Resin composition, pellet, and molded article

Abstract

Provided are a resin composition capable of providing a molded article having a low YI value, a pellet, and a molded article. This resin composition contains 0.01-1.5 parts by mass of a compound represented by formula (1) with respect to 100 parts by mass of a polycarbonate resin. In formula (1), R each independently represent a substituted or unsubstituted C1-10 aliphatic hydrocarbon group.

Description

Resin composition, pellets, and molded products

[0001] The present invention relates to a resin composition, a pellet, and a molded article, and more particularly to a resin composition containing a polycarbonate resin as a main component.

[0002] Polycarbonate resins have traditionally been widely used in a variety of applications due to their excellent performance. In particular, one application of polycarbonate resins is their active use in components requiring transparency, such as power covers, lighting lenses, lighting covers, and light-guiding components. For example, Patent Document 1 discloses polycarbonate resin composition pellets containing a polycarbonate resin (A), an aromatic compound (B) represented by the following formula, and a phosphorus-based stabilizer (C), wherein the content of the aromatic compound (B) in the pellets is 0.001 to 1 mass %, and the content of the phosphorus-based stabilizer (C) is 0.003 to 0.5 mass %. (In the formula, Y is an organic group containing no nitrogen, sulfur, or halogen, or a hydrogen atom. When Y is a hydrogen atom, X is an alkyl group or an aryl group which may have a substituent, and when Y is an organic group containing no nitrogen, sulfur, or halogen, X is an organic group containing no nitrogen, sulfur, or halogen, and in this case, X and Y may be the same or different. g represents an integer of 1 or 2. n represents an integer of 0 to 5, and when n is 2 or more, n Xs may be the same or different. k represents an integer of 1 to 4, and when k is 2 or more, Y is two or more -(CH ２ ) ｇ The OY groups may be the same or different, provided that n+k is 6 or less.

[0003] International Publication No. 2019 / 198321

[0004] Here, resin molded articles used in components requiring transparency, such as power covers, lighting lenses, lighting covers, and light-guiding members, are required to have a low YI value and high transmittance. In this regard, molded articles formed from the resin composition described in Patent Document 1 have excellent YI values. However, depending on the application, an even lower YI value and transmittance may be required. The present invention aims to solve this problem by providing a resin composition, pellets, and molded articles that can provide molded articles with a low YI value and high transmittance.

[0005] In light of the above-mentioned problems, the present inventors have conducted research and found that the above-mentioned problems can be solved by incorporating a compound represented by formula (1) described below. Specifically, the above-mentioned problems have been solved by the following means: <1> A resin composition comprising 0.01 to 1.5 parts by mass of a compound represented by formula (1) per 100 parts by mass of a polycarbonate resin. (In formula (1), R each independently represents a substituted or unsubstituted aliphatic hydrocarbon group having 1 to 10 carbon atoms.) <2> The resin composition according to <1>, in which in formula (1), R each independently represents an unsubstituted alkyl group having 1 to 5 carbon atoms. <3> The resin composition according to <1>, in formula (1), each independently represents a methyl group or an ethyl group. <4> Pellets of the resin composition according to any one of <1> to <3>. <5> A molded article formed from the resin composition according to any one of <1> to <3>. <6> A molded article formed from the pellets according to <4>.

[0006] According to the present invention, it is possible to provide a resin composition, pellets, and molded articles that can provide molded articles with a low YI value.

[0007] Hereinafter, a mode for carrying out the present invention (hereinafter simply referred to as "the present embodiment") will be described in detail. Note that the following present embodiment is an example for explaining the present invention, and the present invention is not limited to only this embodiment. Note that in this specification, the word "to" is used to mean that the numerical values ​​written before and after it are included as lower and upper limits. In this specification, various physical property values ​​and characteristic values ​​are those at 23°C unless otherwise specified. When the measurement methods etc. described in the standards shown in this specification vary depending on the fiscal year, they are based on the standards as of January 1, 2023, unless otherwise specified.

[0008] The resin composition of the present embodiment is characterized by containing 0.01 to 1.5 parts by mass of the compound represented by formula (1) relative to 100 parts by mass of polycarbonate resin. (In formula (1), each R is independently a substituted or unsubstituted aliphatic hydrocarbon group having 1 to 10 carbon atoms.)

