Resin composition, film, polarizing sheet, and sunglasses

Abstract

To provide a resin composition capable of providing a film having excellent transparency and effectively suppressing roll contamination during film production, as well as to provide a film, a polarizing sheet, and sunglasses.SOLUTION: A resin composition comprises a polyamide resin containing an alicyclic diamine unit and an aliphatic dicarboxylic acid unit having 7 to 20 carbons, and a polyalkylene glycol, wherein the polyalkylene glycol contains an ethylene glycol unit and / or a propylene glycol unit at a total proportion of 50 mol% or more of all units, and has a number average molecular weight of 100 to 3500.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a resin composition, a film, a polarizing sheet, and sunglasses, and more particularly to a resin composition containing a polyamide resin as a main component. [Background technology]

[0002] Polyamide resins have excellent mechanical properties such as rigidity and strength, as well as heat resistance, and are therefore used in a wide range of applications, including electrical and electronic applications, automobiles, machinery, and building materials (Patent Documents 1 to 3). [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Laid-Open No. 2015-129271 [Patent Document 2] Japanese Patent Application Laid-Open No. 2013-001906 [Patent Document 3] Japanese Patent Application Laid-Open No. 2012-131977 Summary of the Invention [Problem to be solved by the invention]

[0004] As mentioned above, polyamide resins are used in a wide variety of fields, but they are generally poor in transparency and have not been used in applications where transparency is required. Under these circumstances, the present inventors have investigated the use of polyamide resins for transparent applications such as protective films for polarizing films, etc. However, when polyamide resins are molded into films, contamination of rolls may occur during film production. The present invention aims to solve these problems by providing a resin composition capable of providing a film that has excellent transparency and can effectively suppress roll contamination during film production, as well as a film, a polarizing sheet, and sunglasses. [Means for solving the problem]

[0005] In light of the above-mentioned problems, the present inventors have conducted research and found that the above-mentioned problems can be solved by blending a polyalkylene glycol containing ethylene glycol units and / or propylene glycol units in a total amount of 50 mol % or more of all units and having a number average molecular weight of 100 to 3500 with a specified polyamide resin. Specifically, the above problems were solved by the following means. <1> The composition comprises a polyamide resin containing an alicyclic diamine unit and an aliphatic dicarboxylic acid unit having 7 to 20 carbon atoms, and a polyalkylene glycol, The polyalkylene glycol contains ethylene glycol units and / or propylene glycol units in a total amount of 50 mol % or more of all units, and has a number average molecular weight of 100 to 3,500. <2> The aliphatic dicarboxylic acid unit having 7 to 20 carbon atoms includes a sebacic acid unit and / or a dodecanedioic acid unit. <1> The resin composition according to claim 1. <3> the alicyclic diamine constituting the alicyclic diamine unit contains two substituted or unsubstituted cyclohexane rings; <1> or <2> The resin composition according to claim 1. <4> The alicyclic diamine unit includes a unit represented by formula (PA-1): <1> or <2> The resin composition according to claim 1. [ka] (In formula (PA-1), R 1 are each independently an alkyl group having 1 to 5 carbon atoms, and each n1 is independently an integer of 0 to 3. * is a bonding site to another unit or a terminal group. <5> The content of polyalkylene glycol contained in the resin composition is 0.01 to 5% by mass. <1> ~ <4> The resin composition according to any one of the above. <6> the aliphatic dicarboxylic acid unit having 7 to 20 carbon atoms contains a sebacic acid unit and / or a dodecanedioic acid unit, the alicyclic diamine unit includes a unit represented by formula (PA-1), The content of polyalkylene glycol contained in the resin composition is 0.01 to 5% by mass. <1> ~ <5> The resin composition according to any one of the above. [ka] (In formula (PA-1), R 1 are each independently an alkyl group having 1 to 5 carbon atoms, and each n1 is independently an integer of 0 to 3. * is a bonding site to another unit or a terminal group. <7> The polyamide resin is an amorphous resin. <1> ~ <6> The resin composition according to any one of the above. <8> The haze of the resin composition when molded into a film with a thickness of 300 μm is 3.0% or less. <1> ~ <7> The resin composition according to any one of the above. <9> When the resin composition is molded into a film having a thickness of 300 μm, the total light transmittance is 80% or more. <1> ~ <8> The resin composition according to any one of the above. <10> It is used as a protective film for polarizing sheets. <1> ~ <9> The resin composition according to any one of the above. <11> <1> ~ <10> A film formed from the resin composition according to any one of the above. <12> <11> A polarizing sheet comprising the film according to claim 1 and a polarizing film. <13> <12> Sunglasses comprising the polarizing sheet according to claim 1. [Effects of the Invention]

[0006] It has become possible to provide a resin composition capable of providing a film that is excellent in transparency and can effectively prevent roll contamination during film production, as well as a film, a polarizing sheet, and sunglasses. [Brief explanation of the drawings]

[0007] [Figure 1] 1 is a schematic diagram illustrating an example of a layer structure of a hot-bent molded product according to an embodiment of the present invention. FIG. DETAILED DESCRIPTION OF THE INVENTION

