JP3618458B2 - Polycarbonate resin composition - Google Patents

Description

【００１４】
式中、Ｒ^１ 及びＲ ^２ は、それぞれ、Ｈ、Ｃ１〜３０のアルキル基、シクロアルキル基、アルケニル基、アリール基、アリールアルキル基、アリールアルケニル基、ヒドロキシ基、アルコキシ基、アシル基またはアシロキシ基であり、アリール基、アリールアルキル基及びアリールアルケニル基の核には置換基として、Ｃ１〜１０のアルキル基またはハロゲン基を有することができ、ｍは３以上の整数、好ましくは３〜３０の整数、より好ましくは３〜１５の整数である。
該オキシメチレン単位を有する化合物または置換オキシメチレン単位を有する化合物は、１種類で、あるいは２種以上を混合して使用しても良い。
【００１５】
一般式（１）で示される化合物の具体例としては、トリオキサン、パラアルデヒド、メタアクロレイン、メタアルデヒド等が挙げられる。
本発明における置換環状エーテル化合物は、下記一般式（３）で示される化合物である。
【００１６】
【化５】

【００１７】
式中、Ｒ^７及びＲ^８は、それぞれ、Ｈ、Ｃ１〜３０のアルキル基、シクロアルキル基、アルケニル基、アリール基、アリールアルキル基、アリールアルケニル基、ヒドロキシ基、アルコキシ基、アシル基またはアシロキシ基であり、アリール基、アリールアルキル基及びアリールアルケニル基の核には置換基として、Ｃ１〜１０のアルキル基またはハロゲン基を有することができ、Ｒ^９及びＲ^１０は、それぞれ、Ｈ、Ｃ１〜３０のアルキル基、シクロアルキル基、アルケニル基、アリール基、アリールアルキル基、アリールアルケニル基またはアシル基であり、アリール基、アリールアルキル基及びアリールアルケニル基の核には置換基として、Ｃ１〜１０のアルキル基またはハロゲン基を有することができ、ｎは１以上の整数、好ましくは１〜１０の整数、より好ましくは１〜７の整数である。
該置換環状エーテル化合物は、１種類で、あるいは２種類以上を混合して使用しても良い。
【００１８】
一般式（３）で示される化合物の具体例としては、２、５−ジメトキシテトラヒドロフラン、２、５−ジエトキシテトラヒドロフラン、２、５−ジフェノキシテトラヒドロフラン、２、５−ジメトキシ−３−ホルミルテトラヒドロフラン、２、５−ジメトキシ−２、５−ジヒドロフラン、２、６−ジメトキシテトラヒドロピラン、２、６−ジエトキシテトラヒドロピラン等が挙げられる。
【００１９】
本発明におけるオキシメチレン単位を有する化合物、置換オキシメチレン単位を有する化合物または置換環状エーテル化合物の配合量は、ポリカーボネート樹脂１００重量部に対して、０．０１〜５重量部である。配合量が０．０１重量部未満では、電離放射線照射による黄変度の改良効果が不十分となりやすく、５重量部を超えると機械物性が低下しやすい。オキシメチレン単位を有する化合物、置換オキシメチレン単位を有する化合物または置換環状エーテル化合物の配合量は、黄変度の改良効果と機械物性とのバランスの点から、ポリカーボネート樹脂１００重量部に対して、好ましくは０．０５〜３重量部である。
本発明におけるオキシ基またはカルボニル基を有する芳香族化合物は、下記一般式（４）または（５）で示される化合物である。
【００２０】
【化６】

【００２１】
式中、Ｒ^１１、Ｒ^１３及びＲ^１５は、それぞれ、Ｃ１〜１０のアルキル基、アルコキシ基、アルコキシアルキル基、アリールアルコキシアルキル基、−ＣＨ_２ＯＨ基またはハロゲン基であり、Ｒ^１４は、Ｃ１〜１５のアルキレン基、アルケニレン基、アリーレン基、アルキレンジオキシ基またはアリーレンジアルキレンオキシ基であり、アリーレン基及びアリーレンジアルキレンオキシ基の核には置換基として、Ｃ１〜１０のアルキル基またはハロゲン基を有することができ、Ｘ^１、Ｘ^２及びＸ^３は、それぞれ、−Ｏ−、−ＣＨＲ^１６−Ｏ−、−ＣＯ−、−ＣＨＲ^１７−ＣＯ−、−ＣＯ−ＣＯ−又は−ＣＯ−Ｃ（ＯＲ^１８）_２−であり、Ｒ^１２、Ｒ^１６、Ｒ^１７及びＲ^１８は、それぞれ、Ｈ、Ｃ１〜３０のアルキル基、シクロアルキル基、アルケニル基、アリール基、アリールアルキル基、アリールアルケニル基、ヒドロキシ基、アルコキシ基、アリールアルコキシ基、アリールアルキルアルコキシ基、アシル基またはアリールアシル基であり、アリール基、アリールアルキル基、アリールアルケニル基、アリールアルコキシ基、アリールアルキルアルコキシ基及びアリールアシル基の核には置換基として、Ｃ１〜１０のアルキル基またはハロゲン基を有することができ、また、同一核にあるＲ^１２を有する置換基が、２個以上存在する場合は該置換基はそれぞれのＲ^１２を介して共有結合で結ばれていても良く、ｈ、ｊ及びｋは、それぞれ、０〜５の整数であり、ｉは１〜６の整数であり、ｈとｉの合計は１〜６である。