[0009] By adopting such a constitution, a resin composition capable of providing a molded article with a low YI value can be obtained. In addition, since a resin composition with excellent extrudability can be obtained, pellet production becomes easy. Furthermore, molded articles with excellent mold deposit resistance can be produced. That is, in this embodiment, an improvement in hue is achieved by blending the compound represented by formula (1). The benzene ring -CH of the compound represented by formula (1) ２ It is believed that the compound represented by formula (1) undergoes a reduction reaction and suppresses the increase in hue. ２ By having an OR structure, the YI value was further reduced. The reason for this is presumably that the para position, which is not prone to condensation reaction, allows for an efficient reduction reaction, thereby preventing an increase in the YI value. The resin composition of this embodiment will now be described.

[0010] <Polycarbonate Resin> The resin composition of this embodiment contains a polycarbonate resin. The polycarbonate resin is not particularly limited as long as it contains an -[O-R-OC(=O)]- unit (where R is an organic group, preferably a hydrocarbon group, more preferably an aliphatic group, an aromatic group, or one containing both an aliphatic group and an aromatic group, and further one having a linear or branched structure) that contains a carbonate bond in the molecular main chain. In this embodiment, the polycarbonate resin is preferably an aromatic polycarbonate resin, and more preferably a polycarbonate resin having a bisphenol skeleton. By using such a polycarbonate resin, better heat resistance and toughness can be achieved in the obtained molded article. In the present embodiment, the polycarbonate resin having a bisphenol skeleton preferably has 90 mol % or more of all structural units that have a bisphenol skeleton, more preferably 90 mol % or more of all structural units that have at least one skeleton of bisphenol A, bisphenol C, and bisphenol AP, and even more preferably 90 mol % or more of all structural units that have a bisphenol A skeleton.

[0011] The viscosity average molecular weight (Mv) of the polycarbonate resin is preferably 10,000 or more, more preferably 12,000 or more, and even more preferably 15,000 or more. By setting it to the lower limit or more, the durability of the obtained molded article tends to be further improved. The upper limit of the viscosity average molecular weight (Mv) of the polycarbonate resin is preferably 50,000 or less, more preferably 40,000 or less, even more preferably 30,000 or less, still more preferably 25,000 or less, and even more preferably 20,000 or less. By setting it to the upper limit or less, the molding processability of the molded article tends to be further improved. The viscosity average molecular weight (Mv) is determined by using methylene chloride as a solvent and an Ubbelohde viscometer to determine the intrinsic viscosity [η] (unit: dL / g) at a temperature of 25°C, and then calculating the viscosity average molecular weight (Mv) using Schnell's viscosity formula, i.e., η = 1.23 × 10 -４ ×Mv ０．８３When two or more types of polycarbonate resins are used, the viscosity average molecular weight is the viscosity average molecular weight of the mixture.

[0012] The method for producing the polycarbonate resin is not particularly limited, and polycarbonate resins produced by the conventionally known phosgene method (interfacial polymerization method) or melt method (ester interchange method) can be used. When the melt method is used, a polycarbonate resin in which the amount of OH groups in the terminal groups has been adjusted can be used.

[0013] The polycarbonate resin used in this embodiment may be a recycled polycarbonate resin product (including recovered products, material recycled products, chemical recycled products, etc.), a rejected product, or a waste material from thermoplastic resin molding.

[0014] In addition to the above, for details of the polycarbonate resin, please refer to the descriptions in paragraphs 0013 to 0041 of JP-A-2021-084942 and paragraphs 0030 to 0035 of JP-A-2021-119211, the contents of which are incorporated herein by reference.

[0015] The content of the polycarbonate resin in the resin composition of this embodiment is preferably 85% by mass or more of the resin composition, more preferably 90% by mass or more, even more preferably 95% by mass or more, even more preferably 97% by mass or more, and even more preferably 98% by mass or more. The upper limit of the content of the polycarbonate resin in the resin composition is the amount such that the total of the polycarbonate resin and the compound represented by formula (1) is 100% by mass. The resin composition of this embodiment may contain only one type of polycarbonate resin, or may contain two or more types. When two or more types are contained, it is preferable that the total amount is within the above range.

[0016] <Compound Represented by Formula (1)> The resin composition of this embodiment contains 0.01 to 1.5 parts by mass of the compound represented by Formula (1) relative to 100 parts by mass of polycarbonate resin. By containing the compound represented by Formula (1), the YI value of the resulting molded article can be reduced. Furthermore, the extrudability of the resin composition of this embodiment can be improved, facilitating the production of pellets. In addition, a resin composition (pellet) with excellent mold deposit resistance during molding can be obtained. (In formula (1), each R is independently a substituted or unsubstituted aliphatic hydrocarbon group having 1 to 10 carbon atoms.)

