Resin composition, pellets, and molded article

Abstract

The present invention provides a resin composition comprising a first polycarbonate resin, a second polycarbonate resin, and a styrene-based resin, in which the refractive index of the first polycarbonate resin, the refractive index of the second polycarbonate resin, and the refractive index of the styrene-based resin satisfy: the refractive index of the first polycarbonate resin [lt]; the refractive index of the styrene-based resin is 1t; the refractive index of the second polycarbonate resin and the haze when the resin composition is molded to a thickness of 3 mm are less than 20%. Also provided are pellets and molded articles using the resin composition.

Description

Technical Field

[0001] This invention relates to resin compositions, granules, and molded articles. In particular, it relates to resin compositions primarily composed of polycarbonate resins and styrene-based resins. Background Technology

[0002] Polycarbonate resin is widely used in various fields due to its excellent impact resistance, heat resistance, electrical insulation, and dimensional stability, as well as the good balance of these properties. In particular, polycarbonate resins made from bisphenol compounds exhibit excellent transparency, impact resistance, and heat resistance, and are lightweight and shatter-resistant, making them a viable alternative to glass in automotive components, building materials, and optical components such as lenses. Furthermore, in recent years, it has been widely used as a front panel component, especially for touch panels, in display devices such as smartphones, tablets, car navigation systems, car audio systems, portable game consoles, and digital cameras.

[0003] Besides transparency, birefringence is another important optical property to consider when manufacturing optical components from resin. Even with excellent transparency, high birefringence is undesirable. In particular, for various display devices such as cameras and LCD panels, as well as projectors, the presence of optical components with high birefringence in the optical path can adversely affect image quality and signal reading performance. Therefore, it is strongly recommended to use transparent resins with birefringence as low as possible.

[0004] Typical polycarbonate resins have a high birefringence. For example, in the front components of display devices, a high birefringence can lead to the following problems: phase difference, resulting in rainbow patterns; when viewing the image with polarized sunglasses, the rainbow patterns become more pronounced and indistinguishable, resulting in decreased visibility; and a significant reduction in design (aesthetics). Polycarbonate resins made from common bisphenol A tend to have a high birefringence.

[0005] In the past, various methods have been studied to reduce the birefringence of polycarbonate resins. It is known to use polycarbonate resins in which the resin itself is made of bisphenol with a specific structure. For example, Patent Document 1 discloses a special polycarbonate copolymer with low birefringence, which is made by copolymerizing spirobiindane bisphenol with bisphenol A.

[0006] Patent document 2 proposes that a resin composition made by combining styrene-maleic anhydride-N-phenylmaleimide copolymer resin (A) and acrylonitrile-styrene copolymer resin (B) in a ratio of 37-47% resin (A), 13-23% resin (B), and 35-45% polycarbonate resin can provide a resin composition with high heat resistance, high transparency, and low birefringence.

[0007] Existing technical documents

[0008] Patent documents

[0009] Patent Document 1: Japanese Patent Application Publication No. 06-313035

[0010] Patent Document 2: Japanese Patent Application Publication No. 2013-107933 Summary of the Invention

[0011] The problem that the invention aims to solve

[0012] However, the use of the special resin described in Patent Document 1 is limited by its price. On the other hand, although the resin composition described in Patent Document 2 is a resin composition with low birefringence, it has insufficient transparency and a high haze value.

[0013] To address this problem, the present invention aims to provide resin compositions, granules, and molded articles with low retardation and excellent transparency.

[0014] Problem Solving Methods

[0015] Based on the above-mentioned problems, the inventors conducted research and found that the above problems can be solved by mixing two or more polycarbonate resins and styrene resins with specific relationships to reduce the difference in refractive index between polycarbonate resins and styrene resins.

[0016] Specifically, the above problems were solved in the following way.

[0017] <1> A resin composition comprising a first polycarbonate resin, a second polycarbonate resin, and a styrene-based resin, wherein...

[0018] The refractive indices of the first polycarbonate resin, the second polycarbonate resin, and the styrene resin satisfy the following condition: refractive index of the first polycarbonate resin < refractive index of the styrene resin < refractive index of the second polycarbonate resin.

[0019] The haze of the resin composition when molded to a thickness of 3 mm is less than 20%.

[0020] <2> according to <1> The resin composition comprises 5 to 100 parts by weight of styrene resin relative to a total of 100 parts by weight of the first polycarbonate resin and the second polycarbonate resin.

[0021] <3> according to <1> or <2> The resin composition, wherein,

[0022] The refractive index of the first polycarbonate resin is greater than 1.570 and less than 1.590.

[0023] <4> according to <1> ~ <3> The resin composition described in any one of the following statements, wherein,

[0024] The first polycarbonate resin comprises a bisphenol A type aromatic polycarbonate resin.

[0025] <5> according to <1> ~ <4> The resin composition described in any one of the following statements, wherein,

[0026] The refractive index of the second polycarbonate resin is 1.590~1.700.

[0027] <6> according to <1> ~ <5> The resin composition described in any one of the following statements, wherein,

[0028] The second polycarbonate resin comprises bisphenol AP type aromatic polycarbonate resin.

[0029] <7> according to <1> ~ <6> The resin composition described in any one of the following statements, wherein,

[0030] The second polycarbonate resin comprises fluorene polycarbonate resin.

[0031] <8> according to <1> ~ <7> The resin composition described in any one of the following statements, wherein,

[0032] The refractive index of the styrene-based resin is 1.571~1.699.

[0033] <9> according to <1> ~ <8> The resin composition according to any one of the following is a styrene resin comprising more than 90% by mass of styrene monomer units, and at least one of the following: styrene resin comprising 20-90% by mass of styrene monomer units, 1-30% by mass of maleic anhydride monomer units, and 0-60% by mass of N-phenylmaleimide monomer units.

[0034] <10> according to <1> ~ <9> The resin composition described in any one of the following statements, wherein,

[0035] The styrene resin is a styrene resin in which more than 90% by mass of all monomer units are styrene monomer units.

[0036] <11> according to <1> ~ <10> The resin composition according to any one of the following methods comprises, relative to a total of 100 parts by weight of the first polycarbonate resin and the second polycarbonate resin, 50 to 97 parts by weight of the first polycarbonate resin and 3 to 50 parts by weight of the second polycarbonate resin.

[0037] <12> according to <1> ~ <11> The resin composition described in any one of the following statements, wherein,

[0038] The content of the styrene resin is less than 90 parts by mass relative to the total of 100 parts by mass of the first polycarbonate resin and the second polycarbonate resin, and the refractive index of the second polycarbonate resin is 1.590~1.700.