該オキシ基あるいはカルボニル基を有する芳香族化合物を有する化合物は、１種類で、あるいは２種以上を混合して使用しても良い。
【００２２】
一般式（４）で示される化合物の具体例としては、ジフェニルエーテル、アリルフェニルエーテル、ジベンジルエーテル、ベンジルメチルエーテル、ベンジルフェニルエーテル、ベンジルナフチルエーテル、１、４−ベンゾジオキサン、１、２ーメチレンジオキシベンゼン、ピペロニルアルコール、ベンゾフェノン、ジベンジルケトン、ベンジルメチルケトン、ベンジルフェニルケトン、ベンジルトリルケトン、ベンジルナフチルケトン、ジベンゾイル、ベンゾイルシクロブタン、ベンゾイルプロパン、ベンゾイン、ベンゾインエチルエーテル、１、２ージベンゾイルベンゼン、１、４ービスメトキシメチルベンゼン、フェニル酢酸ベンジルエステル、安息香酸ベンジルエステル、フタル酸ベンジルブチルエステル、フタル酸ジシクロヘキシルエステル、ベンジルジメチルケタール等が挙げられる。
【００２３】
一般式（５）で示される化合物の具体例としては、ジベンゾイルメタン、ジベンゾイルプロパン、１、２ージベンジロキシエタン、ヒドロキノンジベンジルエーテル、エチレングリコールジベンゾエート等が挙げられる。
【００２４】
本発明におけるオキシ基またはカルボニル基を有する芳香族化合物の配合量は、ポリカーボネート樹脂１００重量部に対して、０．０１〜５重量部である。配合量が０．０１重量部未満では、電離放射線照射による黄変度の改良効果が不十分となりやすく、５重量部を超えると機械物性が低下しやすい。オキシ基またはカルボニル基を有する芳香族化合物の配合量は、黄変度の改良効果と機械物性とのバランスの点から、ポリカーボネート樹脂１００重量部に対して、好ましくは０．０５〜３重量部である。
【００２５】
オキシメチレン単位を有する化合物、置換オキシメチレン単位を有する化合物または置換環状エーテル化合物とオキシ基またはカルボニル基を有する芳香族化合物の混合比は、特に制限はないが、好ましくは重量比で１０／９０〜９０／１０である。
上述したように、ポリカーボネート樹脂に、特定量のオキシメチレン単位を有する化合物、置換オキシメチレン単位を有する化合物または置換環状エーテル化合物及びオキシ基またはカルボニル基を有する芳香族化合物を配合することにより、物性が低下することなく、黄変度の少ないポリカーボネート樹脂組成物が得られる。
【００２６】
本発明において、ポリカーボネート樹脂に、オキシメチレン単位を有する化合物、置換オキシメチレン単位を有する化合物または置換環状エーテル化合物及びオキシ基またはカルボニル基を有する芳香族化合物を配合する方法としては、最終成形品を成形する直前までの任意の段階で、当業者に周知の種々の方法によって行うことができる。例えば、タンブラー、ヘンシェルミキサー等で混合する方法や、フィーダーにより定量的に押出機ホッパーに供給して混合する方法等がある。
【００２７】
本発明の組成物には更にその目的に応じ、所望の特性を付与する他の添加剤を添加しても良い。例えば、ハロゲン化合物、リン化合物、スルホン酸金属塩等の難燃剤、アンチモン化合物、ジルコニウム化合物等の難燃助剤、ポリテトラフルオロエチレン、珪素化合物等の着火時の滴下防止剤、エラストマー等の耐衝撃改良剤、酸化防止剤、熱安定剤、紫外線吸収剤、帯電防止剤、可塑剤、離型剤、滑剤、相溶化剤、発泡剤、ガラス繊維、ガラスビーズ、ガラスフレーク、炭素繊維、繊維状マグネシウム、チタン酸カリウムウィスカー、セラミックウィスカー、マイカ、タルク等の補強剤、充填剤、染顔料等を、一種又は二種以上添加含有させる事も可能である。
【００２８】
本発明の組成物は、射出成形、ブロー成形等、慣用の成形方法に従って、所望の成形品とすることができる。本発明の耐電離放射線性ポリカーボネート樹脂組成物を適用することが望まれている医療用成形品としては、具体的には、人工透析器、人工肺、麻酔用吸入装置、静脈用コネクタ及び付属品、血液遠心分離ボウル、外科用具、手術室用具、酸素を血液に供給するチューブ、チューブの接続具、心臓プローブ並びに注射器、外科用具、手術室器具、静脈注射液等を入れる容器等が挙げられる。
【００２９】
以下、本発明を実施例により更に詳細に説明するが、本発明はその要旨を超えない限り、以下の実施例に限定されるものではない。