[0017] In formula (1), each R is independently a substituted or unsubstituted aliphatic hydrocarbon group having 1 to 10 carbon atoms, preferably an unsubstituted aliphatic hydrocarbon group having 1 to 10 carbon atoms. The aliphatic hydrocarbon group is preferably a substituted or unsubstituted alkyl group, more preferably an unsubstituted alkyl group. The alkyl group is preferably a linear or branched alkyl group, more preferably a linear alkyl group. The number of carbon atoms in the aliphatic hydrocarbon group is preferably 7 or less, more preferably 5 or less, and even more preferably 3 or less. More specifically, each R is independently preferably an unsubstituted alkyl group having 1 to 5 carbon atoms, more preferably an unsubstituted alkyl group having 1 to 4 carbon atoms, even more preferably an unsubstituted alkyl group having 1 to 3 carbon atoms, and even more preferably a methyl group or ethyl group. Furthermore, R may be the same or different, but are preferably the same. Examples of substituents that the substituted or unsubstituted aliphatic hydrocarbon group having 1 to 10 carbon atoms may have include aryl groups and halogen atoms, with phenyl groups, fluorine atoms, and chlorine atoms being preferred. In this embodiment, it is preferably unsubstituted.

[0018] In this embodiment, the total number of hydrogen atoms directly bonded to a carbon atom bonded to an aromatic ring of the compound represented by Formula (1) and the total number of hydrogen atoms bonded to a hydroxyl group directly bonded to a carbon atom bonded to an aromatic ring of the compound represented by Formula (1) is preferably 3 or more, more preferably 4 or more. By making the total number equal to or greater than the above-mentioned lower limit, the transmittance in the short wavelength region tends to be improved. Furthermore, the upper limit of the total number of hydrogen atoms directly bonded to a carbon atom bonded to an aromatic ring of the compound represented by Formula (1) and the total number of hydrogen atoms bonded to a hydroxyl group directly bonded to a carbon atom bonded to an aromatic ring of the compound represented by Formula (1) is preferably 6 or less, more preferably 5 or less, and even more preferably 4 or less. By making the total number equal to or less than the above-mentioned upper limit, the transmittance in the short wavelength region tends to be improved. When the resin composition of this embodiment contains two or more compounds represented by Formula (1), the number of protons at the benzyl position of the compound represented by Formula (1) and the concentration of the compound are multiplied, and the sum of these values ​​is taken as the relative proton number.

[0019] Examples of the compound represented by formula (1) are listed below. It goes without saying that the compound represented by formula (1) in this embodiment is not limited to these.

[0020] The content of the compound represented by formula (1) in the resin composition of this embodiment is 0.01 parts by mass or more, preferably 0.05 parts by mass or more, more preferably 0.08 parts by mass or more, even more preferably 0.1 parts by mass or more, still more preferably 0.2 parts by mass or more, and even more preferably 0.5 parts by mass or more, relative to 100 parts by mass of polycarbonate resin. By setting the content at or above the lower limit, transmittance in the short wavelength region tends to be improved. Furthermore, the content of the compound represented by formula (1) is 1.5 parts by mass or less, preferably 1.3 parts by mass or less, more preferably 1.2 parts by mass or less, even more preferably 1.1 parts by mass or less, still more preferably 1.0 parts by mass or less, and even more preferably 0.9 parts by mass or less, relative to 100 parts by mass of polycarbonate resin. By setting the content at or below the upper limit, mold deposits tend to be reduced. The resin composition of this embodiment may contain only one type of compound represented by formula (1), or may contain two or more types. When two or more types are contained, the total amount is preferably within the above range.

[0021] <Other Components> The resin composition of this embodiment may contain other components in addition to those described above, as necessary, as long as the desired physical properties are not significantly impaired. Examples of other components include various resin additives. Examples of resin additives include epoxy compounds and / or oxetane compounds, stabilizers, release agents, UV absorbers, colorants (dyes, pigments), antistatic agents, flame retardants, flame retardant assistants, anti-dripping agents, anti-fogging agents, anti-blocking agents, flow improvers, plasticizers, dispersants, and antibacterial agents. Note that one type of resin additive may be contained, or two or more types may be contained in any combination and ratio.

[0022] <<Epoxy Compound and / or Oxetane Compound>> The resin composition of this embodiment may contain an epoxy compound and / or an oxetane compound. By containing an epoxy compound and / or an oxetane compound, the YI value and the YI value after heating can be reduced, and a molded product with excellent light transmittance in the visible light range can be obtained.

