JP2008115325A - Polyol composition and polyurethane foam - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a polyol composition which can improve scorch resistance while preventing discoloration to pink and a polyurethane foam using the polyol composition. <P>SOLUTION: A polyol composition which has a hydroxyl value of 5 to 1,000 KOH mg/g and comprises a polyol having an average number of functional groups of 1.5 to 8.0, an antioxidant having a plurality of metilox skeletons, an antioxidant having one metilox skeleton, and an amine based antioxidant is prepared, and the polyol composition and a polyisocyanate are reacted and foamed in the presence of a blowing agent to obtain the polyurethane foam. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a polyol composition and a polyurethane foam, and more particularly to a polyol composition and a polyurethane foam in which the polyol composition is used.

  Polyurethane foams such as flexible polyurethane foams are produced by reacting and foaming polyols and polyisocyanates in the presence of a blowing agent.

  The polyol used for the production of the polyurethane foam may be prepared and used as a premix in which various additives such as a foaming agent, a catalyst and a foam stabilizer are blended with the polyol.

Polyurethane foams, especially flexible polyurethane foams, are prone to scorch (burning, i.e. yellowing). To prevent such scorch, polyols or premixes usually contain hindered phenols as additives. An antioxidant such as a system antioxidant is blended (see, for example, Patent Document 1).
JP 2005-206710 A

  However, when an antioxidant having a methylol skeleton is used as a hindered phenol-based antioxidant, the scorch resistance can be remarkably improved, while the obtained polyurethane foam turns pink. There is.

  In particular, when a high level of scorch resistance is required, an amine-based antioxidant may be used in combination with an antioxidant having a methylolx skeleton as an antioxidant. Become prominent.

  An object of the present invention is to provide a polyol composition capable of improving the scorch resistance while preventing the color from changing to pink, and a polyurethane foam using the polyol composition.

  In order to achieve the above object, the polyol composition of the present invention has a hydroxyl value of 5 to 1000 KOHmg / g, an average functional group number of 1.5 to 8.0, and an antioxidant having a plurality of methylox skeletons. And an antioxidant having one Methylox skeleton.

  In addition, it is preferable that the polyol composition of the present invention further contains an amine-based antioxidant.

  In the polyol composition of the present invention, the total weight ratio of the antioxidant having a plurality of methylox skeletons, the antioxidant having one methylox skeleton, and the amine-based antioxidant is 10 to 10% with respect to the polyol composition. It is suitable that it is 20000 ppm.

  In the polyol composition of the present invention, the weight ratio of the antioxidant having a plurality of methylox skeletons and the antioxidant having one methylox skeleton is 100 parts by weight of the antioxidant having one methylox skeleton. It is preferable that the antioxidant having a plurality of methylox skeletons is 30 to 300 parts by weight.

  The polyurethane foam of the present invention is characterized by being obtained by reacting and foaming the above-described polyol composition and polyisocyanate in the presence of a foaming agent.

  The polyurethane foam of the present invention is preferably a flexible polyurethane foam.

  When a polyurethane foam is produced using the polyol composition of the present invention, the scorch resistance can be remarkably improved while preventing discoloration to pink. Therefore, the quality of the polyurethane foam can be improved.

  The polyol composition of the present invention contains at least a polyol, an antioxidant having a plurality of methylox skeletons, and an antioxidant having one methylox skeleton.

  In the present invention, the polyol is a compound having two or more hydroxyl groups in the molecule and is not particularly limited. For example, the polyol has a number average molecular weight of 200 to 20000, preferably 300 to 10,000, and is used as a polyurethane raw material. A polyol is mentioned. Examples of the macropolyol include polyether polyol, polyester polyol, polyether polyester polyol, and polyester polyurethane polyol. For the production of polyurethane foams, preferably polyether polyols are used.

  The polyether polyol can be obtained, for example, by addition polymerization of alkylene oxide using water, alcohols, amines, ammonia or the like as an initiator.