【実施例】
〔実施例１〜５、比較例１〜３〕
ポリカーボネート樹脂（ユーピロン Ｓ−２０００、三菱エンジニアリングプラスチックス株式会社製。粘度平均分子量２５，０００。）１００重量部と、表−１に記載のオキシメチレン単位を有する化合物、置換オキシメチレン単位を有する化合物または置換環状エーテル化合物及びオキシ基またはカルボニル基を有する芳香族化合物を、表−１に記載の比率で、タンブラーにて混合し、各々φ４０ｍｍ一軸ベント式押出機を用いて、バレル温度２７０℃で押出してペレットを得た。
このペレットを熱風乾燥器中で、１２０℃にて５時間以上乾燥した後、樹脂温度２７０℃、金型温度８０℃にて５０ｍｍφ×３ｍｍ厚みの試験片を射出成形した。
この成形片を用い、コバルト６０γ線を２５キログレイ（ｋＧｙ）照射し、照射前後の黄色度を、ＪＩＳ Ｋ７１０３に従って、スガ試験機（株）製の色差計ＳＭ−３−ＣＨにて測定し、黄変度（ΔＹＩ）を求めた。結果を表−１に示す。
【００３０】
【表１】

【００３１】
【発明の効果】
本発明の組成物は、物性の劣化が少なく殺菌のために照射される電離放射線による色調の変化が少ない。従って、電離放射線照射滅菌が行われる医療用製品、医療用装置、医療用装置の部材等の用途に有用である。[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a polycarbonate resin composition containing a compound having an oxymethylene unit, a compound having a substituted oxymethylene unit or a substituted cyclic ether compound, and an aromatic compound having an oxy group or a carbonyl group.
[0002]
[Prior art]
Polycarbonate resins are widely used as medical products because of their excellent mechanical strength, impact strength, heat resistance, transparency and high safety.
These medical products are usually completely sterilized when used. Specific examples include high-pressure steam sterilization, ethylene oxide gas (EOG) sterilization, and sterilization by irradiation with ionizing radiation such as gamma rays and electron beams. Among these, the high-pressure steam sterilization method has a high energy cost and further requires a drying step after the sterilization treatment. In addition, EOG sterilization has EOG itself toxic and environmental problems related to disposal. Therefore, recently, ionizing radiation (generally gamma rays) irradiation sterilization methods that are relatively inexpensive and can be processed at low temperature and dry type are often used.
However, the polycarbonate resin has a disadvantage that it is discolored yellow when it is irradiated with ionizing radiation during sterilization, which impairs the product value particularly in medical use.