[0023] The epoxy compound refers to a compound containing an epoxy group, and may contain only one epoxy group or two or more epoxy groups in one molecule, but preferably contains one to four, more preferably one to three, and even more preferably two. The oxetane compound refers to a compound containing an oxetanyl group, and may contain only one oxetanyl group or two or more oxetanyl groups in one molecule, but preferably contains one to four, more preferably one to three, and even more preferably two. In this embodiment, it is preferable to contain at least an epoxy compound.

[0024] The molecular weight of the epoxy compound and / or oxetane compound is not particularly limited, but is preferably 100 or more, and is preferably 1500 or less, more preferably 1000 or less, even more preferably 800 or less, and may be 500 or less.

[0025] The epoxy compound and / or oxetane compound is preferably an alicyclic epoxy compound and / or an alicyclic oxetane compound.

[0026] The alicyclic epoxy compound and / or alicyclic oxetane compound used in this embodiment is preferably a compound represented by formula (2), a compound represented by formula (3), or a compound represented by formula (4), more preferably a compound represented by formula (2) and / or a compound represented by formula (4), and even more preferably a compound represented by formula (2). (In formula (2), A 1 represents a divalent organic group.

[0027] In formula (2), A 1 is preferably a hydrocarbon group having 1 to 10 carbon atoms, -O-, -C(=O)-, or a group consisting of a combination of two or more of the above groups, and more preferably an alkylene group having 1 to 10 carbon atoms, -O-, -C(=O)-, or a group consisting of a combination of two or more of the above groups. The alkylene group may be linear, branched, or cyclic, and is preferably linear or branched, and more preferably linear. Preferred examples of the compound represented by formula (2) include the following compounds. Formula (3) (In formula (3), A 2 and A 3 each independently represents a divalent organic group.

[0028] In formula (3), A ２ are each independently preferably a hydrocarbon group having 1 to 10 carbon atoms, more preferably an alkylene group having 1 to 10 carbon atoms, and more preferably an alkylene group having 1 to 3 carbon atoms. ３ is preferably a hydrocarbon group having 1 to 20 carbon atoms, -O-, -C(=O)-, or a group consisting of a combination of two or more of the above groups, more preferably an alkylene group having 1 to 10 carbon atoms, an arylene group having 6 to 12 carbon atoms, -O-, -C(=O)-, or a group consisting of a combination of two or more of the above groups, and even more preferably an alkylene group having 1 to 10 carbon atoms, an arylene group having 6 to 12 carbon atoms, -O-, or a group consisting of a combination of two or more of the above groups. 3 The end (next to the oxygen atom) of is preferably a hydrocarbon group having 1 to 20 carbon atoms, more preferably an alkylene group having 1 to 10 carbon atoms or an arylene group having 6 to 12 carbon atoms, and even more preferably an alkylene group having 1 to 10 carbon atoms. Preferred examples of the compound represented by formula (3) include the following compounds. n is any integer, preferably 1 to 11.

[0029] Formula (4) (In formula (4), A ４ and A ５ R each independently represents a divalent organic group. a is an alkyl group having 1 to 5 carbon atoms, and nb is 0 or 1.

[0030] In formula (4), A 4are each independently preferably a hydrocarbon group having 1 to 20 carbon atoms, -O-, -C(=O)-, or a group consisting of a combination of two or more of the above groups, more preferably an alkylene group having 1 to 10 carbon atoms, an arylene group having 6 to 12 carbon atoms, -O-, -C(=O)-, or a group consisting of a combination of two or more of the above groups, even more preferably an alkylene group having 1 to 10 carbon atoms, an arylene group having 6 to 12 carbon atoms, or a group consisting of a combination of two or more of the above groups, still more preferably an alkylene group having 1 to 10 carbon atoms, even more preferably an alkylene group having 1 to 3 carbon atoms, and still more preferably an ethylene group or a methylene group. 5 is preferably a hydrocarbon group having 1 to 20 carbon atoms, -O-, -C(=O)-, or a group consisting of a combination of two or more of the above groups, more preferably an alkylene group having 1 to 10 carbon atoms, an arylene group having 6 to 12 carbon atoms, -O-, -C(=O)-, or a group consisting of a combination of two or more of the above groups, and even more preferably an alkylene group having 1 to 10 carbon atoms, an arylene group having 6 to 12 carbon atoms, or a group consisting of a combination of two or more of the above groups. 5 The end (next to the oxygen atom) of is preferably a hydrocarbon group having 1 to 20 carbon atoms, more preferably an alkylene group having 1 to 10 carbon atoms or an arylene group having 6 to 12 carbon atoms, even more preferably an alkylene group having 1 to 10 carbon atoms, and still more preferably an alkylene group having 1 to 3 carbon atoms.

