 50,000 or less, even more preferably 40,000 or less, and even more preferably 30,000 or less. A weight-average molecular weight (Mw) of 60,000 or less provides excellent flowability during injection molding, and is therefore preferred. In particular, the polycarbonate resin of the second aspect of this disclosure exhibits excellent flowability when used in thin-walled optical components such as camera lenses, and is therefore preferred.

[0075] In this disclosure, the weight-average molecular weight Mw can be determined using polystyrene with a known molecular weight as a standard sample, chloroform as the developing solvent, and GPC.

[0076] (Absolute value of orientation birefringence)

[0077] The absolute value of the orientation birefringence of the polycarbonate resin in the first embodiment of this disclosure is preferably 10.0 × 10⁻⁶. -3 The following is more preferably 9.0×10 -3 The preferred value is 8.0×10. -3 The following is a further preferred value: 7.0 × 10 -3 The following is particularly preferred: 6.0 × 10 -3 The following is a further preferred value: 5.0 × 10 -3 The preferred value is 4.0 × 10⁻⁶. -3 Below. When the absolute value of oriented birefringence is below the above-mentioned value, birefringence is less likely to occur due to molecular orientation, and therefore is preferred.

[0078] The absolute value of the orientation birefringence of the polycarbonate resin in the second aspect of this disclosure is preferably 10.0 × 10⁻⁶. -3 The following is more preferably 8.5×10 -3 The preferred value is 5.5×10. -3 Hereinafter, 3.0 × 10 is further preferred. -3 The following is a further preferred value: 1.5 × 10⁻⁶ -3 The following is particularly preferred: 1.0 × 10 -3 The optimal value is 0.5 × 10⁻⁶. -3 Below. When the absolute value of oriented birefringence is below the above-mentioned value, birefringence is less likely to occur due to molecular orientation, and therefore is preferred.

[0079] In this disclosure, orientation birefringence is measured by cutting a 70 mm long (45 mm between fixtures) and 15 mm wide test piece from a 100 μm thick cast film made of polycarbonate resin, subjecting it to a 2x stretch at Tg+10°C, and then measuring it at a wavelength of 589 nm.

[0080] (Photoelastic coefficient)

[0081] The photoelasticity of the polycarbonate resin of the first aspect of this disclosure is preferably less than 25 × 10⁻⁶. -12 Pa, more preferably 20 × 10 Pa -12 Pa is below 16×10 Pa, and 16×10 Pa is more preferred. -12 Pa or less, more preferably 12 × 10 Pa -12 Below Pa. When the photoelastic coefficient is within the above range, birefringence is less likely to occur due to stress, and therefore it is preferred.

[0082] The photoelasticity of the polycarbonate resin of the second aspect of this disclosure is preferably less than 40 × 10⁻⁶. -12 Pa, more preferably 35 × 10 Pa -12 Below Pa, 30×10 is more preferred. -12 Pa or less, more preferably 25 × 10 Pa -12 Below Pa. When the photoelastic coefficient is within the above range, stress-induced birefringence is less likely to occur, and therefore it is preferred.

[0083] In this disclosure, the photoelasticity coefficient was measured using a Spectroellipsometer M-220 manufactured by Nippon Spectrophotometer Co., Ltd., by cutting test pieces 50 mm long and 10 mm wide from a 100 μm thick cast film made of polycarbonate resin.

[0084] (Refractive index)

[0085] The polycarbonate resin of the first aspect of this disclosure has a refractive index nd of 1.540 or higher, more preferably 1.550 or higher, even more preferably 1.560 or higher, even more preferably 1.570 or higher, and particularly preferably 1.575 or higher, as measured at a temperature of 20°C and a wavelength of 587.56 nm. A refractive index of nd of 1.610 or lower allows for thinner optical components, which is therefore preferred. Alternatively, the refractive index nd can be 1.610 or lower, 1.600 or lower, 1.590 or lower, or 1.580 or lower. A refractive index nd within the above range increases the freedom of optical design in terms of combining multiple lenses, which is also preferred.

[0086] The refractive index nd of the polycarbonate resin of the second aspect of this disclosure, measured at a temperature of 20°C and a wavelength of 587.56 nm, is preferably 1.550 or higher, more preferably 1.575 or higher, even more preferably 1.600 or higher, further preferably 1.610 or higher, and particularly preferably 1.620 or higher. When the refractive index nd is within the above range, the optical component can be made thinner, which is therefore preferred. Alternatively, the refractive index nd can also be 1.650 or lower, 1.645 or lower, 1.640 or lower, or 1.635 or lower. When the refractive index nd is within the above range, the degree of freedom in optical design is increased in terms of combining multiple lenses, which is therefore preferred.

[0087] In this disclosure, the refractive index nd (587.56 nm) was measured using a Shimadzu KALNEW precision refractometer KPR-2000.

[0088] (Abbe number)

[0089] The Abbe number of the polycarbonate resin of the first aspect of this disclosure is preferably 25.0 or higher, more preferably 30.0 or higher, even more preferably 32.0 or higher, further preferably 37.0 or higher, particularly preferably 42.0 or higher, and most preferably 46.0 or higher. When the Abbe number is above the above, the chromatic aberration of the optical component is reduced, and therefore preferred. Alternatively, the Abbe number may be 57.0 or lower, 55.0 or lower, 50.0 or lower, or 47.0 or lower. When the Abbe number is within the above range, the degree of freedom in optical design is increased in terms of combining multiple lenses, and therefore preferred.

[0090] The Abbe number of the polycarbonate resin in the second aspect of this disclosure is preferably 23.0 or higher, more preferably 25.0 or higher, even more preferably 27.0 or higher, further preferably 30.0 or higher, and even more preferably 32.0 or higher. When the Abbe number is within the above range, the chromatic aberration of the optical components is reduced, and therefore it is preferred. Alternatively, the Abbe number may be 35.0 or lower, or 34.0 or lower. When the Abbe number is within the above range, the degree of freedom in optical design is increased in terms of combining multiple lenses, and therefore it is preferred.

[0091] Here, the Abbe number (νd) of this disclosure is calculated using the following formula based on the refractive index at a temperature of 20°C and wavelengths of 486.13 nm, 587.56 nm, and 656.27 nm.

[0092] νd=(nd-1) / (nF-nC)

[0093] nd represents the refractive index at a wavelength of 587.56 nm.

[0094] nF represents the refractive index at a wavelength of 486.13 nm.

[0095] nC represents the refractive index at a wavelength of 656.27 nm.

[0096] The refractive index and Abbe number of the polycarbonate resin disclosed herein preferably satisfy the following mathematical formula (A).

[0097] nd ≥ -0.0063×νd+α (A)

[0098] In the first aspect of this disclosure, α in mathematical formula (A) is preferably 1.767 or higher, more preferably 1.770 or higher, even more preferably 1.773 or higher, further preferably 1.776 or higher, and most preferably 1.779 or higher.

[0099] The preferred value is nd > 1.535.

[0100] On the other hand, in the second aspect of this disclosure, α in mathematical formula (A) is preferably 1.768 or more, more preferably 1.770 or more, even more preferably 1.772 or more, further preferably 1.775 or more, and most preferably 1.777 or more.

[0101] The preferred value is nd > 1.535.

[0102] The refractive index and Abbe number of the polycarbonate resin of the first aspect of this disclosure can also satisfy the following mathematical formula (B).

[0103] nd ≤ -0.0023×νd+β (B)

[0104] In mathematical formula (B), β can also be 1.675 or less, 1.673 or less, 1.671 or less, 1.669 or less, or 1.666 or less. When the refractive index and Abbe number are within the above ranges, the Abbe number relative to the refractive index is higher, which expands the range of optical designs and is therefore preferred.

[0105] On the other hand, the refractive index and Abbe number of the polycarbonate resin of the second aspect of this disclosure can also satisfy the following mathematical formula (B').

[0106] nd ≤ -0.0057×νd+β (B')

[0107] The β in the mathematical formula (B') can also be less than 1.782, less than 1.780, less than 1.778, less than 1.776, or less than 1.773. When the refractive index and Abbe number are within the above ranges, the Abbe number relative to the refractive index is higher, which expands the range of optical designs and is therefore preferred.

[0108] (Glass transition temperature)

[0109] The glass transition temperature of the polycarbonate resin of the first aspect of this disclosure is preferably 130°C or higher, more preferably 133°C or higher, and even more preferably 136°C or higher. When the glass transition temperature is within the above range, the usable temperature range of the optical component becomes higher, which is therefore preferred. Alternatively, the glass transition temperature may also be 155°C or lower, 150°C or lower, 145°C or lower, or 140°C or lower. When the glass transition temperature is within the above range, the balance between heat resistance and moldability is excellent, which is therefore preferred.

[0110] The glass transition temperature of the polycarbonate resin in the second aspect of this disclosure is preferably 140°C or higher, more preferably 142°C or higher, even more preferably 144°C or higher, further preferably 146°C or higher, and even more preferably 148°C or higher. When the glass transition temperature is within the above range, the usable temperature range of the optical component becomes higher, and therefore it is preferred. Alternatively, the glass transition temperature may also be 160°C or lower, 157°C or lower, or 154°C or lower. When the glass transition temperature is within the above range, the balance between heat resistance and moldability is excellent, and therefore it is preferred.