[0039] <13> according to <1> ~ <12> The resin composition described in any one of the following statements, wherein,

[0040] The content of the styrene resin is less than 90 parts by mass relative to the total of 100 parts by mass of the first polycarbonate resin and the second polycarbonate resin. The styrene resin is a styrene resin in which more than 90% by mass of all monomer units are styrene monomers.

[0041] <14> according to <1> ~ <13> The resin composition described in any one of the above statements comprises 5 to 100 parts by weight of a styrene resin relative to a total of 100 parts by weight of the first polycarbonate resin and the second polycarbonate resin.

[0042] The refractive index of the first polycarbonate resin is greater than 1.570 and less than 1.590.

[0043] The first polycarbonate resin comprises a bisphenol A type aromatic polycarbonate resin.

[0044] The refractive index of the second polycarbonate resin is 1.590~1.700.

[0045] The second polycarbonate resin comprises bisphenol AP type aromatic polycarbonate resin and / or fluorene polycarbonate resin.

[0046] The refractive index of the styrene-based resin is 1.571~1.699.

[0047] The styrene resin is a styrene resin in which more than 90% by mass of all monomer units are styrene monomer units.

[0048] <15> A resin composition comprising 5-100 parts by weight of a styrene resin in a total of 100 parts by weight relative to 50-97 parts by weight of a first polycarbonate resin and 3-50 parts by weight of a second polycarbonate resin.

[0049] The first polycarbonate resin comprises a bisphenol A type aromatic polycarbonate resin.

[0050] The second polycarbonate resin comprises bisphenol AP type aromatic polycarbonate resin and / or fluorene polycarbonate resin, the styrene resin comprises styrene resin in which more than 90% by mass of all monomer units are styrene monomers, and at least one of styrene resins containing 20-90% by mass of styrene monomer units, 1-30% by mass of maleic anhydride monomer units and 0-60% by mass of N-phenylmaleimide monomer units, and the haze of the resin composition when molded to a thickness of 3 mm is less than 20%.

[0051] <16> A type of particle, which is <1> ~ <15> The resin composition particles described in any one of the above statements.

[0052] <17> A molded product, which is made of <1> ~ <15> The resin composition described in any one of the above statements is formed.

[0053] <18> A molded product, which is made of <16> The aforementioned particle formation.

[0054] <19> A lens, which is made of <1> ~ <15> The resin composition is formed.

[0055] <20> A lens, which is made of <16> The particles are formed by molding.

[0056] The effects of the invention

[0057] According to the present invention, resin compositions, granules and molded articles with low delay and excellent transparency can be provided. Detailed Implementation

[0058] The following describes in detail the method for implementing the present invention (hereinafter referred to as "this embodiment"). It should be noted that the following embodiment is an example for illustrating the present invention, and the present invention is not limited to this embodiment.

[0059] It should be noted that in this specification, "~" is used to indicate the lower and upper limits of the values ​​contained before and after it.

[0060] Unless otherwise specified, all physical property values ​​and characteristic values ​​in this specification are values ​​at 23°C.

[0061] Unless otherwise specified, the measurement methods described in this specification are based on the time point of January 1, 2023, and may vary from year to year.

[0062] The resin composition of this embodiment is a resin composition comprising a first polycarbonate resin, a second polycarbonate resin, and a styrene-based resin, wherein the refractive index of the first polycarbonate resin, the refractive index of the second polycarbonate resin, and the refractive index of the styrene-based resin satisfy the condition that the refractive index of the first polycarbonate resin < the refractive index of the styrene-based resin < the refractive index of the second polycarbonate resin, and the haze when the above resin composition is molded to a thickness of 3 mm is less than 20%.

[0063] By configuring it in this way, a resin composition that can provide molded articles with low delay and excellent transparency can be obtained.

[0064] The retardation is caused by the difference in refractive index between the two intrinsically polarized rays. Since polycarbonate resin has positive birefringence, the retardation can be reduced by incorporating a material with negative birefringence, which is opposite to that of polycarbonate resin. In this embodiment, the styrene resin is incorporated into the polycarbonate resin in such a manner that the refractive index of the first polycarbonate resin, the refractive index of the second polycarbonate resin, and the refractive index of the styrene resin are in the order that the refractive index of the first polycarbonate resin < the refractive index of the styrene resin < the refractive index of the second polycarbonate resin. As a result, the first and second polycarbonate resins are compatible to form a sea-like structure, the styrene resin forms an island-like structure, and the refractive index difference between the polycarbonate resin region (sea) and the styrene resin (island) is reduced, which presumably provides a material with low retardation and high transparency.

[0065] <Polycarbonate resin>

[0066] The resin composition of this embodiment comprises a first polycarbonate resin and a second polycarbonate resin. The refractive index of the first polycarbonate resin is lower than that of the styrene-based resin, and the refractive index of the second polycarbonate resin is higher than that of the styrene-based resin. By including polycarbonate resins with different refractive indices in this way, the refractive index difference with the styrene-based resin can be reduced.

[0067] The polycarbonate resin is not particularly limited as long as it contains -[OR-OC(=O)]- units with carbonate bonds in the main molecular chain (R is an organic group, preferably a hydrocarbon group, more preferably an aliphatic group, an aromatic group, or a group containing both aliphatic and aromatic groups, and further having a straight-chain structure or a branched structure). In this embodiment, the first polycarbonate resin and the second polycarbonate resin are each preferably aromatic polycarbonate resins, more preferably bisphenol-type aromatic polycarbonate resins.

[0068] In this embodiment, bisphenol-type aromatic polycarbonate resin refers to a resin in which 90 mol% or more of all structural units are structural units with a bisphenol backbone (also called monomer units), preferably 95 mol% or more of all structural units are structural units with a bisphenol backbone. The same can be considered for bisphenol A-type aromatic polycarbonate resin, bisphenol AP-type aromatic polycarbonate resin, etc., as described below.

[0069] As other structural units, reference can be made to the structural unit represented by formula (1) described in paragraph 0008 of International Publication No. 2017 / 099226, the descriptions in paragraphs 0043 to 0052 of International Publication No. 2017 / 099226, and the descriptions in Japanese Patent Application Publication No. 2011-046769, which are incorporated herein by reference.

[0070] The refractive index of the first polycarbonate resin is preferably 1.570 or higher, more preferably 1.575 or higher, even more preferably 1.580 or higher, and preferably less than 1.590, more preferably 1.588 or lower, and even more preferably 1.585 or lower. By setting it to the lower limit or higher and the upper limit or lower, the types of polystyrene resins that can be applied increase, and there is a tendency to easily impart the desired properties to the obtained resin composition or molded article.