[0003]
As a method for solving such drawbacks, for example, JP-A-2-55062 discloses a method of blending a halogen-containing polycarbonate resin, and JP-A-5-179127 discloses a method of blending a nuclear brominated phthalic acid derivative. Although each is described, since the composition contains halogen, metal corrosion is likely to occur, and it was necessary to use a special metal for the molding machine or the like.
[0004]
Further, as a method of using a sulfur compound, JP-A-1-229052 discloses a method of blending thioalcohols, JP-A-2-115260 discloses a method of blending thioethers, JP-A-2-49058, In JP-A-4-36343 and JP-A-6-166807, a method of blending a compound having a mercapto group is used. In JP-A-5-209120, an aromatic compound having a polyalkylene oxide and a sulfonate ester substituent is used. In addition, JP-A-6-93192 and JP-A-6-248170 each describe a method of using a compound having a sulfide group, but in any case, the yellowing inhibiting effect is insufficient. Or there is a problem that a bad odor is generated during use and the environment during molding is deteriorated.
[0005]
Further, JP-A-61-215651 discloses a method of compounding a boron compound, JP-A-62-135556 discloses a method of compounding a polyether polyol or an alkyl ether thereof, and JP-A-2-232258 discloses a method of incorporating benzyl. JP-A-2-132147 describes a method of blending an alcohol derivative, and a method of blending itaconic acid, benzaldehyde dimethyl acetal, benzaldehyde propylene glycol acetal, etc., but the yellowing inhibiting effect is insufficient. In addition, there is a problem that, if the addition amount is increased to obtain a sufficient effect, other physical properties are adversely affected.
[0006]
[Problems to be solved by the invention]
An object of the present invention is to provide a polycarbonate resin composition with little deterioration in physical properties and very little yellowing upon sterilization by ionizing radiation irradiation.
[0007]
[Means for Solving the Problems]
The present invention has been made to solve the above-mentioned problems, and the gist thereof is that a compound having an oxymethylene unit, a compound having a substituted oxymethylene unit, or a substituted cyclic ether compound 0 in 100 parts by weight of a polycarbonate resin. .01～5 parts, and Ri Na by blending aromatics 0.01 to 5 parts by weight having an oxy group or a carbonyl group, a compound having a chemical compound or substituent oxymethylene units having oxymethylene units, the general is a compound represented by the formula (1), substituted cyclic ether compounds, consists in the polycarbonate resin composition you wherein a compound represented by the general formula (3).
[0008]
Hereinafter, the present invention will be described in detail.
The polycarbonate resin in the present invention is a polymer or copolymer of a thermoplastic aromatic polycarbonate which may be branched by reacting an aromatic dihydroxy compound or a small amount thereof with a diester of phosgene or carbonic acid. It is.
[0009]
Examples of aromatic dihydroxy compounds are 2,2-bis (4-hydroxyphenyl) propane (= bisphenol A), 2,2-bis (3,5-dibromo-4-hydroxyphenyl) propane (= tetrabromobisphenol A). ), Bis (4-hydroxyphenyl) methane, 1,1-bis (4-hydroxyphenyl) ethane, 2,2-bis (4-hydroxyphenyl) butane, 2,2-bis (4-hydroxyphenyl) octane, 2,2-bis (4-hydroxy-3-methylphenyl) propane, 1,1-bis (3-tert-butyl-4-hydroxyphenyl) propane, 2,2-bis (4-hydroxy-3,5- Dimethylphenyl) propane, 2,2-bis (3-bromo-4-hydroxyphenyl) propane, 2,2-bis (3,5-dichloro-4) Hydroxyphenyl) propane, 2,2-bis (3-phenyl-4-hydroxyphenyl) propane, 2,2-bis (3-cyclohexyl-4-hydroxyphenyl) propane, 1,1-bis (4-hydroxyphenyl) Bis (hydroxyaryl) alkanes exemplified by -1-phenylethane, bis (4-hydroxyphenyl) diphenylmethane, etc .; 1,1-bis (4-hydroxyphenyl) cyclopentane, 1,1-bis (4-hydroxy) Bis (hydroxyaryl) cycloalkanes exemplified by phenyl) cyclohexane and the like; dihydroxydiaryl ethers exemplified by 4,4′-dihydroxydiphenyl ether, 4,4′-dihydroxy-3,3′-dimethyldiphenyl ether and the like; 4,4'-dihydroxydiphenylsulfur Dihydroxydiaryl sulfides such as 4,4′-dihydroxy-3,3′-dimethyldiphenyl sulfide; 4,4′-dihydroxydiphenyl sulfoxide, 4,4′-dihydroxy-3,3′-dimethyl Dihydroxy diaryl sulfoxides exemplified by diphenyl sulfoxide and the like; dihydroxy diaryl sulfones exemplified by 4,4′-dihydroxydiphenyl sulfone, 4,4′-dihydroxy-3,3′-dimethyldiphenyl sulfone and the like; hydroquinone, resorcin, 4,4′-dihydroxydiphenyl and the like. These aromatic dihydroxy compounds may be used alone or in combination of two or more. Among these, 2,2-bis (4-hydroxyphenyl) propane is particularly preferably used.