[0008] Hereinafter, an embodiment for carrying out the present invention (hereinafter simply referred to as "the present embodiment") will be described in detail. Note that the present embodiment is an example for explaining the present invention, and the present invention is not limited to only this embodiment. In this specification, the symbol "to" is used to mean that the numerical values ​​before and after it are included as the upper and lower limits. Furthermore, any combination of the upper and lower limit values ​​of the numerical values ​​in this specification is an example of this embodiment. In this specification, various physical properties and characteristic values ​​are those at 23°C unless otherwise specified. In the description of groups (atomic groups) in this specification, when a notation does not specify whether they are substituted or unsubstituted, it includes both groups (atomic groups) that have no substituents and groups (atomic groups) that have substituents. For example, the term "alkyl group" includes not only alkyl groups that have no substituents (unsubstituted alkyl groups) but also alkyl groups that have substituents (substituted alkyl groups). In this specification, when a notation does not specify whether they are substituted or unsubstituted, it is preferable that they be unsubstituted. Examples of the substituent herein include, preferably, a halogen atom, a cyano group, a nitro group, a hydroxy group, an alkyl group, an alkoxy group, an aryl group, an aryloxy group, a heterocyclic group, a heterocyclic oxy group, an alkenyl group, an alkylsulfanyl group, an arylsulfanyl group, an acyl group, or an amino group; more preferably, a halogen atom, an alkyl group, an alkoxy group, an aryl group, an aryloxy group, an alkenyl group, or an acyl group; even more preferably, an alkyl group, an aryl group, an aryloxy group, or an alkenyl group; and even more preferably, an alkyl group. The formula weight of these substituents is preferably 15 or more and preferably 200 or less. For example, the formula weight of a methyl group (-CH3) is 15. These substituents may further have a substituent, but it is preferable that they have no substituent.

[0009] The term "film" as used herein refers to a generally flat molded product that is thin relative to its length and width, and includes sheets. The term "film" as used herein may be either a single layer or a multilayer, with a single layer being preferred. If the measurement methods, etc. described in the standards shown in this specification change from year to year, they will be based on the standards in effect as of January 1, 2024, unless otherwise specified. If the measurement methods, etc. described in the standards shown in this specification are abolished as of January 1, 2024, they will be based on the standards in effect at the time of abolition. The scale of Figure 1 may not be consistent with reality.

[0010] The resin composition of this embodiment comprises a polyamide resin containing alicyclic diamine units and aliphatic dicarboxylic acid units having 7 to 20 carbon atoms, and a polyalkylene glycol, wherein the polyalkylene glycol contains ethylene glycol units and / or propylene glycol units in a total proportion of 50 mol % or more of all units, and has a number average molecular weight of 100 to 3,500. By configuring in this way, a resin composition can be obtained that can provide a film that has excellent transparency and can effectively suppress roll contamination during film production. It is presumed that roll contamination occurs when, for example, the polyamide resin remains in the die during extrusion molding and adheres to the metal wall surface, resulting in decomposition of the polyamide resin. The inventors have conducted studies and found that by using a polyalkylene glycol containing ethylene glycol units and / or propylene glycol units in a total proportion of 50 mol % or more of all units and having a number-average molecular weight of 100 to 3500 as the polyalkylene glycol, it is possible to effectively suppress the polyamide resin from remaining in the die, thereby effectively suppressing roll contamination. This is presumably because the inclusion of ethylene glycol units and / or propylene glycol units in a total proportion of 50 mol % or more of all units allows for adequate compatibility with the polyamide resin, and the inclusion of polyalkylene glycol with a number-average molecular weight of 100 to 3500 makes it easier for the alkylene chains of the polyalkylene glycol to be present on the metal wall surface side within the die.The use of polyalkylene glycol with these characteristics is presumably responsible for the production of a resin composition that can provide a film that maintains transparency while effectively suppressing roll contamination during film production. The details of this embodiment will be described below.

[0011] <Polyamide resin containing alicyclic diamine units and aliphatic dicarboxylic acid units having 7 to 20 carbon atoms> The resin composition of the present embodiment contains a polyamide resin containing an alicyclic diamine unit and an aliphatic dicarboxylic acid unit having 7 to 20 carbon atoms (sometimes referred to as "polyamide resin (A)" in this specification). The alicyclic structure of the polyamide resin (A) improves the transparency of the polyamide resin itself, and the aliphatic dicarboxylic acid unit having 7 to 20 carbon atoms increases the compatibility with polyalkylene glycol, improving the transparency of the resulting resin composition.

[0012] In this embodiment, the alicyclic diamine constituting the alicyclic diamine unit is preferably a diamine containing a five-membered alicyclic ring and / or a six-membered alicyclic ring. The five-membered ring and / or the six-membered ring may or may not have a substituent. Furthermore, the alicyclic diamine is preferably composed only of an aliphatic hydrocarbon group containing an alicyclic structure, except for the terminal amino group. The alicyclic diamine unit more preferably contains two to three or more substituted or unsubstituted cyclohexane rings, and further preferably contains two substituted or unsubstituted cyclohexane rings, per unit. The alicyclic diamine unit preferably does not contain a carbon-carbon double bond or a carbon-carbon triple bond. The molecular weight of the alicyclic diamine constituting the alicyclic diamine unit is preferably 195 or more, more preferably 200 or more, and is preferably 500 or less, more preferably 400 or less, and even more preferably 300 or less.