[0111] In this disclosure, the glass transition temperature of polycarbonate resin was determined using a DiscoveryDSC 25Auto differential scanning calorimeter manufactured by TA Instruments Japan Co., Ltd. at a heating rate of 20°C / min.

[0112] (Thermal decomposition temperature)

[0113] The thermal decomposition temperature of the polycarbonate resin of the first aspect of this disclosure is preferably 370°C or higher, more preferably 374°C or higher. When the thermal decomposition temperature is above or higher, the processing stability of the polycarbonate resin of the first aspect of this disclosure is excellent during molding, resulting in less coloring, and is therefore preferred. Alternatively, the thermal decomposition temperature may also be 420°C or lower, or 400°C or lower.

[0114] The polycarbonate resin of the second aspect of this disclosure preferably has a thermal decomposition temperature of 370°C or higher, more preferably 375°C or higher, and even more preferably 380°C or higher. When the thermal decomposition temperature is above the aforementioned levels, the polycarbonate resin of the second aspect of this disclosure exhibits excellent processing stability during molding and processing, resulting in less coloring, and is therefore preferred. Alternatively, the thermal decomposition temperature may also be 420°C or lower, or 400°C or lower.

[0115] In this disclosure, the thermal decomposition temperature can be determined by TGA (thermogravimetric analysis), and is the temperature at which the weight decreases by 5%.

[0116] (Specific viscosity)

[0117] The specific viscosity of the polycarbonate resin of the first embodiment of this disclosure is preferably 0.12 to 0.32, more preferably 0.18 to 0.30. When the specific viscosity is within the above range, the balance between moldability and strength is excellent.

[0118] The specific viscosity of the polycarbonate resin of the second aspect of this disclosure is preferably 0.12 to 0.32, more preferably 0.18 to 0.30. When the specific viscosity is within the above range, the balance between moldability and strength is excellent.

[0119] The method for determining the specific viscosity in this disclosure is as follows: the specific viscosity (ηSP) of a solution obtained by dissolving 0.7 g of polycarbonate resin in 100 ml of dichloromethane at 20 °C is measured using an Auster viscometer, and calculated according to the following formula.

[0120] ηSP=(t-t0) / t0

[0121] [t0 is the number of seconds it takes for dichloromethane to fall, and t is the number of seconds it takes for the sample solution to fall.]

[0122] (Partial Dispersion Ratio)

[0123] The partial dispersion ratio (θgF) of the polycarbonate resin from the g line to the F line in the first aspect of this disclosure is preferably 0.62 or less, more preferably 0.61 or less, even more preferably 0.60 or less, further preferably 0.59 or less, and most preferably 0.58 or less. When θgF is below the above-mentioned values, the range of optical designs is expanded, and therefore it is preferred.

[0124] The partial dispersion ratio (θgF) of the polycarbonate resin from the g line to the F line in the second aspect of this disclosure is preferably 0.64 or less, more preferably 0.63 or less, even more preferably 0.62 or less, further preferably 0.61 or less, and most preferably 0.59 or less. When θgF is below the above-mentioned values, the range of optical designs is expanded, and therefore it is preferred.

[0125] Here, the partial dispersion ratio (θgF) from the g line to the F line in this disclosure is calculated using the following formula based on the refractive index at wavelengths of 435.83 nm, 587.56 nm, and 656.27 nm at a temperature of 20 °C.

[0126] θgF=(ng-nF) / (nF-nC)

[0127] ng represents the refractive index at a wavelength of 435.83 nm.

[0128] nF represents the refractive index at a wavelength of 486.13 nm.

[0129] nC represents the refractive index at a wavelength of 656.27 nm.

[0130] (Equation (3))

[0131] In the polycarbonate resin disclosed herein, R in formula (3) above 1 ~R 4 Each group can independently represent a hydrocarbon group with 1 to 10 hydrogen or carbon atoms. Examples of hydrocarbon groups include alkyl, cycloalkyl, and aryl groups.

[0132] Examples of alkyl groups include methyl, ethyl, propyl, isopropyl, butyl, tert-butyl, etc., with methyl and ethyl being preferred.

[0133] Examples of cycloalkyl groups include cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, and bicyclo[1.1.1]pentyl.

[0134] Examples of aryl groups include phenyl, tolyl, naphthyl, and xylyl, with phenyl being the preferred group.

[0135] R 1 ~R 4 Each is preferably a hydrogen atom, methyl group, or phenyl group, more preferably a hydrogen atom or phenyl group, R 1 and R 2 Each is independently a hydrogen atom or a phenyl group and R 3 and R 4 When the aliphatic ring is hydrogen, the volume occupied by the aliphatic ring in space increases, which can reduce the photoelastic coefficient, thus making it a further preferred option.

[0136] The repeating unit represented by formula (3) above is preferably a repeating unit derived from 9,9-bis[4-(2-hydroxyethoxy)phenyl]fluorene or 9,9-bis[4-(2-hydroxyethoxy)-3-phenylphenyl]fluorene. When the repeating unit is derived from 9,9-bis[4-(2-hydroxyethoxy)phenyl]fluorene, the orientation birefringence and photoelasticity coefficient are low, which is more preferred for the polycarbonate resin of the first aspect of this disclosure. In addition, from the viewpoint of low orientation birefringence, it is also more preferred for the polycarbonate resin of the second aspect of this disclosure.

[0137] (Equation (4))

[0138] In the polycarbonate resin disclosed herein, in the above formula (4), n is in the range of 0 to 8, preferably 0 to 5 or 1 to 3, and in particular, when it is 3, the glass transition temperature is high, and therefore preferred.

[0139] In addition, R is selected from alkyl groups having 1 to 3 carbon atoms, preferably methyl or ethyl, especially methyl, which has a high glass transition temperature and is therefore preferred.

[0140] Furthermore, it is particularly preferred that the repeating unit of the above formula (4) is a repeating unit derived from 4,4'-(3,3,5-trimethylcyclohexylidene) bisphenol (so-called bisphenol TMC), 4,4'-cyclohexylidene bisphenol (so-called bisphenol Z), or 4,4'-(3-methylcyclohexylidene) bisphenol (so-called bisphenol 3MZ), wherein the repeating unit derived from bisphenol TMC is preferred because it can increase the glass transition temperature.

[0141] (Equation (1) and Equation (2))

[0142] In the polycarbonate resin disclosed herein, the repeating unit represented by formula (1) and / or formula (2) above is a repeating unit derived from pentacyclopentadecanedimethanol. In formula (1) and / or formula (2) above, it can be either a pure substance or a mixture of various isomers mixed in any proportion. It should be noted that pentacyclopentadecanedimethanol comprises the following structural formula.

[0143]

[0144]

[0145] (Other repeating units)

[0146] The polycarbonate resin disclosed herein may contain repeating units other than those represented by formulas (1) to (4) above, to a extent that does not impair the advantageous effects of the present disclosure. Examples of dihydroxy compounds that introduce such repeating units include ethylene glycol, propylene glycol, butanediol, pentanediol, hexanediol, heptahydrol, octanediol, nonanediol, and tricyclic [5.2.1.0] 2,6 Decanediethanol, Cyclohexane-1,4-diethanol, Naphthane-2,6-diethanol, Norbornenediethanol, Cyclopentane-1,3-diethanol, Isosorbide, Isomannitol, Isodi-Idoutitol, Hydroquinone, Resorcinol, 2,2-Bis(4-hydroxyphenyl)propane, 2,2-Bis(3-methyl-4-hydroxyphenyl)propane, 1,1-Bis(4-hydroxyphenyl)-1-phenylethane, Bis(4-hydroxyphenyl)diphenylmethane, 1,3-Bis(2-(4-hydroxyphenyl)-2-propyl)benzene, 4,4'-(3,3,5-trimethylcyclohexylidene)bisphenol, 4,4'-cyclohexylidene bisphenol, 4,4'-(3-methylcyclohexylidene)bisphenol, bis(4-hydroxyphenyl) sulfone, bis(4-hydroxyphenyl) sulfide, biphenol, bisphenol fluorene, biscresol fluorene, 1,1'-bi-2-naphthol, 2,2'-bis(2-hydroxyethoxy)-1,1'-binaphthol, etc. This type of repeating unit can also be less than 30 mol% in all repeating units.

[0147] (Repeating unit quantity)

[0148] The total number of repeating units represented by the above formulas (1) to (4) of the polycarbonate resin disclosed herein is preferably 70 mol% or more, more preferably 80 mol% or more, and even more preferably 90 mol% or more.

[0149] In the polycarbonate resin of the first aspect of this disclosure, the total number of repeating units represented by the above formula (1) or / and formula (2) in all repeating units of the resin is 50 mol% or more, more preferably 55 mol% or more, and if it is 60 mol% or more, the Abbe number is high and it is further preferred.

[0150] In the polycarbonate resin of the first aspect of this disclosure, the repeating units represented by the above formula (3) in all repeating units of the resin can exceed 0 mol%, 2 mol% or more, 8 mol% or more, 12 mol% or more, 15 mol% or more, 20 mol% or more, 25 mol% or more, 30 mol% or more, 33 mol% or more, 37 mol% or more, or can be less than 50 mol%, less than 45 mol%, less than 38 mol%, less than 25 mol%, less than 16 mol% or less, or less than 10 mol%. The repeating units are preferably more than 0 mol% and less than 50 mol%, more preferably 2 to 45 mol%, and are further preferred if they are 2 to 40 mol%, as the orientation birefringence is lower.