  Examples of alcohols as initiators include monovalent aliphatic alcohols such as methanol and ethanol, divalent aliphatic alcohols such as ethylene glycol and propylene glycol, and trivalents such as glycerin and trimethylolpropane. Monovalent or polyvalent (eg, tetravalent aliphatic alcohols such as pentaerythritol, hexavalent aliphatic alcohols such as sorbitol, octavalent aliphatic alcohols such as sucrose, etc. (Divalent to octavalent) aliphatic alcohols.

  Examples of amines as initiators include monovalent aliphatic amines such as dimethylamine and diethylamine, for example, divalent aliphatic amines such as methylamine and ethylamine, such as monoethanolamine, diethanolamine, and triamine. Trivalent aliphatic amines such as ethanolamine, for example, tetravalent aliphatic amines such as ethylenediamine, monovalent or polyvalent aliphatic amines such as pentavalent aliphatic amines such as diethylenetriamine, or And aromatic amines such as toluylenediamine and the like.

  When producing a flexible polyurethane foam, propylene glycol, glycerin, trimethylolpropane or the like is preferably used as an initiator. Moreover, when manufacturing a rigid polyurethane foam, Preferably, a trimethylol propane, sucrose, ethylenediamine, toluylenediamine etc. are used as an initiator.

  Examples of the alkylene oxide include ethylene oxide, propylene oxide, 1,2-, 1,3-, 1,4- and 2,3-butylene oxide and combinations of two or more thereof. Among these, Preferably, a propylene oxide and / or ethylene oxide are mentioned. When these are used in combination, any addition form of block polymerization and random polymerization can be selected as appropriate.

  The polyol obtained by the above addition polymerization has a hydroxyl value (OH value) of, for example, 5 to 1000 KOHmg / g, preferably 10 to 800 KOHmg / g, and an average functional group number of 1.5 to 8. 0, preferably 2.5 to 6.0.

  More specifically, when a flexible polyurethane foam is produced, the polyol has a hydroxyl value (OH value) of, for example, 5 to 300 KOHmg / g, preferably 10 to 200 KOHmg / g, and the average number of functional groups. Is 1.5 to 8.0, preferably 2.0 to 6.0.

  When a rigid polyurethane foam is produced, the polyol has a hydroxyl value (OH value) of, for example, 100 to 1000 KOHmg / g, preferably 200 to 800 KOHmg / g, and an average functional group number of 1.5. It is -8.0, Preferably, it is 2.5-7.0.

  In addition, a plurality of polyols having different types of initiator, hydroxyl value, average number of functional groups, alkylene oxide types, or addition types can be used in combination as appropriate depending on the purpose and application.

  For example, when a flexible polyurethane foam is produced, the polyol can be used in combination with a plurality of polyols having a hydroxyl value of 30 to 70 KOHmg / g and an average functional group number of 2.0 to 4.0.

  For example, when a rigid polyurethane foam is produced, the polyol has a hydroxyl value of 200 to 600 KOH mg / g, an average functional group number of 3.0 to 5.0, a polyol containing an aromatic amine as an initiator, and a hydroxyl group. A polyol containing no aromatic amines can be used in combination as an initiator having a value of 200 to 600 KOH mg / g and an average functional group number of 3.0 to 5.0.

  In the present invention, the antioxidant having a methylolic skeleton is a compound having a methylolic skeleton represented by the following formula (1).

本発明において、メチロックス骨格を有する酸化防止剤には、メチロックス骨格を複数有する酸化防止剤と、メチロックス骨格を１つ有する酸化防止剤とが含まれる。

In the present invention, the antioxidant having a methylolic skeleton includes an antioxidant having a plurality of methylolic skeletons and an antioxidant having one methylolic skeleton.

  The antioxidant having a plurality of methylox skeletons is a compound having two or more, for example, 2 to 6, preferably 2 to 4, methylo skeletons represented by the above formula (1). Examples of such a compound having a plurality of methylox skeletons include compounds corresponding to a structure obtained by dehydration condensation of a polyhydric alcohol and methyloxic acid.

