JPH0920744A - Prevention of discoloration of organic isocyanate compound - Google Patents
Prevention of discoloration of organic isocyanate compoundInfo
- Publication number
- JPH0920744A JPH0920744A JP16876295A JP16876295A JPH0920744A JP H0920744 A JPH0920744 A JP H0920744A JP 16876295 A JP16876295 A JP 16876295A JP 16876295 A JP16876295 A JP 16876295A JP H0920744 A JPH0920744 A JP H0920744A
- Authority
- JP
- Japan
- Prior art keywords
- isocyanate compound
- group
- component
- isocyanate
- organic isocyanate
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Pending
Links
Landscapes
- Organic Low-Molecular-Weight Compounds And Preparation Thereof (AREA)
- Anti-Oxidant Or Stabilizer Compositions (AREA)
Abstract
Description
【０００１】[0001]
【産業上の利用分野】本発明はイソシアナート化合物
の、空気、光、熱などに対する安定性を改良する方法に
関する。トリレンジイソシアナート、ジフェニルメタン
ジイソシアナート、ヘキサメチレンジイソシアナートな
どのイソシアナート化合物は、極めて反応性に富み、活
性水素を有する多くのポリオール類と反応させて弾性
体、発泡体、接着剤、塗料、繊維等各方面の用途に使用
されている。FIELD OF THE INVENTION The present invention relates to a method for improving the stability of an isocyanate compound against air, light, heat and the like. Isocyanate compounds such as tolylene diisocyanate, diphenylmethane diisocyanate, and hexamethylene diisocyanate are extremely reactive and react with many polyols having active hydrogen to produce elastic bodies, foams, adhesives, paints. It is used for various purposes such as textiles.
【０００２】[0002]
【従来の技術】イソシアナート化合物は着色しやすい物
質であり、精製直後は殆ど無色であるが、貯蔵中に空気
や光に触れたり、加熱されたりすると、微量の含有不純
物やイソシアナート基の経時酸化などにより着色を呈す
るようになる。特に塗料用に使用される場合は問題とな
り、イソシアナート化合物を塗料に用いる際は通常、イ
ソシアナート化合物をアダクト化、あるいはビウレット
化したいわゆる変性イソシアナートとして用いられてい
るが、これらの化合物は保存中に着色を呈するだけでは
なく、変性反応時の加熱により着色した製品となり、著
しく商品価値を損なう。また、他の用途にもイソシアナ
ート化合物が着色することにより製品の色相が変化し、
問題を生じていることから解決が望まれていた。2. Description of the Related Art Isocyanate compounds are substances that are easily colored, and are almost colorless immediately after purification, but if they are exposed to air or light or are heated during storage, trace amounts of impurities and isocyanate groups contained therein will change over time. It becomes colored due to oxidation. It becomes a problem especially when used for paints, and when using isocyanate compounds for paints, it is usually used as a so-called modified isocyanate in which the isocyanate compound is adducted or biuretized, but these compounds are stored. Not only does it exhibit coloring inside, but it also becomes a colored product due to heating during the denaturation reaction, significantly impairing the commercial value. In addition, the hue of the product changes due to the coloring of the isocyanate compound for other purposes,
A solution was desired because it caused a problem.
【０００３】[0003]
【発明が解決しようとする課題】イソシアナート化合物
の着色防止法は、精密な条件下での精留等の精製方法だ
けでは充分ではないので貯蔵中の着色防止のために通
常、２，６−ジ−ｔｅｒｔ−ブチル−４−メチルフェノ
ール（以下ＢＨＴと称する）などのような一般に酸化防
止剤として公知の化合物や、２−（３，５−ジ−ｔｅｒ
ｔ−アミル−２−ヒドロキシフェニル）ベンゾトリアゾ
ール（以後チヌビンと称する）のような一般に紫外線防
止剤として公知の化合物を添加してイソシアナート化合
物の安定化が行われている。 また、これらの安定剤の
ほかに、イソシアナート化合物の着色防止方法として米
国特許第２９５７９０３号にはトリフェニルフォスファ
イト（以下ＴＰＰと称する）などのトリアリル亜燐酸エ
ステルの添加が、また、特開昭４９−７５５０５号には
エチルトリフォスフェートの添加が、また、特開昭５９
−９８０５０号、特開平５−６５２６４号には有機亜燐
酸エステル類の添加が、それぞれ記載されている。As a method for preventing the coloration of the isocyanate compound, a purification method such as rectification under precise conditions is not sufficient. Therefore, usually 2,6- Compounds generally known as antioxidants such as di-tert-butyl-4-methylphenol (hereinafter referred to as BHT) and 2- (3,5-di-ter).
