JP2016222899A - Cyclic olefin resin composition film - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a cyclic olefin resin composition film less in defect.SOLUTION: A cyclic olefin resin composition film contains a cyclic olefin resin and antioxidant and the oxidant satisfies at least one of following (1) to (3) conditions. (1) content of lithium ion contained in the antioxidant is 0.4 ppm or less. (2) content of cation contained in the antioxidant is 0.9 ppm or less. (3) content of chloride ion contained in the antioxidant is 0.1 ppm or less.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a cyclic olefin resin composition film containing a cyclic olefin resin and an antioxidant.

  Cyclic olefin resin is an amorphous and thermoplastic olefin resin that has a cyclic olefin skeleton in its main chain, has excellent optical properties (transparency, low birefringence), low water absorption, It has excellent performance such as dimensional stability and high moisture resistance based thereon (see, for example, Patent Documents 1 to 5). Therefore, films or sheets made of cyclic olefin resins are expected to be developed for various optical applications such as retardation films, polarizing plate protective films, light diffusion plates, and moisture proof packaging applications such as pharmaceutical packaging and food packaging. Yes.

JP 2001-139756 A JP 2009-234982 A Japanese Patent Laid-Open No. 2004-156048 JP 2004-359819 A JP 2000-86870 A

  The cyclic olefin-based resin needs to be molded and processed at a higher temperature due to the high glass transition point. When molding is performed under such a high temperature condition, the resulting molded product is colored and colorless transparency is impaired, or the molded product is a resin (cyclic polyolefin resin) and / or an additive (containing component). There is a problem that burns (black) due to thermal decomposition occur.

  For example, when a film is melt-molded using a cyclic olefin-based resin, gelation due to shearing between the resins is likely to occur, and it is necessary to increase the molding temperature (for example, 280 to 360 ° C.), and burnt (black) May occur. In a thin film product such as a transparent conductive film substrate, even a slight burn causes a problem in quality.

  Therefore, while maintaining the excellent optical properties (retardation, haze) and toughness of the cyclic polyolefin resin, defects (for example, coloring due to oxidative degradation or thermal decomposition) It is required not to generate a burn (black).

  This invention is made | formed in view of such a conventional situation, and provides the cyclic olefin resin composition film with few defects.

  As a result of intensive studies, the inventors of the present application have found that the above problem can be solved by setting the content of specific ions contained in the antioxidant to a predetermined value or less.

That is, the cyclic olefin resin composition film according to the present invention contains a cyclic olefin resin and an antioxidant, and the antioxidant satisfies at least one of the following conditions (1) to (3). .
(1) The content of lithium ions contained in the antioxidant is 0.4 ppm or less.
(2) The content of the cation contained in the antioxidant is 0.9 ppm or less.
(3) The content of chloride ions contained in the antioxidant is 0.1 ppm or less.

  According to the present invention, when the antioxidant satisfies at least one of the above conditions (1) to (3), defects in the cyclic olefin resin composition film can be suppressed.

FIG. 1 is a graph showing the relationship between the content of lithium ions contained in the antioxidant and the number of defects. FIG. 2 is a graph showing the relationship between the content of cations contained in the antioxidant and the number of defects. FIG. 3 is a graph showing the relationship between the content of chloride ions contained in the antioxidant and the number of defects.

Hereinafter, embodiments of the present invention will be described in detail in the following order with reference to the drawings.
1. 1. Cyclic olefin resin composition film Example

<1. Cyclic Olefin Resin Composition Film>
The cyclic olefin resin composition film according to the present embodiment contains a cyclic olefin resin and an antioxidant, and the antioxidant satisfies at least one of the following conditions (1) to (3).
(1) The content of lithium ions contained in the antioxidant is 0.4 ppm or less.
(2) The content of the cation contained in the antioxidant is 0.9 ppm or less.
(3) The content of chloride ions contained in the antioxidant is 0.1 ppm or less.

  According to the cyclic olefin resin composition film according to the present embodiment, defects can be suppressed. Further, the optical properties (retardation, haze) and toughness can be improved.