[0071] When the resin composition of this embodiment contains two or more first polycarbonate resins, the sum of the values ​​obtained by multiplying the refractive index of each first polycarbonate resin by the mass fraction of each first polycarbonate in the first polycarbonate is used as the refractive index of the first polycarbonate resin. The same applies to the second polycarbonate resin and styrene-based resins.

[0072] The difference in refractive index between the first polycarbonate resin and the styrene resin is greater than 0. Furthermore, it is preferably 0.100 or less, more preferably 0.080 or less, even more preferably 0.040 or less, even more preferably 0.030 or less, even more preferably 0.020 or less, and even more preferably 0.010 or less.

[0073] The viscosity-average molecular weight (Mv) of the first polycarbonate resin is preferably 9,000 or more, more preferably 10,000 or more, and even more preferably 15,000 or more. Furthermore, the upper limit of Mv is preferably 100,000 or less, more preferably 80,000 or less, even more preferably 50,000 or less, and even more preferably 30,000 or less. By setting it to the lower limit or below the above-mentioned values, there is a tendency to further reduce the delay of the obtained molded article.

[0074] The viscosity-average molecular weight (Mv) of polycarbonate resin is calculated using dichloromethane as a solvent, the limiting viscosity (η) at 20°C (unit: dL / g) determined by an Ubbelohde viscometer, and the viscosity formula of Schnell as follows.

[0075] η = 1.23 × 10 -4 Mv 0.83

[0076] In the case where the resin composition of this embodiment contains two or more first polycarbonate resins, the value is defined as the sum of the values ​​obtained by multiplying the viscosity-average molecular weight of each polycarbonate resin by its mass fraction.

[0077] The preferred MVR of the first polycarbonate resin, measured at 300°C and a load of 1.20 kgf, is 2.0 cm. 3 / 10 minutes or more, preferably 4.0cm 3 / 10 minutes or more, further preferably 6.0cm 3 / 10 minutes or more, further preferably 7.5cm 3 / 10 minutes or more, with 15cm being a further preferred size 3 / 10 minutes or more, and preferably 80cm 3 / 10 minutes or less. By setting it to the lower limit or above, there is a tendency to further reduce the delay of the obtained molded article. In addition, by setting it to the upper limit or below, there is a tendency to improve impact resistance.

[0078] In the case where the resin composition of this embodiment contains two or more first polycarbonate resins, it is preferable that the sum of the values ​​obtained by multiplying the MVR of each first polycarbonate resin by its mass fraction is within the range described above.

[0079] The first polycarbonate resin preferably includes at least one of bisphenol A aromatic polycarbonate resin and bisphenol C aromatic polycarbonate resin, and more preferably includes bisphenol A aromatic polycarbonate resin.

[0080] As a bisphenol A type aromatic polycarbonate resin, it is preferable that 90 mol% or more of all structural units are derived from bisphenol A (i.e., 2,2-bis(4-hydroxyphenyl)propane) structural units, and more preferably 95 mol% or more of all structural units are derived from bisphenol A (i.e., 2,2-bis(4-hydroxyphenyl)propane).

[0081] As a bisphenol C type aromatic polycarbonate resin, it is preferable that 90 mol% or more of all structural units are derived from bisphenol C (i.e., 2,2-bis(4-hydroxy-3-methylphenyl)propane) structural units, and more preferably 95 mol% or more of all structural units are derived from bisphenol C.

[0082] On the other hand, the refractive index of the second polycarbonate resin is preferably 1.590 or higher, more preferably 1.605 or higher, even more preferably 1.610 or higher, particularly preferably 1.640 or higher, and preferably 1.700 or lower, more preferably 1.670 or lower, and even more preferably 1.650 or lower. By setting it to the lower limit or higher and the upper limit or lower, the types of polystyrene resins that can be applied increase, and there is a tendency to easily impart the desired properties to the obtained resin composition or molded article.

[0083] The difference in refractive index between the second polycarbonate resin and the styrene resin is greater than 0. In addition, it is preferably 0.100 or less, more preferably 0.080 or less, even more preferably 0.040 or less, and even more preferably 0.030 or less.

[0084] The viscosity-average molecular weight (Mv) of the second polycarbonate resin is preferably 9,000 or more, more preferably 10,000 or more, further preferably 50,000 or less, more preferably 30,000 or less, and even more preferably 25,000 or less. By setting it to the above-mentioned lower limit value or less, there is a tendency to further reduce the delay of the obtained molded article.

[0085] The viscosity-average molecular weight (Mv) of the second polycarbonate resin can be determined by the same method as that used to determine the viscosity-average molecular weight (Mv) of the first polycarbonate resin.

[0086] The second polycarbonate resin is preferably a resin with excellent heat resistance. Specifically, the glass transition temperature of the second polycarbonate resin is preferably 155°C or higher, more preferably 160°C or higher, even more preferably 165°C or higher, and preferably 200°C or lower, more preferably 195°C or lower, and even more preferably 190°C or lower.

[0087] For the glass transition temperature (Tg) of the second polycarbonate resin, as described in the differential scanning calorimetry (DSC) determination conditions below, two cycles of heating and cooling were performed, and the glass transition temperature at the heating point of the second cycle was measured and recorded as the result. The determination conditions were set as follows: starting temperature: 30°C, heating rate: 10°C / min, reaching temperature: 250°C, and cooling rate: 20°C / min.

[0088] The measuring apparatus can be a differential scanning calorimeter (DSC, Hitachi High-Tech Science, “DSC7020”).

[0089] In the case where the resin composition of this embodiment contains two or more second polycarbonate resins, the glass transition temperature is set as the sum of the values ​​obtained by multiplying the glass transition temperature of each polycarbonate resin by its mass fraction.

[0090] As the second polycarbonate resin, it preferably includes at least one selected from bisphenol AP type aromatic polycarbonate resin, bisphenol BP type aromatic polycarbonate resin and fluorene polycarbonate resin, and is particularly more preferably included with bisphenol AP type aromatic polycarbonate resin and / or fluorene polycarbonate resin.

[0091] As a bisphenol AP type aromatic polycarbonate resin, it is preferable that 90 mol% or more of all structural units are derived from the structural unit of bisphenol AP (i.e., 1,1-bis(4-hydroxyphenyl)-1-phenylethane), and more preferably 95 mol% or more of all structural units are derived from this structural unit.

[0092] As a bisphenol BP type aromatic polycarbonate resin, it is preferable that 90 mol% or more of all structural units are derived from bisphenol BP (i.e., 1,1-bis(4-hydroxyphenyl-1,1-diphenylmethane) structural units, and more preferably 95 mol% or more of all structural units are derived from this structural unit.

