JP2023051536A - Resin composition, molding, method for producing pellet, and light transmittance improver - Google Patents

Abstract

To provide a resin composition that can provide a molding having high light transmittance, a molding formed from the resin composition, and a method for producing a pellet, and to provide a light transmittance improver for improving the light transmittance of thermoplastic resin.SOLUTION: A resin composition comprises a thermoplastic resin 100 pts.mass and a non-aromatic organic aluminum complex 0.08-2.50 mass ppm.SELECTED DRAWING: None

Description

TECHNICAL FIELD The present invention relates to a resin composition, a molded article, a method for producing pellets, and a light transmittance improver.

BACKGROUND ART Conventionally, thermoplastic resins such as polycarbonate resins have been widely used for various purposes due to their excellent various performances. Among them, thermoplastic resins, particularly polycarbonate resins, are actively used in members requiring transparency, such as power covers, illumination lenses, illumination covers, and light guide members.
For example, Patent Document 1 describes an aromatic polycarbonate resin composition containing an aromatic polycarbonate resin (A), a phosphorus antioxidant (B), a fatty acid ester (C) and a specific aromatic compound (D). 0.01 to 0.1 parts by weight of the phosphorus antioxidant (B) and 0.01 to 0.5 parts by weight of the fatty acid ester (C) with respect to 100 parts by weight of the aromatic polycarbonate resin (A). and 0.0001 parts by weight or more and less than 0.05 parts by weight of a specific aromatic compound (D). It also describes that a molded article obtained from such a resin composition has a high light transmittance.

JP 2021-120458 A

As described above, resin compositions with high light transmittance are known, but as the use of thermoplastic resins increases, new resin compositions with high light transmittance are in demand.
An object of the present invention is to solve such problems, and a resin composition capable of providing a molded article having high light transmittance, a molded article formed from the resin composition, and production of pellets Regarding the method. It also relates to a light transmittance improver for improving the light transmittance of a thermoplastic resin.

Based on the above problems, the present inventor conducted studies and found that light transmittance can be improved by blending a small amount of a non-aromatic organoaluminum complex into a thermoplastic resin. Specifically, the above problems have been solved by the following means.
<1> A resin composition containing 100 parts by mass of a thermoplastic resin and 0.08 to 2.50 ppm by mass of a non-aromatic organoaluminum complex.
<2> The resin composition according to <1>, wherein the non-aromatic organoaluminum complex comprises an acetylacetone aluminum complex.
<3> The resin composition according to <1> or <2>, wherein the thermoplastic resin contains an amorphous resin.
<4> The resin composition according to <1> or <2>, wherein the thermoplastic resin contains an aromatic polycarbonate resin.
<5> A molded article formed from the resin composition according to any one of <1> to <4>.
<6> A method for producing pellets, comprising melt-kneading a composition containing 100 parts by mass of a thermoplastic resin and 0.08 to 2.50 ppm by mass of a non-aromatic organoaluminum complex.
<7> A light transmittance improver which is an additive for improving the light transmittance of a resin and which contains a non-aromatic organoaluminum complex.
<8> The light transmittance improver according to <7>, wherein the non-aromatic organoaluminum complex is an acetylacetone aluminum complex.
<9> The light transmittance improver according to <7> or <8>, wherein the resin is an amorphous thermoplastic resin.
<10> The light transmittance improver according to any one of <7> to <9>, wherein the resin is an aromatic polycarbonate resin.

ADVANTAGE OF THE INVENTION By this invention, it became possible to provide the resin composition which can provide the molded object with a high light transmittance, the molded object formed from the said resin composition, and the manufacturing method of a pellet. Also, it has become possible to provide a light transmittance improver for improving the light transmittance of a thermoplastic resin.

EMBODIMENT OF THE INVENTION Hereinafter, the form (only henceforth "this embodiment") for implementing this invention is demonstrated in detail. In addition, the following embodiment is an example for explaining the present invention, and the present invention is not limited only to this embodiment.
In this specification, the term "~" is used to mean that the numerical values before and after it are included as the lower limit and the upper limit.
In this specification, various physical property values and characteristic values are at 23° C. unless otherwise specified.
In the present specification, the number average molecular weight is a polystyrene equivalent value measured by GPC (gel permeation chromatography) method.
If the standards shown in this specification differ from year to year in terms of measurement methods, etc., the standards as of January 1, 2021 shall be used unless otherwise specified.