[0013] In this embodiment, it is more preferable that the alicyclic diamine unit contains at least one type represented by formula (PA-0). [ka] (In formula (PA-0), each R is independently a substituent, each n is independently an integer of 0 to 5, L is a single bond or a divalent linking group, and * is a bonding site to another unit or a terminal group.) In formula (PA-0), each R is independently a substituent, and is preferably an aliphatic group having 1 to 6 carbon atoms, more preferably an alkyl group having 1 to 6 carbon atoms, even more preferably a linear or branched alkyl group having 1 to 6 carbon atoms, still more preferably a methyl group, an ethyl group, or a propyl group, and even more preferably a methyl group. In formula (PA-0), n's are each independently an integer of 0 to 5, preferably an integer of 1 or greater, and more preferably an integer of 4 or less, more preferably an integer of 3 or less, even more preferably an integer of 2 or less, and even more preferably an integer of 1 or less. In formula (PA-0), L represents a single bond or a divalent linking group, more preferably a single bond or a divalent aliphatic hydrocarbon group, more preferably a single bond or a divalent alkylene group, even more preferably a single bond or an alkylene group having 1 to 3 carbon atoms, still more preferably a single bond, a methylene group, an ethylene group, or an isopropylene group, and even more preferably a methylene group. * is a bonding site with another unit or a terminal group. That is, it is usually bonded to -C(=O)- to form an amide bond together with NH in formula (PA-0), or to a hydrogen atom to form a terminal amino group together with NH in formula (PA-0), or to a terminal group.

[0014] In this embodiment, the alicyclic diamine unit is more preferably represented by formula (PA-1). [ka] (In formula (PA-1), R 1 are each independently an alkyl group having 1 to 5 carbon atoms, and each n1 is independently an integer of 0 to 3. * is a bonding site to another unit or a terminal group.

[0015] In formula (PA-1), R 1 is an alkyl group having 1 to 5 carbon atoms, preferably a linear or branched alkyl group having 1 to 5 carbon atoms, more preferably a methyl group, an ethyl group or a propyl group, and even more preferably a methyl group. In formula (PA-1), n1 is an integer of 0 to 3, preferably an integer of 1 or more, and more preferably an integer of 2 or less, with 1 being more preferred.

[0016] Specific examples of the alicyclic diamine include 1,3-bis(aminomethyl)cyclohexane, 1,4-bis(aminomethyl)cyclohexane, 1,3-diaminocyclohexane, 1,4-diaminocyclohexane, bis(4-aminocyclohexyl)methane, bis(4-amino-3-methylcyclohexyl)methane, 2,2-bis(4-aminocyclohexyl)propane, 2,2-bis(4-amino-3-methylcyclohexyl)propane, bis(aminomethyl)decalin, and bis(aminomethyl)tricyclodecane.

[0017] The polyamide resin (A) contains alicyclic diamine units in a proportion of preferably 75 mol % or more, more preferably 80 mol % or more, even more preferably 85 mol % or more, still more preferably 90 mol % or more, still more preferably 95 mol % or more, particularly preferably 99 mol % or more, and 100 mol % or less of the diamine units constituting the polyamide resin (A). The alicyclic diamine units may be one type or a combination of two or more types.

[0018] Examples of diamines other than alicyclic diamines that can be used as the raw diamine component of the polyamide resin (A) include aliphatic diamines such as tetramethylenediamine, pentamethylenediamine, 2-methylpentanediamine, hexamethylenediamine, heptamethylenediamine, octamethylenediamine, nonamethylenediamine, decamethylenediamine, dodecamethylenediamine, 2,2,4-trimethyl-hexamethylenediamine, and 2,4,4-trimethylhexamethylenediamine, and diamines having an aromatic ring such as xylylenediamine, bis(4-aminophenyl)ether, paraphenylenediamine, and bis(aminomethyl)naphthalene, and these can be used alone or in combination of two or more.

[0019] On the other hand, in this embodiment, the aliphatic dicarboxylic acid having 7 to 20 carbon atoms constituting the aliphatic dicarboxylic acid unit having 7 to 20 carbon atoms is preferably a linear or branched aliphatic dicarboxylic acid having 7 to 20 carbon atoms, more preferably a linear aliphatic dicarboxylic acid having 7 to 20 carbon atoms, and even more preferably an α,ω-linear aliphatic dicarboxylic acid having 7 to 20 carbon atoms. The number of carbon atoms constituting the linear aliphatic dicarboxylic acid having 7 to 20 carbon atoms is preferably 8 or more, more preferably 9 or more, and even more preferably 10 or more, and is preferably 18 or less, more preferably 16 or less, even more preferably 14 or less, even more preferably 13 or less, and even more preferably 12 or less. The aliphatic dicarboxylic acid having 7 to 20 carbon atoms is preferably HOOC-(CH2) n It is preferably represented by —COOH, where n is an integer of 5 to 18. The aliphatic dicarboxylic acid unit having 7 to 20 carbon atoms that can be used in this embodiment preferably contains at least one of a sebacic acid unit, an undecanedioic acid unit, and a dodecanedioic acid unit, and more preferably contains a sebacic acid unit and / or a dodecanedioic acid unit.