  In the cyclic olefin-based resin composition used for the cyclic olefin-based resin composition film, when each of the ions contained in the antioxidant is excessively present in the vicinity of the antioxidant, the respective ions are prevented from being oxidized. It acts on the agent and tends to lower the function of the antioxidant. As a result, defects tend to occur when a film is melt-molded using the cyclic olefin-based resin composition. As said each ion contained in antioxidant, what originates in the manufacturing process of antioxidant is mentioned. For example, when a phenolic antioxidant obtained using a lithium catalyst is used, the antioxidant is likely to contain excessive lithium.

  On the other hand, in the cyclic olefin-based resin composition, each of the above ions derived from the cyclic olefin resin is unlikely to exist in the vicinity of the antioxidant, so it is considered difficult to contribute to a decrease in the function of the antioxidant.

  The cyclic olefin-based resin composition film according to the present embodiment is a film or a sheet. The cyclic olefin-based resin composition film preferably has a thickness of 0.1 μm to 2 mm, and more preferably 1 μm to 1 mm. Hereinafter, the cyclic olefin resin, the antioxidant and the like used for the cyclic olefin resin composition film will be described in detail.

[Cyclic olefin resin]
The cyclic olefin-based resin is a polymer compound having a main chain composed of carbon-carbon bonds and having a cyclic hydrocarbon structure in at least a part of the main chain. This cyclic hydrocarbon structure is introduced by using a compound (cyclic olefin) having at least one olefinic double bond in the cyclic hydrocarbon structure as represented by norbornene or tetracyclododecene as a monomer. Is done.

  Cyclic olefin resins include cyclic olefin addition (co) polymers or hydrogenated products thereof (A), cyclic olefin and α-olefin addition copolymers or hydrogenated products thereof (B), cyclic olefin ring-opening ( Co) polymers or their hydrogenated products (C).

  Specific examples of the cyclic olefin include: cyclopentene, cyclohexene, cyclooctene; one-ring cyclic olefin such as cyclopentadiene, 1,3-cyclohexadiene; bicyclo [2.2.1] hept-2-ene (common name: norbornene) ), 5-methyl-bicyclo [2.2.1] hept-2-ene, 5,5-dimethyl-bicyclo [2.2.1] hept-2-ene, 5-ethyl-bicyclo [2.2. 1] Hept-2-ene, 5-butyl-bicyclo [2.2.1] hept-2-ene, 5-ethylidene-bicyclo [2.2.1] hept-2-ene, 5-hexyl-bicyclo [ 2.2.1] hept-2-ene, 5-octyl-bicyclo [2.2.1] hept-2-ene, 5-octadecyl-bicyclo [2.2.1] hept-2-ene, 5- Methylidene Bicyclo [2.2.1] hept-2-ene, 5-vinyl-bicyclo [2.2.1] hept-2-ene, 5-propenyl-bicyclo [2.2.1] hept-2-ene, etc. A bicyclic olefin of

Tricyclo [4.3.0.1 ^2,5 ] deca-3,7-diene (common name: dicyclopentadiene), tricyclo [4.3.0.1 ^2,5 ] dec-3-ene; tricyclo [ 4.4.0.1 ^2,5 ] undeca-3,7-diene or tricyclo [4.4.0.1 ^2,5 ] undeca-3,8-diene or a partially hydrogenated product thereof (or cyclopentadiene) And cyclohexene adduct), tricyclo [4.4.0.1 ^2,5 ] undec-3-ene;
5-cyclopentyl-bicyclo [2.2.1] hept-2-ene, 5-cyclohexyl-bicyclo [2.2.1] hept-2-ene, 5-cyclohexenylbicyclo [2.2.1] hepta 3-cyclic olefins such as 2-ene and 5-phenyl-bicyclo [2.2.1] hept-2-ene;