[0151] In the polycarbonate resin of the first aspect of this disclosure, the repeating units represented by the above formula (4) in all repeating units of the resin can exceed 0 mol%, 2 mol% or more, 3 mol% or more, 5 mol% or more, 8 mol% or more, 10 mol% or more, 15 mol% or more, 20 mol% or more, 25 mol% or more, or can be less than 40 mol%, less than 35 mol%, less than 30 mol%, less than 25 mol%, or less than 20 mol%. The repeating units are preferably more than 0 mol% and less than 40 mol%, more preferably 2 to 35 mol%, and even more preferably 3 to 30 mol%, as the glass transition temperature is high.

[0152] In the polycarbonate resin of the second aspect of this disclosure, the total amount of repeating units represented by the above formula (1) or / and formula (2) in all repeating units of the resin exceeds 0 mol%, and can be 2 mol% or more, 8 mol% or more, 12 mol% or more, 15 mol% or more, 20 mol% or more, 25 mol% or more, 30 mol% or more, 33 mol% or more, 37 mol% or more, 40 mol% or more, 45 mol% or more, and is less than 50 mol%, and can be less than 45 mol% or less, 38 mol% or less, 25 mol% or less, 16 mol% or less, 10 mol% or less. The repeating units exceeding 0 mol% and less than 50 mol% are preferably 2 mol% to 45 mol%. If they are 2 mol% to 40 mol%, the Abbe number is high, the photoelastic coefficient is low, and the balance between orientation birefringence, refractive index and glass transition temperature is excellent, which is more preferable.

[0153] In the polycarbonate resin of the second aspect of this disclosure, the total of the repeating units represented by the above formula (3) in all repeating units of the resin can be 10 mol% or more, 15 mol% or more, 20 mol% or more, 30 mol% or more, 35 mol% or more, 40 mol% or more, 45 mol% or more, 50 mol% or more, 60 mol% or more, 70 mol% or more, 80 mol% or more, or 90 mol% or more, or it can be 95 mol% or less, 80 mol% or less, 50 mol% or less, 45 mol% or less, 30 mol% or less, or 20 mol% or less. The repeating units are preferably 10 mol% to 95 mol%, more preferably 12 mol% to 94 mol%, and if they are 15 mol% to 93 mol%, the orientation birefringence is low, which is even more preferred.

[0154] In the polycarbonate resin of the second aspect of this disclosure, the repeating units represented by the above formula (4) in all repeating units of the resin can be more than 0 mol%, more than 2 mol%, more than 3 mol%, more than 5 mol%, more than 8 mol%, more than 10 mol%, more than 15 mol%, more than 20 mol%, more than 25 mol%, more than 30 mol%, more than 35 mol%, or less than 45 mol%, less than 40 mol%, less than 30 mol%, less than 25 mol%, or less than 20 mol%. The repeating units are preferably more than 0 mol% and less than 45 mol%, more preferably 2 mol% to 43 mol%, and if they are 3 mol% to 40 mol%, the glass transition temperature is high, and therefore it is even more preferred.

[0155] (Terminal phenolic hydroxyl group)

[0156] The polycarbonate resin disclosed herein preferably does not have phenolic hydroxyl groups at the ends. That is, when a monomer with a repeating unit introduced into it as shown in formula (4) above is polymerized and attached to the ends, the end groups become phenolic hydroxyl groups. Therefore, for example, it is preferable to reduce the amount of phenolic hydroxyl groups at the ends of the polycarbonate resin by using an excess of diester carbonate relative to the dihydroxy compound used as a raw material during polymerization to convert the ends to phenyl groups.

[0157] The ratio of terminal phenolic hydroxyl groups can be determined by the following method.

[0158] The ratio of terminal phenolic hydroxyl groups = (amount of terminal phenolic hydroxyl groups / total amount of terminal hydroxyl groups) × 100

[0159] It should be noted that all the terminals consist of terminal phenolic hydroxyl groups, terminal alcoholic hydroxyl groups, and terminal phenyl groups.

[0160] Specifically, the ratio of terminal phenolic hydroxyl groups can be determined by the following methods, but is not limited to this example.

[0161] (1) Through polycarbonate resin 1 H NMR measurements were used to observe the terminal phenolic hydroxyl groups, and the integral of the corresponding peak was obtained and set to 1. At this time, the integral intensity (A) of one proton of the fluorene structure was calculated based on the integral intensity of the peaks at positions 4 and 5 of the fluorene structure from the above formula (3). When no peak of the terminal phenolic hydroxyl group was observed, the ratio of terminal phenolic hydroxyl groups was 0.

[0162] (2) Based on the average molecular weight of the polycarbonate resin obtained by GPC and the molecular weight and molar ratio of each repeating unit, the average degree of polymerization of the polycarbonate resin is calculated. Based on the mol% and integral intensity (A) of the above formula (3), the end-capacity is calculated using the following formula. 1 Integral intensity (B) in H NMR spectrum.

[0163] (B) = (A) × 100 × 2 / ([mol% of the above formula (3)] × average degree of polymerization)

[0164] (3) The ratio of terminal phenolic hydroxyl groups is calculated as 1 / (B)×100.

[0165] The polycarbonate resin disclosed herein preferably has a terminal phenolic hydroxyl group ratio of 30% or less, 20% or less, 15% or less, 10% or less, 5% or less, 3% or less, 1% or less, or 0.5% or less to suppress color changes caused by damp heat, and is therefore preferred.

[0166] (Total light transmittance)

[0167] The total light transmittance of the 1 mm thick polycarbonate resin molded body disclosed herein is preferably 80% or more, more preferably 85% or more, and particularly preferably 88% or more. The 1 mm thick molded body can be obtained by injection molding, hot pressing, melt extrusion molding, or other methods using the polycarbonate resin disclosed herein.

[0168] In this disclosure, the total light transmittance can be achieved using colors manufactured by Nippon Denshoku Kogyo Co., Ltd. Turbidity was measured using a COH 400 turbidity meter (D65 light source, 10° field of view).

[0169] (Saturated water absorption rate)

[0170] The saturated water absorption rate of the polycarbonate resin disclosed herein can be 0.10%–0.70%, 0.20%–0.70%, or 0.30%–0.65%.

[0171] In this disclosure, the saturated water absorption rate is calculated by measuring the weight change of a 50mm×40mm×2mm test piece immersed in water at 23°C, according to the following formula.

[0172] Saturated water absorption rate (%) = (W s -W0)×100 / W0

[0173] W0: Weight of the test piece after drying at 50°C for 48 hours and cooling in a desiccator for 1 hour.

[0174] W s The weight of the test piece when it is immersed in water and the weight change reaches saturation.

[0175] <Manufacturing Method of Polycarbonate Resin>

[0176] The polycarbonate resin disclosed herein can be manufactured by reaction methods known in the conventional manufacture of polycarbonate resins, such as reacting carbonate precursors like diesters with dihydroxy compounds. The basic means of these manufacturing methods will now be briefly described.

[0177] Transesterification using diester as a carbonate precursor is carried out by heating and stirring a predetermined proportion of dihydroxy components with diester under an inert gas atmosphere, followed by distillation of the resulting alcohol or phenol. The reaction temperature varies depending on the boiling point of the alcohol or phenol produced, typically ranging from 120 to 300°C. The reaction begins with vacuum distillation of the resulting alcohol or phenol to complete the reaction. Additionally, end-capping agents, antioxidants, etc., can be added as needed.

[0178] Examples of diesters used in the transesterification reaction include esters of aryl and aralkyl groups with 6 to 12 substituted carbon atoms. Specifically, examples include diphenyl carbonate, xylene carbonate, bis(chlorophenyl) carbonate, and m-toluene carbonate. Diphenyl carbonate is particularly preferred. The amount of diphenyl carbonate used is preferably 0.95 to 1.10 mol relative to 1 mol of the total dihydroxy compound, more preferably 0.98 to 1.04 mol.

[0179] In addition, in melt polymerization, polymerization catalysts can be used to accelerate the polymerization rate. Examples of such polymerization catalysts include alkali metal compounds, alkaline earth metal compounds, and nitrogen-containing compounds.

[0180] As such compounds, organic acid salts, inorganic salts, oxides, hydroxides, hydrides, alkoxides, quaternary ammonium hydroxides, etc., of alkali metals and alkaline earth metals are preferred. These compounds can be used alone or in combination.

[0181] Examples of alkali metal compounds include sodium hydroxide, potassium hydroxide, cesium hydroxide, lithium hydroxide, sodium bicarbonate, sodium carbonate, potassium carbonate, cesium carbonate, lithium carbonate, sodium acetate, potassium acetate, cesium acetate, lithium acetate, sodium stearate, potassium stearate, cesium stearate, lithium stearate, sodium borohydride, sodium benzoate, potassium benzoate, cesium benzoate, lithium benzoate, disodium hydrogen phosphate, dipotassium hydrogen phosphate, dilithium hydrogen phosphate, disodium phenyl phosphate, disodium salt of bisphenol A, dipotassium salt of bisphenol A, dicesium salt of bisphenol A, dilithium salt of bisphenol A, sodium salt of phenol, potassium salt of phenol, cesium salt of phenol, and lithium salt of phenol.

[0182] Examples of alkaline earth metal compounds include magnesium hydroxide, calcium hydroxide, strontium hydroxide, barium hydroxide, magnesium carbonate, calcium carbonate, strontium carbonate, barium carbonate, magnesium diacetate, calcium diacetate, strontium diacetate, and barium diacetate.