[0020] The polyamide resin (A) contains aliphatic dicarboxylic acid units having 7 to 20 carbon atoms in a proportion of preferably 75 mol % or more, more preferably 80 mol % or more, even more preferably 85 mol % or more, still more preferably 90 mol % or more, still more preferably 95 mol % or more, particularly preferably 99 mol % or more, and 100 mol % or less, of the dicarboxylic acid units constituting the polyamide resin. The aliphatic dicarboxylic acid units having 7 to 20 carbon atoms may be one type, or two or more types may be combined.

[0021] Examples of dicarboxylic acid components other than the aliphatic dicarboxylic acids having 7 to 20 carbon atoms include phthalic acid compounds such as isophthalic acid, terephthalic acid, and orthophthalic acid, and isomers of naphthalenedicarboxylic acid such as 1,2-naphthalenedicarboxylic acid, 1,3-naphthalenedicarboxylic acid, 1,4-naphthalenedicarboxylic acid, 1,5-naphthalenedicarboxylic acid, 1,6-naphthalenedicarboxylic acid, 1,7-naphthalenedicarboxylic acid, 1,8-naphthalenedicarboxylic acid, 2,3-naphthalenedicarboxylic acid, 2,6-naphthalenedicarboxylic acid, and 2,7-naphthalenedicarboxylic acid, and these can be used alone or in combination of two or more.

[0022] The polyamide resin (A) used in this embodiment may further contain an aminocarboxylic acid unit, which tends to improve the color of the molded article. The type of aminocarboxylic acid constituting the aminocarboxylic acid unit is not particularly limited, and known aminocarboxylic acids can be used. The aminocarboxylic acid is preferably composed only of aliphatic hydrocarbon groups other than the terminal amino and carboxylic acid groups. The molecular weight of the aminocarboxylic acid constituting the aminocarboxylic acid unit is preferably 180 or more, more preferably 190 or more, and is preferably 400 or less, more preferably 300 or less, and even more preferably 250 or less.

[0023] The aminocarboxylic acid constituting the aminocarboxylic acid unit is preferably represented by formula (PA-2). [ka] (In formula (PA-2), n is an integer of 5 to 20.) In formula (PA-2), n is an integer of 5 to 20, preferably 6 or more, more preferably 7 or more, even more preferably 8 or more, still more preferably 9 or more, and even more preferably 10 or more, and preferably 18 or less, more preferably 16 or less, even more preferably 14 or less, still more preferably 13 or less, and even more preferably 12 or less.

[0024] The polyamide resin (A) contains diamine units and dicarboxylic acid units as main components, but does not completely exclude other monomer units, and may, of course, contain lactam units such as ε-caprolactam and laurolactam, and aliphatic aminocarboxylic acid units such as aminocaproic acid and aminoundecanoic acid. In particular, the polyamide resin (A) used in this embodiment preferably contains aminocarboxylic acid units. In this embodiment, among the monomer units constituting the polyamide resin (A), the total number of diamine units, dicarboxylic acid units, and optionally contained aminocarboxylic acid units preferably accounts for 90% by mass or more of all monomer units, more preferably 95% by mass or more, even more preferably 97% by mass or more, and even more preferably 99% by mass or more. The molar ratio of diamine units to dicarboxylic acid units in the polyamide resin (A) is preferably 40:60 to 60:40, and more preferably 45:55 to 55:45. In addition, in this embodiment, the proportion of aminocarboxylic acid units among all monomer units constituting the polyamide resin (A) is preferably 1 mol% or more, more preferably 5 mol% or more, and is preferably 50 mol% or less, more preferably 40 mol% or less.

[0025] The polyamide resin (A) is preferably an amorphous resin. An amorphous resin is a resin that does not have a clear melting point. Specifically, it refers to a resin having a crystalline fusion enthalpy ΔHm of less than 5 J / g, preferably 3 J / g or less, and more preferably 1 J / g or less. The crystalline fusion enthalpy ΔHm is measured in accordance with JIS K7121 and K7122 during the heating process. Specifically, the polyamide resin is measured using a differential scanning calorimeter (DSC) in a nitrogen stream by heating from room temperature to 250°C at a heating rate of 10°C / min, immediately cooling to below room temperature, and then heating again from room temperature to 250°C at a heating rate of 10°C / min.

[0026] It is also preferable to use polyamide resin (A) produced using biomass raw materials (biomass polyamide resin). Using biomass polyamide resin can reduce the environmental impact. Polyamide resin (A) can also be made from monomer raw materials that have been mass balance certified (ISCC PLUS). Mass balance certification means that the amount of renewable raw materials and bio-based raw materials used at each factory or production facility and the amount of products produced and shipped are quantified, and the quality is guaranteed. Furthermore, the polyamide resin (A) may be a recycled product (including recovered products, material recycled products, chemical recycled products, etc.), a rejected product, or scrap material generated during molding of the polyamide resin (A) or the resin composition of the present embodiment.

[0027] The content of polyamide resin (A) in the resin composition of this embodiment is preferably 90% by mass or more, more preferably 95% by mass or more, even more preferably 97% by mass or more, even more preferably 98% by mass or more, and even more preferably 99% by mass or more, based on 100% by mass of the resin composition. By making the content equal to or greater than the lower limit, the glass transition temperature tends to be higher. Furthermore, the content of polyamide resin (A) in the resin composition of this embodiment is preferably 99.999% by mass or less, based on 100% by mass of the resin composition. By making the content equal to or less than the upper limit, the transparency of the obtained film tends to be further improved. Furthermore, the resin composition of this embodiment may contain only polyamide resin (A) except for polyalkylene glycol (B). The resin composition of the present embodiment may contain only one type of polyamide resin (A), or may contain two or more types. When two or more types are contained, the total amount is preferably within the above range.