The resin composition of the present embodiment is characterized by containing 100 parts by mass of a thermoplastic resin and 0.08 to 2.50 mass ppm of a non-aromatic organoaluminum complex. With such a configuration, the light transmittance (in particular, the total light transmittance) of the thermoplastic resin can be improved. Furthermore, this effect can be maintained at a high level even when various resin additives are added. Also, even if a non-aromatic organoaluminum complex is blended, an increase in the YI value can be effectively suppressed.

<Thermoplastic resin>
The resin composition of this embodiment contains a thermoplastic resin.
Examples of thermoplastic resins include polycarbonate resin (PC resin); polystyrene resin (PS resin); acrylic resin; polyethylene resin (PE resin), polypropylene resin (PP resin), cyclic cycloolefin resin (COP resin), cyclic cycloolefin Polyolefin resin such as copolymer (COC) resin; Polyamide resin (PA resin); Polyimide resin (PI resin); Polyetherimide resin (PEI resin); Polyurethane resin (PU resin); Polyphenylene ether resin (PPE resin); polyphenylene sulfide resin (PPS resin); polysulfone resin (PSU resin); polymethacrylate resin (PMMA resin); More preferred, aromatic polycarbonate resin is even more preferred.

The thermoplastic resin used in the present embodiment may be a crystalline thermoplastic resin or an amorphous thermoplastic resin, but preferably contains an amorphous thermoplastic resin. Since amorphous thermoplastic resins are transparent, they are suitable for applications requiring improved light transmittance. However, even a crystalline thermoplastic resin may be used as a transparent material, for example, when it is molded without being crystallized. In such a case, a crystalline thermoplastic resin is also preferably used as the resin contained in the resin composition of the present embodiment. Further, in the present embodiment, a blend form of an amorphous thermoplastic resin and a crystalline thermoplastic resin may be used.

The thermoplastic resin in the present embodiment is preferably 85% by mass or more, more preferably 90% by mass or more, still more preferably 95% by mass or more, and particularly preferably 97% by mass or more is an amorphous thermoplastic resin ( aromatic polycarbonate resin).

Polycarbonate resins are -[OR-OC(=O)]-units (R is an organic group, preferably a hydrocarbon group, more preferably an aliphatic group, an aromatic It is not particularly limited as long as it contains an aliphatic group, a group containing both an aliphatic group and an aromatic group, and a group having a linear or branched structure. In the present embodiment, the polycarbonate resin is preferably an aromatic polycarbonate resin, 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 present embodiment, in the polycarbonate resin having a bisphenol skeleton, 90 mol% or more of all structural units are preferably structural units having a bisphenol skeleton, and 90 mol% or more of all structural units are bisphenol A-derived structural units. is more preferable.

Also, the viscosity average molecular weight (Mv) of the polycarbonate resin is preferably 10,000 or more, more preferably 12,000 or more, and still more preferably 15,000 or more. When the content is at least the above lower limit, 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, still more preferably 30,000 or less, and still more preferably 25 , 000 or less. By setting the content to the above 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 using an Ubbelohde viscometer to determine the intrinsic viscosity [η] (unit: dL/g) at a temperature of 25°C. 1.23×10 ⁻⁴ ×Mv ^0.83 , means a value calculated from.
When two or more polycarbonate resins are used, the viscosity-average molecular weight of the mixture is used.

The method for producing the polycarbonate resin is not particularly limited, and one produced by a conventionally known phosgene method (interfacial polymerization method) or melting method (transesterification method) can be used. Moreover, when the melting method is used, a polycarbonate resin in which the amount of OH groups in terminal groups is adjusted can be used.

In addition to the above, the details of the polycarbonate resin can be referred to paragraphs 0013 to 0041 of JP-A-2021-084942 and paragraphs 0030-0035 of JP-A-2021-119211, the contents of which are incorporated herein. .