[0093] As a fluorene polycarbonate resin, it is preferred to be a resin in which 50 mol% or more of all structural units are structural units represented by the following formula (a), more preferably 55 mol% or more of all structural units, further preferably 80 mol% or more, even more preferably 90 mol% or more, and particularly preferably 95 mol% or more of all structural units are such structural units.

[0094] Other structural units constituting fluorene polycarbonate resins include structural units derived from monomers with a bisphenol backbone, such as bisphenol A, bisphenol C, and bisphenol TMC (i.e., 4,4'-(3,3,5-trimethylcyclohexylidene)bisphenol). Furthermore, reference can be made to the structural unit represented by formula (1) described in paragraph 0008 of International Publication No. 2017 / 099226, paragraphs 0043-0052 of International Publication No. 2017 / 099226, and Japanese Patent Application Publication No. 2011-046769, the contents of which are incorporated herein by reference.

[0095] Equation (a)

[0096] [Chemical Formula 1]

[0097]

[0098] The method for manufacturing the first polycarbonate resin and the second polycarbonate resin is not particularly limited, and any known method can be used. Examples include: interfacial polymerization, melt transesterification, pyridine polymerization, ring-opening polymerization of cyclic carbonate compounds, and solid-phase transesterification of prepolymers. Among these, interfacial polymerization and melt transesterification are preferred, and interfacial polymerization is more preferred.

[0099] In the resin composition of this embodiment, the difference in refractive index between the first polycarbonate resin and the second polycarbonate resin is preferably 0.001 or more, more preferably 0.005 or more, even more preferably 0.010 or more, and even more preferably 0.020 or more. It is also preferably 0.100 or less, more preferably 0.080 or less, even more preferably 0.060 or less, and even more preferably 0.040 or less. By setting the value to the lower limit or above, the variety of applicable polystyrene resins increases, and the resulting resin composition or molded article tends to easily acquire the desired properties. Furthermore, by setting the value to the upper limit or below, the compatibility between the first and second polycarbonate resins tends to increase.

[0100] When the difference in SP values ​​(solubility parameter) between the first polycarbonate resin and the second polycarbonate resin is small, the compatibility improves and the transparency becomes better, which is therefore preferable. The difference in SP values ​​between the first polycarbonate resin and the second polycarbonate resin is preferably 2.5 or less, more preferably 2.2 or less.

[0101] The polycarbonate resin used in this embodiment may contain recycled materials.

[0102] Examples of recycled polycarbonate resins include resins obtained through material recycling and resins obtained through chemical recycling (chemical decomposition method). Material recycling involves crushing and cleaning scraps, defective products, and recycled used polycarbonate resin molded products for reuse.

[0103] In the resin composition of this embodiment, relative to a total of 100 parts by weight of the first polycarbonate resin and the second polycarbonate resin, it is preferable to include 50 to 97 parts by weight of the first polycarbonate resin and 3 to 50 parts by weight of the second polycarbonate resin. Relative to a total of 100 parts by weight of the first and second polycarbonate resins, the content of the first polycarbonate resin is preferably 55 parts by weight or more, more preferably 60 parts by weight or more, further preferably 65 parts by weight or more, further preferably 70 parts by weight or more, even more preferably 75 parts by weight or more, further preferably 80 parts by weight or more, 85 parts by weight or more, 87 parts by weight or more, 90 parts by weight or more, and preferably 95 parts by weight or less. By setting it to the lower limit or above, there is a tendency for improved impact resistance. Furthermore, by setting it to the upper limit or below, there is a tendency for the retardation to easily decrease.

[0104] In this embodiment, the first polycarbonate resin preferably comprises bisphenol A type aromatic polycarbonate resin, and the second polycarbonate resin comprises bisphenol AP type aromatic polycarbonate resin and / or fluorene polycarbonate resin.

[0105] The resin composition of this embodiment preferably contains 50% by mass or more of polycarbonate resin (the total of the first polycarbonate resin and the second polycarbonate resin), more preferably 55% by mass or more, and can be 60% by mass or more, 65% by mass or more, 70% by mass or more, 75% by mass or more, or 80% by mass or more, depending on the application, etc. In addition, it is preferably 95% by mass or less, more preferably 90% by mass or less, and even more preferably 85% by mass or less, depending on the application, etc., it can be 80% by mass or less, 78% by mass or less, or 75% by mass or less.

[0106] The resin composition of this embodiment may contain only one first polycarbonate resin and one second polycarbonate resin, or it may contain two or more. When two or more are contained, the total amount is preferably within the range described above.

[0107] <Styrene-based resins>

[0108] The resin composition of this embodiment contains a styrene-based resin. By including a styrene-based resin, low delay can be achieved.

[0109] The refractive index of the styrene-based resin used in this embodiment is preferably 1.571 or higher, more preferably 1.575 or higher, even more preferably 1.580 or higher, and even more preferably 1.585 or higher. It is also preferably 1.699 or lower, more preferably 1.670 or lower, even more preferably 1.640 or lower, and even more preferably 1.610 or lower. By setting it to the above-mentioned upper limit value or lower, there is a tendency to improve impact resistance.

[0110] Examples of styrene-based resins in this embodiment include homopolymers of styrene monomers, copolymers of styrene monomers and monomers capable of copolymerizing with styrene monomers.

[0111] For the styrene-based resin of this embodiment, the styrene monomer unit preferably accounts for 30% or more of all monomer units, more preferably 40% or more of all monomer units, and even more preferably 50% or more of all monomer units.

[0112] The first embodiment of the styrene resin is a styrene resin (i.e., polystyrene resin) in which more than 90% by mass of all monomer units are styrene monomers, preferably more than 95% by mass of all monomer units are styrene monomers, more preferably more than 98% by mass of all monomer units are styrene monomers, and 100% by mass of all monomer units may be styrene monomers.

[0113] A second embodiment of the styrene-based resin comprises a styrene-based resin containing 20-90% by mass of styrene monomer units, 1-30% by mass of maleic anhydride monomer units, and 0-60% by mass of other monomer units (wherein the total of styrene monomer units, maleic anhydride monomer units, and other monomer units does not exceed 100% by mass). In the second embodiment, the total of styrene monomer units and maleic anhydride monomer units is preferably 40% by mass or more, more preferably 50% by mass or more, and can also be 100% by mass. An example of other monomer units is an N-phenylmaleimide monomer unit. Alternatively, monomer units may be derived from monomers listed below among monomers other than styrene monomers.

[0114] Styrene monomers refer to styrene and styrene with substituents, including: styrene, α-methylstyrene, p-methylstyrene, vinylxylene, ethylstyrene, dimethylstyrene, p-tert-butylstyrene, vinylnaphthalene, methoxystyrene, monobromostyrene, dibromostyrene, fluorostyrene, tribromostyrene, etc., more preferably styrene and α-methylstyrene, and particularly preferably styrene.