[0028] The resin composition of the present embodiment may or may not contain a polyamide resin other than the polyamide resin (A). Examples of polyamide resins other than the polyamide resin (A) include aliphatic polyamide resins other than the polyamide resin (A) and aromatic polyamide resins. Examples of aliphatic polyamide resins include polyamide 4, polyamide 46, polyamide 6, polyamide 66, polyamide 666, polyamide 610, polyamide 11, polyamide 116, polyamide 12, and polyamide 612. Examples of aromatic polyamide resins include polyhexamethylene terephthalamide (polyamide 6T), polyhexamethylene isophthalamide (polyamide 6I), polyamide 66 / 6T, polyamide 9T, polyamide 9MT, polyamide 10T, polyamide 6I / 6T, and xylylenediamine-based polyamide resins (such as MXD6).

[0029] It is also preferable to use, as the aliphatic polyamide resin and aromatic polyamide resin other than the polyamide resin (A), recycled resins or polyamide resins produced using biomass raw materials (biomass thermoplastic resins). Furthermore, the resin composition of this embodiment preferably does not substantially contain any polyamide resin other than the polyamide resin (A). Specifically, the content of polyamide resins other than the polyamide resin (A) contained in the resin composition of this embodiment is preferably less than 10% by mass, more preferably less than 5% by mass, even more preferably less than 3% by mass, even more preferably less than 1% by mass, and even more preferably less than 0.1% by mass, based on 100% by mass of the resin composition.

[0030] <Polyalkylene glycol> The resin composition of this embodiment contains a polyalkylene glycol (hereinafter sometimes referred to as "polyalkylene glycol (B)") that contains ethylene glycol units and / or propylene glycol units in a total proportion of 50 mol % or more of all units and has a number average molecular weight of 100 to 3500. By using such a polyalkylene glycol in combination with the polyamide resin (A), a resin composition can be obtained that can provide a film that is excellent in transparency and can effectively suppress roll contamination during film production.

[0031] In this embodiment, the polyalkylene glycol contains ethylene glycol units and / or propylene glycol units in a total amount of at least 50 mol%, preferably at least 60 mol%, more preferably at least 70 mol%, even more preferably at least 80 mol%, even more preferably at least 90 mol%, even more preferably at least 95 mol%, and particularly preferably at least 99 mol% of all units. Furthermore, all units other than the terminal groups may be ethylene glycol units and / or propylene glycol units. By ensuring that the amount is at or above the lower limit, the polyalkylene glycol is more likely to bleed out onto the resin surface during molding, improving the lubricity with the inner wall of the molding machine and suppressing retention, which tends to further improve the effect of suppressing roll contamination. On the other hand, by ensuring that the amount of ethylene glycol units and / or propylene glycol units in total is at or above 50 mol% of all units, the polyalkylene glycol is more appropriately compatible with the polyamide resin, effectively suppressing excessive bleeding of the polyalkylene glycol onto the resin surface during molding, and tends to effectively suppress roll contamination caused by the polyalkylene glycol itself.

[0032] The polyalkylene glycol used in this embodiment may contain other monomer units in addition to ethylene glycol units and propylene glycol units. The other monomer units are preferably alkylene glycol units other than ethylene glycol units and propylene glycol units. Examples of other alkylene glycol units include methylene glycol, butylene glycol, pentylene glycol, hexylene glycol, trimethylene glycol, tetramethylene glycol, pentamethylene glycol, neopentyl glycol, 3-methyltetramethylene glycol, and hexamethylene glycol.

[0033] The polyalkylene glycol used in this embodiment may be modified at its terminal with any substituent. The modification of the terminals may be carried out at only one terminal of the polyalkylene glycol or at both terminals. The optional substituents include a carboxyl group, a hydroxy group, an alkyl ether, an aryl ether, an aralkyl ether, a fatty acid ester, and an aryl ester.

[0034] The number-average molecular weight of the polyalkylene glycol used in this embodiment is 100 to 3500, with the lower limit preferably being 300 or more, more preferably 500 or more, even more preferably 800 or more, and even more preferably 1000 or more, and the upper limit preferably being 3000 or less, more preferably 2000 or less, and even more preferably 1500 or less. By setting the number-average molecular weight at or above the lower limit, volatilization of the polyalkylene glycol tends to be effectively suppressed. On the other hand, by setting the number-average molecular weight at or below the upper limit, deterioration in transparency tends to be more effectively suppressed. This is presumably because polyalkylene glycol is not completely compatible with polyamide resin, forming a sea-island structure. When the number-average molecular weight of the polyalkylene glycol is high, the island portions expand, increasing the refractive index difference and decreasing transparency. The number average molecular weight is measured in accordance with JIS K1577.

[0035] Specific examples of the polyalkylene glycol used in this embodiment include polyethylene glycol, polypropylene glycol, or a copolymer containing ethylene glycol units and / or propylene glycol units and other alkylene glycol units, with polyethylene glycol or propylene glycol being preferred, and polypropylene glycol being more preferred from the viewpoint of ease of production.