[0183] Examples of nitrogen-containing compounds include quaternary ammonium hydroxides containing alkyl or aryl groups, such as tetramethylammonium hydroxide, tetraethylammonium hydroxide, tetrapropylammonium hydroxide, tetrabutylammonium hydroxide, and trimethylbenzylammonium hydroxide. Examples of bases or basic salts include tetramethylammonium borohydride, tetrabutylammonium borohydride, tetrabutylammonium tetraphenylborate, and tetraphenylammonium tetraphenylborate.

[0184] Other transesterification catalysts include salts of zinc, tin, zirconium, lead, titanium, germanium, antimony, and osmium, such as zinc acetate, zinc benzoate, zinc 2-ethylhexanoate, tin(II) chloride, tin(IV) chloride, tin(II) acetate, tin(IV) acetate, dibutyltin dilaurate, dibutyltin oxide, dibutyldimethoxytin, zirconium acetylacetonate, zirconium glycolate, tetrabutoxyzirconium, lead(II) acetate, lead(IV) acetate, and tetrabutoxytitanium(IV). Catalysts used in International Patent Publication No. 2011 / 010741 and Japanese Patent Application Publication No. 2017-179323 can also be used.

[0185] Alternatively, a catalyst composed of aluminum or its compounds and a phosphorus compound can also be used. In this case, the concentration of the dihydroxyl content is preferably 80 μmol to 1000 μmol per mol, more preferably 90 μmol to 800 μmol, and even more preferably 100 μmol to 600 μmol per mol.

[0186] Examples of aluminum salts include organic and inorganic acid salts. Organic acid salts of aluminum include, for example, aluminum carboxylates, specifically aluminum formate, aluminum acetate, aluminum propionate, aluminum oxalate, aluminum acrylate, aluminum laurate, aluminum stearate, aluminum benzoate, aluminum trichloroacetate, aluminum lactate, aluminum citrate, and aluminum salicylate. Inorganic acid salts of aluminum include, for example, aluminum chloride, aluminum hydroxide, aluminum hydroxide chloride, aluminum carbonate, aluminum phosphate, and aluminum phosphonate. Aluminum chelates include, for example, aluminum acetylacetone, aluminum acetoacetate, aluminum ethyl acetoacetate, and aluminum di(isopropanol)acetoacetate.

[0187] Examples of phosphorus compounds include phosphonic acid compounds, phosphonium hypophosphonic acid compounds, phosphonium oxide compounds, phosphonium phosphonium compounds, phosphonium hypophosphonium compounds, and phosphonic compounds. Among these, phosphonic acid compounds, phosphonium hypophosphonic acid compounds, and phosphonium oxide compounds are particularly noteworthy, especially phosphonic acid compounds.

[0188] The amount of these polymerization catalysts relative to 1 mol of dihydroxyl content is preferably 0.1 μmol to 500 μmol, more preferably 0.5 μmol to 300 μmol, and even more preferably 1 μmol to 100 μmol.

[0189] Alternatively, a catalyst deactivator can be added in the later stages of the reaction. Known catalyst deactivators can be used effectively, with ammonium salts of sulfonic acid being preferred. Salt. Tetrabutyl dodecylbenzenesulfonate is further preferred. Salts of dodecylbenzenesulfonic acid, such as sodium sulfonate; salts of p-toluenesulfonic acid, such as tetrabutylammonium p-toluenesulfonate.

[0190] Furthermore, methyl benzenesulfonate, ethyl benzenesulfonate, butyl benzenesulfonate, octyl benzenesulfonate, phenyl benzenesulfonate, methyl p-toluenesulfonate, ethyl p-toluenesulfonate, butyl p-toluenesulfonate, octyl p-toluenesulfonate, and phenyl p-toluenesulfonate are preferred as esters of sulfonic acids. Among these, tetrabutyl dodecylbenzenesulfonate is the most preferred. Salt.

[0191] When using at least one polymerization catalyst selected from alkali metal compounds and / or alkaline earth metal compounds, the amount of these catalyst deactivators used relative to 1 mol of the catalyst is preferably 0.5 to 50 mol, more preferably 0.5 to 10 mol, and even more preferably 0.8 to 5 mol.

[0192] <Any Additives>

[0193] In the polycarbonate resin disclosed herein, mold release agents, heat stabilizers (also referred to as antioxidants as appropriate), ultraviolet absorbers, blue toners, antistatic agents, flame retardants, plasticizers, fillers, antioxidants, light stabilizers, polymeric metal deactivators, lubricants, surfactants, antibacterial agents, and other additives may be added as needed to use it as a resin composition. As specific mold release agents and heat stabilizers, those described in International Publication No. 2011 / 010741 are preferred examples.

[0194] As a particularly preferred release agent, a mixture of glyceryl monostearate, triglyceride stearate, pentaerythritol tetrastearate, triglyceride stearate, and stearyl stearate is preferably used. Furthermore, when the release agent is set to 100% by weight, the amount of the esters in the release agent is preferably 90% by weight or more, more preferably 95% by weight or more. Additionally, relative to 100 parts by weight of polycarbonate resin, the content of the release agent is preferably in the range of 0.005 to 2.0 parts by weight, more preferably in the range of 0.01 to 0.6 parts by weight, and even more preferably in the range of 0.02 to 0.5 parts by weight.

[0195] Examples of heat stabilizers include phosphorus-based heat stabilizers, sulfur-based heat stabilizers, and hindered phenolic heat stabilizers.

[0196] In addition, particularly preferred phosphorus-based heat stabilizers include tris(2,4-di-tert-butylphenyl) phosphite, bis(2,6-di-tert-butyl-4-methylphenyl) pentaerythritol diphosphite, tetra(2,4-di-tert-butylphenyl)-4,4'-biphenyl diphosphite, distearate pentaerythritol diphosphite, bis(2,4-dicumylphenyl) pentaerythritol diphosphite, cyclic neopentanetetrayl bis(2,6-di-tert-butyl-4-methylphenyl) phosphite, and bis(2,4-di-tert-butylphenyl) pentaerythritol diphosphite. Furthermore, the content of the phosphorus-based heat stabilizer is preferably 0.001 to 0.2 parts by weight relative to 100 parts by weight of polycarbonate resin.

[0197] Furthermore, pentaerythritol-tetra(3-lauryl thiopropionate) is a particularly preferred sulfur-based heat stabilizer. Additionally, the content of the sulfur-based heat stabilizer is preferably 0.001 to 0.2 parts by weight relative to 100 parts by weight of polycarbonate resin.

[0198] In addition, preferred hindered phenolic heat stabilizers include octadecyl-3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate, pentaerythritol tetrakis[3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate], triethylene glycol bis[3-(3-tert-butyl-5-methyl-4-hydroxyphenyl)propionate], 1,6-hexanediol bis[3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate], and 1,3,5-trimethyl-2,4,6-tris( 3,5-Di-tert-butyl-4-hydroxybenzyl)benzene, N,N-hexamethylenebis(3,5-di-tert-butyl-4-hydroxy-hydrogenated cinnamamide), diethyl 3,5-di-tert-butyl-4-hydroxy-benzylphosphonate, tris(3,5-di-tert-butyl-4-hydroxybenzyl)isocyanurate, 3,9-bis{1,1-dimethyl-2-[β-(3-tert-butyl-4-hydroxy-5-methylphenyl)propionyloxy]ethyl}-2,4,8,10-tetraoxaspiro(5,5)undecane.

[0199] The content of hindered phenolic heat stabilizer is preferably 0.001 to 0.3 parts by weight relative to 100 parts by weight of polycarbonate resin.

[0200] Phosphorus-based heat stabilizers and hindered phenolic heat stabilizers can also be used together.

[0201] As a UV absorber, it is preferably selected from at least one UV absorber selected from benzotriazole UV absorbers, benzophenone UV absorbers, triazine UV absorbers, cyclic imino ester UV absorbers, and cyanoacrylate UV absorbers.

[0202] Among benzotriazole-based ultraviolet absorbers, 2-(2-hydroxy-5-tert-octylphenyl)benzotriazole and 2,2'-methylenebis[4-(1,1,3,3-tetramethylbutyl)-6-(2H-benzotriazole-2-yl)phenol] are more preferred.

[0203] Examples of benzophenone-based ultraviolet absorbers include 2-hydroxy-4-dodecyloxybenzophenone and 2-hydroxy-4-methoxy-2'-carboxybenzophenone.

[0204] Examples of triazine-based ultraviolet absorbers include 2-(4,6-diphenyl-1,3,5-triazin-2-yl)-5-[(hexyl)oxy]-phenol and 2-(4,6-bis(2,4-dimethylphenyl)-1,3,5-triazin-2-yl)-5-[(octyl)oxy]-phenol.

[0205] 2,2'-p-phenylenebis(3,1-benzo[a])2 is particularly preferred as a cyclic imino ester-based ultraviolet absorber. (azin-4-one).

[0206] Examples of cyanoacrylate-based ultraviolet absorbers include 1,3-bis-[(2'-cyano-3',3'-diphenylacryloyl)oxy]-2,2-bis{[(2-cyano-3,3-diphenylacryloyl)oxy]methyl}propane and 1,3-bis-[(2-cyano-3,3-diphenylacryloyl)oxy]benzene.

