JP2000109617A - Stabilized polyolefin-based resin composition - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a polyolefin-based resin compsn. which is highly stabilized to the thermal and mechanical decomposition by the shear force at the time of processing the polyolefin-based resin. SOLUTION: A polyolefin-based resin compsn. comprises a blend of a polyolefin-based resin and, based on 100 pts.wt. of the resin, 0.001-1.0 pt.wt. of (A) a tocopherol, 0.001-1.0 pt.wt. of (B) a phenol-based stabilizer with a mol.wt. of 300 or more, and 0.001-1.0 pt.wt. of (C) a phosphorus-based stabilizer. The polyolefin-based resin is pref. a polypropylene-based resin.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] The present invention relates to a stabilized polyolefin resin composition. More specifically, the present invention relates to a polyolefin resin composition highly stabilized against thermal and mechanical decomposition due to shearing during processing of the polyolefin resin.

[0002]

2. Description of the Related Art Polypropylene resins are widely used as materials for molded articles, fibers, films, sheets, etc. because of their excellent appearance, mechanical properties, suitability for packaging, and processing characteristics. However, polyolefin resin is molded at a temperature suitable for the melting temperature of the resin, specifically at a high temperature of usually 150 to 300 ° C. There is a problem that characteristics and the like are impaired. Improvements have been attempted by adding various stabilizers. However, when high-speed processing is performed with a large processing machine, the resin is cross-linked or decomposed due to the shearing force of the extruder. Alternatively, the combination cannot be sufficiently stabilized, and a satisfactory product has not been obtained. In addition, due to the recent increase in the performance of polymerization catalysts used for the production of polyolefin resins, the production process has been increasingly replaced by the economically simplified gas-phase polymerization method instead of the slurry polymerization method. It is also an important issue to suppress the decomposition of the resin during processing due to the influence of the catalyst residue therein.

As a technique for imparting processing stability to a polyolefin resin, a method of suppressing heat and oxidative deterioration during processing by blending a phenolic stabilizer and a phosphorus-based stabilizer alone or in combination has conventionally been practiced. I have been. Specifically, JP-A-51-109050, JP-A-52-1068
No. 79, JP-A-57-209942, JP-A-62-3
No. 4934, JP-A-62-141066, JP-A-62
This is a method described in -135550 and the like.
In addition, polyolefin resins are widely used in food packaging and food containers because of their excellent food hygiene properties.For such applications, natural antioxidants and tocopherols that are harmless to the human body are used. Techniques for imparting processing stability by a blending method have also been used. (Japanese Patent Laid-Open No. 49-
No. 72338, JP-A-49-112944, JP-A-Showa 5
0-110442, JP-A-51-10855, JP-A-51-62843, JP-A-52-90547, JP-A-53-78248, JP-A-53-134574.
JP-A-53-114852, JP-A-54-550
No. 43, JP-A-55-5337, JP-A-58-966
No. 38, JP-A-61-188435, JP-A-62-8
No. 6036, JP-A-62-158737, JP-A-63
137,941, JP-A-63-105060, JP-A-2-225542, JP-A-2-102241, JP-A-3-43458. Some of these technologies
Among the phenolic stabilizers, BHT (2,6-di-tert-butyl-p-), which has been conventionally used for a wide range of applications because of its excellent processing stability and safety and its low cost.
Although a method for solving the deterioration of the color tone (yellowing) of a product caused by mixing of cresol) with tocopherols has been found, decomposition by mechanical shearing force during processing has not been solved at all. In other words, among the polyolefin-based resins, particularly in the case of a resin having a low melt fluidity, in other words, a resin having a high molecular weight, the conventional stabilization technology requires:
It is still insufficient to suppress deterioration due to molecular cutting, mainly due to mechanical shearing force in the extruder, and solving the above problem has been an important issue.

[0004]

SUMMARY OF THE INVENTION An object of the present invention is to solve the above-mentioned problem which has not been achieved by the prior art, namely, thermal and mechanical decomposition due to shearing force during processing of polyolefin resin. To provide a stabilized polyolefin resin composition.