[0036] The polyalkylene glycol used in the present embodiment is not particularly limited, and may be produced by a known method, or may be a commercially available product, such as D-1000 (manufactured by NOF Corporation) or D-2000 (manufactured by NOF Corporation).

[0037] The content of polyalkylene glycol (B) in the resin composition of this embodiment is preferably 0.01% by mass or more, more preferably 0.05% by mass or more, even more preferably 0.1% by mass or more, and even more preferably 0.2% by mass or more, based on 100% by mass of the resin composition. Depending on the intended use, it may be 0.4% by mass or more, and is preferably 5% by mass or less, more preferably 3% by mass or less, even more preferably 2% by mass or less, even more preferably 1% by mass or less, and even more preferably 0.5% by mass or less. Depending on the intended use, it may be 0.3 parts by mass or less. By setting it to the lower limit or more, roll contamination during molding tends to be effectively suppressed. Meanwhile, by setting it to the upper limit or less, it tends to be more effectively suppressed decreases in glass transition temperature and toughness. In the resin composition of this embodiment, the total amount of the polyamide resin (A) and the polyalkylene glycol (B) does not exceed 100% by mass. The resin composition of the present embodiment may contain only one type of polyalkylene glycol (B), or may contain two or more types. When two or more types are contained, the total amount is preferably within the above range. Furthermore, it is preferable that the resin composition of this embodiment does not substantially contain polyalkylene glycols other than the polyalkylene glycol (B) (for example, having a number average molecular weight of less than 100 or more than 3500). Specifically, the content of polyalkylene glycols other than the polyalkylene glycol (B) contained in the resin composition of this embodiment is preferably less than 10 parts by mass, more preferably less than 5 parts by mass, even more preferably less than 3 parts by mass, even more preferably less than 1 part by mass, and even more preferably less than 0.1 parts by mass, relative to 100 parts by mass of the polyalkylene glycol (B).

[0038] <Other ingredients> The resin composition of the present embodiment may or may not contain components other than the polyamide resin (A) and the polyalkylene glycol (B). Examples of other components include a release agent, an ultraviolet absorber, an antioxidant, a heat stabilizer, a flame retardant, a flame retardant aid, a colorant, an antistatic agent, a fluorescent brightener, an antifogging agent, a flow improver, a plasticizer, a dispersant, an antibacterial agent, an antiblocking agent, an impact improver, a sliding improver, a hue improver, and an acid trapping agent. In addition, the resin composition of this embodiment may contain additives described in paragraphs 0047 to 0103 of International Publication No. 2021 / 241471 and additives described in paragraphs 0041 to 0056 of Japanese Patent Application Laid-Open No. 2023-61203, within the scope of the present invention, and the contents of these additives are incorporated herein by reference.

[0039] When other components are contained, the total content thereof is preferably 0.001 to 3 mass% of the resin composition, more preferably less than 2 mass%, even more preferably less than 1 mass%, even more preferably less than 0.5 mass%, even more preferably less than 0.1 mass%, and may be less than 0.01 mass%. The other component may be contained in only one kind or in two or more kinds. When two or more kinds of other components are contained, it is preferable that the total amount is in the above range.

[0040] <Physical properties of resin composition> The resin composition of the present embodiment preferably has excellent transparency. Specifically, the resin composition of this embodiment preferably has a total light transmittance of 80% or more, more preferably 85% or more, and even more preferably 90% or more when molded to a thickness of 300 μm. The upper limit of the total light transmittance is preferably 100%, but the required performance is also satisfied even if it is 99% or less. Furthermore, the resin composition of this embodiment, when molded to a thickness of 300 μm, preferably has a haze of 3.0% or less, more preferably 2.0% or less, even more preferably 1.5% or less, even more preferably 1.0% or less, still more preferably 0.7% or less, even more preferably 0.5% or less, still more preferably 0.4% or less, and even more preferably 0.3% or less, 0.28% or less, or 0.25% or less. The lower limit of the haze is preferably 0%, but the required performance is also satisfied even if it is 0.001% or more. The total light transmittance and haze are measured according to the description in the examples below.

[0041] <Method of manufacturing resin composition> As a method for producing the resin composition of the present embodiment, any method can be adopted. For example, it can be obtained by adding polyamide resin (A) and polyalkylene glycol (B) and melt-kneading them. More specifically, the polyamide resin (A), polyalkylene glycol (B), and other components added as needed are mixed using a mixing means such as a V-type blender to prepare a lump-blended product, which is then melt-kneaded in a vented extruder and pelletized.

[0042] <Film> The film of this embodiment is formed from the film of this embodiment. The thickness of the film of this embodiment is preferably 10 μm or more, more preferably 50 μm or more, and even more preferably 100 μm or more, and is preferably 1000 μm or less, more preferably 800 μm or less, even more preferably 700 μm or less, even more preferably 600 μm or less, and even more preferably 500 μm or less.