Stabilization of the isocyanate compound is carried out by adding a compound generally known as an ultraviolet ray inhibitor such as t-amyl-2-hydroxyphenyl) benzotriazole (hereinafter referred to as tinuvin). In addition to these stabilizers, the addition of triallyl phosphite such as triphenyl phosphite (hereinafter referred to as TPP) to U.S. Pat. No. 2,957,903 is a method for preventing coloration of isocyanate compounds. No. 49-75505, the addition of ethyl triphosphate is also disclosed in
-98050 and JP-A-5-65264 describe addition of organic phosphites, respectively.
【０００４】しかしながら、本発明者らの追試によれ
ば、これら公知の化合物の添加によるイソシアナート化
合物の着色防止は必ずしも充分とは言えない。また、本
発明において使用する片ヒンダードフェノールは、合成
ゴム、ポリオレフィン、ＡＢＳ樹脂、ＡＳ樹脂、ウレタ
ン樹脂などの合成樹脂用途では公知の化合物であるが、
イソシアナート化合物の着色防止については知られてお
らず、さらに、本発明者らの検討によれば片ヒンダード
フェノールは単独では着色防止効果は充分なものとはい
えない。However, according to the additional tests of the present inventors, it cannot be said that the prevention of coloration of the isocyanate compound by the addition of these known compounds is necessarily sufficient. Further, the one-sided hindered phenol used in the present invention is a known compound for synthetic resin applications such as synthetic rubber, polyolefin, ABS resin, AS resin and urethane resin.
The prevention of coloration of the isocyanate compound is not known, and further, according to the studies by the present inventors, the hindered phenol alone cannot be said to have a sufficient coloration prevention effect.
【０００５】[0005]
【課題を解決するための手段】本発明者らはこの問題を
解決するために、種々の化合物についてその添加の効果
を詳細にスクリーニングした結果、片ヒンダードフェノ
ールのある種の化合物は、単独では公知の着色防止効果
しかないが、これを特定の安定剤と組み合わせて使用し
た場合、その相乗効果が極端に大きくなることを見出
し、この知見に基づいて本発明は完成されたものであ
る。In order to solve this problem, the present inventors have made a detailed screening of the effects of addition of various compounds, and as a result, certain compounds of mono-hindered phenol were Although it has only a known anti-coloring effect, it was found that the synergistic effect becomes extremely large when it is used in combination with a specific stabilizer, and the present invention has been completed based on this finding.
【０００６】すなわち、本発明はイソシアナート化合物
の着色防止方法として３成分系よりなる新規の着色防止
剤を提供するものであり、次の（１）及び（２）の通り
である。 （１）イソシアナート化合物に一般式（Ｉ）That is, the present invention provides a novel three-component color preventive agent as a method for preventing coloration of an isocyanate compound, as shown in the following (1) and (2). (1) General formula (I) for the isocyanate compound
【化２】 〔式中、Ｒ1、Ｒ2は、同一または相異なる、炭素数１〜
１０の直鎖状又は枝別れのある飽和炭化水素基を、Ｒ3
は炭素数１〜１０の直鎖状もしくは枝別れのある炭化水
素基、エーテル基又はチオエーテル基を示す。〕で表わ
される片ヒンダードフェノール類、２，６−ジ−ｔｅｒ
ｔ−ブチル−４−メチルフェノールおよびトリフェニル
フォスファイトを添加することを特徴とするイソシアナ
ート化合物の着色防止方法。 （２）一般式（Ｉ）中、Ｒ1がメチル基、Ｒ2がｔｅｒｔ
−ブチル基、Ｒ3がブチリデン基である、即ち一般式
（Ｉ）で表わされる片ヒンダードフェノールが４，４’
−ブチリデンビス（３−メチル−６−ｔｅｒｔ−ブチル
フェノール）である（１）記載のイソシアナート化合物
の着色防止方法。Embedded image [In the formula, R 1 and R 2 are the same or different and have 1 to 1 carbon atoms.