[0010]
In order to obtain a branched aromatic polycarbonate resin, phloroglysin, 2,6-dimethyl-2,4,6-tri (4-hydroxyphenyl) -3-heptene, 4,6-dimethyl-2,4, 6-tri (4-hydroxyphenyl) -2-heptene, 1,3,5-tri (2-hydroxyphenyl) benzol, 1,1,1-tri (4-hydroxyphenyl) ethane, 2,6-bis ( A polyhydroxy compound exemplified by 2-hydroxy-5-methylbenzyl) -4-methylphenol, α, α ′, α ″ -tri (4-hydroxyphenyl) -1,3,5-triisopropylbenzene, or the like; 3,3-bis (4-hydroxyaryl) oxindole (= isatin bisphenol), 5-chlorisatin bisphenol, 5,7-dichloroisatin bis Phenol, 5-bromoisatin bisphenol, or the like may be used.
[0011]
In the case of a phosgene polycarbonate, a terminal terminator or a molecular weight modifier may be used. Examples of the terminal terminator or the molecular weight regulator include compounds having a monovalent phenolic hydroxyl group. In addition to normal phenol, pt-butylphenol, tribromophenol, etc., long-chain alkylphenols, aliphatic carboxylic acid chlorides are used. And aliphatic carboxylic acids, hydroxybenzoic acid alkyl esters, alkyl ether phenols and the like. In the polycarbonate resin used in the present invention, one kind may be used, or two or more kinds may be mixed and used.
[0012]
The molecular weight of the polycarbonate resin in the present invention is 10,000 to 100,000, preferably 15,000 to 50 in terms of viscosity average molecular weight converted from the solution viscosity measured at a temperature of 25 ° C. using methylene chloride as a solvent. , 000.
The compound having an oxymethylene unit or the compound having a substituted oxymethylene unit in the present invention is a compound represented by the following general formula (1) or (2).
[0013]
[Formula 4]

[0014]
In which R ¹ And R ² Are H, C1-30 alkyl group, cycloalkyl group, alkenyl group, aryl group, arylalkyl group, arylalkenyl group, hydroxy group, alkoxy group, acyl group or acyloxy group, respectively, aryl group, arylalkyl group The nucleus of the group and the arylalkenyl group can have a C1-10 alkyl group or a halogen group as a substituent , m is an integer of 3 or more, preferably an integer of 3-30, more preferably 3-15. It is an integer.
The compound having an oxymethylene unit or the compound having a substituted oxymethylene unit may be used alone or in combination of two or more.
[0015]
Specific examples of the compound represented by the general formula (1) include trioxane, paraaldehyde, methacrolein, and metaldehyde .
The substituted cyclic ether compound in the present invention is a compound represented by the following general formula (3).
[0016]
[Chemical formula 5]

[0017]
In the formula, each of R ⁷ and R ⁸ is H, a C1-30 alkyl group, a cycloalkyl group, an alkenyl group, an aryl group, an arylalkyl group, an arylalkenyl group, a hydroxy group, an alkoxy group, an acyl group, or an acyloxy group. The nucleus of the aryl group, arylalkyl group and arylalkenyl group can have a C1-10 alkyl group or a halogen group as a substituent, and R ⁹ and R ¹⁰ are H, C1-30, respectively. An alkyl group, a cycloalkyl group, an alkenyl group, an aryl group, an arylalkyl group, an arylalkenyl group or an acyl group, and the nucleus of the aryl group, arylalkyl group and arylalkenyl group has a C1-10 alkyl as a substituent. Group or a halogen group, and n is an integer of 1 or more, preferably Is an integer of 1 to 10, more preferably an integer of 1 to 7.