[0207] The amount of ultraviolet absorber is preferably 0.01 to 3.0 parts by weight relative to 100 parts by weight of polycarbonate resin. Within this range, sufficient weather resistance can be imparted to the molded polycarbonate resin according to the application.

[0208] <Optical Components>

[0209] The optical components disclosed herein include the aforementioned polycarbonate resin. Examples of such optical components are not particularly limited to any optical application useful to the aforementioned polycarbonate resin, including optical discs, transparent conductive substrates, optical cards, sheets, thin films, optical fibers, lenses, prisms, optical films, substrates, filters, hard-coated films, etc.

[0210] In addition, the optical components disclosed herein may be composed of a resin composition comprising the aforementioned polycarbonate resin, wherein the resin composition may be formulated with additives such as heat stabilizers, plasticizers, light stabilizers, polymeric metal deactivators, flame retardants, lubricants, antistatic agents, surfactants, antibacterial agents, ultraviolet absorbers, mold release agents, blue toners, fillers, and antioxidants as needed.

[0211] <Optical Lenses>

[0212] As an optical component disclosed herein, an optical lens is particularly noteworthy. Examples of such optical lenses include camera lenses for mobile phones, smartphones, tablets, personal computers, digital cameras, camcorders, vehicle cameras, surveillance cameras, and sensor cameras such as TOF cameras. It is especially useful for camera lenses.

[0213] When manufacturing the optical lens of this disclosure by injection molding, it is preferable to mold at a barrel temperature of 220–350°C and a mold temperature of 70–180°C. More preferably, molding is performed at a barrel temperature of 240–300°C and a mold temperature of 80–170°C. When the barrel temperature is above 350°C, the polycarbonate resin decomposes and colors; when it is below 230°C, the melt viscosity is high, making it difficult to mold. In addition, when the mold temperature is above 180°C, the molded sheet made of polycarbonate resin becomes difficult to remove from the mold. On the other hand, when the mold temperature is below 70°C, the resin solidifies too quickly in the mold during molding, making it difficult to control the shape of the molded sheet and making it difficult to fully transfer the shape given by the mold.

[0214] The optical lens disclosed herein can be appropriately used in the form of an aspherical lens as needed. An aspherical lens can achieve essentially zero spherical aberration using a single lens, thus eliminating the need for a combination of multiple spherical lenses to eliminate spherical aberration, enabling weight reduction and lower manufacturing costs. Therefore, aspherical lenses are particularly useful as camera lenses in optical applications.

[0215] Furthermore, the polycarbonate resin disclosed herein is particularly useful as a material for thin-walled, small, and complex-shaped optical lenses due to its high molding fluidity. Specifically, the thickness of the central portion is 0.05–3.0 mm, more preferably 0.05–2.0 mm, and even more preferably 0.1–2.0 mm. The diameter is 1.0 mm–20.0 mm, more preferably 1.0–10.0 mm, and even more preferably 3.0–10.0 mm. Furthermore, the shape is preferably a meniscus lens with one convex and one concave side.

[0216] Lenses made of the polycarbonate resin disclosed herein can be formed by any method, such as molding, cutting, grinding, laser processing, electrical discharge machining, or etching. Among these methods, molding is preferred from a manufacturing cost perspective.

[0217] [Example]

[0218] The following examples illustrate the polycarbonate resin of this disclosure in more detail. The materials, amounts, proportions, processing steps, etc., shown in the following examples can be appropriately modified without departing from the spirit of this disclosure. Therefore, the scope of the polycarbonate resin of this disclosure should not be limited by the specific examples shown below.

[0219] (Measurement methods, evaluation methods)

[0220] The measurement and evaluation methods applied to the examples and comparative examples are as follows.

[0221] <Copolymer ratio of polycarbonate resin>

[0222] The JEOL-manufactured JNM-ECZ400S was used for determination. 1 The copolymerization ratio of each polycarbonate resin can be calculated by H NMR.

[0223] <Weight-average molecular weight (Mw)>

[0224] The weight-average molecular weight (Mw) was determined using an EcoSEC HLC-8320 GPC prepared by TOSOH under the following conditions.

[0225] Detector: UV-8420; Solvent: Chloroform; Column: TOSOH TSKgel Supermultipore HZM-M ×3+ TSKgel guardcolumn (4.6×200nm); Measurement temperature: 40℃; Flow rate: 0.35ml / min; Injection volume: 5μl; Sample concentration: 1mg / 5ml; Standard sample: TSK polystyrene standard.

[0226] <Refractive Index>

[0227] After preparing 3mm thick test pieces of each polycarbonate resin and grinding them, the refractive index nd (587.56nm) was measured using a Shimadzu KALNEW precision refractometer KPR-2000.

[0228] <Abbe Numbers>

[0229] The Abbe number (νd) is calculated using the following formula based on the refractive index at wavelengths of 486.13 nm, 587.56 nm, and 656.27 nm at a temperature of 20 °C.

[0230] νd=(nd-1) / (nF-nC)

[0231] nd represents the refractive index at a wavelength of 587.56 nm.

[0232] nF represents the refractive index at a wavelength of 486.13 nm.

[0233] nC represents the refractive index at a wavelength of 656.27 nm.

[0234] <Absolute value of orientation birefringence (|Δn|)>

[0235] Polycarbonate resin was dissolved in dichloromethane and cast onto a glass petri dish, then thoroughly dried to produce a 100 μm thick cast film. A 70 mm long (45 mm between clamps) and 15 mm wide test piece was cut from this film and subjected to a 2x stretch at Tg+10℃. The phase difference (Re) at 589 nm was measured using a Nippon Spectroradiometer M-220, and the absolute value of the orientation birefringence (|Δn|) was calculated using the following formula.

[0236] |Δn|=|Re / d|

[0237] Δn: Orientation birefringence

[0238] Re: Phase difference (nm)

[0239] d: Thickness (nm)

[0240] <Photoelastic coefficient>

[0241] Polycarbonate resin was dissolved in dichloromethane and cast onto a glass petri dish, then thoroughly dried to produce a 100 μm thick cast film. Test pieces measuring 50 mm in length and 10 mm in width were cut from this film, and the photoelastic coefficient was determined using an M-220 ellipsometry manufactured by Nippon Spectroradiometer Co., Ltd.

[0242] <Glass transition temperature (Tg)>

[0243] The obtained polycarbonate resin was measured using a Discovery DSC25Auto differential scanning calorimeter manufactured by TA Instruments Japan Co., Ltd., at a heating rate of 20 °C / min. Samples were measured in doses of 5–10 mg.

[0244] <Thermal decomposition temperature (Td-5)>

[0245] The obtained polycarbonate resin was analyzed using a TA Instruments Japan SDT650 simultaneous thermal analyzer at a heating rate of 20°C / min. The temperature at which the weight decreased by 5% was determined based on the weight at 50°C. Samples were analyzed in doses of 3–4 mg.

[0246] <θgF>

[0247] The partial dispersion ratio (θgF) from the g line to the F line is calculated using the following formula based on the refractive index at wavelengths of 435.83 nm, 587.56 nm, and 656.27 nm at a temperature of 20 °C.

[0248] θgF=(ng-nF) / (nF-nC)

[0249] ng represents the refractive index at a wavelength of 435.83 nm.

[0250] nF represents the refractive index at a wavelength of 486.13 nm.

[0251] nC represents the refractive index at a wavelength of 656.27 nm.

[0252] <Ratio of terminal phenolic hydroxyl groups>

[0253] The ratio of terminal phenolic hydroxyl groups can be calculated as follows.

[0254] The ratio of terminal phenolic hydroxyl groups = (amount of terminal phenolic hydroxyl groups / total amount of terminal hydroxyl groups) × 100

[0255] Specifically, the ratio of terminal phenolic hydroxyl groups can be determined using the following method.

[0256] (1) Through polycarbonate resin 1 H NMR measurements were used to observe the terminal phenolic hydroxyl groups, and the integral of the corresponding peak was set to 1. At the same time, the integral intensity (A) of one proton of the fluorene structure was calculated based on the integral intensities of the peaks at positions 4 and 5 of the fluorene structure from the above formula (3). When no peak of the terminal phenolic hydroxyl group was observed, the ratio of terminal phenolic hydroxyl groups was 0.

[0257] (2) The average degree of polymerization of polycarbonate resin is determined based on the average molecular weight of polycarbonate resin obtained by GPC and the molecular weight and molar ratio of each repeating unit. Based on the mol% and integral intensity (A) of the above formula (3), the end-capacity is calculated by the following formula. 1 Integral intensity (B) in H NMR spectrum.

[0258] (B) = (A) × 100 × 2 / ([mol% of the above formula (3)] × average degree of polymerization)

[0259] (3) The ratio of terminal phenolic hydroxyl groups is calculated as 1 / (B)×100.