  More specifically, compounds having two methylolx skeletons are, for example, ethylene glycol, propylene glycol, 1,6-hexanediol, neopentyl glycol, diethylene glycol, triethylene glycol, dipropylene glycol, cyclohexane dimethanol, bisphenol A. And a structure corresponding to a structure obtained by dehydrating condensation of a dihydric alcohol such as hydrogenated bisphenol A and a mole number of methylolic acid corresponding to the number of hydroxyl groups of the dihydric alcohol.

  Examples of the compound having three methylolx skeletons include glycerin, 2-methyl-2-hydroxymethyl-1,3-propanediol, 2,4-dihydroxy-3-hydroxymethylpentane, and 1,2,6-hexane. Corresponding to a structure in which a trihydric alcohol such as triol, trimethylolpropane, 2,2-bis (hydroxymethyl) -3-butanol and the number of moles of methyloxic acid corresponding to the number of hydroxyl groups of the trihydric alcohol are dehydrated and condensed. Is mentioned.

  Examples of the compound having four methylolx skeletons include compounds corresponding to a structure in which a tetrahydric alcohol such as pentaerythritol and a number of moles of methyloxic acid corresponding to the number of hydroxyl groups of the tetrahydric alcohol are dehydrated and condensed.

  In addition, examples of the compound having six methylolx skeletons include compounds corresponding to a structure obtained by dehydration condensation of a hexavalent alcohol such as sorbitol and a molar number of methylolic acid corresponding to the number of hydroxyl groups of the hexavalent alcohol.

  One kind of these antioxidants having a plurality of methylox skeletons may be used alone, or two or more kinds thereof may be used in combination.

  Preferred examples of the antioxidant having a plurality of methylox skeletons include an antioxidant having four methylox skeletons represented by the following formula (2).

上記式（２）で示されるメチロックス骨格を４つ有する酸化防止剤は、例えば、イルガノックス（Ｉｒｇａｎｏｘ）−１０１０（チバ・スペシャルティ・ケミカルズ製）として市販されており、そのような市販品を用いることもできる。

The antioxidant having four methylox skeletons represented by the above formula (2) is commercially available, for example, as Irganox-1010 (manufactured by Ciba Specialty Chemicals), and such a commercially available product should be used. You can also.

  The antioxidant having one methylox skeleton is a compound having one methylox skeleton represented by the above formula (1). Examples of such a compound having one methylox skeleton include those corresponding to a structure obtained by dehydration condensation of a monohydric alcohol and methyloxic acid.

  More specifically, the compound having one methylox skeleton is, for example, methanol, ethanol, propanol, butanol, hexanol, octanol, decanol, dodecanol, tetradecanol, hexadecanol, octadecanol, eicosanol, docosanol, tetra Examples thereof include those corresponding to a structure in which an aliphatic alcohol having 1 to 24 carbon atoms such as cosanol or hexacosanol and dehydration condensation of methylolic acid having the number of moles corresponding to the number of hydroxyl groups of the monohydric alcohol.

  Preferably, the compound having one methylolx skeleton is an aliphatic alcohol having 8 to 18 carbon atoms such as octanol, decanol, dodecanol, tetradecanol, hexadecanol, and octadecanol, and the number of hydroxyl groups of the monohydric alcohol. Examples thereof include a structure corresponding to a structure in which a corresponding number of moles of methyloxic acid is condensed by dehydration.

  These antioxidants having one methylox skeleton may be used alone or in combination of two or more.

  The antioxidant having one methylox skeleton is preferably an antioxidant having one methylox skeleton represented by the following formula (3) or the following formula (4).

上記式（３）で示されるメチロックス骨格を１つ有する酸化防止剤は、例えば、イルガノックス（Ｉｒｇａｎｏｘ）−１０７６（チバ・スペシャルティ・ケミカルズ製）として市販されており、そのような市販品を用いることもできる。

The antioxidant having one Methylox skeleton represented by the above formula (3) is commercially available, for example, as Irganox-1076 (manufactured by Ciba Specialty Chemicals), and such a commercially available product should be used. You can also.

  Moreover, the antioxidant having one Methylox skeleton represented by the above formula (4) is commercially available, for example, as Irganox-1135 (manufactured by Ciba Specialty Chemicals). It can also be used.