The substituted cyclic ether compound may be used alone or in combination of two or more.
[0018]
Specific examples of the compound represented by the general formula (3) include 2,5-dimethoxytetrahydrofuran, 2,5-diethoxytetrahydrofuran, 2,5-diphenoxytetrahydrofuran, 2,5-dimethoxy-3-formyltetrahydrofuran, , 5-dimethoxy-2,5-dihydrofuran, 2,6-dimethoxytetrahydropyran, 2,6-diethoxytetrahydropyran and the like.
[0019]
The compounding quantity of the compound which has an oxymethylene unit in this invention, the compound which has a substituted oxymethylene unit, or a substituted cyclic ether compound is 0.01-5 weight part with respect to 100 weight part of polycarbonate resin. If the blending amount is less than 0.01 parts by weight, the effect of improving the degree of yellowing by irradiation with ionizing radiation tends to be insufficient, and if it exceeds 5 parts by weight, the mechanical properties are likely to deteriorate. The compounding amount of the compound having an oxymethylene unit, the compound having a substituted oxymethylene unit or the substituted cyclic ether compound is preferably from 100 parts by weight of the polycarbonate resin from the viewpoint of the balance between the effect of improving yellowing and the mechanical properties. Is 0.05 to 3 parts by weight.
The aromatic compound having an oxy group or a carbonyl group in the present invention is a compound represented by the following general formula (4) or (5).
[0020]
[Chemical 6]

[0021]
In the formula, R ¹¹ , R ¹³ and R ¹⁵ are each a C1-10 alkyl group, alkoxy group, alkoxyalkyl group, arylalkoxyalkyl group, —CH ₂ OH group or halogen group, and R ¹⁴ is C1. -15 alkylene group, alkenylene group, arylene group, alkylenedioxy group or arylene alkyleneoxy group, and a C1-10 alkyl group or halogen group as a substituent at the nucleus of the arylene group and arylene alkyleneoxy group. X ¹ , X ² and X ³ are each —O—, —CHR ¹⁶ —O—, —CO—, —CHR ¹⁷ —CO—, —CO—CO— or —CO—C, respectively. (OR ¹⁸ ) ₂ —, wherein R ¹² , R ¹⁶ , R ¹⁷ and R ¹⁸ are H, a C1-30 alkyl group, A cycloalkyl group, an alkenyl group, an aryl group, an arylalkyl group, an arylalkenyl group, a hydroxy group, an alkoxy group, an arylalkoxy group, an arylalkylalkoxy group, an acyl group or an arylacyl group; an aryl group, an arylalkyl group, an arylalkenyl group; The nucleus of the group, arylalkoxy group, arylalkylalkoxy group and arylacyl group can have a C1-10 alkyl group or a halogen group as a substituent, and a substituent having R ^{12 in the} same nucleus When two or more are present, the substituents may be covalently bonded through the respective R ¹² , h, j and k are each an integer of 0 to 5, and i is 1 to 1 6 is an integer, and the sum of h and i is 1-6.
The compounds having an aromatic compound having an oxy group or a carbonyl group may be used alone or in combination of two or more.
[0022]
Specific examples of the compound represented by the general formula (4) include diphenyl ether, allyl phenyl ether, dibenzyl ether, benzyl methyl ether, benzyl phenyl ether, benzyl naphthyl ether, 1,4-benzodioxane, 1,2-methylenedi Oxybenzene, piperonyl alcohol, benzophenone, dibenzyl ketone, benzyl methyl ketone, benzyl phenyl ketone, benzyl tolyl ketone, benzyl naphthyl ketone, dibenzoyl, benzoylcyclobutane, benzoylpropane, benzoin, benzoin ethyl ether, 1,2-dibenzoyl Benzene, 1,4-bismethoxymethylbenzene, phenylacetic acid benzyl ester, benzoic acid benzyl ester, phthalic acid benzylbutyl ester, phthalic acid dicyclohexyl ester Esters, benzyl dimethyl ketal.