10 straight-chain or branched saturated hydrocarbon groups can be used as R 3
Represents a linear or branched hydrocarbon group having 1 to 10 carbon atoms, an ether group or a thioether group. ] Hindered phenols represented by the formula 2,6-di-ter
A method for preventing coloration of an isocyanate compound, which comprises adding t-butyl-4-methylphenol and triphenylphosphite. (2) In the general formula (I), R 1 is a methyl group and R 2 is tert.
A butyl group and R 3 is a butylidene group, that is, the one-hindered phenol represented by the general formula (I) is 4,4 ′.
-A method for preventing coloration of an isocyanate compound according to (1), which is butylidene bis (3-methyl-6-tert-butylphenol).
【０００７】本発明方法に使用する片ヒンダードフェノ
ールは、合成ゴム、合成樹脂などの酸化防止剤として使
用されている公知化合物であり、例えば、４，４’−ブ
チリデンビス（３−メチル−６−ｔｅｒｔ−ブチルフェ
ノール）、１，１，３−トリス（２−メチル−４−ヒド
ロキシ−５−ｔｅｒｔ−ブチルフェニル）ブタン、４，
４’−チオビス（３−メチル−６−ｔｅｒｔ−ブチルフ
ェノール）などが挙げられる。 本発明方法において
は、イソシアナート化合物の種類、および組成により異
なるが、片ヒンダードフェノールの添加量はイソシアナ
ート化合物１００重量部あたり、通常、０．００５〜
１．０重量部程度、好ましくは、０．０１〜０．０５重
量部を添加する。ＢＨＴの添加量はイソシアナート化合
物１００重量部あたり通常、０．００５〜１．０重量部
程度、好ましくは、０．０１〜０．０５重量部を添加す
る。ＴＰＰの添加量はイソシアナート化合物１００重量
部あたり通常、０．００５〜１．０重量部程度、好まし
くは、０．０１〜０．０５重量部を添加する。The one-sided hindered phenol used in the method of the present invention is a known compound used as an antioxidant for synthetic rubbers, synthetic resins and the like. For example, 4,4'-butylidenebis (3-methyl-6-). tert-butylphenol), 1,1,3-tris (2-methyl-4-hydroxy-5-tert-butylphenyl) butane, 4,
4'-thiobis (3-methyl-6-tert-butylphenol) and the like can be mentioned. In the method of the present invention, the addition amount of the one-hindered phenol is usually 0.005 to 100 parts by weight of the isocyanate compound, although it depends on the type and composition of the isocyanate compound.
About 1.0 part by weight, preferably 0.01 to 0.05 part by weight is added. The amount of BHT added is usually about 0.005 to 1.0 part by weight, preferably 0.01 to 0.05 part by weight, per 100 parts by weight of the isocyanate compound. The amount of TPP added is usually about 0.005 to 1.0 part by weight, preferably 0.01 to 0.05 part by weight, per 100 parts by weight of the isocyanate compound.