The content of the thermoplastic resin (preferably polycarbonate resin) in the resin composition of the present embodiment is preferably 85% by mass or more of the resin composition, more preferably 90% by mass or more, and 95% by mass. % or more, more preferably 97 mass % or more, and even more preferably 98 mass % or more. The upper limit of the content of the thermoplastic resin in the resin composition is an amount such that the total content of the thermoplastic resin (preferably polycarbonate resin) and the non-aromatic organoaluminum complex is 100% by mass.
The resin composition of the present embodiment may contain only one type of thermoplastic resin (preferably polycarbonate resin), or may contain two or more types. When two or more types are included, the total amount is preferably within the above range.

<Non-aromatic organoaluminum complex>
The resin composition of the present embodiment contains a non-aromatic organoaluminum complex in a predetermined proportion. Light transmittance can be improved by including the non-aromatic organoaluminum complex in a predetermined proportion.
A non-aromatic organoaluminum complex refers to an organoaluminum complex that does not contain an aromatic ring (an aromatic hydrocarbon ring and an aromatic heterocyclic ring). An aromatic organoaluminum complex containing an aromatic ring is used as a colorant for thermoplastic resins, but when such a colorant is blended, the total light transmittance usually decreases. Also, the YI value may be high. In this embodiment, the light transmittance is successfully increased by blending the non-aromatic organoaluminum complex with the thermoplastic resin in a very small proportion. In particular, it is effective in maintaining this function even when other resin additives are added.

（式（１）中、Ｒ¹～Ｒ³は、それぞれ独立に、水素原子または有機基である。＊はアルミニウムとの配位部位である。）
Ｒ¹およびＲ³は、それぞれ独立に、炭素数１～１２の有機基であることが好ましく、炭素数１～１０のアルキル基、炭素数６～１２のアリール基、または、炭素数２～１１のアルコキシ基であることがより好ましく、炭素数１～１０のアルキル基であることがさらに好ましく、メチル基またはエチル基であることが一層好ましく、メチル基であることがより一層好ましい。
Ｒ²は、水素原子または炭素数１～１２の有機基であることが好ましく、水素原子、炭素数１～１０のアルキル基、炭素数６～１２のアリール基、または、炭素数２～１１のアルコキシ基であることがより好ましく、水素原子、または、炭素数１～１０のアルキル基であることがさらに好ましく、水素原子、メチル基またはエチル基であることが一層好ましく、水素原子またはメチル基であることがより一層好ましく、水素原子であることがさらに一層好ましい。 The ligand constituting the non-aromatic organoaluminum complex is not particularly limited as long as it is non-aromatic and serves as a ligand for aluminum. is preferred, and a ligand represented by the following formula (1) is more preferred.
formula (1)

(In Formula (1), R ¹ to R ³ are each independently a hydrogen atom or an organic group. * is a coordination site with aluminum.)
R ¹ and R ³ are each independently preferably an organic group having 1 to 12 carbon atoms, such as an alkyl group having 1 to 10 carbon atoms, an aryl group having 6 to 12 carbon atoms, or 2 to 11 carbon atoms. is more preferably an alkoxy group of, more preferably an alkyl group having 1 to 10 carbon atoms, still more preferably a methyl group or an ethyl group, and even more preferably a methyl group.
R ² is preferably a hydrogen atom or an organic group having 1 to 12 carbon atoms, and is a hydrogen atom, an alkyl group having 1 to 10 carbon atoms, an aryl group having 6 to 12 carbon atoms, or an aryl group having 2 to 11 carbon atoms. It is more preferably an alkoxy group, more preferably a hydrogen atom or an alkyl group having 1 to 10 carbon atoms, still more preferably a hydrogen atom, a methyl group or an ethyl group, and a hydrogen atom or a methyl group. It is more preferable to be one, and it is still more preferable to be a hydrogen atom.

The non-aromatic organoaluminum complex of the present embodiment preferably contains an acetylacetonate aluminum complex. The acetylacetonate aluminum complex is preferably a trivalent complex.

Further, the acetylacetonate aluminum complex in the present embodiment is intended to include not only a single acetylacetone aluminum complex but also a mixed ligand complex composed of acetylacetone and other ligands. However, the acetylacetonate aluminum complex in this embodiment is preferably a single acetylacetone aluminum complex.

