Resin composition, film, polarizing sheet, and sunglasses

Abstract

Provided are a resin composition, a film, a polarizing sheet, and sunglasses. The resin composition contains: a polyamide resin containing an alicyclic diamine unit, a C7-20 aliphatic dicarboxylic acid unit, and an amino carboxylic acid unit; and a polyether amide elastomer.

Description

Resin composition, film, polarizing sheet, and sunglasses

[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.

[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).

[0003] JP 2015-129271 A JP 2013-001906 A JP 2012-131977 A

[0004] As described above, polyamide resins are used in a wide variety of fields, but they generally have poor transparency and have not been used in applications requiring transparency. Under these circumstances, the present inventors investigated the use of polyamide resins in transparent applications such as protective films for polarizing films. However, they found that when polyamide resins are molded into films, roll contamination occurs during film production. The present invention aims to solve this problem 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.

[0005] In light of the above-mentioned problems, it has been found that the above problems can be solved by using a predetermined polyamide resin and a polyetheramide elastomer. Specifically, the above problems have been solved by the following means. <1> A resin composition comprising a polyamide resin containing alicyclic diamine units, aliphatic dicarboxylic acid units having 7 to 20 carbon atoms, and aminocarboxylic acid units, and a polyetheramide elastomer. <2> The resin composition according to <1>, in which the aliphatic dicarboxylic acid units having 7 to 20 carbon atoms include sebacic acid units and / or dodecanedioic acid units. <3> The resin composition according to <1> or <2>, in which the alicyclic diamine constituting the alicyclic diamine units includes two substituted or unsubstituted cyclohexane rings. <4> The resin composition according to <1> or <2>, in which the alicyclic diamine units include units represented by formula (PA-1). (In formula (PA-1), R １are 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 an end group.) <5> The resin composition according to any one of <1> to <4>, wherein the polyetheramide elastomer includes a polyalkylene glycol block and a polyamide block. <6> The resin composition according to <5>, wherein the polyalkylene glycol block includes a polypropylene glycol (PPG) block and / or a polytetramethylene ether glycol (PTMG) block. <7> The resin composition according to any one of <1> to <6>, wherein the content of the polyamide resin in the resin composition is 80.0 to 99.9 mass% and the content of the polyetheramide elastomer is 20.0 to 0.1 mass%. <8> The resin composition according to any one of <1> to <7>, wherein the aliphatic dicarboxylic acid units having 7 to 20 carbon atoms include sebacic acid units and / or dodecanedioic acid units, the alicyclic diamine units include units represented by formula (PA-1), the polyetheramide elastomer includes a polyalkylene glycol block and a polyamide block, and the polyalkylene glycol block includes a polypropylene glycol (PPG) block and / or a polytetramethylene ether glycol (PTMG) block, and the content of the polyamide resin in the resin composition is 80.0 to 99.9 mass%, and the content of the polyetheramide elastomer is 20.0 to 0.1 mass%. (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.) <9> The resin composition according to any one of <1> to <8>, wherein the aminocarboxylic acid constituting the aminocarboxylic acid unit is represented by formula (PA-2). (In formula (PA-2), n is an integer of 5 to 20.) <10> The resin composition according to any one of <1> to <9>, wherein the polyamide resin is an amorphous resin. <11> The resin composition according to any one of <1> to <10>, wherein the resin composition has a haze of 3.0% or less when molded into a film with a thickness of 300 μm. <12> The resin composition according to any one of <1> to <11>, wherein the resin composition has a total light transmittance of 80% or more when molded into a film with a thickness of 300 μm. <13> The resin composition according to any one of <1> to <12>, wherein the resin composition is used for a protective film for a polarizing sheet. <14> A film formed from the resin composition according to any one of <1> to <13>. <15> A polarizing sheet comprising the film according to <14> and a polarizing film. <16> Sunglasses comprising the polarizing sheet according to <15>.

[0006] The present invention makes it possible to provide a resin composition capable of providing a film that is excellent in transparency and can effectively suppress roll contamination during film production, as well as a film, a polarizing sheet, and sunglasses.

[0007] FIG. 2 is a schematic diagram illustrating an example of a layer structure of the heat-bent molded body of the present embodiment.