Tetracyclo [4.4.0.1 ^2,5 . 1 ^7,10 ] dodec-3-ene (also simply referred to as tetracyclododecene), 8-methyltetracyclo [4.4.0.1 ^2,5 . 1 ^7,10 ] dodec-3-ene, 8-ethyltetracyclo [4.4.0.1 ^2,5 . 1 ^7,10 ] dodec-3-ene, 8-methylidenetetracyclo [4.4.0.1 ^2,5 . 1 ^7,10 ] dodec-3-ene, 8-ethylidenetetracyclo [4.4.0.1 ^2,5 . 1 ^7,10 ] dodec-3-ene, 8-vinyltetracyclo [4.4.0.1 ^2,5 . 1 ^7,10 ] dodec-3-ene, 8-propenyl-tetracyclo [4.4.0.1 ^2,5 . 1 ^7,10 ] tetracyclic olefins such as dodec-3-ene;

8-cyclopentyl-tetracyclo [4.4.0.1 ^2,5 . 1 ^7,10 ] dodec-3-ene, 8-cyclohexyl-tetracyclo [4.4.0.1 ^2,5 . 1 ^7,10 ] dodec-3-ene, 8-cyclohexenyl-tetracyclo [4.4.0.1 ^2,5 . 1 ^7,10 ] dodec-3-ene, 8-phenyl-cyclopentyl-tetracyclo [4.4.0.1 ^2,5 . 1 ^7,10 ] dodec-3-ene; tetracyclo [7.4.1 ^3,6 . 0 ^1,9 . 0 ^2,7 ] tetradeca-4,9,11,13-tetraene (also referred to as 1,4-methano-1,4,4a, 9a-tetrahydrofluorene), tetracyclo [8.4.1 ^4,7 . 0 ^1,10 . 0 ^3,8 ] pentadeca-5,10,12,14-tetraene (also called 1,4-methano-1,4,4a, 5,10,10a-hexahydroanthracene); pentacyclo [6.6.1]. ^.1,3,6 . 0 ^2,7 . 0 ^9,14 ] -4-hexadecene, pentacyclo [6.5.1.1 ^3,6 . 0 ^2,7 . 0 ^9,13] -4-pentadecene, pentacyclo [7.4.0.0 ^2,7. 1 ^3,6 . 1 ^10,13] -4-pentadecene; heptacyclo [8.7.0.1 ^2,9. 1 ^4,7 . 1 ^{11, 17} . 0 ^3,8 . 0 ^12,16 ] -5-eicosene, heptacyclo [8.7.0.1 ^2,9 . 0 ^3,8 . 1 ^4,7 . 0 ^12,17 . 1 ^13,16 ] ^-14-eicosene ; and polycyclic cyclic olefins such as a tetramer of cyclopentadiene. These cyclic olefins can be used alone or in combination of two or more.

  Specific examples of the α-olefin copolymerizable with the cyclic olefin include ethylene, propylene, 1-butene, 1-pentene, 1-hexene, 3-methyl-1-butene, 3-methyl-1-pentene, 3 -Ethyl-1-pentene, 4-methyl-1-pentene, 4-methyl-1-hexene, 4,4-dimethyl-1-hexene, 4,4-dimethyl-1-pentene, 4-ethyl-1- 2-20 carbon atoms such as hexene, 3-ethyl-1-hexene, 1-octene, 1-decene, 1-dodecene, 1-tetradecene, 1-hexadecene, 1-octadecene, 1-eicosene, preferably carbon number 2-8 alpha olefins etc. are mentioned. These α-olefins can be used alone or in combination of two or more. As these α-olefins, those contained in the range of 5 to 200% with respect to the cyclic polyolefin can be used.

  There are no particular limitations on the polymerization method of the cyclic olefin or the cyclic olefin and the α-olefin and the hydrogenation method of the obtained polymer, and it can be carried out according to a known method.

  In the present embodiment, an addition copolymer of ethylene and norbornene is preferably used as the cyclic olefin-based resin.

  There is no restriction | limiting in particular in the structure of cyclic olefin resin, Although it may be chain | strand shape, a branched form, or bridge | crosslinking form, Preferably it is linear.