The content of the non-aromatic organoaluminum complex (preferably acetylacetone aluminum complex) in the resin composition of the present embodiment is 0.08 mass ppm or more, and 0.09 mass ppm or more, relative to 100 parts by mass of the thermoplastic resin. is preferably By making it equal to or higher than the above lower limit, the light transmittance of the molded article to be obtained tends to be further improved. In addition, the upper limit of the content of the non-aromatic organoaluminum complex (preferably acetylacetone aluminum complex) is 2.50 mass ppm or less and 1.50 mass ppm or less with respect to 100 parts by mass of the thermoplastic resin. is preferably 0.50 mass ppm or less, and even more preferably 0.20 mass ppm or less. By making it equal to or less than the above upper limit, there is a tendency that the YI value of the resulting molded article can be made lower.
The resin composition of the present embodiment may contain only one type of non-aromatic organoaluminum complex (preferably acetylacetone aluminum complex), or may contain two or more types. When two or more types are included, the total amount is preferably within the above range.

<Stabilizer>
Stabilizers include heat stabilizers and antioxidants.
Stabilizers also include phenol-based, amine-based, phosphorus-based, thioether-based, and the like. Among them, in the present embodiment, phosphorus-based heat stabilizers and/or phenol-based antioxidants are preferred.

Any known phosphorus-based heat stabilizer can be used. Specific examples include phosphorus oxo acids such as phosphoric acid, phosphonic acid, phosphorous acid, phosphinic acid, and polyphosphoric acid; acid pyrophosphate metal salts 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, zinc phosphate; is particularly preferred.

Examples of organic phosphite compounds include triphenylphosphite, tris(monononylphenyl)phosphite, tris(monononyl/dinonylphenyl)phosphite, tris(2,4-di-tert-butylphenyl)phosphite, monooctyl Diphenylphosphite, dioctylmonophenylphosphite, monodecyldiphenylphosphite, didecylmonophenylphosphite, tridecylphosphite, trilaurylphosphite, tristearylphosphite, 2,2-methylenebis(4,6-di- tert-butylphenyl)octyl phosphite and the like.
Specific examples of such organic phosphite compounds include, for example, "ADEKA STAB (registered trademark; hereinafter the same) 1178", "ADEKA STAB 2112", and "ADEKA STAB HP-10" manufactured by Johoku Chemical Industry Co., Ltd. "JP-351", "JP-360", "JP-3CP", BASF's "Irgafos (registered trademark; hereinafter the same) 168", and the like.

As the phenolic antioxidant, a hindered phenolic antioxidant is preferably used.
Specific examples of hindered phenol antioxidants 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-dimethyl ethyl)-4-hydroxyphenyl]methyl]phosphate, 4,6-bis(octylthiomethyl)-o-cresol, ethylenebis(oxyethylene)bis[3-(5-tert-butyl-4-hydroxy-m- tolyl)propionate], hexamethylenebis[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. mentioned.

Among them, pentaerythritol tetrakis [3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate] and octadecyl-3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate preferable. Specific examples of such hindered phenol antioxidants include, for example, "Irganox (registered trademark; hereinafter the same) 1010" and "Irganox 1076" manufactured by BASF, "ADEKA STAB AO-50" manufactured by ADEKA, " Adekastab AO-60” and the like.

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 with respect to 100 parts by mass of the thermoplastic resin. or more, and 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 setting the content of the stabilizer within the above range, the effect of addition of the stabilizer is exhibited more effectively.
The resin composition of the present embodiment may contain only one stabilizer, or may contain two or more stabilizers. When two or more types are included, the total amount is preferably within the above range.

<Flame retardant>
The resin composition of this embodiment may contain a flame retardant. By including a flame retardant, the flame retardancy of the resulting molded article can be further improved.
Examples of flame retardants include metal salt flame retardants, organosilicon flame retardants, phosphorus flame retardants, inorganic filler flame retardants, and halogen flame retardants. In this embodiment, when a polycarbonate resin is used as the thermoplastic resin, a metal salt-based flame retardant is preferred.

The metal contained in the metal salt-based flame retardant is preferably an alkali metal or alkaline earth metal, more preferably an alkali metal, and still more preferably sodium, potassium, or cesium.