[0008] Hereinafter, a detailed description will be given of an embodiment of the present invention (hereinafter simply referred to as "the present embodiment"). Note that the following present embodiment is an example for explaining the present invention, and the present invention is not limited to this embodiment. In this specification, the term "to" is used to mean that the numerical values ​​before and after it are included as lower and upper limits. In this specification, various physical property values ​​and characteristic values ​​are those at 23°C unless otherwise specified. In the description of a group (atomic group), a notation that does not indicate substituted or unsubstituted encompasses both a group (atomic group) that has no substituent and a group (atomic group) that has a substituent. For example, the term "alkyl group" encompasses not only an alkyl group that has no substituent (unsubstituted alkyl group) but also an alkyl group that has a substituent (substituted alkyl group). In this specification, when a notation that does not indicate substituted or unsubstituted is used, unsubstituted is preferred. Examples of the substituent herein are 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 heterocyclicoxy 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 still more preferably an alkyl group. The formula weight of these substituents is preferably 15 or more, and preferably 200 or less. The formula weight is, for example, ３ ) is 15. These substituents may further have a substituent, but it is preferable that they have no substituent.

[0009] In this specification, the term "film" refers to a generally flat molded body that is thin relative to its length and width, and is intended to include sheets. The term "film" in this specification may be either single-layer or multi-layer, but single-layer is preferred. If the measurement methods and other aspects described in the standards set forth in this specification vary from year to year, they are based on the standards as of January 1, 2023, unless otherwise specified. The scale of Figure 1 may not be consistent with reality.

[0010] The resin composition of this embodiment is characterized by including a polyamide resin containing an alicyclic diamine unit, an aliphatic dicarboxylic acid unit having 7 to 20 carbon atoms, and an aminocarboxylic acid unit, and a polyetheramide elastomer. This configuration results in a resin composition that can provide a film that is excellent in transparency and can effectively suppress roll contamination during film production. The inclusion of an alicyclic diamine unit in the polyamide resin results in a resin composition with excellent transparency. On the other hand, polyamide resins, particularly decomposition products of polyamide resins, tend to adhere easily to metals and are prone to causing roll contamination during film production. In the polyamide resin used in this embodiment, components derived from the aliphatic dicarboxylic acid unit having 7 to 20 carbon atoms and the aminocarboxylic acid unit are likely to adhere to the roll. It is presumed that the incorporation of a polyetheramide elastomer in this embodiment effectively suppresses the adhesion of components derived from the aliphatic dicarboxylic acid unit having 7 to 20 carbon atoms and the aminocarboxylic acid unit to the roll during film production. Furthermore, in this embodiment, the aliphatic dicarboxylic acid unit having 7 to 20 carbon atoms contained in the polyamide resin and the polyetheramide elastomer (particularly, the polyalkylene glycol block) are compatible with each other, so that transparency can be maintained at a high level.

[0011] <Polyamide Resin Comprising Alicyclic Diamine Units, Aliphatic Dicarboxylic Acid Units Having 7 to 20 Carbon Atoms, and Aminocarboxylic Acid Units> The resin composition of the present embodiment comprises a polyamide resin (sometimes referred to as “polyamide resin (A)” in this specification) comprising alicyclic diamine units, aliphatic dicarboxylic acid units having 7 to 20 carbon atoms, and aminocarboxylic acid units.

[0012] In this embodiment, the alicyclic diamine constituting the alicyclic diamine unit is preferably a diamine containing a 5-membered alicyclic ring and / or a 6-membered alicyclic ring. The 5-membered ring and / or the 6-membered ring may or may not have a substituent. The alicyclic diamine more preferably contains two substituted or unsubstituted cyclohexane rings. The alicyclic diamine unit preferably does not contain a carbon-carbon double bond or a carbon-carbon triple bond. Furthermore, the alicyclic diamine is preferably composed only of aliphatic hydrocarbon groups containing an alicyclic structure, other than the terminal amino groups. The molecular weight of the alicyclic diamine constituting the alicyclic diamine unit is preferably 195 or more, more preferably 200 or more, and preferably 500 or less, more preferably 400 or less, and even more preferably 300 or less. In this embodiment, the alicyclic diamine unit is more preferably represented by formula (PA-0). (In formula (PA-0), each R is independently a substituent, and each n is independently an integer of 0 to 5. L is a single bond or a divalent linking group. * is a bonding site with 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, even more preferably a methyl group, ethyl group, or propyl group, and even more preferably a methyl group. In formula (PA-0), each n is independently an integer of 0 to 5, and is preferably an integer of 1 or greater, and is 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, still 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 still more preferably a methylene group. * represents a bonding site with another unit or a terminal group. That is, typically, L is bonded to -C(=O)- to form an amide bond together with NH in formula (PA-0), or is bonded to a hydrogen atom to form a terminal amino group together with NH in formula (PA-0), or is bonded to a terminal group.