  The molecular weight of the cyclic olefin-based resin is 5,000 to 300,000, preferably 10,000 to 150,000, and more preferably 15,000 to 100,000, as determined by the GPC method. If the number average molecular weight is too low, the mechanical strength decreases, and if it is too high, the moldability deteriorates.

  In addition, the cyclic olefin-based resin has polar groups (for example, a carboxyl group, an acid anhydride group, an epoxy group, an amide group, an ester group, a hydroxyl group, etc.) on the aforementioned cyclic olefin-based resins (A) to (C). A compound (D) obtained by grafting and / or copolymerizing an unsaturated compound (u) having the above compound may be included. The cyclic olefin resins (A) to (D) may be used in combination of two or more.

  Examples of the unsaturated compound (u) include (meth) acrylic acid, maleic acid, maleic anhydride, itaconic anhydride, glycidyl (meth) acrylate, alkyl (meth) acrylate (carbon number 1 to 10) ester, maleic acid Alkyl (C1-C10) ester, (meth) acrylamide, (meth) acrylic acid-2-hydroxyethyl, etc. are mentioned.

  By using the modified cyclic olefin resin (D) obtained by grafting and / or copolymerizing the unsaturated compound (u) having a polar group, the affinity with a metal or a polar resin can be increased, so that vapor deposition, sputtering, coating It is possible to increase the strength of various secondary processing such as adhesion, and is suitable when secondary processing is required. However, the presence of the polar group has a drawback of increasing the water absorption rate of the cyclic olefin resin. Therefore, the content of polar groups (for example, carboxyl group, acid anhydride group, epoxy group, amide group, ester group, hydroxyl group, etc.) is preferably 0 to 1 mol / kg per kg of cyclic olefin resin.

[Antioxidant]
The antioxidant is normally used in the field of resin materials or rubber materials, and satisfies at least one of the above-described conditions (1) to (3), that is, the ion content condition.

  (1) The content of lithium ions contained in the antioxidant is 0.4 ppm or less, preferably 0.3 ppm or less, and more preferably 0.2 ppm or less. If the lithium ion content exceeds 0.4 ppm, the effect (thermal stability improvement effect) of the antioxidant is reduced, and it becomes difficult to suppress defects.

  (2) The content of the cation contained in the antioxidant is 0.9 ppm or less, preferably 0.7 ppm or less, and more preferably 0.6 ppm or less. The cation content includes the lithium ion content. If the cation content exceeds 0.9 ppm, the effect of the antioxidant (thermal stability improving effect) is reduced, and it becomes difficult to suppress defects.

  (3) The content of chloride ions contained in the antioxidant is 0.1 ppm or less, preferably 0.095 ppm or less, more preferably 0.080 ppm or less, and 0.050 ppm or less. More preferably it is. If the chloride ion content exceeds 0.1 ppm, the effect of the antioxidant (thermal stability improving effect) becomes small, and it becomes difficult to suppress defects.

  In particular, the antioxidant contains at least the above conditions (1) or (3), that is, the content of lithium ions contained in the antioxidant is 0.4 ppm or less, and the chloride contained in the antioxidant. It is preferable to satisfy any one of the content of the physical ions being 0.1 ppm or less, and it is more preferable to satisfy all of the above conditions (1) to (3).

  The action mechanism of the content of each ion and the thermal stability is not clear, but for example, if lithium ions are excessively present in the composition, the lithium ions act on the antioxidant during the extrusion process, and the effect of the antioxidant It is thought that will be suppressed. In particular, since the cyclic olefin resin has a high melting temperature, the suppression of the effect of the antioxidant becomes remarkable.