Examples of metal salt-based flame retardants include metal salts of organic sulfonates, metal salts of organic sulfonamides, metal salts of organic carboxylic acids, metal salts of organic borates, and metal salts of organic phosphates. Among them, metal salts of organic sulfonates, metal salts of organic sulfonamides, and metal salts of organic phosphates are preferred, and metal salts of organic sulfonates are particularly preferred.

As the organic sulfonic acid metal salt, the organic sulfonic acid metal salts described in paragraphs 0099 to 0107 of JP-A-2014-058660 can be referred to, and the contents thereof are incorporated herein.
Examples of the metal salt-based flame retardant include Megafac F114P (trade name) manufactured by DIC, Biowet C4 (trade name) manufactured by LANXESS, IHT-FR2 (trade name) manufactured by Insight High Technology, KSS-FR (trade name manufactured by Arichem), and the like. be.

As the halogen-based flame retardant, the halogen-based flame retardants described in paragraphs 0095 to 0112 of JP-A-2020-114674 can be referred to, and the contents thereof are incorporated herein.

As the phosphorus-based flame retardant, the phosphorus-based flame retardants described in paragraphs 0051 to 0072 of JP-A-2019-059813 can be referred to, and the contents thereof are incorporated herein.

When the resin composition of the present embodiment contains a flame retardant, its content is preferably 0.01 parts by mass or more with respect to 100 parts by mass of the thermoplastic resin, although it depends on the type of flame retardant. may be 0.1 parts by mass or more, 1 part by mass or more, or 10 parts by mass or more. Further, the upper limit of the content of the flame retardant is preferably 20 parts by mass or less with respect to 100 parts by mass of the thermoplastic resin. It may be 3 parts by mass or less.
The resin composition of the present embodiment may contain only one flame retardant, or may contain two or more flame retardants. When two or more types are included, the total amount is preferably within the above range.

<Release agent>
The resin composition of this embodiment may contain a release agent.
Release agents include, for example, 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, and polysiloxane-based silicone oils. , ketone wax, light amide, etc., preferably aliphatic carboxylic acids, salts of aliphatic carboxylic acids, esters of aliphatic carboxylic acids and alcohols, and more preferably salts of aliphatic carboxylic acids.
Details of the release agent can be referred to paragraphs 0055 to 0061 of JP-A-2018-095706, and the contents thereof are incorporated herein.
When the resin composition of the present embodiment contains a release agent, the content thereof is preferably 0.05 to 3% by mass, more preferably 0.1 to 0.8% by mass in the resin composition. is more preferable, and 0.1 to 0.6% by mass is even more preferable.
The resin composition of the present embodiment may contain only one release agent, or may contain two or more release agents. When two or more types are included, the total amount is preferably within the above range.

<Ultraviolet absorber>
The resin composition of this embodiment may contain an ultraviolet absorber. By containing an ultraviolet absorber, the weather resistance of the resin composition can be improved, and the deterioration of transparency can be prevented by improving the weather resistance.

UV absorbers include, for example, inorganic UV absorbers such as cerium oxide and aluminum oxide; An ultraviolet absorber etc. are mentioned. Among these, organic ultraviolet absorbers are preferred, and benzotriazole compounds are more preferred. By selecting the organic ultraviolet absorber, the thermoplastic resin composition of the present invention has good transparency and mechanical properties.