[0013] In this embodiment, the alicyclic diamine unit more preferably contains a unit represented by formula (PA-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.

[0014] In formula (PA-1), R １is 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 preferably an integer of 2 or less.

[0015] 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.

[0016] The polyamide resin (A) contains alicyclic diamine units (preferably units represented by formula (PA-1)) 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 two or more types may be combined.

[0017] 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. These can be used alone or in combination of two or more.

[0018] 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-(CH ２ ) 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.

[0019] 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 (A). The aliphatic dicarboxylic acid units having 7 to 20 carbon atoms may be one type, or two or more types may be combined.

[0020] 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.

[0021] In this embodiment, 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, except for the terminal amino group and carboxylic acid group. 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.

[0022] In this embodiment, the aminocarboxylic acid constituting the aminocarboxylic acid unit is preferably represented by formula (PA-2). (In formula (PA-2), n is an integer of 5 to 20.) In formula (PA-2), n is an integer of 5 to 20, and is 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 is 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.

[0023] Although the polyamide resin (A) contains diamine units, dicarboxylic acid units, and aminocarboxylic acid units, other monomer units are not completely excluded, and it goes without saying that it may contain lactam units such as ε-caprolactam and laurolactam. In this embodiment, among the monomer units constituting the polyamide resin (A), the total amount of diamine units, dicarboxylic acid units, and aminocarboxylic acid units preferably accounts for 90% by mass or more of the total 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. In the polyamide resin (A), the molar ratio of diamine units to dicarboxylic acid units is preferably 40:60 to 60:40, and more preferably 45:55 to 55:45. Furthermore, in this embodiment, the proportion of aminocarboxylic acid units among all the monomer units constituting the polyamide resin (A) is preferably 1 mol% or more, more preferably 5 mol% or more, and preferably 50 mol% or less, and more preferably 40 mol% or less.

[0024] The polyamide resin (A) is preferably an amorphous resin. An amorphous resin is a resin that does not have a clear melting point. Specifically, the crystalline melting enthalpy ΔHm is less than 5 J / g, preferably 3 J / g or less, and more preferably 1 J / g or less. The crystalline melting 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.

[0025] It is also preferable to use a polyamide resin (biomass polyamide resin) produced using biomass raw materials as the polyamide resin (A). The use of a biomass polyamide resin can reduce the environmental impact. The polyamide resin (A) can also be a polyamide resin produced using mass balance certified (ISCC PLUS) monomer raw materials. Mass balance certification means that the amount of renewable raw materials or biomaterials used in each factory or production facility and the amount of products produced or shipped are quantified and guaranteed along with the quality. 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 this embodiment.

[0026] The content of polyamide resin (A) in the resin composition of this embodiment is preferably 80.0% by mass or more, more preferably 85.0% by mass or more, even more preferably 87.0% by mass or more, even more preferably 90.0% by mass or more, even more preferably 93.0% by mass or more, and even more preferably 94.0% by mass or more, based on 100% by mass of the resin composition. By setting the content to be equal to or greater than the lower limit, the glass transition temperature of the resulting film tends to be higher. Furthermore, the content of polyamide resin (A) in the resin composition of this embodiment is preferably 99.9% by mass or less, more preferably 99.5% by mass or less, based on 100% by mass of the resin composition. By setting the content to be equal to or less than the upper limit, the impact strength of the resulting film tends to be improved. The resin composition of this 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.

[0027] The resin composition of this 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 (e.g., MXD6).

[0028] It is also preferable to use a polyamide resin (biomass thermoplastic resin) produced using recycled resin or biomass raw material as the aliphatic polyamide resin and aromatic polyamide resin. Furthermore, it is preferable that the resin composition of this embodiment substantially does not 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.