  Specific examples of the antioxidant include phenolic antioxidants and phosphorus antioxidants, and phenolic antioxidants are preferable from the viewpoint of more effectively suppressing the number of defects. Specific examples of phenolic antioxidants include vitamin E, tetrakis- (methylene-3- (3 ′, 5′-di-t-butyl-4′-hydroxyphenyl) propionate) methane, 2,5-di- t-butylhydroquinone, 2,6-di-t-butyl-p-cresol, 4,4'-thiobis- (6-t-butylphenol), 2,2'-methylene-bis- (4-methyl-6 t-butylphenol), octadecyl-3- (3 ′, 5′-di-t-butyl-4′-hydroxyphenyl) propionate, 4,4′-thiobis- (6-t-butylphenol), 2-t-butyl -6- (3-t-butyl-2-hydroxy-5-methylbenzyl) -4-methylphenyl acrylate, pentaerythritol tetrakis (3-laurylthiopropionate) Pentaerythritol tetrakis [3- (3,5-di-t-butyl-4-hydroxyphenyl) propionate], 2,6-di- (t-butyl) -4-methylphenol, 2,2'-methylenebis- (6-t-butyl-p-cresol), 1,3,5-tris (3,5-t-butyl-4-hydroxybenzyl) -1,3,5-triazine-2,4,6- (1H , 3H, 5H) -trione, 2,6-di-t-butyl-4- (4,6-bis (octylthio) -1,3,5-triazin-2-ylamino) phenol, and the like. As a commercially available phenolic antioxidant, IRGANOX 1010 (manufactured by BASF Japan Ltd.), ADK STAB AO-60 (manufactured by ADEKA Corporation) and the like can be used.

  Specific examples of phosphorus antioxidants include 2,2′-methylenebis (4,6-di-t-butylphenyl) octyl phosphite, tris (2,4-di-t-butylphenyl) phosphite, tri Phenyl phosphite, tris (nonylphenyl) phosphite, tris (2-ethylhexyl) phosphite, trisdecyl phosphite, tris (tridecyl) phosphite, diphenyl mono (2-ethylhexyl) phosphite, diphenyl monodecyl phosphite, di Decyl monophenyl phosphite, diphenyl mono (tridecyl) phosphite, dilauryl hydrogen phosphite, diphenyl hydrogen phosphite, tetraphenyl dipropylene glycol diphosphite, tetraphenyl tetra (tridecyl) pentaerythri Tetraphosphite, tetra (tridecyl) -4,4'-isopropylidene diphenyl diphosphite, bis (nonylphenyl) pentaerythritol diphosphite, distearyl pentaerythritol diphosphite, hydrogenated bisphenol A pentaerythritol phosphite Examples thereof include phytopolymer, bis (2,4-di-t-butylphenyl) pentaerythritol diphosphite, bis (2,4-di-t-butyl-3-methylphenyl) pentaerythritol diphosphite, and the like.

  As for content of antioxidant, 0.05-5 mass parts is preferable normally with respect to a total of 100 mass parts of cyclic olefin resin and an elastomer, and 0.1-3 mass parts is more preferable. By setting the content of the antioxidant to 0.05 parts by mass or more, the function of the antioxidant (antioxidant effect) can be more effectively achieved. Moreover, by setting the content of the antioxidant to 5 parts by mass or less, the quality of the cyclic olefin resin composition such as mechanical strength and glass transition temperature is reduced, and the volatilization of the cyclic olefin resin composition is volatilized. An increase in components can be more effectively suppressed. Antioxidants may be used alone or in combination of two or more. When using 2 or more types of antioxidant, it is preferable that the total amount satisfy | fills the said numerical range.

  The cyclic olefin-based resin composition film may contain various compounding agents as necessary within a range not impairing the characteristics thereof. The various compounding agents are not particularly limited as long as they are usually used in thermoplastic resin compositions. For example, elastomers, ultraviolet absorbers, light stabilizers, plasticizers, lubricants, antistatic agents, flame retardants. , Coloring agents such as dyes and pigments, near infrared absorbers, compounding agents such as fluorescent brighteners, and fillers.

  As the elastomer, a styrene elastomer is preferable. By containing a styrene-based elastomer, the toughness of the film can be further improved. Hereinafter, the styrene elastomer will be described.