  In the present invention, an antioxidant having a plurality of methylox skeletons and an antioxidant having one methylox skeleton are used in combination. That is, when an antioxidant having a plurality of methylox skeletons is blended alone, the resulting polyurethane foam can be improved in scorch resistance, while being changed to pink. Moreover, when the antioxidant which has one Metirox skeleton is mix | blended independently, while changing the pink color of the obtained polyurethane foam can be prevented, scorch resistance falls. And by using together the antioxidant which has two or more methylox frame | skeletons, and the antioxidant which has one methylox frame | skeleton, it can aim at the improvement of scorch resistance remarkably, preventing discoloration to pink color. it can.

  The blending ratio of the antioxidant having a plurality of methylol skeletons to the polyol composition is, for example, 0.0002 parts by weight or more, preferably 0, of the antioxidant having a plurality of methylol skeletons with respect to 100 parts by weight of the polyol. 0.002 parts by weight or more, more preferably 0.02 parts by weight or more, for example, 1.5 parts by weight or less, preferably 0.75 parts by weight or less, and more preferably 0.5 parts by weight or less.

  The blending ratio of the antioxidant having one methylox skeleton with respect to the polyol composition is, for example, 0.0002 parts by weight or more, preferably, the antioxidant having one methylox skeleton with respect to 100 parts by weight of the polyol. 0.002 parts by weight or more, more preferably 0.02 parts by weight or more, for example, 1.5 parts by weight or less, preferably 0.75 parts by weight or less, more preferably 0.5 parts by weight or less. is there.

  The weight ratio of the antioxidant having a methylolx skeleton (the sum of the antioxidant having a plurality of methylolx skeletons and the antioxidant having one methylox skeleton) to the polyol composition is, for example, It is 10-20000 ppm, Preferably, it is 100-10000 ppm, More preferably, it is 1000-7000 ppm. If the weight ratio of the antioxidant having a methylol skeleton is less than 10 ppm, the polyol may undergo auto-oxidative degradation in a stored state, and abnormal phenomena such as internal cracking may occur in foaming. Further, if it is less than 1000 ppm, the scorch resistance may decrease in slab foaming or the like in which the internal heat generation temperature becomes high. Moreover, when it exceeds 20000 ppm, the speed at which the foam changes to yellow may become extremely fast.

  The weight ratio of the antioxidant having a plurality of methylox skeletons to the antioxidant having one methylox skeleton is an antioxidant having a plurality of methylox skeletons with respect to 100 parts by weight of the antioxidant having one methylox skeleton. The agent is, for example, 30 to 300 parts by weight, preferably 50 to 200 parts by weight, and more preferably 70 to 130 parts by weight. When the antioxidant having a plurality of Methylox skeletons is less than 30 parts by weight, the scorch resistance may be lowered. Moreover, when it exceeds 300 weight part, it may be unable to prevent discoloration to pink color.

  In the present invention, the polyol composition may be used in combination with an amine-based antioxidant when high scorch resistance is required. The amine-based antioxidant is not particularly limited, and examples thereof include amine-based antioxidants such as 4,4′-di-t-butyl-diphenylamine and 4,4′-di-octyl-diphenylamine.

  By adding an amine-based antioxidant, the scorch resistance can be further improved. On the other hand, when an amine-based antioxidant is blended, the color is easily changed to pink. However, as described above, the polyol composition of the present invention includes an antioxidant having a plurality of methylol skeletons and an oxidation having one methylol skeleton. Since the inhibitor is used in combination, such discoloration can be effectively prevented even if an amine-based antioxidant is added.

The blending ratio of the amine antioxidant to the polyol composition is, for example, 0.01 parts by weight or more, preferably 0.01 parts by weight or more, preferably 100 parts by weight of the polyol.
0.03 part by weight or more, more preferably 0.05 part by weight or more, for example, 0.5 part by weight or less, preferably 0.3 part by weight or less, more preferably 0.2 part by weight or less. . When the mixing ratio of the amine-based antioxidant is less than 0.01 parts by weight, the scorch resistance may not be improved. Moreover, when it exceeds 0.5 weight part, the degree which changes to yellow may be too strong.