[0029] <Polyetheramide elastomer> The resin composition of this embodiment contains a polyetheramide elastomer. By including a polyetheramide elastomer, roll contamination during film production can be effectively suppressed. Furthermore, haze can also be reduced. A polyetheramide elastomer is an elastomer containing a polyether structure and a polyamide structure. The polyetheramide elastomer of this embodiment is substantially free of an ester structure. "Substantially free of an ester structure" means that the polyetheramide elastomer is not a polyester etheramide elastomer. More specifically, the content of the ester structure is typically less than 1% by mass of the polyetheramide elastomer, preferably less than 0.5% by mass, more preferably less than 0.1% by mass, and even more preferably less than 0.01% by mass. The polyetheramide elastomer used in this embodiment preferably contains a polyalkylene glycol block and a polyamide block.

[0030] The polyalkylene glycol block is -(alkylene group -O) ｎ２ It is preferable that the -(alkylene group -O) is represented by -. ｎ２The alkylene group in - is preferably a linear or branched alkylene group having 1 to 10 carbon atoms. The number of carbon atoms constituting the alkylene group is preferably 2 or more, more preferably 3 or more, and is preferably 8 or less, more preferably 6 or less, even more preferably 5 or less, and still more preferably 4 or less. Specific examples of the -(alkylene group -O)- include -(CH ２ O)-, -(CH ２ CH ２ O)-, -(CH ２ CH ２ CH ２ O)-,-(CH(CH ３ ) CH ２ O)-, -(CH ２ CH ２ CH ２ CH ２ O)-,-(C(CH ３ ) ２ CH ２ Examples of the -(alkylene group -O) include -, and a combination of two or more of these is also acceptable. ｎ２ In the formula, n2 is preferably 1 to 200, and more preferably 3 to 100. The polyalkylene glycol block preferably contains a polypropylene glycol (PPG) block and / or a polytetramethylene ether glycol (PTMG) block.

[0031] The proportion of polyalkylene glycol blocks in the polyetheramide elastomer used in this embodiment is preferably 5 mol% or more, more preferably 10 mol% or more, even more preferably 15 mol% or more, and even more preferably 20 mol% or more, relative to 100 mol% of all structural units of the polyetheramide elastomer. Depending on the application, it may be 30 mol% or more, 40 mol% or more, 50 mol% or more, 60 mol% or more, or 65 mol% or more. By making the proportion equal to or greater than the lower limit, impact strength tends to be further improved when added to polyamide resin (A) (preferably an amorphous polyamide resin). Furthermore, the proportion of polyalkylene glycol blocks in the polyetheramide elastomer used in this embodiment is preferably 90 mol% or less, more preferably 85 mol% or less, even more preferably 80 mol% or less, and even more preferably 75 mol% or less, relative to 100 mol% of all structural units of the polyetheramide elastomer. By making the proportion equal to or less than the upper limit, compatibility with polyamide resin (A) (preferably an amorphous polyamide resin) tends to be improved. The polyetheramide elastomer may contain only one type of polyalkylene glycol block, or may contain two or more types. When two or more types are contained, the total amount is preferably within the above range.

[0032] The polyamide block is preferably represented by an aliphatic polyamide block, -(NH(CH ２ ) ｎ３ C(=O) ｎ４Preferably, the aliphatic polyamide block is represented by the formula: n3. Here, n3 is preferably 3 or more, more preferably 5 or more, even more preferably 7 or more, even more preferably 9 or more, and even more preferably 10 or more, and is preferably 20 or less, more preferably 18 or less, even more preferably 16 or less, even more preferably 14 or less, and even more preferably 12 or less. Furthermore, when n5 is the number of carbon atoms in the aliphatic dicarboxylic acid having 7 to 20 carbon atoms that constitutes polyamide resin (A) (for example, sebacic acid has n5 = 10), it is preferable that the difference (absolute value) between n5 and n3 is small. More specifically, |n5 - n3| is preferably 3 or less, and more preferably 2 or less. n4 is preferably 1 to 300, and more preferably 5 to 100.