[0043] The film of the present embodiment preferably has excellent transparency. Specifically, the film of this embodiment preferably has a total light transmittance of 80% or more, more preferably 85% or more, and even more preferably 90% or more. The upper limit of the total light transmittance of the film is preferably 100%, but the required performance is also satisfied even if it is 99% or less. Furthermore, the haze of the film of this embodiment is preferably 3.0% or less, more preferably 2.0% or less, even more preferably 1.5% or less, even more preferably 1.0% or less, even more preferably 0.7% or less, even more preferably 0.5% or less, even more preferably 0.4% or less, and even more preferably 0.3% or less, 0.28% or less, or 0.25% or less. The lower limit of the haze of the film is preferably 0%, but the required performance is also satisfied even if it is 0.001% or more. The total light transmittance and haze are measured according to the description in the examples below.

[0044] <Wound body> The film of this embodiment can be wound around a core material to form a roll.

[0045] <Polarizing sheet> A film formed from the resin composition of this embodiment or the film of this embodiment is preferably used as a protective film for a polarizing sheet (a film that protects a polarizing film). In this embodiment, the polarizing sheet preferably includes the film of this embodiment and a polarizing film, and is a sheet laminated in this order: the polarizing film and the protective film. That is, the film of this embodiment is preferably used as at least one of the protective films of the polarizing sheet. The protective film is usually attached to the polarizing film via an adhesive. In this embodiment, the protective film on one side of the polarizing sheet may be the film of this embodiment or another protective film. The protective film on the other side of the polarizing sheet may be a known protective film for a polarizing sheet, and may be the same as the film of this embodiment. Known polarizing films can be used, and examples thereof include polyvinyl alcohol (PVA) films with iodine or a dichroic organic dye adsorbed or impregnated therein. The adhesive used to bond the film / protective film and the polarizing film of the present embodiment can be a known adhesive, and examples thereof include acrylic adhesives, urethane adhesives, epoxy adhesives, silicone adhesives, polyvinyl alcohol adhesives, etc. Among these, urethane adhesives are preferred. The thickness of the adhesive is usually 1 μm or more and usually 30 μm or less. Furthermore, the polarizing sheet of this embodiment may further include a masking film or the like on the outer side of the protective film.

[0046] In this embodiment, the polarizing sheet of this embodiment is preferably used for a heat-bent molded product that has been subjected to heat bending processing. When the film of this embodiment is used in a polarizing sheet, it may be provided on either side of a polarizing film, or on both sides. In the first mode, the film of this embodiment is disposed so as to be positioned on the convex side of the polarizing film after heat bending, for example, on the side of the protective film 4 in FIG. In the second mode, the film of this embodiment is disposed so as to be positioned on the concave side of the polarizing film after heat bending, for example, on the side of the protective film 3 in FIG. In the third embodiment, the film of this embodiment is positioned on both sides of the polarizing film, for example, both of the protective films 3 and 4 in FIG. 1 are the film of this embodiment. In FIG. 1, the lens 1, polarizing film 2, and protective films 3 and 4 are bent, but it goes without saying that this embodiment also includes polarizing sheets that are not bent. The protective film used in the polarizing sheet of this embodiment may be stretched or not. In the first embodiment, it is preferably stretched. In the second embodiment, it is preferably not stretched.

[0047] In this embodiment, the polarizing sheet is preferably used as a polarizing sheet for use in liquid crystal display devices, polarized lenses (sunglasses, ski goggles, prescription eyeglass lenses, camera viewfinder lenses), covers for various instruments, glass for automobiles, glass for trains, polarizing sheets for in-vehicle display panels and electronic device housings, etc., in-vehicle inner mirrors, silver mirrors for helmets, etc., and is particularly preferably used as sunglasses. [Example]

[0048] The present invention will be explained in more detail below with reference to examples. The materials, amounts used, ratios, processing details, processing procedures, etc. shown in the following examples can be appropriately changed without departing from the spirit of the present invention. Therefore, the scope of the present invention is not limited to the specific examples shown below. If the measuring instruments used in the examples are difficult to obtain due to discontinuation or the like, measurements can be made using other instruments with equivalent performance.

[0049] 1.Raw materials A1: G850, manufactured by Arkema, a polyamide resin synthesized from bis(4-amino-3-methylcyclohexyl)methane, sebacic acid, and aminoundecanoic acid (the ratio of aminoundecanoic acid is 17 mol% relative to 100 mol% of the raw material monomers), amorphous polyamide resin A2: XE4205, manufactured by EMS, a polyamide resin synthesized from bis(4-amino-3-methylcyclohexyl)methane and sebacic acid, amorphous polyamide resin

[0050] B1: Fujifilm Wako Pure Chemical Industries, Ltd., polyethylene glycol, number average molecular weight: 1000 [ka] B2: D-1000, manufactured by NOF Corporation, polypropylene glycol, number average molecular weight: 1000 [ka] B3: D-2000, manufactured by NOF Corporation, polypropylene glycol, number average molecular weight: 2000 [ka] B4: D-4000, manufactured by NOF Corporation, polypropylene glycol, number average molecular weight: 4000 [ka] B5: PB-700, manufactured by NOF Corporation, copolymer of butylene glycol units and propylene glycol units (propylene glycol units are less than 50 mol% of all units), number average molecular weight: 700 [ka]

[0051] 2. Examples 1 to 6 and Comparative Examples 1 to 4 <Manufacturing of resin pellets> The components were blended in a tumbler to obtain the compositions shown in Tables 1 and 2 below (contents in Tables 1 and 2 are shown in parts by mass), and the blend was then fed into the base of a twin-screw extruder (TEX30α, manufactured by The Japan Steel Works, Ltd.) and melt-kneaded at a cylinder temperature of 280°C to produce pellets for the Examples and Comparative Examples.