【０００８】添加方法としては、３成分化合物を別々に
直接添加してもよく、また、あらかじめ３成分化合物を
混合しておき、その後添加してもよい。これらの３成分
化合物は添加後撹拌するだけで常温でも均一に溶解混合
されて充分効果が発揮される。また、あらかじめ少量の
イソシアナート化合物に溶解して添加剤濃度の高いイソ
シアナート化合物を作り、その後、大量のイソシアナー
ト化合物に添加して３成分添加剤の濃度を調整するよう
に添加してもよい。As a method of addition, the three-component compounds may be directly added separately, or the three-component compounds may be mixed in advance and then added. These three-component compounds are uniformly dissolved and mixed even at room temperature by adding and stirring, and the effects are sufficiently exhibited. Alternatively, the compound may be dissolved in a small amount of an isocyanate compound in advance to form an isocyanate compound having a high additive concentration, and then added to a large amount of the isocyanate compound so as to adjust the concentration of the three-component additive. .
【０００９】本発明に適用できるイソシアナート化合物
は、トリレンジイソシアナート、ジフェニルメタンジイ
ソシアナート、ナフチレンジイソシアナートなどの芳香
族イソシアナート、ヘキサメチレンジイソシアナート、
ブチルジイソシアナート、などの脂肪族イソシアナー
ト、ジシクロヘキシルメタンジイソシアナートなどの脂
環式イソシアナート、およびこれらの混合物などのほか
これらのビウレット変性イソシアナート、ウレタン変性
イソシアナート、カルボジイミド変性イソシアナートな
どの変性イソシアナート化合物にも適用できる。Isocyanate compounds applicable to the present invention include aromatic diisocyanates such as tolylene diisocyanate, diphenylmethane diisocyanate and naphthylene diisocyanate, hexamethylene diisocyanate,
Butyl diisocyanate, aliphatic isocyanate such as dicyclohexylmethane diisocyanate, alicyclic isocyanate such as dicyclohexylmethane diisocyanate, and mixtures thereof, as well as biuret modified isocyanate, urethane modified isocyanate, carbodiimide modified isocyanate It can also be applied to modified isocyanate compounds.
【００１０】[0010]
【実施例】以下、実施例により本発明の方法をさらに詳
細に示すが、これらの実施例は本発明を限定するもので
はない。例中特に断らない限り総ての部、および比率は
重量基準による。The method of the present invention will be described in more detail with reference to the following examples, but these examples do not limit the present invention. Unless otherwise specified, all parts and ratios are by weight.
【００１１】実施例１ 精留塔より得られた純度９９．９％の精トリレンジイソ
シアナート（色相ＡＰＨＡ ５）に表１に示す添加剤を
それぞれ添加して撹拌混合後、その３００ｇを透明ガラ
ス製の容器にそれぞれを入れて窒素シール後、密閉し、
室内で曝光放置して経時変化による着色試験を行った。
その結果を表１に示す。Example 1 To the purified tolylene diisocyanate (hue APHA 5) having a purity of 99.9% obtained from a rectification column, the additives shown in Table 1 were added, and the mixture was stirred and mixed. Put each in a container made of nitrogen, seal with nitrogen, and then seal,
The specimen was left exposed to light in a room and a coloring test was performed by aging.
Table 1 shows the results.
【００１２】実施例２ 精留塔より得られた純度９９．９％の精ジフェニルメタ
ンジイソシアナート（色相ＡＰＨＡ ５）に表２に示す
添加剤をそれぞれ添加して撹拌混合後、その３００ｇを
透明ガラス製の容器にそれぞれを入れて窒素シール後、
密閉し、室内で曝光放置して経時変化による着色試験を
行った。その結果を表２に示す。Example 2 Additives shown in Table 2 were added to purified diphenylmethane diisocyanate (hue APHA 5) having a purity of 99.9% obtained from a rectification column, and the mixture was stirred and mixed, and 300 g of the transparent glass was added. After putting each in a container made of nitrogen and sealing with nitrogen,
It was hermetically sealed and left to stand in a room for light, and a coloring test was performed by aging. Table 2 shows the results.