Specific examples of benzotriazole compounds include 2-(2'-hydroxy-5'-methylphenyl)benzotriazole, 2-[2'-hydroxy-3',5'-bis(α,α-dimethylbenzyl ) phenyl]-benzotriazole, 2-(2′-hydroxy-3′,5′-di-tert-butyl-phenyl)-benzotriazole, 2-(2′-hydroxy-3′-tert-butyl-5′ -methylphenyl)-5-chlorobenzotriazole, 2-(2'-hydroxy-3',5'-di-tert-butyl-phenyl)-5-chlorobenzotriazole), 2-(2'-hydroxy-3 ',5'-di-tert-amyl)-benzotriazole, 2-(2'-hydroxy-5'-tert-octylphenyl)benzotriazole, 2,2'-methylenebis[4-(1,1,3, 3-tetramethylbutyl)-6-(2N-benzotriazol-2-yl)phenol], among which 2-(2′-hydroxy-5′-tert-octylphenyl)benzotriazole, 2,2 '-methylenebis[4-(1,1,3,3-tetramethylbutyl)-6-(2N-benzotriazol-2-yl)phenol] is preferred, especially 2-(2'-hydroxy-5'-tert -octylphenyl)benzotriazole is preferred.
Specific examples of such benzotriazole compounds include "Seesorb 701 (S-701)", "Seesorb 705 (S-705)", "Seesorb 703 (S-703)" and "Seesorb 703 (S-703)" manufactured by Shipro Kasei Co., Ltd. Seesorb 702 (S-702)", "Seesorb 704 (S-704)", "Seesorb 709 (S-709)", "Biosorb 520", "Biosorb 582", "Biosorb 580", "Biosorb 583”, “Chemisorb 71” and “Chemisorb 72” manufactured by Chemipro Kasei Co., Ltd., “Cyasorb UV5411” manufactured by Cytec Industries, “LA-32”, “LA-38”, “LA-36”, “LA-” manufactured by ADEKA 34”, “LA-31”, BASF “tinuvin P”, “tinuvin 234”, “tinuvin 326”, “tinuvin 327”, “tinuvin 328” and the like.

Details of the benzophenone compound, salicylate compound, cyanoacrylate compound, oxanilide compound, and malonic acid ester compound can be referred to paragraphs 0089 to 0093 of JP-A-2021-001309, the contents of which are incorporated herein. be

When the resin composition of the present embodiment contains an ultraviolet absorber, the content thereof is preferably 0.001 parts by mass or more, and 0.01 parts by mass or more with respect to 100 parts by mass of the thermoplastic resin. is more preferable, and 0.1 parts by mass or more is even more preferable. By setting the amount to the above lower limit or more, the effect of adding the ultraviolet absorber tends to be effectively exhibited. The upper limit of the content of the ultraviolet absorber is preferably 3 parts by mass or less, more preferably 1 part by mass or less, and 0.5 parts by mass or less with respect to 100 parts by mass of the thermoplastic resin. More preferably, it is 0.4 parts by mass or less. By making the content equal to or less than the upper limit, contamination of the mold due to mold deposits or the like can be effectively prevented.
The resin composition of the present embodiment may contain only one type of ultraviolet absorber, or may contain two or more types thereof. When two or more types are included, the total amount is preferably within the above range.

<Other ingredients>
The resin composition of the present embodiment may optionally contain other components than those mentioned above as long as the desired physical properties are not significantly impaired. Examples of other components include various resin additives.
Resin additives include, for example, coloring agents (dyes, pigments), antistatic agents, flame retardant aids, anti-dripping agents, anti-fogging agents, anti-blocking agents, fluidity improvers, plasticizers, dispersants, and antibacterial agents. etc. One resin additive may be contained, or two or more resin additives may be contained in any combination and ratio.
The resin composition of the present embodiment can have a configuration that does not substantially contain a coloring agent. “Substantially free” means that the content of the colorant in the resin composition is less than 0.1% by mass, preferably less than 0.01% by mass, and less than 0.001% by mass. It is even more preferable to have Furthermore, with respect to 100 parts by mass of the thermoplastic resin contained in the resin composition, the content of the coloring agent is more preferably less than 1 ppm by mass, even more preferably less than 0.1 ppm by mass, and 0 It is even more preferably less than 0.08 mass ppm, particularly more preferably less than 0.01 mass ppm, and even more particularly less than 0.001 mass ppm. The lower limit may be 0, but will be substantially below the detection limit.

<Physical properties of the resin composition>
The resin composition of the present embodiment has a high total light transmittance improvement rate (light transmittance improvement ratio). Specifically, the resin composition of the present embodiment has a total light transmittance higher than the total light transmittance when the composition A obtained by removing the non-aromatic organoaluminum complex from the resin composition of the present embodiment is molded to a thickness of 12 mm. The total light transmittance is higher when the resin composition of the embodiment is molded to a thickness of 12 mm. More specifically, (total light transmittance of a 12 mm thick test piece molded from the resin composition of the present embodiment) / (total light transmittance of a 12 mm thick test piece molded from composition A) is , is greater than 1.000, preferably 1.001 or more, more preferably 1.003 or more, further preferably 1.005 or more. The upper limit of the above value is preferably as high as possible, but even if it is, for example, 1.100 or less, it has sufficient practical value.
The resin composition of the present embodiment can have a low YI value. For example, the YI value when the resin composition of the present embodiment is molded to a thickness of 12 mm can be 6.0 or less, 5.0 or less, or 3.5 or less, It can also be 3.0 or less. Although the lower limit of the YI value is ideally 0, a value of 0.1 or more sufficiently satisfies the required performance.
The light transmittance enhancement ratio and the YI value are measured according to the description of the examples below.

