Resin composition, particles, molded article, and method for producing resin composition

Abstract

A resin composition that does not substantially contain a fluoropolymer, contains a polycarbonate resin and a flame retardant, and the polycarbonate resin contains a regenerated polycarbonate resin. The invention provides pellets, a molded article, and a method for producing a resin composition.

Description

Technical Field

[0001] The present invention relates to a resin composition, pellets, a molded article, and a method for producing a resin composition. In particular, it relates to a resin composition mainly composed of a polycarbonate resin. Background Art

[0002] The polycarbonate resin is excellent in mechanical strength, electrical properties, transparency, etc., and is widely used as an engineering plastic in various fields such as the field of electrical and electronic equipment and the automotive field. The polycarbonate resin material sometimes requires flame retardancy depending on the use.

[0003] Here, Patent Document 1 describes a resin composition having excellent flame retardancy. Specifically, Patent Document 1 discloses a polycarbonate resin composition containing 5 to 30 parts by mass of a fluidity modifier (B), 3 to 20 parts by mass of a phosphorus-based flame retardant (C), 0.05 to 2 parts by mass of a fluoropolymer (D), 10 to 100 parts by mass of an inorganic filler containing a plate-like inorganic filler (E), and 0.1 to 1 part by mass of an antioxidant (G) having an acyclic alkoxy group with 10 or more carbon atoms in the structure, based on 100 parts by mass of the polycarbonate resin (A).

[0004] Prior Art Documents

[0005] Patent Documents

[0006] Patent Document 1: Japanese Patent Application Laid-Open No. 2021-187863 Summary of the Invention

[0007] Here, with the diversification of the uses of polycarbonate resins, a new polycarbonate resin composition having excellent flame retardancy is required. In particular, a resin composition that can provide a polycarbonate resin molded article having excellent flame retardancy and transparency, etc. is needed.

[0008] An object of the present invention is to solve the above problems, and an object is to provide a resin composition containing a polycarbonate resin having excellent flame retardancy and transparency, as well as pellets, a molded article, and a method for producing a resin composition.

[0009] The present inventors conducted research based on the above problems, and as a result, found that by using a recycled polycarbonate resin as the polycarbonate resin and using a flame retardant, and substantially not using a fluoropolymer, the above problems can be solved.

[0010] Specifically, the above problems are solved by the following means.

[0011] <1> A resin composition containing a polycarbonate resin and a flame retardant,

[0012] The above polycarbonate resin contains a recycled polycarbonate resin,

[0013] Substantially free of fluoropolymers,

[0014] The ratio of the viscosity-average molecular weight (Mv) of the recycled polycarbonate resin (A-1) to the viscosity-average molecular weight (Mv) of the polycarbonate resin (A-2) having the highest viscosity-average molecular weight among the resin compositions, i.e., [Mv(A-1)] / [Mv(A-2)], is 0.9 or less.

[0015] <2>A resin composition comprising a polycarbonate resin and a flame retardant,

[0016] The polycarbonate resin described above contains a recycled polycarbonate resin,

[0017] Substantially free of fluoropolymers,

[0018] The content of the flame retardant is less than 25 parts by mass relative to 100 parts by mass of the polycarbonate resin.

[0019] <3>The resin composition according to <1> or <2>, wherein the flame retardant comprises a metal salt-based flame retardant.

[0020] <4>The resin composition according to <1> or <2>, wherein the flame retardant comprises an alkali metal salt of sulfonic acid.

[0021] <5>The resin composition according to any one of <1> to <4>, wherein the flame retardant comprises a phosphorus-based flame retardant.

[0022] <6>The resin composition according to any one of <1> to <4>, wherein the flame retardant comprises a phosphazene compound.

[0023] <7>The resin composition according to any one of <1> to <6>, wherein the flame retardant is a solid flame retardant.

[0024] <8>The resin composition according to any one of <1> to <7>, wherein the recycled polycarbonate resin contains a structural unit represented by formula (1).

[0025] Formula (1)

[0026]

[0027] (In formula (1), X 1 represents any one of the following structural formulas,

[0028]

[0029] R 3 and R 4Each independently represents a hydrogen atom or a methyl group, and Z represents a group that forms an alicyclic hydrocarbon having 6 to 12 carbon atoms which may have a substituent by bonding to C.)

[0030] <9> The resin composition according to any one of <1> to <8>, wherein a virgin polycarbonate resin is further contained,

[0031] The above virgin polycarbonate resin contains a structural unit represented by formula (1).

[0032] Formula (1)

[0033]

[0034] (In formula (1), X 1 represents any of the following structural formulas,

[0035]

[0036] R 3 and R 4 Each independently represents a hydrogen atom or a methyl group, and Z represents a group that forms an alicyclic hydrocarbon having 6 to 12 carbon atoms which may have a substituent by bonding to C.)

[0037] <10> The resin composition according to any one of <1> to <9>, wherein a virgin polycarbonate resin is further contained,

[0038] The above virgin polycarbonate resin contains a structural unit represented by formula (2).

[0039] Formula (2)

[0040]

[0041] (In formula (2), R 1 represents a methyl group, R 2 represents a hydrogen atom or a methyl group, X 1 represents any of the following structural formulas,

[0042]

[0043] R 3 and R 4 Each independently represents a hydrogen atom or a methyl group, and Z represents a group that forms an alicyclic hydrocarbon having 6 to 12 carbon atoms which may have a substituent by bonding to C.)

[0044] <11> The resin composition according to any one of <1> to <10>, wherein the content of the above polycarbonate resin in the resin composition is 10 to 95% by mass,

[0045] The content of the above-mentioned flame retardant is 0.005 parts by mass or more relative to 100 parts by mass of the polycarbonate resin.

[0046] <12>The resin composition according to any one of <1> to <11>, wherein the mass ratio of the above-mentioned recycled polycarbonate resin (A-1) to the polycarbonate resin (A-2) having the highest viscosity-average molecular weight contained in the above-mentioned resin composition is 10:90 to 90:10.

[0047] <13>The resin composition according to any one of <1> to <12>, wherein the above-mentioned flame retardant contains an alkali metal salt of sulfonic acid and / or a phosphazene compound.

[0048] The above-mentioned flame retardant is a solid flame retardant.

[0049] The above-mentioned recycled polycarbonate resin contains a structural unit represented by the formula (1).

[0050] It further contains a virgin polycarbonate resin.

[0051] The above-mentioned virgin polycarbonate resin contains a structural unit represented by the formula (1) and / or a structural unit represented by the formula (2).

[0052] The content of the above-mentioned polycarbonate resin in the resin composition is 10 to 95% by mass.

[0053] The content of the above-mentioned flame retardant is 0.005 parts by mass or more relative to 100 parts by mass of the polycarbonate resin.

[0054] The mass ratio of the above-mentioned recycled polycarbonate resin (A-1) to the polycarbonate resin (A-2) having the highest viscosity-average molecular weight contained in the above-mentioned resin composition is 10:90 to 90:10.

[0055] Formula (1)

[0056]

[0057] (In the formula (1), X 1 represents any one of the following structural formulas,

[0058]

[0059] R 3 and R 4 each independently represent a hydrogen atom or a methyl group, and Z represents a group that forms an alicyclic hydrocarbon having 6 to 12 carbon atoms that may have a substituent by bonding to C.)

[0060] Formula (2)

[0061]

[0062] (In formula (2), R 1 represents a methyl group, R 2 represents a hydrogen atom or a methyl group, X 1 represents any of the following structural formulas,

[0063]

[0064] R 3 and R 4 each independently represent a hydrogen atom or a methyl group, and Z represents a group that forms an alicyclic hydrocarbon having 6 to 12 carbon atoms that may have substituents by bonding to C.)

[0065] <14> Granules of the resin composition according to any one of <1> to <13>.

[0066] <15> A molded article obtained by molding the resin composition according to any one of <1> to <13>.

[0067] <16> A molded article obtained by molding the granules according to <14>.

[0068] <17> A method for producing a resin composition that substantially does not contain a fluoropolymer, the production method including the steps of melt-kneading a recycled polycarbonate resin (A-1), a polycarbonate resin (A-2), and a flame retardant,

[0069] The ratio of the viscosity-average molecular weight (Mv) of the recycled polycarbonate resin (A-1) to the viscosity-average molecular weight (Mv) of the polycarbonate resin (A-2), i.e., [Mv(A-1)] / [Mv(A-2)], is 0.9 or less.

[0070] According to the present invention, it is possible to provide a resin composition containing a polycarbonate resin, which has excellent flame retardancy and excellent transparency, as well as granules, molded articles, and a method for producing a resin composition. Detailed Embodiments

[0071] Hereinafter, the mode for carrying out the present invention (hereinafter, simply referred to as "the present embodiment") will be described in detail. It should be noted that the following present embodiment is an exemplification for explaining the present invention, and the present invention is not limited to the present embodiment.

[0072] It should be noted that in this specification, "~" is used in the sense of including the numerical values described before and after it as the lower limit value and the upper limit value.

[0073] In this specification, unless otherwise specified, various physical property values and characteristic values are values at 23°C.