  The weight ratio between the amine-based antioxidant and the antioxidant having a methylolic skeleton (the sum of an antioxidant having a plurality of methylolic skeletons and an antioxidant having one methylolic skeleton) is an oxidation having a methylolic skeleton. The amine antioxidant is, for example, 5 to 400 parts by weight, preferably 10 to 100 parts by weight, and more preferably 15 to 50 parts by weight with respect to 100 parts by weight of the inhibitor. If the amine-based antioxidant is less than 5 parts by weight, the scorch resistance may not be improved. Moreover, when it exceeds 400 weight part, the degree which changes to yellow may be too strong.

The weight ratio of the total amount of the antioxidant having a methylolic skeleton (the total of the antioxidant having a plurality of methylolic skeletons and the antioxidant having one methylolic skeleton) and the amine-based antioxidant is, for example, polyol For the composition, for example, 10
To 20000 ppm, preferably 100 to 10000 ppm, and more preferably 1000 to 7000 ppm. If the total weight ratio of these antioxidants is less than 1000 ppm, the scorch resistance may decrease. On the other hand, if it exceeds 20000 ppm, the speed at which the color changes to yellow may become extremely fast.

  Further, in the present invention, the polyol composition further includes, for example, a phenol-based antioxidant and an anti-benzophenone-based antioxidant excluding an antioxidant having a methylol skeleton within a range that does not inhibit the excellent effects of the present invention. Known antioxidants such as an agent, a thioether-based antioxidant, and a phosphorus-based antioxidant can be blended at an appropriate blending ratio.

  When the polyol composition of the present invention is used for the production of polyurethane foam, a premix is prepared by further blending the polyol composition of the present invention with various additives such as a foaming agent, a catalyst and a foam stabilizer. To do.

  Although it does not restrict | limit especially as a foaming agent, For example, water and / or a halogen substituted aliphatic hydrocarbon type foaming agent, for example, trichlorofluoromethane, dichlorodifluoromethane, trichloroethane, trichloroethylene, tetrachloroethylene, methylene chloride, trichlorotrifluoroethane, Examples include dibromotetrafluoroethane and carbon tetrachloride. These foaming agents can be used alone or in combination of two or more.

  The blending ratio of the foaming agent is, for example, 0.1 to 30.0 parts by weight, preferably 0.5 to 20.0 parts by weight with respect to 100 parts by weight of the polyol composition.

  The blending ratio of water is, for example, 0.1 to 10.0 parts by weight, preferably 0.5 to 6.0 parts by weight with respect to 100 parts by weight of the polyol composition.

  The catalyst is not particularly limited. For example, tertiary amines such as triethylamine, triethylenediamine, and N-methylmorpholine, for example, quaternary ammonium salts such as tetraethylhydroxylammonium, such as imidazole, 2-ethyl-4-methyl, and the like. Examples include amine-based catalysts such as imidazoles such as imidazole. Also, for example, organic tin compounds such as tin acetate, tin octylate, dibutyltin dilaurate and dibutyltin chloride, for example, organic lead compounds such as lead octylate and lead naphthenate, for example, organic nickel compounds such as nickel naphthenate And organometallic catalysts such as These catalysts can be used alone or in combination of two or more.

  The blending ratio of the catalyst is, for example, 0.01 to 2.0 parts by weight, preferably 0.05 to 1.0 parts by weight with respect to 100 parts by weight of the polyol composition.

  In addition, for example, a catalyst having high hydrolyzability such as an organometallic catalyst is not blended in the premix in advance, but is blended in the premix immediately before foaming.

  Although it does not restrict | limit especially as a foam stabilizer, For example, silicone type foam stabilizers, such as a siloxane-oxyalkylene block copolymer, are mentioned.

  The blending ratio of the foam stabilizer is, for example, 0.1 to 5.0 parts by weight, preferably 0.3 to 3.0 parts by weight with respect to 100 parts by weight of the polyol composition.

  In preparation of the premix, various additives such as a chain extender, a flame retardant, a colorant, a plasticizer, and an ultraviolet absorber can be blended at an appropriate blending ratio in addition to the above-described components. .