[Styrene elastomer]
The styrenic elastomer is a copolymer of styrene and a conjugated diene such as butadiene or isoprene, and / or a hydrogenated product thereof. The styrene elastomer is a block copolymer having styrene as a hard segment and conjugated diene as a soft segment, and does not require a vulcanization step and is preferably used. Further, the hydrogenated one is more preferable because it has higher thermal stability.

  Examples of styrenic elastomers include styrene / butadiene / styrene block copolymers, styrene / isoprene / styrene block copolymers, styrene / ethylene / butylene / styrene block copolymers, and styrene / ethylene / propylene / styrene block copolymers. Examples thereof include styrene and butadiene block copolymers.

  In addition, styrene / ethylene / butylene / styrene block copolymer, styrene / ethylene / propylene / styrene block copolymer, styrene / butadiene block copolymer (hydrogenation) in which double bond of conjugated diene component is eliminated by hydrogenation May also be used. Hydrogenated styrenic elastomers are preferred because of high tear strength and small haze increase after environmental preservation.

  The molecular weight of the styrene elastomer is 5,000 to 300,000, preferably 10,000 to 150,000, and more preferably 20,000 to 100,000, as determined by the GPC method. If the number average molecular weight is too low, the mechanical strength decreases, and if it is too high, the moldability deteriorates.

  When the styrene elastomer is contained, the weight ratio of the cyclic olefin resin to the styrene elastomer (cyclic olefin resin: styrene elastomer) is preferably 60:40 to 95: 5, and 85:15 to 95: 5. It is more preferable that By setting it as such a range, the toughness of the film obtained can be improved more.

[Characteristics of cyclic olefin resin composition film]
The cyclic olefin-based resin composition film preferably has a retardation of 10.0 nm or less, more preferably 7.0 nm or less, and even more preferably 5.0 nm or less. The value of retardation means the value measured about the in-plane retardation R0 of the film using the optical material inspection apparatus (made by Otsuka Electronics Co., Ltd., trade name: RETS-100). When the retardation satisfies the above range, the target optical characteristics are more easily satisfied.

  The cyclic olefin-based resin composition film preferably has a haze of 2.0% or less, and more preferably 1.5% or less. The haze value refers to a value measured using a haze meter (product name: HM150, manufactured by Murakami Color Research Laboratory Co., Ltd.) for a film having a thickness of 50 μm. When the haze value satisfies the above range, the characteristics from the initial setting are maintained and the desired optical characteristics are more easily satisfied.

  The cyclic olefin-based resin composition film preferably has a tear strength of 50 N / mm or more, more preferably 60 N / mm or more, and even more preferably 70 N / mm or more. When the tear strength satisfies the above range, the film can be more effectively prevented from being broken during production and use.

<Method for Producing Cyclic Olefin Resin Composition Film>
The cyclic olefin resin composition film can be formed using the cyclic olefin resin composition containing the cyclic olefin resin and the antioxidant described above. For example, it can be obtained by melting the cyclic olefin resin composition at a temperature in the range of 210 to 300 ° C. and extruding the molten cyclic olefin resin composition into a film. The cyclic olefin-based resin composition film may be non-stretched, uniaxially stretched, or biaxially stretched. The manufacturing method of a film is not specifically limited, The extrusion method is preferable.

  The cyclic olefin-based resin composition film is suitable for various optical uses, for example, a retardation film, a polarizing plate protective film, a light diffusing plate and the like, particularly a prism sheet and a liquid crystal cell substrate.

<3. Example>
Examples of the present invention will be described below. In this example, a cyclic olefin-based resin composition film was produced, and the number of defects, retardation R0, tear strength, and haze of the obtained film were evaluated. The present invention is not limited to these examples.

[Defect count]
The number of defects having a size of 5 μm or more (coloring due to oxidative deterioration, burning due to thermal decomposition (black)) was counted with a visual and optical microscope (500 times) for a 25 mm square film. Those having a defect count of 100 or less were evaluated as “◯”, and those having a defect count exceeding 100 were evaluated as “x”. When the number of defects is 100 or less, the number of defects generated in an actual production line can be greatly reduced.