[0005]

Means for Solving the Problems The inventors of the present invention have made intensive studies to solve this problem, and as a result, the combination of a specific tocopherol with another stabilizer at a specific compounding ratio has achieved the above-mentioned problems. We have found that we can do this and completed the present invention. That is, the present invention relates to a polyolefin-based resin and 100 parts by weight of the resin, wherein (A) a tocopherol is used in an amount of 0.1 ton.
001 to 1.0 parts by weight, and (B) 0.001 to 1.0 parts by weight of a phenolic stabilizer having a molecular weight of 300 or more,
(C) The present invention relates to a stabilized polyolefin-based resin composition containing 0.001 to 1.0 parts by weight of a phosphorus-based stabilizer. Further, the present invention relates to a resin composition wherein the polyolefin resin is a polypropylene resin. Further, the present invention provides the above-mentioned polypropylene-based resin,
The melt index measured at 30 ° C. is 0.01 to 3
The present invention relates to a resin composition which is a copolymer of propylene and ethylene and / or an α-olefin having 4 to 12 carbon atoms in a range of 0 g / 10 minutes.

[0006]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below in detail.
As the polyolefin resin used in the present invention, high-density polyethylene, linear low-density polyethylene which is a copolymer of ethylene and α-olefin, low-density polyethylene produced by high-pressure radical polymerization, homopolymer of propylene , Butene homopolymer, propylene
Ethylene random copolymer, propylene-α-olefin random copolymer, propylene-ethylene-α-olefin terpolymer, propylene and a copolymer component mainly composed of propylene in at least two or more stages. Examples include a polypropylene-based copolymer (sometimes referred to as a propylene-ethylene block copolymer) produced by polymerizing a copolymer component of ethylene and / or an α-olefin having 4 to 12 carbon atoms. Preferably, polypropylene produced by polymerizing a copolymer component mainly composed of propylene and a copolymer component of propylene and ethylene and / or an α-olefin having 4 to 12 carbon atoms in at least two or more stages. It is a system copolymer. As the α-olefin, an α-olefin having 4 to 12 carbon atoms is preferable, and 1-butene, 1-hexene and 1-octene are particularly preferable. The content of ethylene and / or an α-olefin having 4 to 12 carbon atoms in the copolymer is not particularly limited as long as the properties of the present invention are not impaired.
It is 1 to 20% by weight, preferably 1 to 10% by weight. These polyolefin resins can be used alone or as a blend of two or more.

The polyolefin resin used in the present invention includes a Ziegler type catalyst, a Ziegler-Natta type catalyst, a catalyst system comprising a combination of a transition metal compound of Group IV of the periodic table having a cyclopentadienyl ring and an alkylaluminoxane, Or a batch polymerization method using a catalyst system comprising a combination of a transition metal compound of Group IV of the periodic table having a cyclopentadienyl ring, a compound which reacts therewith to form an ionic complex, and an organoaluminum compound. And those produced by a continuous polymerization method or the like. As the polyolefin-based resin used in the present invention, those produced by various polymerization processes can be used. For example, those produced by a slurry polymerization method using an inert hydrocarbon solvent, a solvent polymerization method, a liquid phase polymerization method using no solvent, a gas phase polymerization method, or a liquid phase-gas phase polymerization method in which they are continuously performed. is there. In particular, those produced by a gas phase polymerization method are suitably used. Polyolefin resin used in the present invention, if necessary, to remove residual solvents and ultra-low molecular weight oligomers by-produced during production, etc.
What has been dried at a temperature not higher than the temperature at which the polyolefin-based resin melts can be used. For example, the drying method is described in JP-A-55-75410 and JP-A-25657.
The method described in No. 53 is performed. The polyolefin resin used in the present invention has a melt index measured at 230 ° C of 0.01 to 50 g / 10 minutes, preferably 0.1 to 30 g / 10 minutes, and more preferably 0.1 to 30 g / 10 minutes. It is in the range of 10 g / 10 minutes, and the effect is particularly great for those having a low melt index.

[0008] In the present invention, the tocopherols (A) to be blended with the polyolefin resin are used in an amount of 0.001 to 1.0 to 100 parts by weight of the polyolefin resin.
0 parts by weight are blended. Preferably, the amount is 0.001 to 0.5 part by weight, more preferably 0.01 to 0.3 part by weight. The phenolic stabilizer of the component (B) is used in an amount of 0.001 to 1.0 based on 100 parts by weight of the polyolefin resin.
It is blended by weight. Preferably, it is added in an amount of 0.001 to 0.5 part by weight, more preferably 0.01 to 0.5 part by weight. And the phenolic stabilizer referred to in the present invention needs to have a molecular weight of 300 or more. The phosphorus stabilizer of the component (C) is added in an amount of 0.001 to 1.0 part by weight based on 100 parts by weight of the polyolefin resin. Preferably 0.001 to 0.5 parts by weight, more preferably,
0.01 to 0.5 part by weight is blended. If the amount of these components is less than the above range or not added, the processing stability of the polyolefin resin is insufficiently improved and decomposition occurs during processing, thereby deteriorating various properties of the processed product. . Also, if the amount is large, it is economically disadvantageous, and the surface appearance deteriorates due to contamination of the processing machine at the time of processing, bleeding out of the product surface, etc., product color tone, odor In the case of a packaged food product, there is a deterioration in taste due to leakage into food, and this is not preferable from a hygienic point of view.