[0260] (The first type of polycarbonate resin)

[0261] <Example 1-1>

[0262] 3.51 g (0.01 mol) of 9,9-bis[4-(2-hydroxyethoxy)phenyl]fluorene (hereinafter sometimes referred to as BPEF), 97.61 g (0.37 mol) of pentacyclopentadecanedimethanol (hereinafter sometimes referred to as PCPDM), 6.2 g (0.02 mol) of 4,4'-(3,3,5-trimethylcyclohexylidene)bisphenol (hereinafter referred to as "BisTMC"), 89.12 g (0.42 mol) of diphenyl carbonate, and 17 μL (1 μmol) of a 60 mmol / L sodium bicarbonate aqueous solution and 22 μL (6 μmol) of a 274 mmol / L tetramethylammonium hydroxide aqueous solution as catalysts were heated to 180 °C under a nitrogen atmosphere to melt them. Then, the pressure inside the reactor was reduced to 20 kPa over 40 minutes, while the temperature was increased to 250 °C at a rate of 60 °C / hr. After 70% of the theoretical amount of phenol is distilled off, the pressure inside the reactor is brought down to below 133 Pa for 1 hour. Then, the reaction is stopped by stirring at 260°C for 40 minutes at a pressure below 133 Pa, and the resin is removed. 1 The copolymerization ratios of BPEF, PCPDM, and BisTMC in the obtained polycarbonate resin were determined by ¹H NMR. The weight-average molecular weight (Mw), refractive index, Abbe number, θgF, glass transition temperature, thermal decomposition temperature, absolute value of orientation birefringence, and photoelastic coefficient of the polycarbonate resin were evaluated. Furthermore, the proportion of terminal phenolic hydroxyl groups in this polycarbonate resin was 0%.

[0263] <Examples 1-2>

[0264] The amount of BPEF added was 22.80 g (0.5 mol), and the amount of PCPDM added was 86.06 g (0.33 mol). Otherwise, the polycarbonate resin was manufactured in the same manner as in Examples 1-1. 1 The copolymerization ratios of BPEF, PCPDM, and BisTMC in the obtained polycarbonate resin were determined by ¹H NMR. The weight-average molecular weight (Mw), refractive index, Abbe number, θgF, glass transition temperature, thermal decomposition temperature, absolute value of orientation birefringence, and photoelastic coefficient of the polycarbonate resin were evaluated. Furthermore, the proportion of terminal phenolic hydroxyl groups in this polycarbonate resin was 0%.

[0265] <Examples 1-3>

[0266] The amount of BPEF added was 31.57 g (0.07 mol), and the amount of PCPDM added was 80.82 g (0.31 mol). Otherwise, the polycarbonate resin was manufactured in the same manner as in Examples 1-1. 1The copolymerization ratios of BPEF, PCPDM, and BisTMC in the obtained polycarbonate resin were determined by ¹H NMR. The weight-average molecular weight (Mw), refractive index, Abbe number, θgF, glass transition temperature, thermal decomposition temperature, absolute value of orientation birefringence, and photoelastic coefficient of the polycarbonate resin were evaluated. Furthermore, the proportion of terminal phenolic hydroxyl groups in this polycarbonate resin was 0%.

[0267] <Examples 1-4>

[0268] The amount of BPEF added was 61.39 g (0.14 mol), and the amount of PCPDM added was 62.97 g (0.24 mol). Otherwise, the polycarbonate resin was manufactured in the same manner as in Examples 1-1. 1 The copolymerization ratios of BPEF, PCPDM, and BisTMC in the obtained polycarbonate resin were determined by ¹H NMR. The weight-average molecular weight (Mw), refractive index, Abbe number, θgF, glass transition temperature, thermal decomposition temperature, absolute value of orientation birefringence, and photoelastic coefficient of the polycarbonate resin were evaluated. Furthermore, the proportion of terminal phenolic hydroxyl groups in this polycarbonate resin was 0%.

[0269] <Examples 1-5>

[0270] The polycarbonate resin was prepared in the same manner as in Examples 1-1, with BPEF weighing 70.16 g (0.16 mol), PCPDM weighing 52.48 g (0.2 mol), and BisTMC weighing 12.40 g (0.04 mol). 1 The copolymerization ratios of BPEF, PCPDM, and BisTMC in the obtained polycarbonate resin were determined by ¹H NMR. The weight-average molecular weight (Mw), refractive index, Abbe number, θgF, glass transition temperature, thermal decomposition temperature, absolute value of orientation birefringence, and photoelastic coefficient of the polycarbonate resin were evaluated. Furthermore, the proportion of terminal phenolic hydroxyl groups in this polycarbonate resin was 0%.

[0271] <Examples 1-6>

[0272] The polycarbonate resin was prepared in the same manner as in Examples 1-1, with BPEF weighing 17.54 g (0.04 mol), PCPDM weighing 62.97 g (0.24 mol), and BisTMC weighing 37.2 g (0.12 mol). 1The copolymerization ratios of BPEF, PCPDM, and BisTMC in the obtained polycarbonate resin were determined by ¹H NMR. The weight-average molecular weight (Mw), refractive index, Abbe number, θgF, glass transition temperature, thermal decomposition temperature, absolute value of orientation birefringence, and photoelastic coefficient of the polycarbonate resin were evaluated. Furthermore, the proportion of terminal phenolic hydroxyl groups in this polycarbonate resin was 0%.

[0273] <Comparative Example 1-1>

[0274] 45.66 g (0.20 mol) of bisphenol A (hereinafter sometimes referred to as BPA), 52.48 g (0.20 mol) of PCPDM, 86.97 g (0.406 mol) of diphenyl carbonate, and 1.09 mg (12 μmol) of sodium bicarbonate as a catalyst were heated to 180 °C under a nitrogen atmosphere to melt them. Then, the reactor pressure was increased to 20 kPa (150 mmHg), and the temperature was raised to 200 °C at a rate of 60 °C / hr, and maintained at this temperature for 40 minutes. Next, the temperature was increased to 225 °C at a rate of 75 °C / hr, and after 40 minutes of heating, the reactor pressure was reduced to below 133 Pa (1 mmHg) for 1 hour while maintaining this temperature. Then, the temperature was increased to 235 °C at a rate of 105 °C / hr, and the reaction was carried out for a total of 6 hours with stirring. After the reaction was completed, nitrogen was purged into the reactor to restore atmospheric pressure, and the resulting resin was removed. 1 The copolymerization ratio of BPA and PCPDM in the obtained polycarbonate resin was determined by ¹H NMR. The weight-average molecular weight (Mw), refractive index, Abbe number, θgF, glass transition temperature, thermal decomposition temperature, absolute value of orientation birefringence, and photoelastic coefficient of the polycarbonate resin were evaluated.

[0275] <Comparative Examples 1-2>

[0276] The amount of BPA added was 63.92 g (0.28 mol), and the amount of PCPDM added was 31.49 g (0.12 mol). Otherwise, the polycarbonate resin was manufactured in the same manner as in Comparative Example 1-1. 1 The copolymerization ratio of BPA and PCPDM in the obtained polycarbonate resin was determined by ¹H NMR. The weight-average molecular weight (Mw), refractive index, Abbe number, θgF, glass transition temperature, thermal decomposition temperature, absolute value of orientation birefringence, and photoelastic coefficient of the polycarbonate resin were evaluated.

[0277] <Comparative Examples 1-3>

[0278] The polycarbonate resin was manufactured in the same manner as in Comparative Example 1-1, with BPA added at a rate of 27.40 g (0.12 mol) and PCPDM added at a rate of 73.47 g (0.28 mol).1 The copolymerization ratio of BPA and PCPDM in the obtained polycarbonate resin was determined by ¹H NMR. The weight-average molecular weight (Mw), refractive index, Abbe number, θgF, glass transition temperature, thermal decomposition temperature, absolute value of orientation birefringence, and photoelastic coefficient of the polycarbonate resin were evaluated.

[0279] <Comparative Examples 1-4>

[0280] 103.49 g (0.24 mol) of BPEF, 37.80 g (0.12 mol) of 3,9-bis(2-hydroxy-1,1-dimethylethyl)-2,4,8,10-tetraoxaziro(5.5)undecane (hereinafter referred to as "SPG"), 12.42 g (0.04 mol) of BisTMC, 89.11 g (0.42 mol) of diphenyl carbonate, and 0.033 mL (2.0 μmol) of a 60 mmol / L sodium bicarbonate aqueous solution as a catalyst were heated to 180 °C under a nitrogen atmosphere to melt them. Then, the pressure was adjusted to 20 kPa over 10 minutes. The temperature was increased to 250 °C at a rate of 60 °C / hr. After the phenol outflow reached 70%, the pressure inside the reactor was reduced to below 133 Pa over 1 hour. The reaction was carried out with stirring for a total of 3.5 hours. After the reaction was completed, the resin was removed from the flask. 1 The copolymerization ratios of the obtained polycarbonate resin derived from BPEF, SPG, and BisTMC were determined by ¹H NMR. The weight-average molecular weight (Mw), refractive index, Abbe number, θgF, glass transition temperature, thermal decomposition temperature, absolute value of orientation birefringence, and photoelastic coefficient of the polycarbonate resin were evaluated.

[0281] <Comparative Examples 1-5>

[0282] The polycarbonate resin was prepared in the same manner as in Comparative Examples 1-4, with BPEF added at a rate of 96.47 g (0.22 mol), SPG at a rate of 38.96 g (0.13 mol), and BisTMC at a rate of 16.12 g (0.05 mol). 1 The copolymerization ratios of the obtained polycarbonate resin derived from BPEF, SPG, and BisTMC were determined by ¹H NMR. The weight-average molecular weight (Mw), refractive index, Abbe number, θgF, glass transition temperature, thermal decomposition temperature, absolute value of orientation birefringence, and photoelastic coefficient of the polycarbonate resin were evaluated.