  And the polyol composition of this invention Furthermore, a premix can be prepared by mix | blending and mixing each above-described component by the above-mentioned mixture ratio.

  The polyol composition of the present invention is preferably prepared as a premix as described above and used for the production of polyurethane foam.

  In order to produce the polyurethane foam of the present invention, for example, a premix is prepared by blending the polyol composition of the present invention with a foaming agent, a catalyst and a foam stabilizer, and the premix is reacted with a polyisocyanate. And foaming with a foaming agent.

  The polyisocyanate is not particularly limited. For example, aromatic polyisocyanate such as 2,4- or 2,6-tolylene diisocyanate (TDI), diphenylmethane diisocyanate (MDI), phenylene diisocyanate (PDI), and naphthalene diisocyanate (NDI). Isocyanates, for example araliphatic polyisocyanates such as 1,3- or 1,4-xylylene diisocyanate (XDI), for example aliphatic polyisocyanates such as hexamethylene diisocyanate (HDI), for example 3-isocyanatomethyl- 3,5,5-trimethylcyclohexyl isocyanate (IPDI), 4,4′-methylenebis (cyclohexyl isocyanate) (H12MDI), 1,3- or 1,4-bis (isocyanatomethyl) cyclohexane An alicyclic polyisocyanate such as sun (H6XDI) and a carbodiimide modified product, biuret modified product, allophanate modified product, dimer, trimer or polymethylene polyphenyl polyisocyanate (crude MDI) of the above-mentioned polyisocyanate , Polymeric MDI) and the like. An aromatic polyisocyanate is preferable, and TDI is more preferable. These polyisocyanates can be used alone or in combination of two or more.

  The blending ratio of the polyisocyanate is, for example, 60 to 500, preferably 70 to 130, for example, as an isocyanate index (a ratio of an isocyanate group to an active hydrogen 100 such as a hydroxyl group in a polyol composition and water as a blowing agent). It is.

  And in order to manufacture a polyurethane foam, the premix containing the polyol composition of the present invention and a polyisocyanate are blended and foamed by a known foaming method such as a slab method, a mold method, or a spray method. Thereby, the polyurethane foam of the present invention can be obtained.

  The polyurethane foam of the present invention is not particularly limited, and is preferably a flexible foam such as a soft slab foam or a flexible mold foam, for example, a rigid foam such as a rigid slab foam or a rigid mold foam, preferably a flexible foam, more preferably Manufactured as a soft slab foam and used in various industrial applications.

  And since the polyol composition of this invention is used for the polyurethane foam of this invention, it can prevent a discoloration to pink color, and can aim at the improvement of scorch resistance notably. Therefore, the quality of the polyurethane foam can be improved.

EXAMPLES Hereinafter, although an Example and a comparative example demonstrate this invention concretely, this invention is not limited by this.
1) Preparation of premix Polypropylene glycol 79-56 (manufactured by Mitsui Chemicals Polyurethanes Co., Ltd., propylene oxide homoaddition polymer of glycerin initiator, hydroxyl value 56, average functional group number 3, number average molecular weight 3000) is shown in Table 1. Irganox 1010, Irganox 1076, Irganox 1135 and Stirrer STAR (Seiko Chemical Co., Ltd., di-t-butyl-diphenylamine) were dissolved and blended so that the weight ratio (ppm) was obtained. 8 and Comparative Examples 1-4 were prepared respectively. 100 parts by weight of each polyol composition, 4.5 parts by weight of water, 0.3 parts by weight of Dabco 33LV (manufactured by Air Products and Chemicals, triethylenediamine / dipropylene glycol (67% solution)), and L-580 ( A premix of Examples 1 to 8 and Comparative Examples 1 to 4 was prepared by blending 1.5 parts by weight of a silicone-based foam stabilizer manufactured by GE Toshiba Silicone Co., Ltd.