[0074] When the measurement methods and the like described in this specification vary from year to year, unless otherwise specified, the measurement methods are based on the standards as of January 1, 2022.

[0075] The resin composition of the present embodiment is characterized by containing a polycarbonate resin and a flame retardant. The polycarbonate resin contains a recycled polycarbonate resin and substantially does not contain a fluoropolymer. The ratio of the viscosity-average molecular weight (Mv) of the recycled polycarbonate resin (A-1) to the viscosity-average molecular weight (Mv) of the polycarbonate resin (A-2) having the highest viscosity-average molecular weight contained in the above resin composition, that is, [Mv(A-1)] / [Mv(A-2)], is 0.9 or less.

[0076] By adopting such a configuration, a resin composition with excellent flame retardancy can be provided. In particular, even without adding a fluoropolymer known as a drip retardant having fibril-forming ability, excellent flame retardancy can be achieved.

[0077] If a heat source is applied to a molded article of polycarbonate resin, the polycarbonate resin undergoes thermal decomposition under the action of the heat source and generates gas. If gas is generated, it burns as a combustible gas, and the heat is transferred to the molded article, further causing combustion. Therefore, when attempting to make a molded article of polycarbonate resin flame retardant, the above cycle can be stopped at a certain stage. It is speculated that in the present embodiment, the formation of a carbonized layer on the molded article during combustion is promoted, thereby preventing heat transfer.

[0078] More specifically, during the combustion of the polycarbonate resin, the polycarbonate resin undergoes various multi-stage reactions including isomerization and finally forms a carbonized layer, thereby preventing the above combustion cycle. Here, it is considered that the recycled polycarbonate resin has already undergone isomerization, and compared with the virgin polycarbonate resin, the reaction time to form a carbonized layer can be shortened.

[0079] In addition, by using a metal salt-based flame retardant as the flame retardant, the amount of the flame retardant added can be reduced.

[0080] Furthermore, in order to reduce the number of drips, a drip retardant (for example, a fluoropolymer having fibril-forming ability) can be added, but when the drip retardant is added, the haze of the resin composition or the molded article will increase. In the present embodiment, even without adding a drip retardant, the number of drips can be reduced, thus improving the transparency of the resin composition or the molded article.

[0081] <Polycarbonate Resin>

[0082] The polycarbonate resin contains a recycled polycarbonate resin. By containing the recycled polycarbonate resin, the flame retardancy can be improved.

[0083] Recycled polycarbonate resin refers to polycarbonate resin that has been reprocessed in some way from virgin polycarbonate resin, including not only recycled products but also defective products of polycarbonate resin molded articles, scraps generated during the manufacture of polycarbonate resin molded articles, defective products of composite products, and removed products, etc. As molded processed products, they mainly include injection molded articles, extrusion molded articles, and molded articles formed by other manufacturing methods.

[0084] As recycled polycarbonate resin, in addition, there can be mentioned recycled polycarbonate resin obtained by material recycling, which is obtained by pulverizing, alkali washing, and reusing in fibers, etc., the recycled polycarbonate resin obtained by chemical recycling (chemical decomposition method), and the recycled polycarbonate resin obtained by mechanical recycling, etc.

[0085] Chemical recycling is a method of chemically decomposing the recycled used polycarbonate resin molded article, restoring it to the raw material level, and resynthesizing polycarbonate resin. On the other hand, mechanical recycling is a method that can reliably remove the contamination of the polycarbonate resin molded article compared to material recycling by performing the alkali washing in the above material recycling more strictly or performing vacuum drying at a high temperature, etc.

[0086] For example, after removing foreign substances from the used polycarbonate resin molded article, it is pulverized and washed, and then pelletized using an extruder to obtain recycled polycarbonate resin.

[0087] Examples of the used polycarbonate resin molded article include optical discs, sheets (including films), instrument covers, headlamp lenses, bottles, and preferably headlamp lenses and / or bottles.

[0088] In addition, the recycled polycarbonate resin is not particularly limited as long as it contains a -[O-R-OC(=O)]- unit (R is an organic group, preferably a hydrocarbon group, more preferably an aliphatic group, an aromatic group, or a group containing both an aliphatic group and an aromatic group, and further having a linear structure or a branched structure) containing a carbonate bond in the molecular main chain. In this embodiment, the recycled polycarbonate resin is preferably an aromatic polycarbonate resin, more preferably a polycarbonate resin having a bisphenol skeleton, and further preferably a bisphenol A type polycarbonate resin. By using such a recycled polycarbonate resin, more excellent heat resistance and toughness can be achieved.

[0089] In this embodiment, the recycled polycarbonate resin is preferably a recycled polycarbonate resin containing a structural unit represented by formula (1) and / or a structural unit represented by formula (2) described later, more preferably a polycarbonate resin containing the structural unit represented by formula (1) in a proportion of 90 mol% or more of all the structural units, and further preferably a polycarbonate resin containing the structural unit represented by formula (1) in a proportion of 95 mol% or more of all the structural units.

[0090] Formula (1)

[0091]

[0092] (In Formula (1), X 1 represents any of the following structural formulas,

[0093]

[0094] R 3 and R 4 each independently represent a hydrogen atom or a methyl group, and Z represents a group that forms an alicyclic hydrocarbon having 6 to 12 carbon atoms which may have substituents by bonding to C.)

[0095] In Formula (1), when X 2 is R 3 and R 4 are preferably at least one being a methyl group, and more preferably both being methyl groups.)

[0096] In addition, when X 2 is Z bonds to the carbon C bonded to two phenyl groups in the above Formula (1) to form a divalent alicyclic hydrocarbon group having 6 to 12 carbon atoms. As the divalent alicyclic hydrocarbon group, for example, cyclohexylidene, cycloheptylidene, cyclododecylidene, adamantylidene, cyclododecylidene and other cycloalkylidene groups can be cited. As the substituted group, groups having a methyl substituent, an ethyl substituent, etc. thereof can be cited. Among these, cyclohexylidene, a methyl-substituted body of cyclohexylidene (preferably a 3,3,5-trimethyl-substituted body), cyclododecylidene are preferred.)

[0097] In Formula (1), X 2 is preferably the following structure.)

[0098]

[0099] In this embodiment, the recycled polycarbonate resin containing the structural unit represented by Formula (1) may contain only 1 kind of the structural unit represented by Formula (1), or may contain 2 or more kinds.)

[0100] The recycled polycarbonate resin containing the structural unit represented by Formula (1) preferably contains the unit represented by Formula (1) in a proportion of 50 mol% or more of all the structural units, more preferably 60 mol% or more, still more preferably 70 mol% or more, and depending on the use, etc., it can be 80 mol% or more, 90 mol% or more, 95 mol% or more, and in addition, it is preferably 100 mol% or less.)

[0101] In the present embodiment, the recycled polycarbonate resin may contain other structural units in addition to the structural units represented by the formula (1). Examples of the other structural units include the structural units derived from the following dihydroxy compounds.

[0102] Bis(4-hydroxyphenyl)methane, 2,2-bis(4-hydroxyphenyl)butane, 2,2-bis(4-hydroxyphenyl)pentane, 2,2-bis(4-hydroxyphenyl)-4-methylpentane, 2,2-bis(4-hydroxy-3-methylphenyl)propane, 2,2-bis(4-hydroxy-3,5-dimethylphenyl)propane, 2,2-bis(4-hydroxy-3-(1-methylethyl)phenyl)propane, 2,2-bis(4-hydroxy-3-tert-butylphenyl)propane, 2,2-bis(4-hydroxy-3-(1-methylpropyl)phenyl)propane, 2,2-bis(4-hydroxy-3-cyclohexylphenyl)propane, 2,2-bis(4-hydroxy-3-phenylphenyl)propane, 1,1-bis(4-hydroxyphenyl)decane, 1,1-bis(4-hydroxyphenyl)cyclohexane, 1,1-bis(4-hydroxyphenyl)-1-phenylethane, 1,1-bis(4-hydroxyphenyl)phenylmethane, 1,1-bis(4-hydroxy-3-methylphenyl)cyclohexane, 1,1-bis(4-hydroxy-3,5-dimethylphenyl)cyclohexane, 1,1-bis(4-hydroxy-3-(1-methylethyl)phenyl)cyclohexane, 1,1-bis(4-hydroxy-3-tert-butylphenyl)cyclohexane, 1,1-bis(4-hydroxy-3-(1-methylpropyl)phenyl)cyclohexane, 1,1-bis(4-hydroxy-3-cyclohexylphenyl)cyclohexane, 1,1-bis(4-hydroxy-3-phenylphenyl)cyclohexane, 1,1-bis(4-hydroxy-3-methylphenyl)-1-phenylethane, 1,1-bis(4-hydroxy-3,5-dimethylphenyl)-1-phenylethane, 1,1-bis(4-hydroxy-3-(1-methylethyl)phenyl)-1-phenylethane, 1,1-bis(4-hydroxy-3-tert-butylphenyl)-1-phenylethane, 1,1-bis(4-hydroxy-3-(1-methylpropyl)phenyl)-1-phenylethane, 1,1-bis(4-hydroxy-3-cyclohexylphenyl)-1-phenylethane, 1,1-bis(4-hydroxy-3-phenylphenyl)-1-phenylethane, 1,1-bis(4-hydroxyphenyl)cyclopentane, 1,1-bis(4-hydroxyphenyl)cyclooctane, 4,4'-(1,3-phenylenediisopropylidene)bisphenol, 4,4'-(1,4-phenylenediisopropylidene)bisphenol, 9,9-bis(4-hydroxyphenyl)fluorene, 9,9-bis(4-hydroxy-3-methylphenyl)fluorene, 4,4'-dihydroxybenzophenone, 4,4'-dihydroxyphenyl ether, 4,4'-dihydroxybiphenyl, 1,1-bis(4-hydroxyphenyl)-3,3,5-trimethylcyclohexane, 1,1-bis(4-hydroxy-6-methyl-3-tert-butylphenyl)butane.