[Retardation]
The retardation was measured for the in-plane retardation R0 of the film using an optical material inspection apparatus (trade name: RETS-100, manufactured by Otsuka Electronics Co., Ltd.).

[Tear strength (right-angle tear)]
The tear strength was measured according to JISK7128 for a film having a thickness of 50 μm. A No. 3 type test piece was used as a test piece, and measurement was performed at a test speed of 200 mm / min using a tensile tester (AG-X, manufactured by Shimadzu Corporation).

[Haze]
Haze was measured on a film having a thickness of 50 μm using a haze meter (product name: HM150, manufactured by Murakami Color Research Laboratory Co., Ltd.).

[Cyclic olefin resin]
TOPAS6013-S04 (manufactured by Polyplastics Co., Ltd., chemical name: addition copolymer of ethylene and norbornene) was used as the cyclic olefin resin.

[Styrene elastomer]
As the styrene elastomer, Tuftec H1041 (styrene / ethylene / butylene / styrene block copolymer, manufactured by Asahi Kasei Chemicals Corporation) was used.

[Antioxidant]
Any of the following antioxidants A to F was used. Each ion concentration below was analyzed and measured by an ion chromatogram (manufactured by DIONEX, product name: DX-320). About 0.2 g of GI-1000 was placed in a PP container (50 mL) together with 10 mL of ultrapure water, and left in a 100 ° C. oven for 10 hours to obtain a measurement sample.

<Antioxidant A>
IRGANOX 1010 (manufactured by BASF Japan Ltd., lot number A1, cation content: 0.5 ppm, lithium ion content: 0.2 ppm, chloride ion content: 0.048 ppm)

<Antioxidant B>
IRGANOX 1010 (manufactured by BASF Japan Ltd., lot number B1, cation content: 0.6 ppm, lithium ion content: 0.3 ppm, chloride ion content: 0.075 ppm)

<Antioxidant C>
IRGANOX 1010 (manufactured by BASF Japan Ltd., lot number C1, cation content: 1.3 ppm, lithium ion content: 0.6 ppm, chloride ion content: 0.105 ppm)

<Antioxidant D>
ADK STAB AO-60 (manufactured by ADEKA Corporation, lot number D1, cation content: 1.9 ppm, lithium ion content: 1.4 ppm, chloride ion content: 0.117 ppm)

<Antioxidant E>
IRGANOX 1010 (manufactured by BASF Japan Ltd., lot number E1, cation content: 4.2 ppm, lithium ion content: 3.2 ppm, chloride ion content: 0.142 ppm)

[Example 1]
100 parts by mass of cyclic olefin resin and 0.2 part by mass of antioxidant A were blended. The above blend was kneaded at a predetermined temperature in a temperature range of 210 to 300 ° C. using a twin screw extruder (specification: diameter 25 mm, length: 26 D, T die width: 160 mm) with a die attached to the tip. Then, the cyclic olefin resin composition was extruded at a speed of 250 g / min, and a film having a thickness of 50 mm was wound on a roll. As shown in Table 1, the number of defects of the obtained film was 81/25 mm square. Moreover, retardation R0 of the obtained film was 0.4 nm, tear strength was 55 N / mm, and haze was 0.2%.

[Example 2]
Except for blending 90 parts by mass of cyclic olefin resin and 10 parts by mass of styrene elastomer, 0.2 parts by mass of antioxidant A in this blend, and kneading using a twin screw extruder. A film was produced in the same manner as in Example 1. As shown in Table 1, the number of defects of the obtained film was 81/25 mm square. Moreover, retardation R0 of the obtained film was 2.0 nm, tear strength was 90 N / mm, and haze was 1.4%.

[Example 3]
Except for blending 90 parts by mass of cyclic olefin resin and 10 parts by mass of styrene elastomer, 0.2 parts by mass of antioxidant B in this blend, and kneading using a twin screw extruder. A film was produced in the same manner as in Example 1. As shown in Table 1, the number of defects of the obtained film was 88 pieces / 25 mm square. Moreover, retardation R0 of the obtained film was 2.0 nm, tear strength was 90 N / mm, and haze was 1.4%.