[0031] R ａ is preferably an alkyl group having 1 to 3 carbon atoms, and is preferably a methyl group or an ethyl group. nb is preferably 1. Preferred examples of the compound represented by formula (4) include the following compounds.

[0032] In addition to the above, preferred examples of the epoxy compound and / or oxetane compound used in this embodiment include the compounds described in paragraphs 0043 to 0069 of JP-A-2021-038306 and paragraphs 0023 to 0037 of JP-A-2021-031658, the contents of which are incorporated herein by reference.

[0033] When the resin composition of this embodiment contains an epoxy compound and / or an oxetane compound (preferably an epoxy compound), the content thereof is preferably 0.01 parts by mass or more, more preferably 0.05 parts by mass or more, even more preferably 0.1 parts by mass or more, even more preferably 0.2 parts by mass or more, and even more preferably 0.5 parts by mass or more, relative to 100 parts by mass of polycarbonate resin. By ensuring that the content is equal to or greater than the above-mentioned lower limit, long-term heat resistance tends to be improved. Furthermore, the content of the epoxy compound and / or oxetane compound (preferably an epoxy compound) is preferably 1.5 parts by mass or less, more preferably 1.3 parts by mass or less, even more preferably 1.1 parts by mass or less, even more preferably 1.0 part by mass or less, and even more preferably 0.9 parts by mass or less, relative to 100 parts by mass of polycarbonate resin. By ensuring that the content is equal to or less than the above-mentioned upper limit, mold deposits tend to be reduced. The resin composition of the present embodiment may contain only one epoxy compound and oxetane compound (preferably an epoxy compound), or may contain two or more kinds. When two or more kinds are contained, it is preferable that the total amount is in the above range.

[0034] <<Stabilizer>> The resin composition of this embodiment may contain a stabilizer. Examples of stabilizers include heat stabilizers and antioxidants. Examples of stabilizers include phenol-based, amine-based, phosphorus-based, and thioether-based stabilizers. Among these, in this embodiment, it is preferable to contain a phosphorus-based heat stabilizer.

[0035] Any known phosphorus-based heat stabilizer can be used. Specific examples include phosphorus oxoacids such as phosphoric acid, phosphonic acid, phosphorous acid, phosphinic acid, and polyphosphoric acid; metal acid pyrophosphates such as sodium acid pyrophosphate, potassium acid pyrophosphate, and calcium acid pyrophosphate; phosphates of Group 1 or Group 2B metals such as potassium phosphate, sodium phosphate, cesium phosphate, and zinc phosphate; organic phosphate compounds, organic phosphite compounds, and organic phosphonite compounds, with organic phosphite compounds other than the phosphite compounds having a structure represented by formula (P) described below being particularly preferred.

[0036] Examples of the organic phosphite compound include triphenyl phosphite, tris(mononylphenyl) phosphite, tris(mononyl / dinonyl phenyl) phosphite, tris(2,4-di-tert-butylphenyl) phosphite, monooctyldiphenyl phosphite, dioctyl monophenyl phosphite, monodecyldiphenyl phosphite, didecyl monophenyl phosphite, tridecyl phosphite, trilauryl phosphite, tristearyl phosphite, and 2,2-methylenebis(4,6-di-tert-butylphenyl)octyl phosphite. Specific examples of such organic phosphite compounds include "ADK STAB (registered trademark; the same applies hereinafter) 1178," "ADK STAB 2112," and "ADK STAB HP-10" manufactured by ADEKA Corporation; "JP-351," "JP-360," and "JP-3CP" manufactured by Johoku Chemical Industry Co., Ltd.; and "IRGAFOS (registered trademark; the same applies hereinafter) 168" manufactured by BASF.

[0037] The resin composition of this embodiment may or may not contain a phosphite compound having a structure represented by formula (P). In this embodiment, the content of the phosphite compound having a structure represented by formula (P) in the resin composition of this embodiment is preferably 0% by mass or more and less than 0.01% by mass, more preferably less than 0.001% by mass, and even more preferably less than 0.0001% by mass. In this way, by configuring the resin composition to be substantially free of the compound represented by formula (P), a molded article having excellent light transmittance in the visible light region can be obtained.