[0023]
Specific examples of the compound represented by the general formula (5) include dibenzoylmethane, dibenzoylpropane, 1,2-dibenzyloxyethane, hydroquinone dibenzyl ether, ethylene glycol dibenzoate and the like.
[0024]
The compounding quantity of the aromatic compound which has an oxy group or a carbonyl group in this invention is 0.01-5 weight part with respect to 100 weight part of polycarbonate resin. If the blending amount is less than 0.01 parts by weight, the effect of improving the degree of yellowing by irradiation with ionizing radiation tends to be insufficient, and if it exceeds 5 parts by weight, the mechanical properties are likely to deteriorate. The blending amount of the aromatic compound having an oxy group or a carbonyl group is preferably 0.05 to 3 parts by weight with respect to 100 parts by weight of the polycarbonate resin from the viewpoint of the balance between the yellowing improvement effect and the mechanical properties. is there.
[0025]
The mixing ratio of the compound having an oxymethylene unit, the compound having a substituted oxymethylene unit or the substituted cyclic ether compound and the aromatic compound having an oxy group or a carbonyl group is not particularly limited, but is preferably 10/90 to 10/90 by weight ratio. 90/10.
As described above, by blending a polycarbonate resin with a specific amount of a compound having an oxymethylene unit, a compound having a substituted oxymethylene unit or a substituted cyclic ether compound, and an aromatic compound having an oxy group or a carbonyl group, the physical properties are improved. A polycarbonate resin composition having a low degree of yellowing can be obtained without lowering.
[0026]
In the present invention, as a method of blending a polycarbonate resin with a compound having an oxymethylene unit, a compound having a substituted oxymethylene unit or a substituted cyclic ether compound, and an aromatic compound having an oxy group or a carbonyl group, the final molded product is molded. It can be carried out by various methods well known to those skilled in the art at any stage up to just before. For example, there are a method of mixing with a tumbler, a Henschel mixer or the like, a method of quantitatively supplying to an extruder hopper with a feeder, and a method of mixing.
[0027]
Depending on the purpose of the composition of the present invention, other additives that impart desired characteristics may be added. For example, flame retardants such as halogen compounds, phosphorus compounds and sulfonic acid metal salts, flame retardant aids such as antimony compounds and zirconium compounds, anti-dripping agents upon ignition of polytetrafluoroethylene and silicon compounds, impact resistance of elastomers, etc. Improver, antioxidant, heat stabilizer, ultraviolet absorber, antistatic agent, plasticizer, mold release agent, lubricant, compatibilizer, foaming agent, glass fiber, glass beads, glass flake, carbon fiber, fibrous magnesium Further, reinforcing agents such as potassium titanate whiskers, ceramic whiskers, mica and talc, fillers, dyes and pigments, and the like may be added or contained.
[0028]
The composition of the present invention can be formed into a desired molded article according to a conventional molding method such as injection molding or blow molding. Specific examples of the medical molded article to which the ionizing radiation-resistant polycarbonate resin composition of the present invention is desired include an artificial dialyzer, an artificial lung, an inhalation device for anesthesia, a connector for veins, and accessories. , Blood centrifuge bowls, surgical tools, operating room tools, tubes for supplying oxygen to blood, tube connecting tools, heart probes and syringes, surgical tools, operating room devices, containers for intravenous injection, and the like.
[0029]
EXAMPLES Hereinafter, although an Example demonstrates this invention still in detail, this invention is not limited to a following example, unless the summary is exceeded.
【Example】
[Examples 1-5, Comparative Examples 1-3]
100 parts by weight of a polycarbonate resin (Iupilon S-2000, manufactured by Mitsubishi Engineering Plastics Co., Ltd., viscosity average molecular weight 25,000) and a compound having an oxymethylene unit described in Table 1, a compound having a substituted oxymethylene unit or A substituted cyclic ether compound and an aromatic compound having an oxy group or a carbonyl group are mixed by a tumbler at the ratio shown in Table 1, and extruded at a barrel temperature of 270 ° C. using a φ40 mm uniaxial vent type extruder. Pellets were obtained.