In the present invention, (A) tocopherols, (B) a phenolic stabilizer, and (C) a phosphorus-based stabilizer blended in a polyolefin resin, (A)
The weight ratio of (A) to the total weight of (B) and (C) is preferably in the following range. (A) / ((A) + (B) + (C)) = 0.05-0.
7 More preferably, it is 0.1 to 0.7, more preferably 0.1 to 0.4. If the ratio is out of the above range, the processing stability is insufficient, and the color tone is deteriorated. Tocopherols used in the present invention,
The following general formula (II)

[0010]

Embedded image Means a compound represented by In the formula, R ₁ , R ₂ and R ₃ represent hydrogen or a methyl group, and may be in any combination. R ₄ represents a hydrocarbon group having 1 to 16 carbon atoms, for example, a 4,8,12-trimethyltridecyl group {-
[(CH ₂ ) ₃ —CH (CH ₃ )] ₃ —CH ₃ }, 4,8,1
It represents a 2-trimethyl-3,7,11-tridecatrienyl group {-[(CH ₂ ) ₂ —CH ＝ C (CH ₃ )] ₃ —CH ₃ }. The former is called tocol and the latter is called tocotrienol, and all natural or synthetic tocopherols are represented by the general formula (II). The tocopherols may be a mixture of several homologs. Specifically, α-tocopherol (5,7,8-trimethyltocol), β-tocopherol
Tocopherol (5,8-dimethyltocol), γ-
Tocopherol (7,8-dimethyltocol), δ-
Tocopherol (8-methyltocol) and mixtures of two or more thereof. Particularly, vitamin E which is α-tocopherol is preferable. In addition, since tocopherols undergo performance changes such as deterioration of color tone due to oxidation, it is preferable that tocopherols are not so much oxidized. Those having higher purity are preferable, and generally have a purity of 90% or more, more preferably 95% or more.

As the phenol stabilizer (B) used in the present invention, a hindered phenol compound having a molecular weight of 300 or more is preferable. For example, tetrakis [methylene-3- (3 ′, 5′-di-t-butyl-4)
-Hydroxyphenyl) propionate] methane, octadecyl-3- (3,5-di-t-butyl-4-hydroxyphenyl) propionate, 3,9-bis [2-
{3- (3-t-butyl-4-hydroxy-5-methylphenyl) propionyloxy} -1,1-dimethylethyl] -2,4,8,10-tetraoxaspiro [5.
5] undecane, 1,3,5-tris 2- [3- (3,5
-Di-tert-butyl-4-hydroxyphenyl) propionyloxy] ethyl isocyanate, 1,3,5-trimethyl-2,4,6-tris (3,5-di-tert-butyl-4-hydroxybenzyl) benzene , Tris (3,5
-Di-t-butyl-4-hydroxybenzyl) isocyanurate, 1,3,5-tris (4-t-butyl-3-
(Hydroxy-2,6-dimethylbenzyl) isocyanurate, pentaerythrityl-tetrakis [3- (3,5
-Di-t-butyl-4-hydroxyphenyl) propionate], triethylene glycol-N-bis-3-
(3-t-butyl-5-methyl-4-hydroxyphenyl) propionate, 1,6-hexanediol bis
[3- (3,5-di-t-butyl-4-hydroxyphenyl) propionate], 2,2-thiobis-diethylenebis [3- (3,5-di-t-butyl-4-hydroxyphenyl) propionate ], 2,2'-methylene-
Bis- (4-methyl-6-t-butylphenol),
2,2′-methylene-bis- (4-ethyl-6-t-butylphenol), 2,2′-methylene-bis- (4,
6-di-t-butylphenol), 2,2′-ethylidene-bis- (4,6-di-t-butylphenol),
2,2'-butylidene-bis- (4-methyl-6-t-
Butylphenol), 4,4'-butylidenebis (3-
Methyl-6-tert-butylphenol), 2-tert-butyl-6- (3-tert-butyl-2-hydroxy-5-methylbenzyl) -4-methylphenylacrylate, 2,4
-Di-t-amyl-6- (1- (3,5-di-t-amyl-2-hydroxyphenyl) ethyl] phenyl acrylate, etc. Particularly, the following general formula (I)