[0052] <Film manufacturing> The pellets obtained above were extruded into a molten state using a T-die melt extruder consisting of a vented twin-screw extruder (Toshiba Machine Co., Ltd., "TEM-26DS") with a screw nominal diameter of 28 mm and a screw L / D of 40 at a discharge rate of 15 kg / h and a screw rotation speed of 250 rpm. The extrusion was then pressed between a first roll and a second roll, and then cooled and solidified to produce a film. The cylinder temperature and die temperature were 280°C, and the first roll and second roll temperatures were 120°C. A film with a thickness of 300 μm was obtained. Details of the first and second rolls used are as follows. First roll: Toshiba Machine Co., Ltd., UM roll Dimensions: outer diameter 180mm x roll width 400mm Second roll: Toshiba Machine Co., Ltd., rigid metal roll (surface: chrome-treated) Dimensions: outer diameter 180mm x roll width 400mm

[0053] <Roll stains> To produce the film, 30 kg of raw material was consumed for the evaluation of Polyamide A1, and 90 kg for the evaluation of Polyamide A2. After that, the rolls were visually inspected and evaluated as follows: Evaluation was carried out by five experts, and the judgement was made by majority vote. A: No contamination of the roll was observed, or some contamination of the roll was observed but at a level that was acceptable for practical use. B: Roll contamination occurred, and it was beyond the practical level.

[0054] <Haze and total light transmittance measurements> Using a haze meter, the haze (%) and total light transmittance (%) of the 300 μm thick film obtained above were measured under conditions of a D65 light source and a 10° field of view. The haze meter used was "HM-150" manufactured by Murakami Color Research Laboratory.

[0055] [Table 1]

[0056] [Table 2]

[0057] As is clear from the results in Tables 1 and 2, in the present invention, roll contamination was effectively suppressed and a film with excellent transparency was obtained. In contrast, when no polyalkylene glycol was included (Comparative Examples 1 and 2), or when a polyalkylene glycol was included but a polyalkylene glycol other than the polyalkylene glycol specified in the present invention was used (Comparative Examples 3 and 4), the haze was high, the total light transmittance was reduced (Comparative Example 3), and roll contamination occurred (Comparative Examples 1, 2, and 4). [Explanation of symbols]

[0058] 1 lens 2. Polarizing film 3 Protective film 4 Protective Film

Claims

1. The composition comprises a polyamide resin containing an alicyclic diamine unit and an aliphatic dicarboxylic acid unit having 7 to 20 carbon atoms, and a polyalkylene glycol, The polyalkylene glycol is a resin composition containing ethylene glycol units and / or propylene glycol units in a total amount of 50 mol % or more of all units and having a number average molecular weight of 100 to 3500, the content of polyalkylene glycol contained in the resin composition is 0.01 to 5% by mass, A resin composition, wherein the content of the polyamide resin contained in the resin composition is 90 to 99.99% by mass.

2. 2. The resin composition according to claim 1, wherein the aliphatic dicarboxylic acid unit having 7 to 20 carbon atoms includes a sebacic acid unit and / or a dodecanedioic acid unit.

3. The resin composition according to claim 1 or 2, wherein the alicyclic diamine constituting the alicyclic diamine unit contains two substituted or unsubstituted cyclohexane rings.

4. The resin composition according to claim 1 or 2, wherein the alicyclic diamine unit includes a unit represented by formula (PA-1): 【Chemical 1】 (In formula (PA-1), R １ are each independently an alkyl group having 1 to 5 carbon atoms, and each n1 is independently an integer of 0 to 3. * is a bonding site with another unit or a terminal group.

5. The resin composition according to claim 1 or 2, wherein the polyamide resin is an amorphous resin.

6. 3. The resin composition according to claim 1, wherein the resin composition has a haze of 3.0% or less when molded into a film having a thickness of 300 μm.

7. 3. The resin composition according to claim 1, wherein the resin composition has a total light transmittance of 80% or more when molded into a film having a thickness of 300 μm.

8. The aliphatic dicarboxylic acid unit having 7 to 20 carbon atoms includes a sebacic acid unit and / or a dodecanedioic acid unit, the alicyclic diamine unit contains a unit represented by formula (PA-1), the polyamide resin is an amorphous resin, The resin composition has a haze of 3.0% or less when molded into a film with a thickness of 300 μm, 2. The resin composition according to claim 1, wherein the resin composition has a total light transmittance of 80% or more when molded into a film having a thickness of 300 μm. 【Chemistry 2】 (In formula (PA-1), each R 1 is independently an alkyl group having 1 to 5 carbon atoms, and each n1 is independently an integer of 0 to 3. * denotes a bonding site with another unit or a terminal group.)

9. The resin composition according to claim 1 , which is used as a protective film for a polarizing sheet.

10. A film formed from the resin composition according to claim 1, 2 or 8.

11. A polarizing sheet comprising the film according to claim 10 and a polarizing film.

12. Sunglasses comprising the polarizing sheet according to claim 11.

Images