[0038] Examples of the compound represented by formula (P) include distearyl pentaerythritol diphosphite, bis(decyl)pentaerythritol diphosphite, bis(tridecyl)pentaerythritol diphosphite, and bis(nonylphenyl)pentaerythritol diphosphite.

[0039] In addition to the above, the phosphorus-based heat stabilizer used in this embodiment can be found in paragraphs 0127 to 0133 of JP-A-2022-067329, the contents of which are incorporated herein by reference.

[0040] As the phenol-based antioxidant, a hindered phenol-based antioxidant is preferably used. Specific examples of the hindered phenol-based antioxidant include pentaerythritol tetrakis[3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate], octadecyl-3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate, thiodiethylenebis[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, 4,6-bis(octadecyl) 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-pentylphenyl)ethyl]-4,6-di-tert-pentylphenyl acrylate, and the like.

[0041] Among these, pentaerythritol tetrakis[3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate] and octadecyl-3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate are preferred. Specific examples of such hindered phenol-based antioxidants include "Irganox (registered trademark; the same applies hereinafter) 1010" and "Irganox 1076" manufactured by BASF, and "ADK STAB AO-50" and "ADK STAB AO-60" manufactured by ADEKA Corporation.

[0042] The content of the stabilizer (preferably a phosphorus-based stabilizer other than a phosphite compound having a structure represented by formula (P)) in the resin composition of this embodiment is usually 0.001 part by mass or more, preferably 0.005 part by mass or more, more preferably 0.01 part by mass or more, and usually 1 part by mass or less, preferably 0.5 part by mass or less, more preferably 0.3 part by mass or less, relative to 100 parts by mass of the polycarbonate resin. By setting the content of the stabilizer within the above range, the effect of adding the stabilizer can be more effectively exerted. The resin composition of this embodiment may contain only one type of stabilizer, or may contain two or more types. When two or more types are contained, it is preferable that the total amount be in the above range.

[0043] <<Release Agent>> The resin composition of this embodiment may contain a release agent. Adding a release agent can further improve releasability. Examples of release agents include aliphatic carboxylic acids, salts of aliphatic carboxylic acids, esters of aliphatic carboxylic acids and alcohols, aliphatic hydrocarbon compounds with a number-average molecular weight of 200 to 15,000, polysiloxane-based silicone oils, ketone waxes, and light amides. Of these, aliphatic carboxylic acids, salts of aliphatic carboxylic acids, and esters of aliphatic carboxylic acids and alcohols are preferred. For details about release agents, see paragraphs 0055 to 0061 of JP 2018-095706 A, the contents of which are incorporated herein by reference. When the resin composition of this embodiment contains a release agent, the content thereof is preferably 0.01 to 3 mass% of the resin composition. The resin composition of this embodiment may contain only one type of release agent, or two or more types. When two or more types are contained, the total amount is preferably within the above range.

[0044] <Physical Properties of Resin Composition> The resin composition of this embodiment preferably has a low YI value when molded into a 300 mm long optical path molded article. Specifically, the YI value when the resin composition of this embodiment is molded into a 300 mm long optical path molded article is preferably 17.3 or less, more preferably 16.5 or less, even more preferably 15.0 or less, and even more preferably 14.5 or less. Furthermore, although 0 is the ideal lower limit of the YI value, a value of 1.0 or more, even 5.0 or more, and particularly 10.0 or more will sufficiently satisfy the required performance. Such a low YI value is achieved by incorporating a compound represented by formula (1). The YI value is measured according to the method described in the Examples below.

[0045] The resin composition of this embodiment, when molded into a 300 mm long optical path molded article, preferably has a light transmittance at a wavelength of 400 nm of 42.0% or more, more preferably 43.0% or more, more preferably 44.0% or more, even more preferably 45.0% or more, and even more preferably 47.0% or more. There is no particular upper limit for the light transmittance at a wavelength of 400 nm, but 99.0% or less is practical, and even 95.0% or less sufficiently meets the required performance. The resin composition of this embodiment, when molded into a 300 mm long optical path molded article, preferably has a light transmittance at a wavelength of 420 nm of 56.0% or more, more preferably 57.0% or more, more preferably 58.0% or more, even more preferably 59.0% or more, and even more preferably 60.0% or more. Furthermore, although there is no particular upper limit for the light transmittance at a wavelength of 420 nm, a practical value is 99.0% or less, and even if it is 95.0% or less, the required performance is sufficiently met. When the resin composition of this embodiment is molded into a 300 mm long optical path molded product, the light transmittance at a wavelength of 500 nm is preferably 65.0% or more, more preferably 67.0% or more, more preferably 68.0% or more, even more preferably 70.0% or more, and even more preferably 75.0% or more. Furthermore, although there is no particular upper limit for the light transmittance at a wavelength of 500 nm, a practical value is 99.0% or less, and even if it is 95.0% or less, the required performance is sufficiently met. The YI value and light transmittance are measured according to the methods described in the Examples below.