<Production of resin composition>
The method for producing the resin composition of the present embodiment is not limited, and a wide range of known methods for producing a resin composition can be employed. Other components are mixed in advance using various mixers such as tumblers and Henschel mixers, and then melt-kneaded with mixers such as Banbury mixers, rolls, Brabender, single-screw kneading extruders, twin-screw kneading extruders, and kneaders. method. The melt-kneading temperature is not particularly limited, but is usually in the range of 240 to 320°C.
This embodiment preferably discloses a method for producing pellets, which comprises melt-kneading a composition containing 0.08 to 2.50 ppm by mass of a non-aromatic organoaluminum complex with respect to 100 parts by mass of a thermoplastic resin. .
Here, the thermoplastic resin and the non-aromatic metal organic complex contained in the composition, and the preferred ranges of these contents are the thermoplastic resin and the non-aromatic It is the same as the metal-organic complex and the content thereof. The composition may also contain other components described in the description of the resin composition of the present embodiment.

<Molded body>
The molded article of this embodiment is formed from the resin composition of this embodiment. The above-described resin composition (for example, pellets) is molded by various molding methods to form molded articles. The shape of the molded article is not particularly limited, and can be appropriately selected according to the application and purpose of the molded article. , odd-shaped products, hollow products, frame-shaped products, box-shaped products, panel-shaped products, button-shaped products, and the like.

The method for molding the molded article is not particularly limited, and conventionally known molding methods can be employed, such as injection molding, injection compression molding, extrusion molding, profile extrusion, transfer molding, blow molding, Gas-assisted blow molding method, blow molding method, extrusion blow molding method, IMC (in-mold coating molding) method, rotational molding method, multi-layer molding method, two-color molding method, insert molding method, sandwich molding method, foam molding method , pressure molding, and the like. In particular, the resin composition of the present embodiment is suitable for moldings obtained by injection molding, injection compression molding, and extrusion molding. However, it goes without saying that the resin composition of the present embodiment is not limited to the molded articles obtained by these methods.

The molded article of the present embodiment can be widely used for molded articles containing a thermoplastic resin, particularly for applications requiring transparency.
Specifically, it is preferably used for electrical and electronic equipment/parts, OA equipment/parts, information terminal equipment/parts, machine parts, home appliances, vehicle parts, building materials, various containers, leisure goods/miscellaneous goods, lighting equipment, and the like. More specifically, it is preferably used for electric power covers, illumination lenses, illumination covers, light guide members, and the like.

<Light transmittance improver>
This embodiment discloses a light transmittance improver, which is a resin additive for improving the light transmittance of a thermoplastic resin and which contains a non-aromatic organoaluminum complex. Such a resin additive is particularly used as a total light transmittance improver.
The non-aromatic organoaluminum complex is preferably an acetylacetone aluminum complex. The details of the non-aromatic organoaluminum complex are the same as the details of the non-aromatic organoaluminum complex described in the description of the resin composition of the present embodiment.

The light transmittance improver of the present embodiment is intended to improve the light transmittance of a thermoplastic resin. In particular, a resin for improving the light transmittance of an amorphous thermoplastic resin, more preferably a polycarbonate resin It is preferably used as an additive. The details of the thermoplastic resin are the same as the details of the thermoplastic resin described in the description of the resin composition of the present embodiment.
The light transmittance improver of this embodiment is preferably used in a proportion of 0.08 to 2.50 ppm by mass with respect to 100 parts by mass of the thermoplastic resin. The more preferable range is the same as the preferable range of the content of the non-aromatic organoaluminum complex in the resin composition of the present embodiment described above.
The light transmittance improver of the present embodiment is preferably blended with a thermoplastic resin and melt-kneaded for use.