[0103] In addition, as an embodiment of other constituent units, reference may be made to the constituent 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 description in Japanese Patent Application Laid-Open No. 2011-046769, and these contents are incorporated into this specification.

[0104] In this embodiment, the lower limit of the viscosity-average molecular weight (Mv) of the recycled polycarbonate resin used is preferably 10,000 or more, more preferably 15,000 or more, and depending on the use and the like, it may be 18,000 or more, 20,000 or more, 23,000 or more, 25,000 or more. In addition, the upper limit of Mv is preferably 100,000 or less, more preferably 80,000 or less, further preferably 50,000 or less, and even more preferably 30,000 or less.

[0105] The viscosity-average molecular weight (Mv) of the polycarbonate resin is calculated by the following Schnell viscosity formula using dichloromethane as a solvent and obtaining the limiting viscosity (η) (unit: dL / g) at a temperature of 20 °C using an Ubbelohde viscometer.

[0106] η = 1.23×10 －4 Mv 0.83

[0107] In the resin composition of this embodiment, the proportion of the recycled polycarbonate resin (preferably the recycled polycarbonate resin containing the constituent unit represented by formula (1)) in the resin composition is preferably 5% by mass or more, more preferably 10% by mass or more, further preferably 30% by mass or more, even more preferably 50% by mass or more, still more preferably 70% by mass or more, still more preferably 90% by mass or more, particularly more preferably 95% by mass or more, and even more particularly preferably 99% by mass or more. The upper limit of the proportion of the recycled polycarbonate resin (preferably the recycled polycarbonate resin containing the constituent unit represented by formula (1)) in the above resin composition is preferably 100% by mass or less.

[0108] The resin composition of this embodiment may contain only one type of recycled polycarbonate resin or may contain two or more types. In the case of containing two or more types, the total amount is preferably within the above range.

[0109] The resin composition of this embodiment may further contain virgin polycarbonate resin. The virgin polycarbonate resin preferably contains the constituent unit represented by formula (1) and / or the constituent unit represented by formula (2), and more preferably a polycarbonate resin containing 90 mol% or more of the constituent unit represented by formula (1) and / or the constituent unit represented by formula (2) in total of all constituent units.

[0110] First, the polycarbonate resin containing the structural unit represented by formula (1) will be described.

[0111] Formula (1)

[0112]

[0113] (In formula (1), X 1 represents any of the following structural formulas,

[0114]

[0115] R 3 and R 4 each independently represent a hydrogen atom or a methyl group, and Z represents a group that forms an alicyclic hydrocarbon having 6 to 12 carbon atoms that may have a substituent by bonding to C.)

[0116] The detailed content of the structural unit represented by formula (1) has the same meaning as the matters described in the above-mentioned recycled polycarbonate resin, and the preferred range is also the same.

[0117] The virgin polycarbonate resin containing the structural unit represented by formula (1) preferably contains the unit represented by formula (1) in a proportion of 50 mol% or more of all the structural units, more preferably more than 50 mol%, further preferably 60 mol% or more, still more preferably 70 mol% or more, and depending on the use, etc., it can be 80 mol% or more, 90 mol% or more, 95 mol% or more, and further, it is preferably 100 mol% or less.

[0118] Next, the polycarbonate resin containing the structural unit represented by formula (2) will be described.

[0119] Formula (2)

[0120]

[0121] (In formula (2), R 1 represents a methyl group, R 2 represents a hydrogen atom or a methyl group, X 2 represents any of the following structural formulas,

[0122]

[0123] R 3 and R 4 each independently represent a hydrogen atom or a methyl group, and Z represents a group that forms an alicyclic hydrocarbon having 6 to 12 carbon atoms that may have a substituent by bonding to C.)

[0124] The two Rs in formula (2) 2 may be the same or different, and are preferably the same. R 2 is preferably a hydrogen atom.

[0125] In formula (2), X 2 is in the case of, R 3 and R 4 Preferably, at least one of them is methyl, and more preferably both are methyl.

[0126] In addition, X 2 is in the case of, Z bonds with the carbon C bonded to two phenyl groups in the above formula (2) to form a divalent alicyclic hydrocarbon group having 6 to 12 carbon atoms. As the divalent alicyclic hydrocarbon group, for example, cyclohexylidene, cycloheptylidene, cyclododecylidene, adamantylidene, cyclododecylidene and other cycloalkanediyl groups can be cited. As the substituted group, groups having a methyl substituent, an ethyl substituent, etc. thereof can be cited. Among these, cyclohexylidene, a methyl-substituted body of cyclohexylidene (preferably a 3,3,5-trimethyl-substituted body), and cyclododecylidene are preferred.

[0127] In formula (2), X 2 preferably has the following structure.

[0128]

[0129] In the present embodiment, the polycarbonate resin may contain only one kind of structural unit represented by formula (2), or may contain two or more kinds.

[0130] In the present embodiment, the polycarbonate resin may contain other structural units in addition to the structural unit represented by formula (2). As the other structural units, structural units derived from dihydroxy compounds exemplified as other structural units in addition to the structural unit represented by formula (1) described in the above recycled polycarbonate resin can be exemplified.

[0131] The virgin polycarbonate resin containing the structural unit represented by formula (2) preferably contains the unit represented by formula (2) in a proportion of 50 mol% or more of all the structural units, more preferably more than 50 mol%, further preferably 60 mol% or more, still more preferably 70 mol% or more, and depending on the use, etc., it can be 80 mol% or more, 90 mol% or more, 95 mol% or more, and in addition, it is preferably 100 mol% or less.

[0132] In this embodiment, the lower limit of the viscosity-average molecular weight (Mv) of the virgin polycarbonate resin (for example, the virgin polycarbonate resin containing the structural unit represented by formula (1) and / or the structural unit represented by formula (2)) is preferably 10,000 or more, more preferably 15,000 or more, still more preferably 18,000 or more, even more preferably 20,000 or more, and depending on the use and the like, it can be 23,000 or more, 25,000 or more, 26,000 or more. In addition, the upper limit of Mv is preferably 100,000 or less, more preferably 80,000 or less, and depending on the use and the like, it can be 50,000 or less, 30,000 or less.

[0133] In the resin composition of this embodiment, when the virgin polycarbonate resin is contained, the proportion in the resin composition is preferably 95% by mass or less, more preferably 90% by mass or less, still more preferably 70% by mass or less, even more preferably 50% by mass or less, still even more preferably 30% by mass or less. In addition, it is preferably 1% by mass or more, more preferably 5% by mass or more, still more preferably 10% by mass or more.

[0134] The resin composition of this embodiment may contain only one kind of virgin polycarbonate resin, or may contain two or more kinds. When two or more kinds are contained, the total amount is preferably within the above range.

[0135] The ratio of the viscosity-average molecular weight (Mv) of the recycled polycarbonate resin (A-1) to the viscosity-average molecular weight (Mv) of the polycarbonate resin (A-2) having the highest viscosity-average molecular weight contained in the resin composition, that is, [Mv(A-1)] / [Mv(A-2)], is 0.9 or less. By being such a ratio, there is a tendency for the flame retardancy to be further improved.

[0136] Here, the viscosity-average molecular weight of the recycled polycarbonate resin (A-1) refers to the viscosity-average molecular weight of all the recycled polycarbonate resins (mixture) contained in the resin composition (wherein, the polycarbonate resin corresponding to (A-2) is not included). On the other hand, the polycarbonate resin (A-2) having the highest viscosity-average molecular weight contained in the resin composition may be a recycled polycarbonate resin or a virgin polycarbonate resin, and refers to the polycarbonate resin having the highest viscosity-average molecular weight among the polycarbonate resins contained in the resin composition. In this embodiment, the above polycarbonate resin (A-2) having the highest viscosity-average molecular weight is preferably a virgin polycarbonate resin.

[0137] The above [Mv(A-1)] / [Mv(A-2)] is preferably 0.87 or less, more preferably 0.85 or less. In addition, it is preferably 0.35 or more.