The pellets were dried at 120 ° C. for 5 hours or longer in a hot air dryer, and then a 50 mmφ × 3 mm thickness test piece was injection molded at a resin temperature of 270 ° C. and a mold temperature of 80 ° C.
Using this molded piece, cobalt 60γ rays were irradiated with 25 kilogray (kGy), and the yellowness before and after irradiation was measured with a color difference meter SM-3-CH manufactured by Suga Test Instruments Co., Ltd. according to JIS K7103. The degree of change (ΔYI) was determined. The results are shown in Table-1.
[0030]
[Table 1]

[0031]
【The invention's effect】
The composition of the present invention has little deterioration in physical properties and little change in color tone due to ionizing radiation irradiated for sterilization. Therefore, it is useful for applications such as medical products, medical devices, and members of medical devices that are sterilized by ionizing radiation irradiation.

Claims (2)

100 to 100 parts by weight of a polycarbonate resin, 0.01 to 5 parts by weight of a compound having an oxymethylene unit, a compound having a substituted oxymethylene unit or a substituted cyclic ether compound, and an aromatic compound having an oxy group or a carbonyl group 0.01 to 5 Ri Na by blending parts by weight, the compound having the compound or substituted oxymethylene units having oxymethylene units, a compound represented by the following general formula (1)

(Wherein R ¹ And R ² Are H, C1-30 alkyl group, cycloalkyl group, alkenyl group, aryl group, arylalkyl group, arylalkenyl group, hydroxy group, alkoxy group, acyl group or acyloxy group, respectively, aryl group, arylalkyl group The nucleus of the group and the arylalkenyl group can have a C1-10 alkyl group or a halogen group as a substituent, and m is an integer of 3 or more. ) ,
The substituted cyclic ether compound is a compound represented by the following general formula (3)

(Wherein R ⁷ And R ⁸ Are H, C1-30 alkyl group, cycloalkyl group, alkenyl group, aryl group, arylalkyl group, arylalkenyl group, hydroxy group, alkoxy group, acyl group or acyloxy group, respectively, aryl group, arylalkyl group And the nucleus of the arylalkenyl group may have a C1-10 alkyl group or a halogen group as a substituent, and R ⁹ And R ¹⁰ are H, a C1-30 alkyl group, a cycloalkyl group, an alkenyl group, an aryl group, an arylalkyl group, an arylalkenyl group, or an acyl group, respectively, of the aryl group, arylalkyl group, and arylalkenyl group. The nucleus may have a C1-10 alkyl group or a halogen group as a substituent, and n is an integer of 1 or more. )
Polycarbonate resin composition characterized by. The polycarbonate resin composition according to claim 1, wherein the aromatic compound having an oxy group or a carbonyl group is a compound represented by the following general formula (4) or (5).

Wherein R ¹¹ , R ¹³ and R ¹⁵ are each a C1-10 alkyl group, alkoxy group, alkoxyalkyl group, arylalkoxyalkyl group, —CH ₂ An OH group or a halogen group, and R ¹⁴ is a C1-15 alkylene group, alkenylene group, arylene group, alkylenedioxy group or arylene alkyleneoxy group, and the nucleus of the arylene group and arylene alkyleneoxy group is As a substituent, it can have a C1-10 alkyl group or a halogen group, and X ¹ , X ² And X ³ Are —O—, —CHR ¹⁶ —O—, —CO—, —CHR ¹⁷ —CO—, —CO—CO— or —CO—C (OR ¹⁸ ) _{2, respectively.} R ¹² , R ¹⁶ , R ¹⁷ and R ¹⁸ are H, C1-30 alkyl group, cycloalkyl group, alkenyl group, aryl group, arylalkyl group, arylalkenyl group, hydroxy group, respectively. , An alkoxy group, an arylalkoxy group, an arylalkylalkoxy group, an acyl group or an arylacyl group, and the nucleus of the aryl group, arylalkyl group, arylalkenyl group, arylalkoxy group, arylalkylalkoxy group and arylacyl group is substituted. The group may have a C1-10 alkyl group or a halogen group, and when there are two or more substituents having R ^{12 in the} same nucleus, the substituents are bonded to each R ^12. It may be connected by covalent bond, and h, j and k are each an integer of 0 to 5 Ri, i is an integer from 1 to 6, the sum of h and i is 1-6. )