[0012]

Embedded image (I) A phenolic compound having at least one group represented by the formula (wherein R ₁ and R _{2 each} represent hydrogen, a methyl group or a t-butyl group) is preferably used. Specifically, tetrakis [methylene-3- (3 ′, 5′-di-tert-butyl-4-hydroxyphenyl) propionate] methane,
Octadecyl-3- (3,5-di-t-butyl-4-hydroxyphenyl) propionate, 3,9-bis [2
-{3- (3-t-butyl-4-hydroxy-5-methylphenyl) propionyloxy} -1,1-dimethylethyl] -2,4,8,10-tetraoxaspiro [5,5] undecane, 1,3,5-tris 2- [3-
(3,5-di-t-butyl-4-hydroxyphenyl)
[Propionyloxy] ethyl isocyanate.

[0013] It is essential that the phenolic stabilizer has a molecular weight of 300 or more. For example, BHT (2,6-di-t-butyl-p-cresol), which has been conventionally used for a wide range of applications, has a molecular weight of 300 or less and is outside the scope of the present invention. BHT is highly likely to cause color deterioration (yellowing) due to mixing with tocopherols.

Further, (C) phosphorus-based stabilizers include tris (2,4-di-t-butylphenyl) phosphite,
Tetrakis (2,4-di-t-butylphenyl) -4,
4'-biphenylene phosphite, tris (nonylphenyl) phosphite, distearylpentaerythritol diphosphite, bis (2,4-di-tert-butylphenyl) pentaerythritol diphosphite, bis (2,6-di- t-butyl-4-methylphenyl) pentaerythritol diphosphite, 2-[[2,4
8,10-tetrakis (1,1-dimethylethyl) dibenzo [d, f] [1,3,2] dioxaphosphepin-6-yl] oxy] -N, N-bis [2-[[2, 4,
8,10-tetrakis (1,1-dimethylethyl) dibenzo [d, f] [1,3,2] dioxaphosphepin-6-yl] oxy] -ethyl] ethanamine.

In terms of food hygiene such as handling and odor,
Phosphorus stabilizers having excellent hydrolysis resistance are preferred, for example, tris (2,4-di-t-butylphenyl) phosphite, 2-[[2,4,8,10-tetrakis (1,
1-dimethylethyl) dibenzo [d, f] [1,3
2] dioxaphosphepin-6-yl] oxy] -N,
N-bis [2-[[2,4,8,10-tetrakis (1,1-dimethylethyl) dibenzo [d, f] [1,
3,2] dioxaphosphepin-6-yl] oxy]
-Ethyl] ethanamine, especially Tris (2,4
(Di-t-butylphenyl) phosphite is preferably used.

The polyolefin resin composition used in the present invention may contain other additives such as a neutralizing agent (hydrotalcite, a metal salt of a higher fatty acid), a lubricant, and a charge as long as the object of the present invention is not impaired. An inhibitor, an anti-blocking agent, an ultraviolet absorber, a weathering agent and the like may be added. If necessary, a clarifying agent, a nucleating agent, or an inorganic filler such as calcium carbonate, an alkaline earth metal compound, silica, talc, or glass fiber can be added. The polypropylene-based resin composition used in the present invention may optionally contain a resin other than the polyolefin-based resin used in the present invention as long as the object of the present invention is not impaired. For example, acrylic resins, styrene-butadiene-styrene copolymers, styrene-isoprene-styrene copolymers hydrogenated styrene-based copolymers, and other elastomers can be blended.

The polyolefin resin composition of the present invention comprises:
The polyolefin-based resin and the stabilizer can be melt-kneaded in the presence or absence of an organic peroxide using, for example, a melt extruder or a Banbury mixer, and the melt flow rate can be adjusted and pelletized. . The reaction can be performed in the presence or absence of an inert gas such as nitrogen, as necessary.