[0138] Here, when the resin composition of the present embodiment satisfies that [Mv(A-1)] / [Mv(A-2)] is 0.9 or less, the viscosity-average molecular weight of the recycled polycarbonate resin (A-1) is preferably 10,000 or more, more preferably 12,000 or more, and further preferably less than 23,000. On the other hand, when the resin composition of the present embodiment satisfies that [Mv(A-1)] / [Mv(A-2)] is 0.9 or less, the viscosity-average molecular weight of the polycarbonate resin (A-2) is preferably 23,000 or more, more preferably 24,000 or more, may be 30,000 or more, and further preferably 80,000 or less.

[0139] In the resin composition of the present embodiment, the mass ratio of the recycled polycarbonate resin (A-1) to the polycarbonate resin (A-2) having the highest viscosity-average molecular weight contained in the above resin composition is preferably 10:90 to 90:10, more preferably 15:85 to 85:15, and further preferably 20:80 to 80:20.

[0140] <Flame retardant>

[0141] The resin composition of the present embodiment contains a flame retardant. The resin composition of the present embodiment can achieve excellent flame retardancy by containing a flame retardant together with the recycled polycarbonate resin.

[0142] The flame retardant used in the present embodiment is preferably a solid flame retardant. A solid flame retardant refers to a flame retardant that is solid (including powder and particles) at 23°C. By using a solid flame retardant, the processability during melt kneading is improved and the plasticization characteristics are suppressed, making it easier to manufacture. Examples of the solid flame retardant include potassium nonafluorobutanesulfonate, potassium diphenylsulfone sulfonate, and phenoxyphosphazene compounds.

[0143] The flame retardant used in the present embodiment preferably further contains at least one selected from halogen-based flame retardants, phosphorus-based flame retardants, metal salt-based flame retardants, and silicone-based flame retardants, more preferably contains at least one selected from phosphorus-based flame retardants and metal salt-based flame retardants, and further preferably contains a metal salt-based flame retardant. By containing a metal salt-based flame retardant, sufficient flame retardancy can be achieved even with a small amount of the compounding amount.

[0144] As the metal salt-based flame retardant, an alkali metal salt is preferred. By containing an alkali metal salt (alkali metal salt-based flame retardant), a molded article with excellent flame retardancy can be obtained. The alkali metal salt is usually an alkali metal salt of an organic acid.

[0145] Examples of the alkali metal salt include alkali metal sulfonate salts, carboxylate salts, borate salts, and phosphate salts. From the aspect of thermal stability, an alkali metal sulfonate salt is preferred.

[0146] As the metal constituting the alkali metal salt, examples include lithium (Li), sodium (Na), potassium (K), rubidium (Rb), cesium (Cs), etc. Among them, sodium, potassium, and cesium are preferred, sodium and potassium are more preferred, and potassium is further preferred.

[0147] As a preferred example of the alkali metal salt of sulfonic acid, an alkali metal salt of a fluorinated aliphatic sulfonic acid or an aromatic sulfonic acid can be cited. If specific preferred examples are given, they include alkali metal salts of fluorinated aliphatic sulfonic acids having at least 1 C-F bond (preferably having a fluoroalkyl group in the molecule) such as potassium nonafluorobutanesulfonate, lithium nonafluorobutanesulfonate, sodium nonafluorobutanesulfonate, cesium nonafluorobutanesulfonate, potassium trifluoromethanesulfonate, lithium trifluoromethanesulfonate, sodium trifluoromethanesulfonate, cesium trifluoromethanesulfonate; dipotassium diphenylsulfone disulfonate, potassium diphenylsulfone sulfonate, sodium benzenesulfonate, sodium (poly)styrenesulfonate, sodium p-toluenesulfonate, sodium (branched) dodecylbenzenesulfonate, sodium trichlorobenzenesulfonate, potassium benzenesulfonate, potassium styrenesulfonate, potassium (poly)styrenesulfonate, potassium p-toluenesulfonate, potassium (branched) dodecylbenzenesulfonate, potassium trichlorobenzenesulfonate, cesium benzenesulfonate, cesium (poly)styrenesulfonate, cesium p-toluenesulfonate, cesium (branched) dodecylbenzenesulfonate, cesium trichlorobenzenesulfonate, etc., which are alkali metal salts of aromatic sulfonic acids having at least 1 aromatic group (preferably having 2 aromatic groups in the molecule).

[0148] In addition, as the metal salt-based flame retardant, reference can be made to the descriptions in paragraphs 0069 to 0078 of Japanese Patent Laid-Open No. 2015-117298, and this content is incorporated into this specification.

[0149] As the phosphorus-based flame retardant, the phosphorus-based flame retardant used in the present invention is not particularly limited as long as it is a component containing phosphorus in the molecule that imparts flame retardancy. As a preferred phosphorus-based flame retardant, condensed phosphate ester-based flame retardants and phosphazene compounds can be cited, and phosphazene compounds are preferred.

[0150] <<Condensed Phosphate Ester-Based Flame Retardant>>

[0151] As the condensed phosphate ester-based flame retardant, a condensed phosphate ester compound represented by the formula (5) can be cited.

[0152]

[0153] The condensed phosphate ester compound represented by the above formula (5) can be a mixture of compounds having different numbers of k. In the case of a mixture of condensed phosphates with different k, k is the average value of these mixtures. k is usually an integer from 0 to 5. In the case of a mixture of compounds having different k numbers, the average k number is preferably in the range of 0.5 to 2, more preferably in the range of 0.6 to 1.5, further preferably in the range of 0.8 to 1.2, and particularly preferably in the range of 0.95 to 1.15.

[0154] In addition, X1 represents a divalent arylene group, for example, a divalent group derived from a dihydroxy compound such as resorcinol, hydroquinone, bisphenol A, 2,2'-dihydroxybiphenyl, 2,3'-dihydroxybiphenyl, 2,4'-dihydroxybiphenyl, 3,3'-dihydroxybiphenyl, 3,4'-dihydroxybiphenyl, 4,4'-dihydroxybiphenyl, 1,2-dihydroxynaphthalene, 1,3-dihydroxynaphthalene, 1,4-dihydroxynaphthalene, 1,5-dihydroxynaphthalene, 1,6-dihydroxynaphthalene, 1,7-dihydroxynaphthalene, 1,8-dihydroxynaphthalene, 2,3-dihydroxynaphthalene, 2,6-dihydroxynaphthalene, 2,7-dihydroxynaphthalene. Among these, divalent groups derived from resorcinol, bisphenol A, and 3,3'-dihydroxybiphenyl are particularly preferred.

[0155] In formula (5), p, q, r, and s each represent 0 or 1, and preferably 1.

[0156] R in formula (5) 11 , R 12 , R 13 and R 14 each represent an alkyl group having 1 to 6 carbon atoms or an aryl group having 6 to 20 carbon atoms which may be substituted by an alkyl group. Examples of such aryl groups include phenyl, tolyl, xylyl, cumylphenyl, butylphenyl, tert-butylphenyl, di-tert-butylphenyl, p-cumylphenyl, etc., and phenyl, tolyl, and xylyl are more preferred.

[0157] Specific examples of the condensed phosphate compound represented by formula (5) include aromatic phosphates such as triphenyl phosphate (TPP), tricresyl phosphate (TCP), tris(xylene) phosphate (TXP), cresyl diphenyl phosphate (CDP), 2-ethylhexyl diphenyl phosphate (EHDP), tert-butylphenyl diphenyl phosphate, bis(tert-butylphenyl)phenyl phosphate, tris(tert-butylphenyl) phosphate, cumylphenyl diphenyl phosphate, bis(cumylphenyl)diphenyl phosphate, tris(cumylphenyl) phosphate; and condensed phosphates such as resorcinol bis(diphenyl phosphate) (RDP), resorcinol bis[di(xylene)] phosphate (RDX), bisphenol A bis(diphenyl phosphate) (BDP), biphenyl bis(diphenyl phosphate), etc.

[0158] The acid value of the condensed phosphate compound represented by the formula (5) is preferably 0.2 mgKOH / g or less, more preferably 0.15 mgKOH / g or less, still more preferably 0.1 mgKOH or less, and particularly preferably 0.05 mgKOH / g or less. The lower limit of the above acid value can also be substantially 0. In addition, the content of the half ester of the condensed phosphate compound represented by the formula (5) is preferably 1% by mass or less, more preferably 0.5% by mass or less. By making the acid value 0.2 mgKOH / g or less and the half ester content 1% by mass or less, there is a tendency that the thermal stability and hydrolysis resistance of the resin composition of the present embodiment are further improved.

[0159] As the phosphate compound, in addition to the above phosphate compound, it also includes a polyester resin, a polycarbonate resin or an epoxy resin containing a phosphate moiety.

[0160] <<Phosphazene compound>>

[0161] As the phosphorus-based flame retardant, a phosphazene compound is also preferred. By containing a phosphazene compound, there is a tendency that the heat resistance of the obtained molded product is more excellent.