[0115] In addition, among the monomers constituting styrene-based resins, monomers other than styrene monomers include: (meth)acrylate monomers, maleimide monomers such as (meth)acrylate, N-methylmaleimide, and N-phenylmaleimide, acrylic acid, methacrylic acid, maleic acid anhydride, phthalic acid, itaconic acid, and other α,β-unsaturated carboxylic acids and their anhydrides, and rubber such as butadiene.

[0116] The styrene resin used in this embodiment may or may not include rubber-reinforced polystyrene resin. Preferably, the resin composition of this embodiment does not substantially contain rubber-reinforced styrene resin. "Substantially does not contain" means that the content of rubber-reinforced styrene resin in the resin composition of this embodiment is less than 10% by mass of the total styrene resin content, preferably less than 5% by mass, more preferably less than 3% by mass, and even more preferably less than 1% by mass.

[0117] Specific examples of rubber-reinforced styrene resins include: acrylonitrile-styrene copolymer (AS resin), impact-resistant polystyrene resin (HIPS), acrylonitrile-butadiene-styrene copolymer (ABS resin), acrylonitrile-acrylic rubber-styrene copolymer (AAS resin), acrylonitrile-styrene-acrylic rubber copolymer (ASA resin), acrylonitrile-ethylene-propylene rubber-styrene copolymer (AES resin), and styrene-IPN type rubber copolymer, etc.

[0118] The styrene-based resin used in this embodiment preferably has a weight-average molecular weight of 2000 or more, more preferably 5000 or more, even more preferably 10000 or more, even more preferably 50000 or more, even more preferably 100000 or more, and preferably 500000 or less, more preferably 450000 or less, even more preferably 400000 or less, and even more preferably 350000 or less. Setting the weight-average molecular weight to the lower limit or above tends to improve impact resistance. Furthermore, setting the weight-average molecular weight to the upper limit or below tends to improve transparency.

[0119] The weight-average molecular weight was obtained as follows: using a Tosoh HLC-8320 GPC EcoSEC, tetrahydrofuran as solvent, Shodex KF-G, three KF-805L, and KF-800D columns, at a column temperature of 40°C and a flow rate of 1.2 mL / min, the weight-average molecular weight was determined by GPC (gel permeation chromatography), and the converted polystyrene value was detected by a detector (UV-8320) at a detection wavelength of 254 nm.

[0120] The styrene-based resin used in this embodiment may contain recycled materials.

[0121] Examples of recycled styrene resins include resins obtained through material recycling and resins obtained through chemical recycling (chemical decomposition method). Material recycling involves crushing and cleaning scraps, defective products, and recycled used styrene resin molded products for reuse.

[0122] The content of styrene resin in the resin composition of this embodiment is preferably 5 parts by mass or more, more preferably 10 parts by mass or more, and preferably 100 parts by mass or less, more preferably 90 parts by mass or less, even more preferably 80 parts by mass or less, even more preferably 70 parts by mass or less, even more preferably 50 parts by mass or less, and even more preferably 40 parts by mass or less. By setting it to the lower limit or above, there is a tendency to delay further reduction. In addition, by setting it to the upper limit or below, there is a tendency to improve impact resistance.

[0123] The resin composition of this embodiment may contain only one type of styrene resin, or it may contain two or more types. When two or more types are contained, the total amount is preferably within the range described above.

[0124] Furthermore, the resin composition of this embodiment, relative to a total of 100 parts by mass of 50-97 parts by mass of the first polycarbonate resin and 3-50 parts by mass of the second polycarbonate resin, also includes 5-100 parts by mass of a styrene resin. The first polycarbonate resin includes a bisphenol A type aromatic polycarbonate resin, the second polycarbonate resin includes a bisphenol AP type aromatic polycarbonate resin and / or a fluorene polycarbonate resin, and the styrene resin includes a styrene resin in which more than 90% by mass of all monomer units are styrene monomers, and includes at least one of a styrene resin containing 20-90% by mass of styrene monomer units, 1-30% by mass of maleic anhydride monomer units, and 0-60% by mass of N-phenylmaleimide monomer units. Additionally, the haze when the above resin composition is molded to a thickness of 3 mm is preferably less than 20%. Furthermore, the details of the first polycarbonate resin, the second polycarbonate resin, and the styrene resin are preferably within the same range as those described in the above resin composition section.

[0125] Stabilizer

[0126] The resin composition of this embodiment may contain a stabilizer.

[0127] Examples of stabilizers include heat stabilizers and antioxidants.

[0128] In addition, phenols, amines, phosphorus compounds, and thioethers can be cited as stabilizers. In this embodiment, phosphorus-based heat stabilizers and / or phenolic antioxidants are preferred.

[0129] As a phosphorus-based heat stabilizer, any known phosphorus-based heat stabilizer can be used. Specific examples include: oxyacids of phosphorus such as phosphoric acid, phosphonic acid, phosphorous acid, hypophosphite, and polyphosphonic acid; acidic metal pyrophosphates such as sodium pyrophosphate, potassium pyrophosphate, and calcium pyrophosphate; phosphates of Group 1 or Group 2B metals such as potassium phosphate, sodium phosphate, cesium phosphate, and zinc phosphate; organophosphate compounds, organophosphite compounds, and organophosphonate compounds, with organophosphite compounds being particularly preferred.

[0130] Examples of organophosphite compounds include: triphenyl phosphite, tris(mononophenyl) phosphite, tris(monono / dinonophenyl) phosphite, tris(2,4-di-tert-butylphenyl) phosphite, monooctyl diphenyl phosphite, dioctyl monophenyl phosphite, monodecyl diphenyl phosphite, didecyl monophenyl phosphite, tridecyl phosphite, trilauryl phosphite, tristearyl phosphite, and 2,2-methylene bis(4,6-di-tert-butylphenyl)octyl phosphite.

[0131] Examples of such organophosphite compounds include, for instance: ADEKA STAB 1178, ADEKA STAB 2112, and ADEKA STAB HP-10 manufactured by ADEKA Corporation; JP-351, JP-360, and JP-3CP manufactured by Jōhoku Chemical Industry Co., Ltd.; and Irgafos 168 manufactured by BASF Corporation.

[0132] As a phenolic antioxidant, hindered phenolic antioxidants are preferred.