[0283] <Comparative Examples 1-6>

[0284] The polycarbonate resin was manufactured in the same manner as in Comparative Examples 1-4, with BPEF added at a rate of 21.05 g (0.05 mol), SPG at a rate of 69.40 g (0.23 mol), and BisTMC at a rate of 38.44 g (0.12 mol). 1 The copolymerization ratios of the obtained polycarbonate resin derived from BPEF, SPG, and BisTMC were determined by ¹H NMR. The weight-average molecular weight (Mw), refractive index, Abbe number, θgF, glass transition temperature, thermal decomposition temperature, absolute value of orientation birefringence, and photoelastic coefficient of the polycarbonate resin were evaluated.

[0285]

[0286] The polycarbonate resins in Examples 1-1 to 1-6 of the first aspect of this disclosure exhibit characteristics of maintaining a high balance between refractive index (nd) and Abbe number (νd) while having low oriented birefringence (|Δn|) and photoelastic coefficient.

[0287] Compared with Comparative Examples 1-1 and 1-2, which correspond to embodiments of Patent Document 1, the embodiments 1-1 to 1-6 of the first aspect of this disclosure exhibit superior orientational birefringence. Therefore, when optical components are obtained by injection molding or the like, birefringence due to molecular orientation is less likely to occur. Furthermore, due to the low photoelasticity coefficient, birefringence due to stress is less likely to occur when optical components are obtained by injection molding or the like. Therefore, the birefringence of the optical component is reduced, which is preferable.

[0288] Compared with Comparative Examples 1-3, the first embodiments of this disclosure 1-2 have higher glass transition temperatures and better heat resistance, and are therefore preferred.

[0289] The embodiments 1-1 to 1-3 and 1-6 of the first aspect of this disclosure have the same or higher Abbe number as the comparative examples 1-6 of the embodiment corresponding to Patent Document 4, and at the same time have a higher refractive index, which enables the optical lens to be thinner.

[0290] The embodiments 1-4 of the first aspect of this disclosure have the same refractive index as the comparative examples 1-5 of the embodiments corresponding to Patent Document 3, while having a higher Abbe number, which expands the range of optical designs.

[0291] The embodiments 1-5 of the first aspect of this disclosure have the same refractive index as comparative examples 1-4 and 1-5, which are equivalent to the embodiments of Patent Document 3, but have a higher Abbe number, thus expanding the range of optical designs.

[0292] like Figure 1As shown, when plotting the refractive index and Abbe number, the comparative example has an Abbe number of 27.6 at a high refractive index. In contrast, the polycarbonate resin of the first embodiment of this disclosure has an Abbe number of 31.0 with the same refractive index, which is higher than the range of the prior art. Therefore, chromatic aberration of optical components can be reduced.

[0293] (The second type of polycarbonate resin)

[0294] <Example 2-1>

[0295] 83.32 g (0.19 mol) of 9,9-bis[4-(2-hydroxyethoxy)phenyl]fluorene (hereinafter sometimes referred to as BPEF), 49.85 g (0.19 mol) of pentacyclopentadecanedimethanol (hereinafter sometimes referred to as PCPDM), 6.20 g (0.02 mol) of 4,4'-(3,3,5-trimethylcyclohexylidene)bisphenol (hereinafter referred to as BisTMC), 89.12 g (0.42 mol) of diphenyl carbonate, and 17 μL (1 μmol) of a 60 mmol / L sodium bicarbonate aqueous solution and 22 μL (6 μmol) of a 274 mmol / L tetramethylammonium hydroxide aqueous solution as catalysts were heated to 180 °C under a nitrogen atmosphere to melt them. Then, the pressure inside the reactor was reduced to 20 kPa over 40 minutes, while the temperature was increased to 250 °C at a rate of 60 °C / hr. After distilling off 70% of the theoretical amount of phenol, the reactor pressure is lowered to below 133 Pa for 1 hour. Then, the reaction is stopped by stirring at 260°C for 40 minutes at a pressure below 133 Pa, and the resin is removed. 1 The copolymerization ratios of BPEF, PCPDM, and BisTMC in the obtained polycarbonate resin were determined by ¹H NMR. The weight-average molecular weight (Mw), refractive index, Abbe number, θgF, glass transition temperature, thermal decomposition temperature, absolute value of orientation birefringence, and photoelastic coefficient of the polycarbonate resin were evaluated. Furthermore, the proportion of terminal phenolic hydroxyl groups in this polycarbonate resin was 0%.

[0296] <Example 2-2>

[0297] The amount of BPEF added was 135.06 g (0.31 mol), and the amount of PCPDM added was 18.89 g (0.07 mol). Otherwise, the polycarbonate resin was manufactured in the same manner as in Example 2-1. 1The copolymerization ratios of BPEF, PCPDM, and BisTMC in the obtained polycarbonate resin were determined by ¹H NMR. The weight-average molecular weight (Mw), refractive index, Abbe number, θgF, glass transition temperature, thermal decomposition temperature, absolute value of orientation birefringence, and photoelastic coefficient of the polycarbonate resin were evaluated. Furthermore, the proportion of terminal phenolic hydroxyl groups in this polycarbonate resin was 0%.

[0298] <Example 2-3>

[0299] The amount of BPEF added was 163.13 g (0.37 mol), and the amount of PCPDM added was 2.10 g (0.01 mol). Otherwise, the polycarbonate resin was manufactured in the same manner as in Example 2-1. 1 The copolymerization ratios of BPEF, PCPDM, and BisTMC in the obtained polycarbonate resin were determined by ¹H NMR. The weight-average molecular weight (Mw), refractive index, Abbe number, θgF, glass transition temperature, thermal decomposition temperature, absolute value of orientation birefringence, and photoelastic coefficient of the polycarbonate resin were evaluated. Furthermore, the proportion of terminal phenolic hydroxyl groups in this polycarbonate resin was 0%.

[0300] <Example 2-4>

[0301] The polycarbonate resin was prepared in the same manner as in Example 2-1, with BPEF weighing 70.16 g (0.16 mol), PCPDM weighing 47.23 g (0.18 mol), and BisTMC weighing 18.60 g (0.06 mol). 1 The copolymerization ratios of BPEF, PCPDM, and BisTMC in the obtained polycarbonate resin were determined by ¹H NMR. The weight-average molecular weight (Mw), refractive index, Abbe number, θgF, glass transition temperature, thermal decomposition temperature, absolute value of orientation birefringence, and photoelastic coefficient of the polycarbonate resin were evaluated. Furthermore, the proportion of terminal phenolic hydroxyl groups in this polycarbonate resin was 0%.

[0302] <Examples 2-5>

[0303] The polycarbonate resin was prepared in the same manner as in Example 2-1, with BPEF weighing 26.31 g (0.06 mol), PCPDM weighing 47.23 g (0.18 mol), and BisTMC weighing 49.60 g (0.16 mol). 1The copolymerization ratios of BPEF, PCPDM, and BisTMC in the obtained polycarbonate resin were determined by ¹H NMR. The weight-average molecular weight (Mw), refractive index, Abbe number, θgF, glass transition temperature, thermal decomposition temperature, absolute value of orientation birefringence, and photoelastic coefficient of the polycarbonate resin were evaluated. Furthermore, the proportion of terminal phenolic hydroxyl groups in this polycarbonate resin was 0%.

[0304] <Example 2-6>

[0305] The polycarbonate resin was prepared in the same manner as in Example 2-1, with BPEF weighing 87.70 g (0.20 mol), PCPDM weighing 26.24 g (0.10 mol), and BisTMC weighing 31.00 g (0.10 mol). 1 The copolymerization ratios of BPEF, PCPDM, and BisTMC in the obtained polycarbonate resin were determined by ¹H NMR. The weight-average molecular weight (Mw), refractive index, Abbe number, θgF, glass transition temperature, thermal decomposition temperature, absolute value of orientation birefringence, and photoelastic coefficient of the polycarbonate resin were evaluated. Furthermore, the proportion of terminal phenolic hydroxyl groups in this polycarbonate resin was 0%.

[0306] <Comparative Example 2-1>

[0307] 45.66 g (0.20 mol) of bisphenol A (hereinafter sometimes referred to as BPA), 52.48 g (0.20 mol) of PCPDM, 86.97 g (0.406 mol) of diphenyl carbonate, and 1.09 mg (12 μmol) of sodium bicarbonate as a catalyst were heated to 180 °C under a nitrogen atmosphere to melt them. Then, the reactor pressure was increased to 20 kPa (150 mmHg), and the temperature was raised to 200 °C at a rate of 60 °C / hr, and maintained at this temperature for 40 minutes. Next, the temperature was increased to 225 °C at a rate of 75 °C / hr, and after 40 minutes of heating, the reactor pressure was reduced to below 133 Pa (1 mmHg) for 1 hour while maintaining this temperature. Then, the temperature was increased to 235 °C at a rate of 105 °C / hr, and the reaction was carried out for a total of 6 hours with stirring. After the reaction was completed, nitrogen was purged into the reactor to restore atmospheric pressure, and the resulting resin was removed. 1 The copolymerization ratio of BPA and PCPDM in the obtained polycarbonate resin was determined by ¹H NMR. The weight-average molecular weight (Mw), refractive index, Abbe number, glass transition temperature, thermal decomposition temperature, absolute value of orientation birefringence, and photoelastic coefficient of the polycarbonate resin were evaluated.