[0162] The phosphazene compound that can be used in the present embodiment is an organic compound having a -P=N- bond in the molecule. As the phosphazene compound, a cyclic phosphazene compound represented by the formula (6A), a linear phosphazene compound represented by the formula (6B), and a crosslinked phosphazene compound in which at least one phosphazene compound selected from the formula (6A) and the formula (6B) is crosslinked by a crosslinking group can be preferably selected. As the crosslinked phosphazene compound, from the viewpoint of flame retardancy, a crosslinked phosphazene compound crosslinked by a crosslinking group represented by the following formula (6C) is preferred.

[0163]

[0164] (In the formula (6A), a is an integer of 3 to 25, and R 5 may be the same or different and represents an aryl group or an alkylaryl group.)

[0165]

[0166] (In the formula (6B), b is an integer of 3 to 10000, Z represents a -N=P(OR 5 )3 group or a -N=P(O)OR 5 group, Y represents a -P(OR 5 )4 group or a P(O)(OR 5 )2 group. R 5 may be the same or different and represents an aryl group or an alkylaryl group.)

[0167]

[0168] (In formula (6C), A is -C(CH3)2-, -SO2-, -S- or -O-, and l is 0 or 1.)

[0169] As the cyclic and / or chain-like phenoxyphosphazene compounds represented by formulae (6A) and (6B), for example, phenoxyphosphazene, (poly)toluenoxyphosphazene (e.g., o-toluenoxyphosphazene, m-toluenoxyphosphazene, p-toluenoxyphosphazene, o,m-toluenoxyphosphazene, o,p-toluenoxyphosphazene, m,p-toluenoxyphosphazene, o,m,p-toluenoxyphosphazene, etc.), (poly)xylenoxyphosphazene and other cyclic and / or chain-like C1-6 alkyl C6-20 aryloxyphosphazene, (poly)phenoxytoluenoxyphosphazene (e.g., phenoxyo-toluenoxyphosphazene, phenoxym-toluenoxyphosphazene, phenoxyp-toluenoxyphosphazene, phenoxyo,m-toluenoxyphosphazene, phenoxyo,p-toluenoxyphosphazene, phenoxym,p-toluenoxyphosphazene, phenoxyo,m,p-toluenoxyphosphazene, etc.), (poly)phenoxyxylenoxyphosphazene, (poly)phenoxytoluenoxyxylenoxyphosphazene and other cyclic and / or chain-like C6-20 aryl C1-10 alkyl C6-20 aryloxyphosphazene, etc. are exemplified. Preferably, they are cyclic and / or chain-like phenoxyphosphazene, cyclic and / or chain-like C1-3 alkyl C6-20 aryloxyphosphazene, C6-20 aryloxy C1-3 alkyl C6-20 aryloxyphosphazene (e.g., cyclic and / or chain-like toluenoxyphosphazene, cyclic and / or chain-like phenoxytolylphenoxyphosphazene, etc.). It should be noted that here, the description of "C1-6" means "1 to 6 carbon atoms", and the same applies to "C6-20", "C1-10", etc. In addition, the description of "(poly)phenoxy···" means one or both of "phenoxy···" and "polyphenoxy···".

[0170] As the cyclic phosphazene compound represented by formula (6A), a cyclic phenoxyphosphazene with R 5 being phenyl is particularly preferred. As such cyclic phenoxyphosphazene compounds, for example, compounds such as phenoxycyclotriphosphazene, octaphenoxycyclotetraphosphazene, and decaphenoxycyclopentaphosphazene obtained by substituting phenoxy for cyclic chlorophosphazene such as hexachlorocyclotriphosphazene, octachlorocyclotetraphosphazene, and decachlorocyclopentaphosphazene extracted from the cyclic and linear chlorophosphazene mixture obtained by reacting ammonium chloride with phosphorus pentachloride at a temperature of 120 to 130 °C can be cited. In addition, the cyclic phenoxyphosphazene compound is preferably a compound in which a in formula (6A) is an integer of 3 to 8, and it can also be a mixture of compounds with different a values. Among them, a mixture of compounds in which the compound with a = 3 is 50% by mass or more, the compound with a = 4 is 10 to 40% by mass, and the total of compounds with a = 5 or more is 30% by mass or less is preferred.

[0171] As the chain-like phosphazene compound represented by formula (6B), R 5A chain-like phenoxyphosphazene in which R is phenyl. As such a chain-like phenoxyphosphazene compound, for example, a compound obtained by subjecting hexachlorocyclotriphosphazene obtained by the above method to ring-opening polymerization at a temperature of 220 to 250°C and substituting the resulting linear dichlorophosphazene having a degree of polymerization of 3 to 10,000 with phenoxy groups can be mentioned. In the formula (6B) of the linear phenoxyphosphazene compound, b is preferably 3 to 1,000, more preferably 3 to 100, and still more preferably 3 to 25.

[0172] As the crosslinked phenoxyphosphazene compound, for example, a compound having a crosslinked structure of 4,4'-sulfonyldiphenylene (bisphenol S residue), a compound having a crosslinked structure of 2,2-(4,4'-diphenylene) isopropylidene, a compound having a crosslinked structure of 4,4'-oxydiphenylene, a compound having a crosslinked structure of 4,4'-thiodiphenylene, and other compounds having a crosslinked structure of 4,4'-diphenylene can be mentioned.

[0173] In addition, as the crosslinked phosphazene compound, from the viewpoint of flame retardancy, in the above formula (6A), R 5 A crosslinked phenoxyphosphazene compound formed by crosslinking a cyclic phenoxyphosphazene compound in which R is phenyl with a crosslinking group represented by the above formula (6C) or a crosslinked phenoxyphosphazene compound formed by crosslinking a chain-like phenoxyphosphazene compound in which R is phenyl in the above formula (6B) with a crosslinking group represented by the above formula (6C), and more preferably a crosslinked phenoxyphosphazene compound formed by crosslinking a cyclic phenoxyphosphazene compound with a crosslinking group represented by the above formula (6C). 5 A crosslinked phenoxyphosphazene compound formed by crosslinking a cyclic phenoxyphosphazene compound in which R is phenyl with a crosslinking group represented by the above formula (6C) or a crosslinked phenoxyphosphazene compound formed by crosslinking a chain-like phenoxyphosphazene compound in which R is phenyl in the above formula (6B) with a crosslinking group represented by the above formula (6C), and more preferably a crosslinked phenoxyphosphazene compound formed by crosslinking a cyclic phenoxyphosphazene compound with a crosslinking group represented by the above formula (6C).

[0174] In addition, the content of phenylene in the crosslinked phenoxyphosphazene compound is usually 50 to 99.9%, preferably 70 to 90%, based on all the phenyl and phenylene groups in the cyclic phosphazene compound represented by the formula (6A) and / or the chain-like phenoxyphosphazene compound represented by the formula (6B). In addition, the above crosslinked phenoxyphosphazene compound is particularly preferably a compound having no free hydroxyl group in its molecule.

[0175] In the present invention, from the viewpoints of flame retardancy and mechanical properties, the phosphazene compound is preferably at least one selected from the cyclic phenoxyphosphazene compound represented by the above formula (6A) and the crosslinked phenoxyphosphazene compound formed by crosslinking the cyclic phenoxyphosphazene compound represented by the above formula (6A) with a crosslinking group.

[0176] As commercially available products of such phosphazene compounds, for example, "Rabitle FP-110T", "Rabitle FP-100T" manufactured by Fushimi Pharmaceutical Co., Ltd. and "SPS100" manufactured by Otsuka Chemical Co., Ltd. as phenoxyphosphazene can be mentioned.

[0177] In addition to the above phosphazene compounds, as the phosphorus-based flame retardant, reference can be made to the descriptions in paragraphs 0044 to 0056 of Japanese Patent Application Laid-Open No. 2022-80749, and the content is incorporated into this specification.

[0178] The content of the flame retardant (preferably a metal salt-based flame retardant, more preferably an alkali metal salt of sulfonic acid) in the resin composition of this embodiment is preferably 0.005 parts by mass or more, more preferably 0.008 parts by mass or more, further preferably 0.01 parts by mass or more, still more preferably 0.03 parts by mass or more, and even more preferably 0.05 parts by mass or more with respect to 100 parts by mass of the polycarbonate resin (the total of virgin polycarbonate resin and recycled polycarbonate resin). By being at the above lower limit value or more, the formation of the carbonized layer during the combustion of the polycarbonate resin can be promoted, and the flame retardancy can be further improved. In addition, the content of the above flame retardant is preferably 30 parts by mass or less, more preferably 25 parts by mass or less, further preferably less than 25 parts by mass, still more preferably 20 parts by mass or less, even more preferably 15 parts by mass or less, and in addition, preferably 10 parts by mass or less, 5 parts by mass or less, 3 parts by mass or less, 1 part by mass or less, 0.8 part by mass or less, 0.5 part by mass or less, 0.3 part by mass or less, 0.2 part by mass or less, and 0.15 part by mass or less in sequence with respect to 100 parts by mass of the polycarbonate resin. By being at the above upper limit value or less, there is a tendency that the flame retardant effect can be more effectively exerted even though the content of the flame retardant is reduced.

[0179] The resin composition of this embodiment may contain only one kind of flame retardant, or may contain two or more kinds. When containing two or more kinds, the total content is preferably in the above range.