[0046] <Method of Manufacturing Resin Composition> The method of manufacturing the resin composition of this embodiment is not limited, and a wide variety of known methods for manufacturing resin compositions can be used. For example, a method can be used in which the polycarbonate resin, the compound represented by formula (1), and other components that are added as needed are premixed using various mixers such as a tumbler or a Henschel mixer, and then melt-kneaded using a mixer such as a Banbury mixer, a roll, a Brabender mixer, a single-screw kneading extruder, a twin-screw kneading extruder, or a kneader. The melt-kneading temperature is not particularly limited, but is usually in the range of 240 to 320°C.

[0047] <Molded Article> The molded article of this embodiment is formed from the resin composition or pellets of this embodiment. The above-mentioned resin composition (e.g., pellets) is molded into a molded article by various molding methods. The shape of the molded article is not particularly limited and can be appropriately selected depending on the use and purpose of the molded article. Examples include film-like, rod-like, cylindrical, ring-like, circular, elliptical, polygonal, irregular-shaped, hollow, frame-like, box-like, panel-like, and button-like shapes.

[0048] The method for molding the molded article is not particularly limited, and conventionally known molding methods can be used, such as injection molding, injection compression molding, extrusion molding, profile extrusion, transfer molding, blow molding, gas-assisted blow molding, blow molding, extrusion blow molding, IMC (in-mold coating molding), rotational molding, multilayer molding, two-color molding, insert molding, sandwich molding, foam molding, and pressure molding. The resin composition of this embodiment is particularly suitable for molded articles obtained by injection molding, injection compression molding, and extrusion molding. However, it goes without saying that the resin composition of this embodiment is not limited to molded articles obtained by these methods.

[0049] The molded article of this embodiment can be widely used for molded articles containing polycarbonate resin, particularly optical components. Specifically, it is preferably used in electrical and electronic equipment / components, office automation equipment / components, information terminal equipment / components, machine parts, home appliances, vehicle parts, building materials, various containers, leisure goods / miscellaneous goods, lighting equipment, etc., and more specifically, it is preferably used for power covers, lighting lenses, lighting covers, light guiding members, etc. More specifically, it can be used for light guides and lenses that guide light from light sources such as LEDs in vehicle headlamps (headlamps) or rear lamps, fog lamps, etc. for automobiles or motorcycles. For uses of the resin composition of this embodiment, in addition to the above, the descriptions of 0098 to 0105 of JP 2020-189992 A can be referred to, the contents of which are incorporated herein by reference.

[0050] The present invention will be explained in more detail below with reference to examples. The materials, amounts used, ratios, treatment contents, treatment procedures, etc. shown in the following examples can be changed as appropriate without departing from the spirit of the present invention. Therefore, the scope of the present invention is not limited to the specific examples shown below. If the measuring instruments used in the examples are difficult to obtain due to discontinuation or the like, measurements can be made using other instruments with equivalent performance.

[0051] 1. Raw Materials The materials shown in Table 1 below were used.

[0052] 2. Examples 1-2, Comparative Examples 1-3 <Compounds> The components (polycarbonate resin and the compound represented by formula (1) or its substitute) listed in Table 1 were blended so that the content of the compound represented by formula (1) or its substitute was the ratio listed in Table 2 (amount relative to 100 parts by mass of polycarbonate resin, units: parts by mass), and the mixture was uniformly mixed in a tumbler mixer to obtain a mixture. This mixture was fed to a single-screw extruder "VS40-32V" manufactured by Tanabe Plastics Machinery Co., Ltd., and kneaded under conditions of a screw rotation speed of 80 rpm, a discharge rate of 20 kg / hr, and a barrel temperature of 250°C, and extruded in the form of a strand from the tip of the extrusion nozzle. The extrudate was quenched in a water bath and cut and pelletized using a pelletizer to obtain pellets of the resin composition.

[0053] <Extrudability> The extrudability during pellet production was checked. Evaluation was carried out by five experts and judged by majority vote. A: Excellent extrudability during pellet production. B: Poor extrudability during pellet production.