[Comparative Example 1]
Except for blending 90 parts by mass of cyclic olefin resin and 10 parts by mass of styrene elastomer, 0.2 parts by mass of antioxidant C in this blend, and kneading using a twin screw extruder. A film was produced in the same manner as in Example 1. As shown in Table 1, the number of defects of the obtained film was 122/25 mm square. Moreover, retardation R0 of the obtained film was 2.0 nm, tear strength was 90 N / mm, and haze was 1.4%.

[Comparative Example 2]
Except for blending 90 parts by mass of cyclic olefin resin and 10 parts by mass of styrene elastomer, 0.2 parts by mass of antioxidant D in this blend, and kneading using a twin screw extruder. A film was produced in the same manner as in Example 1. As shown in Table 1, the number of defects of the obtained film was 129/25 mm square. Moreover, retardation R0 of the obtained film was 2.0 nm, tear strength was 90 N / mm, and haze was 1.4%.

[Comparative Example 3]
Except for blending 90 parts by mass of cyclic olefin resin and 10 parts by mass of styrene elastomer, 0.2 parts by mass of antioxidant E in this blend, and kneading using a twin screw extruder. A film was produced in the same manner as in Example 1. As shown in Table 1, the number of defects of the obtained film was 132 pieces / 25 mm square. Moreover, retardation R0 of the obtained film was 2.0 nm, tear strength was 90 N / mm, and haze was 1.4%.

  FIG. 1 is a graph showing the relationship between the content of lithium ions contained in the antioxidant and the number of defects. FIG. 2 is a graph showing the relationship between the content of cations contained in the antioxidant and the number of defects. FIG. 3 is a graph showing the relationship between the content of chloride ions contained in the antioxidant and the number of defects. As shown in FIGS. 1 to 3, it was found that the number of defects tends to increase in proportion to the lithium ion content, the cation content, or the chloride ion content.

  As in Examples 1 to 3, the antioxidant is an antioxidant having the above-mentioned conditions (1) to (3), that is, the content of lithium ions contained in the antioxidant is 0.4 ppm or less. Cyclic olefin-based resin composition film satisfying at least one of a cation content of 0.9 ppm or less and a chloride ion content of an antioxidant of 0.1 ppm or less Found that the defects were suppressed.

  In particular, it was found that defects were more effectively suppressed in the cyclic olefin-based resin composition film in which the antioxidant satisfies all the conditions (1) to (3) described above. Moreover, it turned out that the optical characteristics (retardation, haze) and toughness (tear strength) are more favorable for the cyclic olefin-type resin composition film containing a styrene-type elastomer like Example 2, 3. FIG.

On the other hand, as in Comparative Examples 1 to 3, the cyclic olefin-based resin composition film in which the antioxidant does not satisfy any of the conditions (1) to (3) described above is difficult to suppress defects. I understood.

Claims (7)

A cyclic olefin resin composition film containing a cyclic olefin resin and an antioxidant, wherein the antioxidant satisfies at least one of the following conditions (1) to (3).
(1) The content of lithium ions contained in the antioxidant is 0.4 ppm or less.
(2) The content of the cation contained in the antioxidant is 0.9 ppm or less.
(3) The content of chloride ions contained in the antioxidant is 0.1 ppm or less.   The cyclic olefin resin composition film according to claim 1, wherein the film satisfies at least the condition (1).   The cyclic olefin resin composition film according to claim 1, which satisfies at least the condition (3).   The cyclic olefin resin composition film according to claim 1, wherein all of the conditions (1) to (3) are satisfied.   The cyclic olefin-based resin composition film according to any one of claims 1 to 4, wherein the antioxidant is a phenol-based antioxidant.   The cyclic olefin resin composition film according to any one of claims 1 to 5, further comprising a styrene elastomer. The cyclic olefin resin composition film according to any one of claims 1 to 6, wherein the cyclic olefin resin is an addition copolymer of ethylene and norbornene.

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