【００１３】実施例３ 純度９９．９％、加水分解性塩素０．００４％を含有す
る２，４−トリレンジイソシアナート２００ｇを酢酸エ
チル１６７ｇに加え、６０℃でトリメチロールプロパン
５１ｇを加えて、４時間撹拌し、ＮＣＯ％が１２．２％
のプレポリマ溶液を合成した。このプレポリマー溶液
（色相ＡＰＨＡ １０）に、表３に示す添加剤をそれぞ
れ加え、実施例１と同様にしてその着色度を調べた。結
果を表３に示す。Example 3 200 g of 2,4-tolylene diisocyanate containing 99.9% of purity and 0.004% of hydrolyzable chlorine was added to 167 g of ethyl acetate, and 51 g of trimethylolpropane was added at 60 ° C. Stir for 4 hours, NCO% 12.2%
Was prepared. The additives shown in Table 3 were added to this prepolymer solution (hue APHA 10), and the degree of coloring was examined in the same manner as in Example 1. The results are shown in Table 3.
【００１４】実施例４ ＢＨＴ、トリフェニルフォスファイトおよび４，４’−
ブチリデンビス（３−メチル−６−ｔｅｒｔ−ブチルフ
ェノール）（住友化学（株）製 商品名、スミライザー
ＢＢＭ）のそれぞれ等量をあらかじめ混合しておき、こ
れを３００ｐｐｍ含有するようにヘキサメチレンジイソ
シアナートに添加撹拌して、その３００ｇを１４０℃に
加熱し、水蒸気５．０ｇを４時間で吸い込み、ヘキサメ
チレンジイソシアナートのビウレット化反応を行った。
反応終了後スミス蒸発器で未反応ヘキサメチレンジイソ
シアナートを除き、反応物をキシレンとセルソルブアセ
テートの１：１比率の溶媒で希釈して７５％溶液とし
た。このものは微黄色透明で色相はＡＰＨＡ４０であっ
た。なお、ヘキサメチレンイソシアナートに無添加でビ
ウレット化反応をして同じく処理、調製して得られた７
５％溶液の色相はＡＰＨＡ２００であった。Example 4 BHT, triphenyl phosphite and 4,4'-
Equal amounts of butylidene bis (3-methyl-6-tert-butylphenol) (Sumitomo Chemical Co., Ltd. trade name, Sumilizer BBM) were mixed in advance and added to hexamethylene diisocyanate to contain 300 ppm. After stirring, 300 g of the mixture was heated to 140 ° C., 5.0 g of steam was sucked in for 4 hours, and a biuretization reaction of hexamethylene diisocyanate was performed.
After completion of the reaction, unreacted hexamethylene diisocyanate was removed by a Smith evaporator, and the reaction product was diluted with a solvent of xylene and cellosolve acetate in a ratio of 1: 1 to prepare a 75% solution. This product was slightly yellow and transparent and had a hue of APHA40. It should be noted that it was obtained by subjecting hexamethylene isocyanate to a biuretization reaction without addition and treating and preparing it in the same manner.
The hue of the 5% solution was APHA200.
【００１５】[0015]
【表１】 [Table 1]
【００１６】[0016]
【表２】 [Table 2]
【００１７】[0017]
【表３】 [Table 3]
【００１８】[0018]
【発明の効果】本発明方法に従えば、イソシアナートの
着色を効果的に防止することが可能になるため、商品価
値の高いイソシアナート化合物を製造する方法として好
適である。EFFECTS OF THE INVENTION According to the method of the present invention, it is possible to effectively prevent the coloration of the isocyanate, which is suitable as a method for producing an isocyanate compound having a high commercial value.