[0133] Specific examples of hindered phenolic antioxidants include: pentaerythritol tetrakis[3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate], octadecyl 3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate, thiodiethylidene bis[3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate], N,N'-hexane-1,6-dimethylbis[3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionamide], 2,4-dimethyl-6-(1-methylpentadecanyl)phenol, diethyl[[3,5-bis(1,1-dimethylethyl)-4-hydroxyphenyl]methyl]phosphate, 4,6- Bis(octylthiomethyl)o-cresol, ethylene bis(oxyethylene)bis[3-(5-tert-butyl-4-hydroxy-m-tolyl)propionate], hexamethylene bis[3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate], 1,3,5-tris(3,5-di-tert-butyl-4-hydroxybenzyl)-1,3,5-triazine-2,4,6(1H,3H,5H)-trione, 2,6-di-tert-butyl-4-(4,6-bis(octylthio)-1,3,5-triazine-2-ylamino)phenol, 2-[1-(2-hydroxy-3,5-di-tert-pentylphenyl)ethyl]-4,6-di-tert-pentylphenyl acrylate, etc.

[0134] Among them, pentaerythritol tetrakis[3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate] and octadecyl 3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate are preferred. Specifically, examples of such hindered phenolic antioxidants include: BASF's "Irganox 1010" and "Irganox 1076", and ADEKA's "ADEKA STAB AO-50" and "ADEKA STAB AO-60".

[0135] The stabilizer content in the resin composition of this embodiment is typically 0.001 parts by mass or more, preferably 0.005 parts by mass or more, and more preferably 0.01 parts by mass or more, relative to the total 100 parts by mass of the first polycarbonate resin and the second polycarbonate resin. It is also typically 1 part by mass or less, preferably 0.5 parts by mass or less, and more preferably 0.3 parts by mass or less. By setting the stabilizer content within the above range, the effect of adding the stabilizer can be more effectively achieved.

[0136] The resin composition of this embodiment may contain only one stabilizer or two or more stabilizers. When two or more stabilizers are contained, the total amount is preferably within the range described above.

[0137] <Mold Release Agent>

[0138] The resin composition of this embodiment may contain a release agent.

[0139] Examples of release agents include: aliphatic carboxylic acids, salts of aliphatic carboxylic acids, esters formed from aliphatic carboxylic acids and alcohols, aliphatic hydrocarbon compounds with a number average molecular weight of 200 to 15,000, polysiloxane silicone oils, ketone waxes, light amides, etc., preferably aliphatic carboxylic acids, salts of aliphatic carboxylic acids, esters formed from aliphatic carboxylic acids and alcohols, and more preferably esters formed from aliphatic carboxylic acids and alcohols.

[0140] Examples of esters formed from aliphatic carboxylic acids and alcohols include: saturated or unsaturated mono- or di-aliphatic carboxylic acid esters, glycerol fatty acid esters, sorbitan fatty acid esters, and their partial saponifications. Among these, mono- or di-fatty acid esters composed of fatty acids with 11 to 28 carbon atoms, more preferably 17 to 21 carbon atoms, and alcohols are preferred.

[0141] Examples of fatty acids include: palmitic acid, stearic acid, hexanoic acid, decanoic acid, lauric acid, arachidic acid, behenic acid, tetracosanoic acid, ceric acid (hexacosanoic acid), triacontanic acid, tritetracosanoic acid, linalic acid, adipic acid, and azelaic acid. Additionally, fatty acids can be alicyclic.

[0142] Examples of alcohols include saturated or unsaturated monohydric or polyhydric alcohols. These alcohols may have substituents such as fluorine atoms or aryl groups. Among them, monohydric or polyhydric saturated alcohols with 30 or fewer carbon atoms are preferred, and aliphatic saturated monohydric or polyhydric alcohols with 30 or fewer carbon atoms are more preferred. Here, aliphatic also includes alicyclic compounds.

[0143] Specific examples of such alcohols include: octanol, decanol, dodecylol, stearyl alcohol, behenol, ethylene glycol, diethylene glycol, glycerol, pentaerythritol, 2,2-dihydroxyperfluoropropanol, neopentyl glycol, bis(trimethylolpropane), dipentaerythritol, etc.

[0144] It should be noted that the above-mentioned ester compounds may contain aliphatic carboxylic acids and / or alcohols as impurities, or may be a mixture of multiple compounds.

[0145] Specific examples of fatty acid ester compounds include: glyceryl monostearate, glyceryl monostearate, glyceryl distearate, glyceryl-12-hydroxy monostearate, sorbitan monostearate, pentaerythritol monostearate, pentaerythritol distearate, pentaerythritol tetrastearate, stearate, ethylene glycol lignite, etc.

[0146] In addition to the above, for details regarding the release agent, please refer to paragraphs 0055 to 0060 of Japanese Patent Application Publication No. 2018-095706 and paragraphs 0106 to 0115 of Japanese Patent Application Publication No. 2015-117298, which are incorporated herein by reference.

[0147] When the resin composition of this embodiment contains a release agent, its content is preferably 0.001 to 3 parts by mass relative to the total of 100 parts by mass of the first polycarbonate resin and the second polycarbonate resin, more preferably 0.005 to 0.8 parts by mass.

[0148] The resin composition of this embodiment may contain only one type of release agent, or it may contain two or more types. When two or more types are contained, the total amount is preferably within the range described above.

[0149] <Other Ingredients>

[0150] The resin composition of this embodiment may further include components other than those described above. Examples of other components include: reinforcing materials, colorants, flame retardants, flame retardant additives, ultraviolet absorbers, fluorescent whitening agents, impact resistance modifiers, epoxy compounds, antifogging agents, flowability modifiers, plasticizers, dispersants, antibacterial agents, antiviral agents, etc. Details of these components can be found in Japanese Patent Application Publication No. 2014-136710, paragraphs 0107-0115; Japanese Patent Application Publication No. 2015-117298, paragraphs 0106-0128; Japanese Patent Application Publication No. 2018-095706, paragraphs 0055-0061; and International Publication No. 2021 / 241471, paragraphs 0047-0103, which are incorporated herein by reference.

[0151] When the other components mentioned above are present, the content of the resin composition is, for example, 0.001% by mass or more, and preferably 5.0% by mass or less, more preferably 3.0% by mass or less, and more preferably 1.0% by mass or less, based on the mass of the resin composition.

[0152] For the resin composition of this embodiment, the total amount of the first polycarbonate resin, the second polycarbonate resin, and the styrene resin preferably accounts for 95% or more by mass of the resin composition, more preferably 97% or more by mass, and even more preferably 98% or more by mass.

[0153] Furthermore, for the resin composition of this embodiment, the total amount of the first polycarbonate resin, the second polycarbonate resin, the styrene resin, the release agent, and the stabilizer preferably accounts for 96% or more by mass of the resin composition, more preferably 98% or more by mass, and even more preferably 99% or more by mass.