[0180] When the resin composition of this embodiment contains a metal salt-based flame retardant, its content is preferably 0.005 parts by mass or more, more preferably 0.008 parts by mass or more, further preferably 0.01 parts by mass or more, still more preferably 0.03 parts by mass or more, and even more preferably 0.05 parts by mass or more with respect to 100 parts by mass of the polycarbonate resin (the total of virgin polycarbonate resin and recycled polycarbonate resin). By being at the above lower limit value or more, the formation of the carbonized layer during the combustion of the polycarbonate resin can be promoted, and the flame retardancy can be further improved. In addition, the content of the above flame retardant is preferably 1 part by mass or less, more preferably 0.8 part by mass or less, further preferably 0.5 part by mass or less, still more preferably 0.3 part by mass or less, even more preferably 0.2 part by mass or less, and even more preferably 0.15 part by mass or less with respect to 100 parts by mass of the polycarbonate resin. By being at the above upper limit value or less, there is a tendency that the flame retardant effect can be more effectively exerted even though the content of the flame retardant is reduced.

[0181] When the resin composition of the present embodiment contains a phosphorus-based flame retardant, its content is preferably 1 part by mass or more, more preferably 3 parts by mass or more, still more preferably 5 parts by mass or more, and even more preferably 10 parts by mass or more with respect to 100 parts by mass of the polycarbonate resin (the total of the virgin polycarbonate resin and the recycled polycarbonate resin). By being at least the above lower limit value, the formation of a carbonized layer during the combustion of the polycarbonate resin can be promoted, and the flame retardancy can be further improved. In addition, the content of the above flame retardant is preferably 30 parts by mass or less, more preferably 25 parts by mass or less, still more preferably 20 parts by mass or less, and even more preferably 15 parts by mass or less with respect to 100 parts by mass of the polycarbonate resin.

[0182] An example of the resin composition of the present embodiment substantially does not contain a flame retardant other than the metal salt-based flame retardant. Substantially not containing means that the content of the flame retardant other than the metal salt-based flame retardant in the flame retardants contained in the resin composition is 10% by mass or less, preferably 5% by mass or less, more preferably 3% by mass or less, and still more preferably 1% by mass or less of the content of the flame retardant other than the metal salt-based flame retardant.

[0183] The resin composition of the present embodiment substantially does not contain a fluoropolymer. Substantially not containing means that the content of the fluoropolymer in the resin composition is 0 part by mass or more and less than 0.01 part by mass, preferably 0 part by mass or more and less than 0.001 part by mass with respect to 100 parts by mass of the above polycarbonate resin. Even if the resin composition of the present embodiment has a composition that does not substantially contain a fluoropolymer such as an anti-dripping agent, excellent flame retardancy can be achieved, and thus a resin composition or a molded article having excellent transparency can be obtained.

[0184] <Ultraviolet Absorbent>

[0185] The resin composition of the present embodiment may contain an ultraviolet absorbent.

[0186] As the ultraviolet absorbent, benzotriazole-based ultraviolet absorbents, benz oxazine-based ultraviolet absorbents, triazine-based ultraviolet absorbents, and malonic ester-based ultraviolet absorbents are preferably exemplified, and benzotriazole-based ultraviolet absorbents are preferred.

[0187] As benzotriazole-based ultraviolet absorbers, for example, 2-(2-hydroxy-5-methylphenyl)-2H-benzotriazole, 2-(2-hydroxy-3,5-di-tert-butylphenyl)-2H-benzotriazole, 2-(2-hydroxy-3-tert-butyl-5-methylphenyl)-2H-benzotriazole, 2-(2-hydroxy-5-tert-octylphenyl)-2H-benzotriazole, 2-(3,5-di-tert-octyl-2-hydroxyphenyl)-2H-benzotriazole, 2-(3,5-di-tert-amyl-2-hydroxyphenyl)-2H-benzotriazole, 2-(3-lauryl-5-methyl-2-hydroxyphenyl)-2H-benzotriazole, 2-(3,5-di-tert-butyl-2-hydroxyphenyl)-5-chloro-2H-benzotriazole, 2-(3-tert-butyl-5-methyl-2-hydroxyphenyl)-5-chloro-2H-benzotriazole, 2-(3,5-bis(1-methyl-1-phenylethyl)-2-hydroxyphenyl)-2H-benzotriazole, bis(3-(2H-benzotriazol-2-yl)-2-hydroxy-5-methylphenyl)methane, bis(3-(2H-benzotriazol-2-yl)-2-hydroxy-5-(1,1,3,3-tetramethylbutyl)phenyl)methane, bis(3-(2H-benzotriazol-2-yl)-2-hydroxy-5-cumylphenyl)methane, bis(3-(2H-benzotriazol-2-yl)-2-hydroxy-5-octylphenyl)methane, 1,1-bis(3-(2H-benzotriazol-2-yl)-2-hydroxy-5-methylphenyl)octane, 1,1-bis(3-(2H-5-chlorobenzotriazol-2-yl)-2-hydroxy-5-methylphenyl)octane, 1,2-ethanediyl bis(3-(2H-benzotriazol-2-yl)-2-hydroxybenzoate), 1,12-dodecanediyl bis(3-(2H-benzotriazol-2-yl)-4-hydroxybenzoate), 1,3-cyclohexanediyl bis(3-(5-chloro-2H-benzotriazol-2-yl)-2-hydroxybenzoate), 1,4-butanediyl bis(3-(2H-benzotriazol-2-yl)-4-hydroxy-5-methylphenylacetate), 3,6-dioxa-1,8-octanediyl bis(3-(5-methoxy-2H-benzotriazol-2-yl)-4-hydroxyphenylacetate), 1,6-Hexanediyl bis(3-(3-(2H-benzotriazol-2-yl)-4-hydroxy-5-tert-butylphenyl)propionate), p-Xylylene bis(3-(3-(2H-benzotriazol-2-yl)-4-hydroxyphenyl)propionate), bis(3-(2H-benzotriazol-2-yl)-4-hydroxytolyl)malonate, bis(2-(3-(2H-benzotriazol-2-yl)-4-hydroxy-5-octylphenyl)ethyl)terephthalate, bis(3-(2H-benzotriazol-2-yl)-4-hydroxy-5-propyltolyl)suberate, 2-(2H-benzotriazol-2-yl)-6-phthalimidomethyl-4-methylphenol, 2-(2H-benzotriazol-2-yl)-6-phthalimidoethyl-4-methylphenol, 2-(2H-benzotriazol-2-yl)-6-phthalimidooctyl-4-methylphenol, 2-(2H-benzotriazol-2-yl)-6-phthalimidomethyl-4-tert-butylphenol, 2-(2H-benzotriazol-2-yl)-6-phthalimidomethyl-4-cumylphenol, 2-(2H-benzotriazol-2-yl)-4,6-bis(phthalimidomethyl)phenol, etc. Among these, 2-(2-hydroxy-5-tert-octylphenyl)-2H-benzotriazole is preferred.,

[0188] As the ultraviolet absorber, reference can be made to the descriptions in paragraphs 0059 to 0062 of Japanese Patent Application Laid-Open No. 2016-216534 and paragraphs 0069 to 0082 of Japanese Patent Application Laid-Open No. 2018-178019, and these contents are incorporated herein in this specification.,

[0189] In the resin composition of this embodiment, when an ultraviolet absorber is contained, the content of the above ultraviolet absorber is preferably 0.01 part by mass or more, more preferably 1 part by mass or less, still more preferably 0.03 to 0.7 part by mass, and further preferably 0.05 to 0.5 part by mass with respect to 100 parts by mass of the polycarbonate resin (the total of virgin polycarbonate resin and recycled polycarbonate resin).

[0190] The ultraviolet absorber may be contained in the resin composition of this embodiment by only one kind, or may contain two or more kinds. When two or more kinds are contained, the total amount is preferably in the above range.,

[0191] <Stabilizer>

[0192] The resin composition of this embodiment may contain a stabilizer.,

[0193] Examples of the stabilizer include heat stabilizers and antioxidants.,

[0194] As the heat stabilizer, a phosphorus-based stabilizer is preferably used.,

[0195] As the phosphorus-based stabilizer, any known phosphorus-based stabilizer can be used. If specific examples are given, oxygen-containing acids of phosphorus such as phosphoric acid, phosphonic acid, phosphorous acid, hypophosphorous acid, polyphosphoric acid, etc. can be cited; acid pyrophosphate metal salts such as acidic sodium pyrophosphate, acidic potassium pyrophosphate, acidic calcium pyrophosphate, etc.; phosphates of Group IA or Group IIB metals such as potassium phosphate, sodium phosphate, cesium phosphate, zinc phosphate, etc.; organic phosphate ester compounds, organic phosphite ester compounds, organic phosphonate ester compounds, etc., and organic phosphite ester compounds are particularly preferred.

[0196] As the antioxidant, a hindered phenol-based stabilizer is preferably used.