───────────────────────────────────────────────────── フロントページの続き (72)発明者 谷口 敏幸 福岡県大牟田市浅牟田町30番地 三井東圧 化学株式会社内 (72)発明者 高柳 弘 神奈川県横浜市栄区笠間町1190番地 三井 東圧化学株式会社内 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Toshiyuki Taniguchi 30 Asamu-cho, Omuta-shi, Fukuoka Mitsui Toatsu Kagaku Co., Ltd. (72) Inventor Hiroshi Takayanagi 1190 Kasama-cho, Sakae-ku, Yokohama, Kanagawa Within the corporation
Claims (2)
１０の直鎖状又は枝別れのある飽和炭化水素基を、Ｒ3
は炭素数１〜１０の直鎖状もしくは枝別れのある炭化水
素基、エーテル基又はチオエーテル基を示す。〕で表わ
される片ヒンダードフェノール類、２，６−ジ−ｔｅｒ
ｔ−ブチル−４−メチルフェノールおよびトリフェニル
フォスファイトを添加することを特徴とするイソシアナ
ート化合物の着色防止方法。1. An isocyanate compound represented by the general formula (I): [In the formula, R 1 and R 2 are the same or different and have 1 to 1 carbon atoms.
10 straight-chain or branched saturated hydrocarbon groups can be used as R 3
Represents a linear or branched hydrocarbon group having 1 to 10 carbon atoms, an ether group or a thioether group. ] Hindered phenols represented by the formula 2,6-di-ter
A method for preventing coloration of an isocyanate compound, which comprises adding t-butyl-4-methylphenol and triphenylphosphite.
ｅｒｔ−ブチル基、Ｒ3がブチリデン基である、即ち一
般式（Ｉ）で表わされる片ヒンダードフェノールが４，
４’−ブチリデンビス（３−メチル−６−ｔｅｒｔ−ブ
チルフェノール）である請求項１記載のイソシアナート
化合物の着色防止方法。2. In the general formula (I), R 1 is a methyl group and R 2 is t.
an ert-butyl group and R 3 is a butylidene group, that is, the one-hindered phenol represented by the general formula (I) is 4,
The method for preventing coloration of an isocyanate compound according to claim 1, which is 4'-butylidene bis (3-methyl-6-tert-butylphenol).
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP16876295A JPH0920744A (en) | 1995-07-04 | 1995-07-04 | Prevention of discoloration of organic isocyanate compound |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP16876295A JPH0920744A (en) | 1995-07-04 | 1995-07-04 | Prevention of discoloration of organic isocyanate compound |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| JPH0920744A true JPH0920744A (en) | 1997-01-21 |
Family
ID=15873978
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP16876295A Pending JPH0920744A (en) | 1995-07-04 | 1995-07-04 | Prevention of discoloration of organic isocyanate compound |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPH0920744A (en) |
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2000290243A (en) * | 1999-03-30 | 2000-10-17 | Bayer Ag | Reduction of chlorine content in low molecular weight isocyanate |
| JP2005053870A (en) * | 2003-08-07 | 2005-03-03 | Nisshinbo Ind Inc | Carbodiimide composition inhibited from yellowing, hydrolysis stabilizer and thermoplastic resin composition |
| JP2005082642A (en) * | 2003-09-05 | 2005-03-31 | Nisshinbo Ind Inc | Hydrolysis resistance stabilizer for ester group-bearing resin and thermoplastic resin composition |
| JP2005298365A (en) * | 2004-04-07 | 2005-10-27 | Mitsui Takeda Chemicals Inc | Organic polyisocyanate composition |
-
1995
- 1995-07-04 JP JP16876295A patent/JPH0920744A/en active Pending
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2000290243A (en) * | 1999-03-30 | 2000-10-17 | Bayer Ag | Reduction of chlorine content in low molecular weight isocyanate |
| JP2005053870A (en) * | 2003-08-07 | 2005-03-03 | Nisshinbo Ind Inc | Carbodiimide composition inhibited from yellowing, hydrolysis stabilizer and thermoplastic resin composition |
| JP2005082642A (en) * | 2003-09-05 | 2005-03-31 | Nisshinbo Ind Inc | Hydrolysis resistance stabilizer for ester group-bearing resin and thermoplastic resin composition |
| JP2005298365A (en) * | 2004-04-07 | 2005-10-27 | Mitsui Takeda Chemicals Inc | Organic polyisocyanate composition |
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