[0154] <Physical Properties of Resin Compositions>

[0155] The resin composition of this embodiment preferably has excellent transparency.

[0156] Specifically, the total light transmittance of the test piece when the resin composition of this embodiment is molded to a thickness of 3 mm is preferably 85% or more, more preferably 87% or more, and can be 100% or less or 99% or less.

[0157] Furthermore, when the resin composition of this embodiment is molded to a thickness of 3 mm, the haze is less than 20%, preferably 19% or less, more preferably 18% or less, even more preferably 10% or more, even more preferably 7% or less, and even more preferably 5% or less. Regarding the lower limit, it is preferably 0% or more, and practically 0.1% or more.

[0158] Such excellent transparency can be achieved by bringing the refractive index difference between polycarbonate resin and styrene-based resin closer together. For example, when the refractive index of styrene-based resin is 1.589 and the refractive index of bisphenol A aromatic polycarbonate resin is 1.582, although there is a difference in refractive index between polycarbonate resin and styrene-based resin, by making bisphenol A aromatic polycarbonate resin and / or fluorene polycarbonate resin with higher refractive index compatible, the refractive index of the polycarbonate resin phase after the first and second blends can be brought closer to that of styrene-based resin, thereby improving the overall transparency of the resin composition.

[0159] Furthermore, the YI value (Yellow Index) of the resin composition of this embodiment molded into a test piece with a thickness of 3 mm is preferably 20 or less, more preferably 19 or less, even more preferably 15 or less, even more preferably 10 or less, even more preferably 7 or less, even more preferably 5 or less, and preferably 0 or more. Even if it is 1 or more, the required performance can be met.

[0160] The resin composition of this embodiment is preferably low-retardation. Specifically, the average retardation value when the resin composition is molded into a test piece with a thickness of 2 mm is preferably less than 700 nm, more preferably 650 nm or less, even more preferably 600 nm or less, even more preferably 500 nm or less, even more preferably 450 nm or less, even more preferably 400 nm or less, and further preferably 350 nm or less, 330 nm or less, or 300 nm or less. The lower limit of the above-mentioned average retardation value is preferably 0 nm or more, and even 50 nm or more, and even more preferably 100 nm or more, can meet the required performance.

[0161] The total light transmittance, haze, YI value, and average delay value were measured according to the description in the embodiments described later.

[0162] <Method for manufacturing resin composition>

[0163] The resin composition of this embodiment can be manufactured using conventional manufacturing methods for resin compositions comprising thermoplastic resins. For example, it can be obtained by melt-blending a first polycarbonate resin, a second polycarbonate resin, and a styrene-based resin. One form formed from such a resin composition is granules.

[0164] The components can be pre-mixed and fed to the extruder all at once, or they can be partially pre-mixed and then fed to the extruder using a feeder. The extruder can be a single-screw extruder or a twin-screw extruder.

[0165] In addition, when using reinforcing materials such as glass fiber, it is preferable to supply the material from a side feeder in the middle of the extruder barrel.

[0166] The heating temperature during melt mixing can usually be appropriately selected from the range of 150~350℃.

[0167] <Manufacturing Methods for Molded Articles>

[0168] The molded article is formed from the resin composition or particles of this embodiment.

[0169] There are no particular restrictions on the shape of the molded product. It can be appropriately selected according to the purpose and use of the molded body. For example, the shapes that can be given are: film, rod, cylinder, ring, circle, oval, polygon, irregular shape, hollow, frame, box, panel, button, etc.

[0170] The manufacturing method of the molded article in this embodiment is not particularly limited, and any molding method commonly used for resin compositions containing thermoplastic resins can be employed. Examples include: injection molding, high-speed injection molding, injection compression molding, two-color molding, gas-assisted blow molding, molding using insulated molds, molding using rapidly heated molds, foaming molding (including supercritical fluids), insert molding, IMC (in-mold coating) molding, extrusion molding, sheet molding, thermoforming, rotational molding, lamination molding, stamping, and blow molding, among which injection molding and extrusion molding are preferred. When manufacturing a film by extrusion molding, film-forming properties can be improved by increasing the molecular weight of the polycarbonate resin.

[0171] <Applications>

[0172] The molded articles of this embodiment can be widely used in molded articles containing thermoplastic resins, especially for applications requiring transparency and low delay.

[0173] Specifically, these are shaped optical components, and more specifically, various lenses. Examples of preferred applications include: lenses for various cameras, telescopes, microscopes, projectors, optical measuring devices, etc.; in-vehicle display devices for various optical discs, home televisions, personal computer monitors, car navigation systems, car audio systems, etc.; and panel components and films for display devices used in smartphones, head-mounted displays, barcode readers, scanners, etc. They are particularly suitable for panel components in display devices used in smartphones and other portable terminals, tablets, car navigation systems, car audio systems, portable game consoles, digital cameras, etc., and are especially suitable as front components of display devices. They are even more suitable as lenses for various cameras, telescopes, microscopes, projectors, optical measuring devices, etc.

[0174] Example

[0175] The present invention will be described in more detail below with examples. The materials, amounts, proportions, processing contents, processing steps, etc., shown in the following examples can be appropriately modified without departing from the spirit of the invention. Therefore, the scope of the present invention is not limited to the specific examples shown below.

[0176] In cases where the measuring equipment used in the embodiments is difficult to obtain due to production stoppages, other equipment with equivalent performance can be used for measurement.

[0177] 1. Raw materials

[0178] The raw materials shown in Table 1 were used.

[0179]

[0180] <Determination of Refractive Index>

[0181] The refractive index of polycarbonate resin and styrene resin was determined according to JIS K7142 under the conditions of temperature 23±1℃, humidity 50±5%RH, and sodium D line 589nm.

[0182] 2. Examples 1-29, Comparative Examples 1-7

[0183] <Mixture>

[0184] The components listed in Table 1 were mixed uniformly using a rotary drum mixer in the proportions (all expressed in parts by mass) shown in Tables 2-7. This mixture was then fed into a twin-screw extruder (Shibaura Machinery Co., Ltd., "TEX26SX") and compounded at a screw speed of 150 rpm, a discharge rate of 20 kg / h, and a barrel temperature of 280°C. The extrudate was extruded as a filament from the extrusion nozzle. The extrudate was rapidly cooled in a water bath and granulated using a granulator to obtain granules of the resin composition.

[0185] <Optical Properties>

[0186] The resin compositions obtained above were injection molded using a Sumitomo Heavy Industries SE100DU injection molding machine at a resin temperature of 280°C and a mold temperature of 80°C to form two-stage stepped plates (2 mm thick and 3 mm thick).