The polyolefin resin composition of the present invention comprises:
It can be manufactured into various products. The polyolefin resin product is produced by a method generally used in industry, for example, a T-die film forming method, a tubular film forming method, a compression molding method, an injection molding method, a vacuum molding method, or the like. The method of manufacture is preferred. It is also possible to form a multilayer by bonding two or more kinds of resins as necessary. The polyolefin-based resin composition of the present invention is commercialized by the above processing method, and can be used for various applications. For example, it can be used for packaging of foods, fibers, miscellaneous goods, etc., medical use, or use of automobile parts, home electric parts and the like.

[0019]

The present invention will be described in more detail with reference to the following Examples and Comparative Examples, but the present invention is not limited thereto. The tocopherols, phenolic stabilizers and phosphorus stabilizers used are shown below. (A): dl-α-tocopherol (vitamin E), trade name: RIKEN E Oil 1000 (B-1): tetrakis [methylene-3- (3 ′, 5 ′)
-Di-t-butyl-4-hydroxyphenyl) propionate] methane (manufactured by Ciba Specialty Chemicals: Irganox 1010) (B-2): octadecyl-3- (3,5-di-t-butyl-4) -Hydroxyphenyl) propionate (manufactured by Ciba Specialty Chemicals, Inc .: trade name Irga)
nox1076) (B-3): 3,9-bis [2- {3- (3-t-butyl-4-hydroxy-5-methylphenyl) propionyloxy} -1,1-dimethylethyl] -2,4 , 8,
10-tetraoxaspiro [5.5] undecane (Sumitomo Chemical Co., Ltd .: trade name Sumilyzer GA80) (B-4): 1,3,5-tris2 [3- (3,5-di-t) -Butyl-4-hydroxyphenyl) propionyloxy] ethyl isocyanate (trade name Goodlite 3)
125) (C): Tris (2,4-di-t-butylphenyl) phosphite (manufactured by Ciba Specialty Chemicals):
Product name Irgafos 168)

The measured values of each item in the examples were determined by the following methods. (1) Melt index (MI: g / 10 minutes) It was based on JIS K7210. The measurement temperature is 230 ° C. (2) Intrinsic viscosity ([η]: dl / g) The measurement was performed in tetralin at 135 ° C. using an Ubbelohde viscometer. (3) Ethylene content (wt%) Measured by ¹³ C-nuclear magnetic resonance spectroscopy. (4) Shear stability A kneading test was performed using a batch-type small twin-screw kneader (Labo Plastmill manufactured by Toyo Seiki Co., Ltd.) under the conditions of a sample of 60 g, a set temperature of 200 ° C., a rotation speed of 80 rpm, and a kneading time of 10 minutes. The melt index of the kneaded product was measured by the method (1), and the values before and after the test were compared to make a judgment. The smaller the MI value, the better the stability. (5) Color difference (Yellow index: YI) The kneaded product was heated and melted at 230 ° C. for 5 minutes using a hot press molding machine, and then cooled at 30 ° C. for 5 minutes to prepare a test piece having a thickness of 1 mm. The YI value of this test piece was measured using a color computer manufactured by Suga Test Instruments.

Example 1 A polypropylene powder (propylene-propylene) produced by a gas phase polymerization method using a solid catalyst component prepared by the method described in Example 2 of JP-A-7-216017.
Ethylene block copolymer: ethylene content = 10.3
(Wt%), [η] = 3.20 (dl / g)) 100 parts by weight of calcium stearate, 0.05 parts by weight of vitamin E (A), phenolic stabilizer ( B-1) was added in an amount of 0.15 part by weight, and the phosphorus-based stabilizer (C) was added in an amount of 0.05 part by weight. This mixture is
The mixture was heated and melt-kneaded at a temperature of 220 ° C. with a single-screw extruder of mmφ to form pellets. The MI of the pellet is 0.27
(G / 10 minutes). Next, the pellets were subjected to a shear stability test and a color difference measurement.
The results are shown in Tables 1 and 2.

Examples 2 to 4 In Example 1, except that (B-2), (B-3) and (B-4) were used in place of the phenolic stabilizer (B-1). The procedure was the same as described in 1. The results are shown in Tables 1 and 2.

Comparative Examples 1-4 In Examples 1-4, vitamin E (A) was not added,
The procedure was performed in the same manner as in Example 1, except that 0.2 parts by weight of the phenolic stabilizer and 0.05 parts by weight of the phosphorus stabilizer (C) were used. The results are shown in Tables 1 and 2.

Comparative Example 5 In Example 1, 0.05 parts by weight of vitamin E (A) and 0.2 parts by weight of phenolic stabilizer (B-1) were added without adding the phosphorus stabilizer (C). Except having used, it carried out similarly to the method of Example 1. The results are shown in Tables 1 and 2.