[0197] Specific examples of the hindered phenol-based stabilizer include pentaerythritol tetra[3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate], octadecyl 3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate, thiodiethylene bis[3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate], N,N'-hexane-1,6-diylbis[3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionamide], 2,4-dimethyl-6-(1-methylpentadecyl)phenol, diethyl [[3,5-bis(1,1-dimethylethyl)-4-hydroxyphenyl]methyl]phosphate, 3,3',3",5,5',5"-hexatert-butyl-a,a',a"-(mesitylene-2,4,6-triyl)tris-p-cresol, 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-triazin-2-ylamino)phenol, 2-[1-(2-hydroxy-3,5-di-tert-amylphenyl)ethyl]-4,6-di-tert-amylphenyl acrylate, etc.

[0198] As such hindered phenol-based stabilizers, specifically, for example, "Irganox (registered trademark. The same applies hereinafter) 1010" and "Irganox1076" manufactured by BASF, "ADK STAB AO-50" and "ADK STAB AO-60" manufactured by ADEKA, etc. can be cited.

[0199] The content of the stabilizer in the resin composition of the present embodiment is usually 0.001 parts by mass or more, preferably 0.005 parts by mass or more, more preferably 0.01 parts by mass or more, relative to 100 parts by mass of the polycarbonate resin (the total of the virgin polycarbonate resin and the recycled polycarbonate resin). In addition, it is usually 1 part by mass or less, preferably 0.5 parts by mass or less, more preferably 0.3 parts by mass or less. By making the content of the stabilizer within the above range, the addition effect of the stabilizer can be more effectively exerted.

[0200] The resin composition of the present embodiment may contain only one kind of stabilizer, or may contain two or more kinds. When two or more kinds are contained, the total amount is preferably within the above range.

[0201] <Release agent>

[0202] The resin composition of the present embodiment may contain a release agent.

[0203] Examples of the release agent include aliphatic carboxylic acids, salts of aliphatic carboxylic acids, esters of aliphatic carboxylic acids and alcohols, aliphatic hydrocarbon compounds having a number average molecular weight of 200 to 15,000, polysiloxane-based silicone oils, ketone waxes, light amides, etc. Aliphatic carboxylic acids, salts of aliphatic carboxylic acids, and esters of aliphatic carboxylic acids and alcohols are preferred.

[0204] For the detailed content of the release agent, reference can be made to the descriptions in paragraphs 0055 to 0061 of Japanese Patent Laid-Open No. 2018-095706, and these contents are incorporated into this specification.

[0205] When the resin composition of the present embodiment contains a release agent, its content in the resin composition is preferably 0.05 to 3% by mass, more preferably 0.1 to 0.8% by mass, and further preferably 0.1 to 0.6% by mass.

[0206] The resin composition of the present embodiment may contain only one kind of release agent, or may contain two or more kinds. When two or more kinds are contained, the total amount is preferably within the above range.

[0207] <Other components>

[0208] The resin composition of the present embodiment may contain a polycarbonate resin, a metal salt-based flame retardant, and the above additives. In addition, as long as the desired physical properties are not significantly hindered, other components other than the above may be contained as needed. Examples of other components include other thermoplastic resins, various resin additives, resin reinforcing materials (glass fibers, glass fillers), etc.

[0209] As resin additives, for example, antistatic agents, colorants, antifogging agents, lubricants, antiblocking agents, fluidity improvers, plasticizers, dispersants, antibacterial agents, etc. can be cited. It should be noted that the resin additives may contain one kind, or may contain two or more kinds in any combination and ratio. For their detailed information, reference can be made to the descriptions in paragraphs 0059 to 0080 of Japanese Patent Application Laid-Open No. 2014-065901 and paragraphs 0069 to 0093 of Japanese Patent Application Laid-Open No. 2018-165017, and the content thereof is incorporated into this specification.

[0210] The resin composition of the present embodiment is adjusted so that the total of the polycarbonate resin, the flame retardant, and the resin additives (for example, ultraviolet absorbers, stabilizers, mold release agents) blended as required is 100% by mass.

[0211] <Physical properties of the resin composition>

[0212] The resin composition of the present embodiment has a small haze. Specifically, when the resin composition of the present embodiment is molded into a thickness of 1 mm, the haze is preferably 5.0% or less, more preferably 4.0% or less, still more preferably 3.5% or less, and even more preferably 3.0% or less. The lower limit value of the above haze is actually greater than 0%, and even if it is 0.01% or more, it fully satisfies the required performance.

[0213] The above haze is measured according to the description of the examples described later.

[0214] The resin composition of the present embodiment preferably has excellent flame retardancy.

[0215] Specifically, when the resin composition of the present embodiment is molded into a thickness of 1.5 mm, the total burning time is preferably 35 seconds or less, more preferably 30 seconds or less, still more preferably 29 seconds or less, even more preferably 27 seconds or less, still even more preferably 26 seconds or less, and further even more preferably 25 seconds or less. In addition, the lower limit of the above total burning time is, for example, actually 10 seconds or more.

[0216] In addition, when the resin composition of the present embodiment is molded into a thickness of 1.5 mm, it is more preferably dripped 3 times or less, further preferably dripped 2 times or less, even more preferably dripped 1 time or less, and further preferably has no dripping.

[0217] The flame retardancy is measured according to the description of the examples described later.

[0218] <Manufacturing method of the resin composition>

[0219] The manufacturing method of the resin composition of the present embodiment can widely adopt the well-known manufacturing methods of polycarbonate resin compositions without limitation. Examples of such methods include: pre-mixing a polycarbonate resin, a flame retardant, and other components as required using various mixers such as a drum, a Henschel mixer, etc., and then performing melt-kneading using mixers such as a Banbury mixer, a roll, a Brabender, a single-screw kneading extruder, a twin-screw kneading extruder, a kneader, etc.

[0220] It should be noted that the temperature of the melt-kneading is not particularly limited and is usually in the range of 240 to 320°C.

[0221] <Molded article>

[0222] One form of the resin composition of the present embodiment is pellets.

[0223] In addition, the above resin composition (for example, pellets) can be formed into a molded article by various molding methods. That is, the molded article of the present embodiment is formed from the resin composition or pellets of the present embodiment.

[0224] The shape of the molded article is not particularly limited and can be appropriately selected according to the use and purpose of the molded article. For example, examples include a film shape, a rod shape, a cylindrical shape, a ring shape, a circular shape, an elliptical shape, a polygonal shape, a special-shaped article, a hollow article, a frame shape, a box shape, a panel shape, etc. Among them, a panel shape is preferred, and the thickness is, for example, about 1 mm to 5 mm.

[0225] As the method of molding into a molded article, there is no particular limitation, and conventional well-known molding methods can be adopted. For example, examples include an injection molding method, an injection compression molding method, an extrusion molding method, a special-shaped extrusion method, a transfer molding method, a hollow molding method, a gas-assisted hollow molding method, a blow molding method, an extrusion blow molding method, an IMC (in-mold coating molding) method, a rotational molding method, a multi-layer molding method, a two-color molding method, an insert molding method, a sandwich molding method, a foam molding method, a compression molding method, etc. In particular, the resin composition of the present embodiment is suitable for molded articles obtained by an injection molding method, an injection compression molding method, and an extrusion molding method. However, the resin composition of the present embodiment is of course not limited to molded articles obtained by these methods.

[0226] The molded article of the present embodiment is widely used in applications that require flame retardancy. Specifically, it can be suitably used for components such as electrical and electronic devices, OA equipment, portable information terminal devices, mechanical parts, vehicle-related parts, building parts, various containers, leisure goods and miscellaneous goods, lighting equipment, battery peripheral products, etc. As vehicle-related parts, specifically, components of electric vehicles, components of electric bicycles, components of charging guns, components of charging stations, etc. can be exemplified. Among these, components for displays, portable information terminal components, household electrical products, in-vehicle related components, battery peripheral products, or interior furnishings are particularly preferred.

[0227] Examples

[0228] Hereinafter, examples are given to illustrate the present invention more specifically. The materials, amounts used, ratios, treatment contents, treatment steps, etc. shown in the following examples can be appropriately changed as long as they do not deviate from the gist of the present invention. Therefore, the scope of the present invention is not limited to the specific examples shown below.

[0229] When it is difficult to obtain the measuring instruments, etc. used in the examples due to production suspension, etc., other instruments with equivalent performance can be used for measurement.

[0230] 1. Raw materials

[0231] The raw materials described in Tables 1 and 2 below are used.

[0232] [Table 1]

[0233]

[0234] [Table 2]

[0235]

[0236] The above flame retardants B1 to B3 are all solids at 23°C.

[0237] 2. Examples 1 to 9, Comparative Examples 1 to 7

[0238] <Manufacture of resin composition pellets>

[0239] The respective components described in Table 1 or Table 2 above are mixed in the ratios shown in Tables 3 to 7 (expressed in parts by mass unless otherwise specified), uniformly mixed using a drum mixer, and then supplied from an upstream feeder to a twin-screw extruder (manufactured by Shibaura Machine Co., Ltd., TEM26SX) having 1 exhaust port. The material is fed into the extruder from the barrel at the upstream part of the extruder at a barrel set temperature of 260°C, a screw rotation speed of 180 rpm, and a discharge rate of 25 kg / hr, and melt-kneaded to obtain resin composition pellets.