[0187] For the 3mm thick portion of the obtained second-level stepped plate, the total light transmittance (unit: %) and haze (unit: %) were measured.

[0188] The total light transmittance and haze were measured using a haze meter according to ASTM-D1003 with a D65 light source.

[0189] As a haze meter, the "NDH4000" (trade name) manufactured by Nippon Denshoku Kogyo Co., Ltd. was used.

[0190] In addition, for the 3mm thick portion of the second-level stepped plate, the YI value (Yellow Index) was measured using the transmission method with a C light source and a 2° field of view.

[0191] The spectrophotometer used was the SE6000 manufactured by Nippon Denshoku Kogyo Co., Ltd.

[0192] <Delay>

[0193] The resin compositions obtained above were injection molded using a Sumitomo Heavy Industries SE100DU injection molding machine at a resin temperature of 280°C and a mold temperature of 80°C to produce a product with an area of ​​100 mm².2 A test piece with a thickness of 2 mm.

[0194] Using a wide-range two-dimensional birefringence evaluation device (Photonic Lattice "WPA-200-L"), the area of ​​100 mm² obtained above was evaluated by three wavelength measurements (523 nm, 543 nm, 575 nm). 2 The phase difference of the entire 2mm thick test piece was analyzed by region, and its average value (average delay, unit: nm) was obtained.

[0195]

[0196]

[0197]

[0198]

[0199]

[0200]

[0201] In the table above, the proportions (parts by mass) of C1 to C8 represent the amount (parts by mass) of styrene resin added relative to a total of 100 parts by mass of the first polycarbonate resin (A1 to A3) and the second polycarbonate resin (B1 to B3). Similarly, the proportions (parts by mass) of B1 to B3 represent the amount (parts by mass) of the second polycarbonate resin added relative to a total of 100 parts by mass of the first and second polycarbonate resins.

[0202] Based on the above results, it is clear that the resin composition of the present invention can provide molded articles with low delay and excellent transparency (Examples 1-29). Furthermore, the YI value is also low (Examples 1-29).

[0203] In contrast, the molded articles obtained from the resin compositions of the comparative examples had high delay or poor transparency (Comparative Examples 1-7).

Claims

1. A resin composition comprising a first polycarbonate resin, a second polycarbonate resin, and a styrene-based resin, wherein, The refractive indices of the first polycarbonate resin, the second polycarbonate resin, and the styrene resin satisfy the following condition: refractive index of the first polycarbonate resin < refractive index of the styrene resin < refractive index of the second polycarbonate resin. The haze of the resin composition when molded to a thickness of 3 mm is less than 20%.

2. The resin composition according to claim 1, wherein 5 to 100 parts by weight of styrene resin are contained in 100 parts by weight of the first polycarbonate resin and the second polycarbonate resin.

3. The resin composition according to claim 1 or 2, wherein, The refractive index of the first polycarbonate resin is greater than 1.570 and less than 1.

590.

4. The resin composition according to claim 1 or 2, wherein, The first polycarbonate resin comprises a bisphenol A type aromatic polycarbonate resin.

5. The resin composition according to claim 1 or 2, wherein, The refractive index of the second polycarbonate resin is 1.590~1.

700.

6. The resin composition according to claim 1 or 2, wherein, The second polycarbonate resin comprises bisphenol AP type aromatic polycarbonate resin.

7. The resin composition according to claim 1 or 2, wherein, The second polycarbonate resin comprises fluorene polycarbonate resin.

8. The resin composition according to claim 1 or 2, wherein, The refractive index of the styrene-based resin is 1.571~1.

699.

9. The resin composition according to claim 1 or 2, comprising at least one of a styrene resin containing more than 90% by mass of styrene monomers of all monomer units, and a styrene resin containing 20-90% by mass of styrene monomer units, 1-30% by mass of maleic anhydride monomer units, and 0-60% by mass of N-phenylmaleimide monomer units.

10. The resin composition according to claim 1 or 2, wherein, The styrene resin is a styrene resin in which more than 90% by mass of all monomer units are styrene monomers.

11. The resin composition according to claim 1 or 2, wherein 100 parts by weight of the first polycarbonate resin and the second polycarbonate resin comprise 50 to 97 parts by weight of the first polycarbonate resin and 3 to 50 parts by weight of the second polycarbonate resin.

12. The resin composition according to claim 1, wherein, The content of the styrene resin is less than 90 parts by mass relative to the total of 100 parts by mass of the first polycarbonate resin and the second polycarbonate resin, and the refractive index of the second polycarbonate resin is 1.590~1.

700.

13. The resin composition according to claim 1, wherein, The content of the styrene resin is less than 90 parts by mass relative to the total of 100 parts by mass of the first polycarbonate resin and the second polycarbonate resin. The styrene resin is a styrene resin in which more than 90% by mass of all monomer units are styrene monomers.

14. The resin composition according to claim 1, wherein 100 parts by weight of the first polycarbonate resin and the second polycarbonate resin comprise 5 to 100 parts by weight of a styrene-based resin. The refractive index of the first polycarbonate resin is greater than 1.570 and less than 1.

590. The first polycarbonate resin comprises a bisphenol A type aromatic polycarbonate resin. The refractive index of the second polycarbonate resin is 1.590~1.

700. The second polycarbonate resin comprises bisphenol AP type aromatic polycarbonate resin and / or fluorene polycarbonate resin. The refractive index of the styrene-based resin is 1.571~1.

699. The styrene resin is a styrene resin in which styrene monomer units account for 90% by mass of all monomer units.

15. A resin composition comprising 5 to 100 parts by weight of a styrene resin relative to a total of 50 to 97 parts by weight of a first polycarbonate resin and 3 to 50 parts by weight of a second polycarbonate resin. The first polycarbonate resin comprises a bisphenol A type aromatic polycarbonate resin. The second polycarbonate resin comprises bisphenol AP type aromatic polycarbonate resin and / or fluorene polycarbonate resin, the styrene resin comprises styrene resin in which more than 90% by mass of all monomer units are styrene monomers, and at least one of styrene resins containing 20-90% by mass of styrene monomer units, 1-30% by mass of maleic anhydride monomer units and 0-60% by mass of N-phenylmaleimide monomer units, and the haze of the resin composition when molded to a thickness of 3 mm is less than 20%.

16. A particle, which is a particle of the resin composition according to claim 1, 2, 12, 13, 14 or 15.

17. A molded article formed from the resin composition of claim 1, 2, 12, 13, 14 or 15.

18. A molded article formed from the particles of claim 16.

19. A lens formed from the resin composition of claim 1, 2, 12, 13, 14 or 15.

20. A lens formed from the particles of claim 16.

Images