EXAMPLES The present invention will be described more specifically with reference to examples below. The materials, usage amounts, ratios, processing details, processing procedures, etc. shown in the following examples can be changed as appropriate without departing from the gist of the present invention. Accordingly, the scope of the present invention is not limited to the specific examples shown below.
If the measuring instruments and the like used in the examples are discontinued and difficult to obtain, other instruments having equivalent performance can be used for measurement.

1. Raw Materials Raw materials shown in Table 1 below were used.

2. Examples 1-4, Comparative Examples 1-5
<Compound>
Each component described in Table 1 is blended so that the ratio described in Table 2 (all parts are expressed in parts by mass, but (B1) is expressed in ppm by mass), and mixed uniformly in a tumbler mixer to obtain a mixture. rice field. This mixture is supplied to a twin-screw extruder ("TEX26SX" manufactured by Shibaura Kikai Co., Ltd.), kneaded under the conditions of a screw rotation speed of 150 rpm, a discharge rate of 20 kg / hour, and a barrel temperature of 280 ° C., and extruded into a strand from the tip of the extrusion nozzle. The extrudate was quenched in a water bath, cut and pelletized using a pelletizer to obtain pellets of the resin composition.

<Light transmittance improvement ratio>
For each resin composition obtained above, injection molding was performed using a J85AD injection molding machine manufactured by Japan Steel Works, Ltd. under the conditions of a resin temperature of 280 ° C. and a mold temperature of 80 ° C., and a length of 50 × 50 mm and a wall thickness were molded. 12 mm block pieces were obtained. Using this block piece as a test piece, a haze meter (NDH4000) manufactured by Nippon Denshoku Industries Co., Ltd. was used to measure the total light transmittance of the test piece with a thickness of 12 mm with a D65 light source according to ASTM-D1003.
Furthermore, the total light transmittance of the test piece not containing the non-aromatic organoaluminum complex (light transmittance improver) was measured, and the ratio of the total light transmittance of the test piece to which the non-aromatic organoaluminum complex was added was calculated. It was calculated as a light transmittance improvement ratio. That is, for Comparative Examples 1 to 4 and Examples 1 to 3, the light transmittance improvement ratio was calculated based on Comparative Example 1, and for Comparative Examples 5 and 4, the light transmittance improvement ratio was calculated based on Comparative Example 5. was calculated.

<YI value>
Using the block piece having a length of 50 × 50 mm and a thickness of 12 mm obtained above as a test piece, using a spectral color difference meter (SE6000) manufactured by Nippon Denshoku Industries Co., Ltd., C light source 2 ° field of view, transmission method, YI (Yellow Index) values were measured.

As is clear from the above results, the resin composition of the present invention can improve the light transmittance and effectively suppress the increase in the YI value by blending the non-aromatic organoaluminum complex at a predetermined ratio. (Comparison between Examples 1-3 and Comparative Examples 1-4). Further, the improvement in the light transmittance did not change even when the additive was added, and the same tendency was observed (comparison between Example 4 and Comparative Example 5).

Claims (10)

100 parts by mass of a thermoplastic resin;
0.08 to 2.50 ppm by mass of a non-aromatic organoaluminum complex,
Resin composition. 2. The resin composition of claim 1, wherein the non-aromatic organoaluminum complex comprises an acetylacetone aluminum complex. The resin composition according to claim 1 or 2, wherein the thermoplastic resin contains an amorphous resin. 3. The resin composition according to claim 1, wherein said thermoplastic resin comprises an aromatic polycarbonate resin. A molded article formed from the resin composition according to any one of claims 1 to 4. A method for producing pellets, comprising melt-kneading a composition containing 100 parts by mass of a thermoplastic resin and 0.08 to 2.50 ppm by mass of a non-aromatic organoaluminum complex. A light transmittance improver which is an additive for improving the light transmittance of a resin and which contains a non-aromatic organoaluminum complex. 8. The light transmittance enhancer according to claim 7, wherein the non-aromatic organoaluminum complex is an acetylacetone aluminum complex. The light transmittance improver according to claim 7 or 8, wherein the resin is an amorphous thermoplastic resin. The light transmittance improver according to any one of claims 7 to 9, wherein the resin is an aromatic polycarbonate resin.