[0240] <Haze>

[0241] The haze is measured at 23°C for the 1-mm thick part of the three-piece test piece in accordance with JIS K-7105.

[0242] Specifically, after drying the resin composition pellets obtained above at 120°C for 5 hours, an injection molding machine ("J55-60H" manufactured by Japan Steel Works, Ltd.) is used to injection mold into a three-piece test piece (60 mm × 30 mm × 1 mm thick + 60 mm × 30 mm × 2 mm thick + 60 mm × 30 mm × 3 mm thick) under the conditions of a barrel set temperature of 280°C, a mold temperature of 80°C, a screw rotation speed of 100 rpm, and an injection speed of 100 mm / s. However, in Examples 7 and 8 and Comparative Examples 6 and 7, after drying at a drying temperature of 100°C for 5 hours, they are injection molded into a three-piece test piece by the same method.

[0243] The HAZE (haze) at 23°C of the flat test piece obtained above is measured using a haze meter in accordance with JIS K-7105.

[0244] The haze meter used is the SH-7000 type haze meter manufactured by Nippon Denshoku Industries Co., Ltd.

[0245] The unit of haze is expressed in %.

[0246] <Flammability>

[0247] <<Manufacture of Test Piece>>

[0248] After drying the resin composition pellets obtained above at 120°C for 5 hours, an injection molding machine ("SE100EV" of Sumitomo Heavy Industries, Ltd.) is used to injection mold into a long strip-shaped test piece for combustion test (125 mm × 13 mm × 1.5 mm thick) under the conditions of a barrel set temperature of 260°C, a mold temperature of 80°C, a screw rotation speed of 100 rpm, and an injection speed of 15 mm / s. However, in Examples 7 and 8 and Comparative Examples 6 and 7, after drying at a drying temperature of 100°C for 5 hours, they are injection molded into a three-piece test piece by the same method.

[0249] <<Combustion Test>>

[0250] For the obtained test piece for combustion test, a vertical combustion test is carried out using 5 test pieces in accordance with the method of Underwriters Laboratories' Subject 94 (UL94). The total combustion time is expressed in seconds.

[0251] <<Comprehensive Evaluation>>

[0252] The evaluation is carried out as follows.

[0253] 1: No dripping, total burning time is 35 seconds or less

[0254] 2: No dripping, total burning time exceeds 35 seconds

[0255] 3: Dripping times are 1 - 2 times

[0256] 4: Dripping times are more than 3 times

[0257] [Table 3]

[0258]

[0259] [Table 4]

[0260]

[0261] [Table 5]

[0262]

[0263] [Table 6]

[0264]

[0265] [Table 7]

[0266]

[0267] In the above table, Mv(A - 1) represents the viscosity - average molecular weight (Mv) of the recycled polycarbonate resin (A - 1), and Mv(A - 2) represents the viscosity - average molecular weight (Mv) of the polycarbonate resin (A - 2) with the highest viscosity - average molecular weight contained in the resin composition. In addition, MvA / MvB represents the value of Mv of recycled polycarbonate (PCR - PC) / Mv of virgin polycarbonate.

[0268] In Examples 1 - 9, when 26 parts by mass of the flame retardant (D) was compounded relative to 100 parts by mass of the polycarbonate resin and carried out in the same manner otherwise, extrusion molding could not be performed in any of the examples, and pellets could not be obtained.

[0269] Based on the above results, it is shown that the molded article formed from the resin composition of the present invention has excellent flame retardancy, especially excellent dripping inhibition property. In particular, when a fluoropolymer (dripping inhibitor) having fibril - forming ability is compounded in the polycarbonate resin to achieve flame retardancy, the transparency is poor, but the resin composition of the present invention can achieve flame retardancy without compounding a fluoropolymer and obtain a resin composition with excellent transparency.

Claims

1. A resin composition comprising a polycarbonate resin and a flame retardant, wherein the polycarbonate resin comprises a recycled polycarbonate resin, the resin composition substantially does not contain a fluoropolymer, the ratio of the viscosity-average molecular weight Mv of the recycled polycarbonate resin (A-1) to the viscosity-average molecular weight Mv of the polycarbonate resin (A-2) having the highest viscosity-average molecular weight contained in the resin composition, i.e., [Mv(A-1)] / [Mv(A-2)], is 0.9 or less.

2. A resin composition comprising a polycarbonate resin and a flame retardant, wherein the polycarbonate resin comprises a recycled polycarbonate resin, the resin composition substantially does not contain a fluoropolymer, the content of the flame retardant is less than 25 parts by mass relative to 100 parts by mass of the polycarbonate resin.

3. The resin composition according to claim 1 or 2, wherein, The flame retardant comprises a metal salt-based flame retardant.

4. The resin composition according to claim 1 or 2, wherein, The flame retardant comprises an alkali metal salt of sulfonic acid.

5. The resin composition according to claim 1 or 2, wherein, The flame retardant comprises a phosphorus-based flame retardant.

6. The resin composition according to claim 1 or 2, wherein, The flame retardant comprises a phosphazene compound.

7. The resin composition according to claim 1 or 2, wherein The flame retardant is a solid flame retardant.

8. The resin composition according to claim 1 or 2, wherein The recycled polycarbonate resin comprises a structural unit represented by formula (1), Formula (1) In formula (1), X 1 represents any of the following structural formulas, R 3 and R 4 each independently represents a hydrogen atom or a methyl group, and Z represents a group which forms an alicyclic hydrocarbon having 6 to 12 carbon atoms and which may have a substituent by bonding to C.

9. The resin composition according to claim 1 or 2, wherein further contains a virgin polycarbonate resin, the virgin polycarbonate resin comprises a structural unit represented by formula (1), Formula (1) In formula (1), X 1 represents any of the following structural formulas, R 3 and R 4 each independently represents a hydrogen atom or a methyl group, and Z represents a group that forms an alicyclic hydrocarbon having 6 to 12 carbon atoms which may have substituents by bonding to C.

10. The resin composition according to claim 1 or 2, wherein further contains a virgin polycarbonate resin, the virgin polycarbonate resin comprises a structural unit represented by formula (2), Formula (2) In formula (2), R 1 represents a methyl group, R 2 represents a hydrogen atom or a methyl group, and X 1 represents any one of the following structural formulas: R 3 and R 4 each independently represents a hydrogen atom or a methyl group, and Z represents a group which forms an alicyclic hydrocarbon having 6 to 12 carbon atoms and which may have substituents by bonding to C.

11. The resin composition according to claim 1 or 2, wherein, the content of the polycarbonate resin in the resin composition is 10 to 95% by mass, the content of the flame retardant is 0.005 parts by mass or more relative to 100 parts by mass of the polycarbonate resin.

12. The resin composition according to claim 1 or 2, wherein The mass ratio of the recycled polycarbonate resin (A-1) to the polycarbonate resin (A-2) having the highest viscosity-average molecular weight contained in the resin composition is 10:90 to 90:

10.

13. The resin composition according to claim 1 or 2, wherein, The flame retardant comprises an alkali metal salt of sulfonic acid and / or a phosphazene compound, the flame retardant is a solid flame retardant, the recycled polycarbonate resin comprises a structural unit represented by formula (1), the resin composition further contains a virgin polycarbonate resin, the virgin polycarbonate resin comprises a structural unit represented by formula (1) and / or a structural unit represented by formula (2), the content of the polycarbonate resin in the resin composition is 10 to 95% by mass, the content of the flame retardant is 0.005 parts by mass or more relative to 100 parts by mass of the polycarbonate resin, the mass ratio of the recycled polycarbonate resin (A-1) to the polycarbonate resin (A-2) having the highest viscosity-average molecular weight contained in the resin composition is 10:90 to 90:10, Formula (1) In formula (1), X 1 represents any of the following structural formulas, R 3 and R 4 each independently represents a hydrogen atom or a methyl group, and Z represents a group that forms an alicyclic hydrocarbon having 6 to 12 carbon atoms which may have substituents by bonding to C Formula (2) In formula (2), R 1 represents methyl, R 2 represents a hydrogen atom or methyl, and X 1 represents any one of the following structural formulas: R 3 and R 4 each independently represents a hydrogen atom or a methyl group, and Z represents a group which forms an alicyclic hydrocarbon having 6 to 12 carbon atoms and which may have substituents by bonding to C.

14. Pellets of the resin composition according to claim 1 or 2.

15. A molded article obtained by molding the resin composition according to claim 1 or 2.

16. A molded article obtained by molding the pellets according to claim 14.

17. A method for manufacturing a resin composition, the resin composition substantially does not contain a fluoropolymer, the manufacturing method comprising the following steps: melt-kneading a recycled polycarbonate resin (A-1), a polycarbonate resin (A-2) and a flame retardant, The ratio of the viscosity-average molecular weight Mv of the recycled polycarbonate resin (A-1) to the viscosity-average molecular weight Mv of the polycarbonate resin (A-2), that is, [Mv(A-1)] / [Mv(A-2)], is 0.9 or less.

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