[0308] <Comparative Example 2-2>

[0309] The amount of BPA added was 63.92 g (0.28 mol), and the amount of PCPDM added was 31.49 g (0.12 mol). Otherwise, the polycarbonate resin was manufactured in the same manner as in Comparative Example 2-1. 1 The copolymerization ratio of BPA and PCPDM in the obtained polycarbonate resin was determined by ¹H NMR. The weight-average molecular weight (Mw), refractive index, Abbe number, θgF, glass transition temperature, thermal decomposition temperature, absolute value of orientation birefringence, and photoelastic coefficient of the polycarbonate resin were evaluated.

[0310] <Comparative Examples 2-3>

[0311] 42.10 g (0.10 mol) of BPEF, 57.22 g (0.19 mol) of SPG, 35.96 g (0.12 mol) of BisTMC, 89.12 g (0.42 mol) of diphenyl carbonate, and 33 μL (2 μmol) of a 60 mmol / L sodium bicarbonate aqueous solution as a catalyst were heated to 180 °C under a nitrogen atmosphere to melt them. The pressure was then adjusted to 20 kPa over 10 minutes. The temperature was increased to 250 °C at a rate of 60 °C / hr. After the phenol outflow reached 70%, the pressure inside the reactor was brought down to below 133 Pa over 1 hour. The reaction was carried out with stirring for a total of 3.5 hours. After the reaction was complete, the resin was removed from the flask. 1 The copolymerization ratios of the obtained polycarbonate resin derived from BPEF, SPG, and BisTMC were determined by ¹H NMR. The weight-average molecular weight (Mw), refractive index, Abbe number, θgF, glass transition temperature, thermal decomposition temperature, absolute value of orientation birefringence, and photoelastic coefficient of the polycarbonate resin were evaluated.

[0312] <Comparative Examples 2-4>

[0313] The polycarbonate resin was prepared in the same manner as in Comparative Examples 2-3, with BPEF of 103.49 g (0.24 mol), SPG of 37.74 g (0.12 mol), and BisTMC of 12.40 g (0.04 mol). 1 The copolymerization ratios of the obtained polycarbonate resin derived from BPEF, SPG, and BisTMC were determined by ¹H NMR. The weight-average molecular weight (Mw), refractive index, Abbe number, θgF, glass transition temperature, thermal decomposition temperature, absolute value of orientation birefringence, and photoelastic coefficient of the polycarbonate resin were evaluated.

[0314] <Comparative Examples 2-5>

[0315] The polycarbonate resin was prepared in the same manner as in Comparative Examples 2-3, with BPEF of 26.31 g (0.06 mol), SPG of 54.79 g (0.18 mol), and BisTMC of 49.60 g (0.16 mol). 1 The copolymerization ratios of the obtained polycarbonate resin derived from BPEF, SPG, and BisTMC were determined by ¹H NMR. The weight-average molecular weight (Mw), refractive index, Abbe number, θgF, glass transition temperature, thermal decomposition temperature, absolute value of orientation birefringence, and photoelastic coefficient of the polycarbonate resin were evaluated.

[0316] <Comparative Examples 2-6>

[0317] The polycarbonate resin was prepared in the same manner as in Comparative Examples 2-3, with BPEF of 87.70 g (0.20 mol), SPG of 30.44 g (0.10 mol), and BisTMC of 31.00 g (0.10 mol). 1 The copolymerization ratios of the obtained polycarbonate resin derived from BPEF, SPG, and BisTMC were determined by ¹H NMR. The weight-average molecular weight (Mw), refractive index, Abbe number, θgF, glass transition temperature, thermal decomposition temperature, absolute value of orientation birefringence, and photoelastic coefficient of the polycarbonate resin were evaluated.

[0318]

[0319] The polycarbonate resins in Examples 2-1 to 2-6 of the second aspect of this disclosure exhibit characteristics of low oriented birefringence (|Δn|) and high refractive index (nd) and glass transition temperature (Tg).

[0320] Compared with Comparative Examples 2-1 and 2-2, which correspond to the embodiments of Patent Document 1, the second embodiments 2-1 to 2-6 of this disclosure have excellent orientational birefringence and photoelastic coefficient. Therefore, when optical components are obtained by injection molding or the like, birefringence is less likely to occur due to molecular orientation or stress. In addition, due to their high refractive index and glass transition temperature, they are preferred as optical components.

[0321] Embodiments 2-2 and 2-3 of the second aspect of this disclosure are preferred over comparative examples 2-3 to 2-6, which correspond to embodiments of Patent Documents 3 and 4, due to their superior orientation birefringence. Furthermore, they are preferred due to their high glass transition temperature and excellent heat resistance.

[0322] The embodiments 2-4 of the second aspect of this disclosure have the same refractive index as comparative examples 2-4 corresponding to the embodiments of Patent Document 4, while having a higher Abbe number, which expands the range of optical designs. Furthermore, they are preferred due to their high glass transition temperature and excellent heat resistance.

[0323] Embodiments 2-5 and 2-6 of the second aspect of this disclosure, compared with comparative examples 2-5 and 2-6 corresponding to embodiments of Patent Documents 3 and 4, have the same copolymer ratio and, by replacing SPG with PCPDM, achieve a higher refractive index at the same Abbe number, enabling thinner optical lenses. Furthermore, they are preferred due to their high glass transition temperature and excellent heat resistance.

[0324] like Figure 2 As shown, when plotting the refractive index and Abbe number, the comparative example has an Abbe number of 27.6 at a high refractive index, while the polycarbonate resin of the second embodiment of this disclosure has an Abbe number of 30.6 at the same refractive index. The Abbe number relative to the refractive index is higher than that of the prior art. Therefore, chromatic aberration of the optical components can be reduced.

[0325] Industrial availability

[0326] The polycarbonate resin disclosed herein can be used in optical materials and can be used in optical components such as lenses, prisms, optical discs, transparent conductive substrates, optical cards, sheets, thin films, optical fibers, optical films, filters, and hard coating films, and is especially useful for camera lenses.

[0327] The disclosure of Japanese Patent Application No. 2024-013876, filed on February 1, 2024, is incorporated herein by reference in its entirety. The disclosure of Japanese Patent Application No. 2024-013878, filed on February 1, 2024, is incorporated herein by reference in its entirety.

[0328] All documents, patent applications and technical standards described in this specification are incorporated herein by reference to the same extent that each document, patent application and technical standard is incorporated herein by reference in its entirety and as specifically and separately described therein.

Claims

1. A polycarbonate resin comprising repeating units represented by formula (1) and / or formula (2), repeating units represented by formula (3), and repeating units represented by formula (4), wherein the total number of repeating units represented by formula (1) and / or formula (2) in all repeating units of the resin is 50 mol% or more, and the polycarbonate resin has a weight-average molecular weight Mw of 10,000 or more. In the formula, R 1 ~R 4 Each can independently represent a hydrogen atom or a hydrocarbon group with 1 to 10 carbon atoms. In equation (4), n is in the range of 0 to 8, and R independently represents alkyl groups with 1 to 3 carbon atoms.

2. A polycarbonate resin comprising repeating units represented by formula (1) and / or formula (2), repeating units represented by formula (3), and repeating units represented by formula (4), wherein the total of repeating units represented by formula (1) and / or formula (2) in all repeating units of the resin exceeds 0 mol% and is less than 50 mol%, and the weight-average molecular weight Mw of the polycarbonate resin is 10000 or more. In the formula, R 1 ~R 4 Each can independently represent a hydrogen atom or a hydrocarbon group with 1 to 10 carbon atoms. In equation (4), n is in the range of 0 to 8, and R independently represents alkyl groups with 1 to 3 carbon atoms.

3. The polycarbonate resin according to claim 1 or 2, wherein, The weight-average molecular weight (Mw) is 10,000 to 60,000.

4. The polycarbonate resin according to claim 1, wherein, The repeating units represented by the formula (3) in all repeating units of the resin exceed 0 mol% and are less than 50 mol%.

5. The polycarbonate resin according to claim 2, wherein, The repeating units represented by the formula (3) in all repeating units of the resin are 10 mol% to 95 mol.

6. The polycarbonate resin according to claim 1, wherein, The repeating units represented by the formula (4) in all repeating units of the resin exceed 0 mol% and are less than 40 mol%.

7. The polycarbonate resin according to claim 2, wherein, The repeating units represented by the formula (4) in all repeating units of the resin exceed 0 mol% and are less than 45 mol%.

8. The polycarbonate resin according to claim 1 or 2, wherein, R in equation (3) 1 ~R 4 It is a hydrogen atom.

9. The polycarbonate resin according to claim 1 or 2, wherein, The repeating unit in formula (4) is a repeating unit derived from bisphenol TMC.

10. The polycarbonate resin according to claim 1 or 2, wherein, The absolute value of oriented birefringence is 10.0 × 10⁻⁶. -3 the following.

11. The polycarbonate resin according to claim 1, wherein, The photoelastic modulus is less than 25 × 10 -12 Pa.

12. The polycarbonate resin according to claim 2, wherein, The photoelastic modulus is 40×10 -12 Below Pa.

13. The polycarbonate resin according to claim 1, wherein, An Abbe number of 25.0 or higher.

14. The polycarbonate resin according to claim 2, wherein, The refractive index nd is above 1.

550.

15. The polycarbonate resin according to claim 2, wherein, The glass transition temperature is above 140℃.

16. An optical component comprising the polycarbonate resin of claim 1 or 2.

17. The optical component according to claim 16, wherein, The optical component is a camera lens.

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