２）ポリウレタンフォームの製造
上記により得られた各実施例および各比較例のプレミックスを、ハンドミキサーで攪拌した後、ダブコＴ−９（エアプロダクツ アンド ケミカルズ社製、オクチル酸スズ）０．１７重量部を添加して、さらに５秒間攪拌後、イソシアネートインデックスが１１５となる割合で、ＴＤＩ−８０（トルエンジイソシアネート（２，４−異性体８０重量％、２，６−異性体２０重量％の混合物、三井化学ポリウレタン社製）を添加混合し、混合物を発泡箱に投入して、発泡させることにより、軟質スラブポリウレタンフォームを得た。

2) Manufacture of polyurethane foam The premixes of Examples and Comparative Examples obtained as described above were stirred with a hand mixer, and then DABCO T-9 (Air Products and Chemicals, tin octylate) 0.17 wt. After stirring for 5 seconds, the TDI-80 (toluene diisocyanate (80% by weight of 2,4-isomer, 20% by weight of 2,6-isomer, (Mitsui Chemical Polyurethane Co., Ltd.) was added and mixed, and the mixture was put into a foaming box and foamed to obtain a soft slab polyurethane foam.

  The soft slab polyurethane foam was foamed on the weight base and scale shown in the following 3) evaluation.

And about the obtained soft slab polyurethane foam, the pink discoloration degree and the scorch degree were evaluated by the method shown below. The results are shown in Table 1.
3) Evaluation 3-1 Pink discoloration The foam was foamed in an open box of 270 mm × 270 mm × 270 mm based on 300 g of polyol. Leave at room temperature, and after 2 days, cut out a 100 mm × 100 mm × 30 mm foam piece from the center of the polyurethane foam, place it on a petri dish (inner diameter 90 mm), and leave the foam piece with a color difference meter 3 days later. The degree of redness (a value) on the upper surface was measured.

In order to accelerate the pink discoloration of the polyurethane foam, 10 g of an amine catalyst (Niax A1, manufactured by GE Toshiba Silicones, bis (2-dimethylaminoethyl) ether / dipropylene glycol (70% solution)) was added to the petri dish. , Put in advance. In Table 1, it shows that pink discoloration degree is so large that a value is high.
3-2 Degree of scorch Foaming was performed in an open box of 200 mm x 200 mm x 200 mm based on a polyol of 120 g. Heat for the first time in a microwave oven for 5 minutes from 3 to 8 minutes after the start of premix stirring (mode: weak, strength 2), then repeat decompression and external air insertion twice in the desiccator, From 14 minutes to 15 minutes after the start of stirring, the mixture was heated in a microwave for 1 minute (mode: weak, strength 2). On the next day, the polyurethane foam was cut, and the yellowing degree (b value) was measured with a color difference meter for the most yellowed portion near the center of the foam. In Table 1, it shows that yellowing degree is so large that b value is high, ie, generation | occurrence | production of scorch (burning) is large.

  In addition, said color difference is a value and b value of a color difference (CIE1976), and the color difference value was measured by Tokyo Denshoku Co., Ltd. make, fully automatic color difference meter color ACE MODEL TC-1.

Claims (6)

  Contains a polyol having a hydroxyl value of 5 to 1000 KOHmg / g and an average functional group number of 1.5 to 8.0, an antioxidant having a plurality of methylox skeletons, and an antioxidant having one methylox skeleton. A polyol composition characterized by the above.   The polyol composition according to claim 1, further comprising an amine-based antioxidant.   The total weight ratio of the antioxidant having a plurality of methylox skeletons, the antioxidant having one methylox skeleton, and the amine-based antioxidant is 10 to 20000 ppm relative to the polyol composition, Item 3. A polyol composition according to Item 2.   An antioxidant having a plurality of methylox skeletons with respect to 100 parts by weight of an antioxidant having one methylox skeleton in a weight ratio of an antioxidant having a plurality of methylox skeletons and an antioxidant having one methylox skeleton. It is 30-300 weight part, The polyol composition in any one of Claims 1-3 characterized by the above-mentioned.   A polyurethane foam obtained by reacting and foaming the polyol composition according to any one of claims 1 to 4 and a polyisocyanate in the presence of a foaming agent.   The polyurethane foam according to claim 5, which is a flexible polyurethane foam.