Examples 5 to 7 In Example 1, except that the addition amounts and ratios of vitamin E (A) and phenolic stabilizer (B-1) were changed.
It carried out similarly to the method of Example 1. The results are shown in Tables 1 and 2.

Example 8 A polypropylene powder (propylene-ethylene block) produced by a slurry polymerization method using a Ti—Cl 3 / diethylaluminum chloride type catalyst (manufactured by Solvay) in place of the polypropylene powder used in Example 1. Copolymer: ethylene content = 7.8 (wt)
%), [Η] = 3.16 (dl / g)), and the type, amount and evaluation of the stabilizer used were the same as in Example 1. The results are shown in Tables 3 and 4.

Comparative Example 6 In Example 8, except that the vitamin E (A) and the phosphorus-based stabilizer (C) were not added and the phenol-based stabilizer (A-1) was used only in an amount of 0.2 part by weight, It carried out similarly to the method of Example 8. The results are shown in Tables 3 and 4.

Comparative Examples 7 and 8 The procedure of Comparative Example 6 was repeated except that the amount and ratio of the phosphorus-based stabilizer (C) were changed. The results are shown in Tables 3 and 4.

Comparative Example 9 The procedure of Example 8 was repeated except that the phenol stabilizer (A-1) and the phosphorus stabilizer (C) were not added, and that only vitamin E (A) was used in an amount of 0.05 part by weight. It carried out similarly to the method of Example 8. The results are shown in Tables 3 and 4.

[0030]

[Table 1]

[0031]

[Table 2]

[0032]

[Table 3]

[0033]

[Table 4]

[0034]

The polyolefin resin composition of the present invention is highly stable against thermal and mechanical decomposition due to shearing during processing, and has a good color tone after processing.

Claims (9)

[Claims] 1. A polyolefin resin and 100 parts by weight of the resin, (A) tocopherols 0.001 to 1.
0 parts by weight, (B) 0.001 to 1.0 parts by weight of a phenol stabilizer having a molecular weight of 300 or more, and (C) 0.001 to 1.0 parts by weight of a phosphorus stabilizer. A stabilized polyolefin resin composition characterized by the following: 2. The resin composition according to claim 1, wherein the polyolefin resin is a polypropylene resin. 3. A polypropylene resin having a melt index measured at 230.degree. C. in the range of 0.01 to 30 g / 10 minutes and a copolymer of propylene and ethylene and / or an .alpha.-olefin having 4 to 12 carbon atoms. The resin composition according to claim 2, which is a polymer. 4. A propylene polymer or propylene copolymer, which has a melt index measured at 230 ° C. of 0.01 to 30 g / 10 min and is produced in at least two or more polymerization steps. Polymer component, propylene and ethylene and / or carbon number 4 to
The resin composition according to claim 3, comprising a copolymer component of α-olefin of No. 12. 5. The resin composition according to claim 1, wherein the tocopherol component (A) is vitamin E. 6. The phenolic stabilizer of component (B) is at least one selected from phenolic compounds having at least one group represented by the following general formula (I).
The resin composition according to 2, 3, or 4. Embedded image (I) (wherein, R ₁ and R _{2 each} represent hydrogen, a methyl group or a t-butyl group.) 7. The phenolic stabilizer (B) is tetrakis [methylene-3- (3 ′, 5′di-tert-butyl-4-hydroxyphenyl) propionate] methane, octadecyl-3- (3,5- Di-tert-butyl-4-hydroxyphenyl) propionate, 3,9-bis [2- {3-
(3-t-butyl-4-hydroxy-5-methylphenyl) propionyloxy {-1,1-dimethylethyl]
-2,4,8,10-tetraoxaspiro [5.5] undecane and 1,3,5-tris2- [3- (3,5-
The resin composition according to claim 6, which is at least one member selected from the group consisting of di-t-butyl-4-hydroxyphenyl) propionyloxy] ethyl isocyanate. 8. The method according to claim 1, wherein the phosphorus-based stabilizer (C) is tris (2,4-di-t-butylphenyl) phosphite.
The resin composition according to 2, 3, or 4. 9. The weight ratio of the component (A) to the total amount of the tocopherols of the component (A), the phenolic stabilizer of the component (B) and the phosphorus stabilizer of the component (C) is represented by the following formula (A). /
The resin composition according to claim 1, wherein ((A) + (B) + (C)) = 0.05 to 0.70.