[0054] <Mold deposits> Each resin composition (pellet) obtained above was dried in a hot air circulation dryer at 120°C for 4 to 8 hours, and then molded into a 300 mm long optical path molded product (6 mm x 4 mm x 300 mm, L / d = 50) at a temperature of 280°C using an injection molding machine (FANUC Corporation "S-2000i 150B"). At this time, mold deposits on the mold during injection molding were evaluated. The evaluation was made by five experts and judged by majority vote. A: Small mold deposits. B: Large mold deposits.

[0055] <Measurement of Light Transmittance> Each resin composition (pellet) obtained above was dried at 120°C for 4 to 8 hours in a hot air circulation dryer, and then molded into a 300 mm long optical path molded product (6 mm x 4 mm x 300 mm, L / d = 50) at a temperature of 280°C using an injection molding machine (FANUC Corporation "S-2000i 150B"). The 300 mm long optical path molded product obtained above was used as a test piece, and the light transmittance was measured at wavelengths of 400 nm, 420 nm, 440 nm, 460 nm, 480 nm, and 500 nm over a 300 mm length using a long optical path spectrophotometer with a C light source and a 2°C field of view. The long optical path spectrophotometer used was an "ASA1" manufactured by Nippon Denshoku Industries Co., Ltd. However, since molding was not possible for Comparative Examples 1 and 2, light transmittance was not measured.

[0056] <Measurement of YI Value> Each resin composition (pellet) obtained above was dried at 120°C for 4 to 8 hours in a hot air circulation dryer, and then molded into a 300 mm long optical path molded product (6 mm x 4 mm x 300 mm, L / d = 50) at a temperature of 280°C using an injection molding machine (FANUC Corporation's "S-2000i 150B"). The YI (Yellow Index) value of this molded product was measured over a 300 mm length using a long optical path spectrophotometer with a C light source and a 2°C field of view. The long optical path spectrophotometer used was an "ASA1" manufactured by Nippon Denshoku Industries Co., Ltd. However, since Comparative Examples 1 and 2 could not be molded, the YI value was not measured.

[0057]

[0058] In the above table, "number of protons at benzyl positions (including OH groups)" refers to the sum of the number of hydrogen atoms directly bonded to the carbon atom bonded to the aromatic ring of the compound represented by formula (1) and the number of hydrogen atoms bonded to the hydroxyl group directly bonded to the carbon atom bonded to the aromatic ring of the compound represented by formula (1). As is clear from the above results, the resin composition of this embodiment produced molded articles with low YI values. Furthermore, the molded articles produced from the resin composition of this embodiment exhibited excellent extrudability and good mold deposits. Furthermore, they also exhibited high light transmittance in the visible range. On the other hand, when orthoxylylene glycol or metaxylylene glycol was used, the production of resin composition pellets was difficult. Furthermore, injection molding was not possible (Comparative Examples 1 and 2). Furthermore, when benzyl alcohol was used (Comparative Example 3), the YI value of the resulting molded article was high. Furthermore, there was also a large amount of mold deposit.

Claims

1. Per 100 parts by mass of polycarbonate resin, A resin composition comprising 0.01 to 1.5 parts by mass of a compound represented by formula (1), A light-guiding member formed from a resin composition, wherein the content of a phosphite compound having a structure represented by the following formula (P) is 0% by mass or more and less than 0.001% by mass of the resin composition: 【Chemistry 1】 (In formula (1), each R is independently a substituted or unsubstituted aliphatic hydrocarbon group having 1 to 10 carbon atoms.) 【Chemistry 2】

2. 2. The light-guiding member according to claim 1, wherein in the formula (1), R's each independently represent an unsubstituted alkyl group having 1 to 5 carbon atoms.

3. The light-guiding member according to claim 1 , wherein in the formula (1), each R is independently a methyl group or an ethyl group.

4. Per 100 parts by mass of polycarbonate resin, A resin composition comprising 0.01 to 1.5 parts by mass of a compound represented by formula (1), A resin composition for forming a light-guiding member, comprising a phosphite compound having a structure represented by the following formula (P), the content of which is 0% by mass or more and less than 0.001% by mass of the resin composition: 【Chemistry 3】 (In formula (1), each R is independently a substituted or unsubstituted aliphatic hydrocarbon group having 1 to 10 carbon atoms.) 【Chemistry 4】

5. The resin composition for forming a light-guiding member described in claim 4, wherein in the formula (1), R is each independently an unsubstituted alkyl group having 1 to 5 carbon atoms.

6. The resin composition for forming a light-guiding member described in claim 4, wherein in the formula (1), R is each independently a methyl group or an ethyl group.

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