[0033] The proportion of polyamide blocks in the polyetheramide elastomer used in this embodiment is preferably 10 mol% or more, more preferably 15 mol% or more, even more preferably 20 mol% or more, and even more preferably 25 mol% or more, relative to 100 mol% of all structural units of the polyetheramide elastomer. By ensuring that the proportion is above the lower limit, compatibility with polyamide resin (A) (preferably an amorphous polyamide resin) tends to be further improved. Furthermore, the proportion of polyamide blocks in the polyetheramide elastomer used in this embodiment is preferably 95 mol% or less, more preferably 90 mol% or less, even more preferably 85 mol% or less, and even more preferably 80 mol% or less, relative to 100 mol% of all structural units of the polyetheramide elastomer. Depending on the application, it may be 70 mol% or less, 60 mol% or less, 50 mol% or less, 40 mol% or less, or 35 mol% or less. By ensuring that the proportion is below the upper limit, a decrease in the glass transition temperature when added to polyamide resin (A) (preferably an amorphous polyamide resin) tends to be further suppressed. The polyetheramide elastomer may contain only one type of polyamide block or two or more types. When two or more types are contained, the total amount is preferably within the above range.

[0034] The weight average molecular weight of the polyetheramide elastomer used in this embodiment is preferably 3,000 or more, more preferably 5,000 or more, and preferably 100,000 or less, more preferably 80,000 or less. By making the weight average molecular weight equal to or greater than the lower limit, toughness tends to be improved when mixed with polyamide resin (A). By making the weight average molecular weight equal to or less than the upper limit, compatibility with polyamide resin (A) tends to be further improved. The weight average molecular weight is an acrylic equivalent value measured by GPC (gel permeation chromatography) method.

[0035] In the polyetheramide elastomer used in the present embodiment, the total of the polyalkylene glycol blocks and the polyamide blocks preferably accounts for 90% by mass or more, more preferably 95% by mass or more, and even more preferably 97% by mass or more, and is preferably 100% by mass or less, based on 100% by mass of the polyetheramide elastomer.

[0036] The content of the polyetheramide elastomer in the resin composition of this embodiment is preferably 0.1% by mass or more, more preferably 0.5% by mass or more, even more preferably 1.0% by mass or more, and even more preferably 1.5% by mass or more, relative to 100% by mass of the resin composition. From the viewpoint of more effectively suppressing roll contamination, it is even more preferably 2.0% by mass or more, and even more preferably 3.0% by mass or more. Furthermore, the content of the polyetheramide elastomer in the resin composition of this embodiment is preferably 20.0% by mass or less, more preferably 15.0% by mass or less, even more preferably 10.0% by mass or less, even more preferably 8.0% by mass or less, even more preferably 7.0% by mass or less, and even more preferably 5.0% by mass or less, relative to 100% by mass of the resin composition. From the viewpoint of further improving transparency, it is even more preferably 3.0% by mass or less, and particularly preferably 2.0% by mass or less. The resin composition of this embodiment may contain only one type of polyetheramide elastomer, or may contain two or more types of polyetheramide elastomer. When two or more types are contained, the total amount is preferably within the above range.

[0037] In the resin composition of this embodiment, the content of the polyamide resin (A) in the resin composition is preferably 80.0 to 99.9 mass %, and the content of the polyetheramide elastomer is preferably 20.0 to 0.1 mass %.

[0038] In the resin composition of the present embodiment, the total of the polyamide resin (A) and the polyetheramide elastomer preferably accounts for 90% by mass or more, more preferably 95% by mass or more, even more preferably 97% by mass or more, and even more preferably 99% by mass or more, based on 100% by mass of the resin composition, and is preferably 100% by mass or less.

[0039] <Other Components> The resin composition of this embodiment may or may not contain components other than the polyamide resin (A) and the polyetheramide elastomer. Examples of other components include ultraviolet absorbers, antioxidants, heat stabilizers, flame retardants, flame retardant aids, colorants, antistatic agents, fluorescent brighteners, antifogging agents, flow improvers, plasticizers, dispersants, antibacterial agents, antiblocking agents, impact improvers, sliding improvers, hue improvers, acid trapping agents, and the like. In addition, the resin composition of this embodiment may contain additives described in paragraphs 0047 to 0102 of WO 2021 / 241471 and additives described in paragraphs 0041 to 0049 of JP 2023-61203 A, within the scope of the present invention, and the contents of these additives are incorporated herein.

[0040] 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 even be less than 0.01 mass%. Only one type of other component may be contained, or two or more types may be contained. When two or more types of other components are contained, the total amount is preferably in the above range.

[0041] <Physical Properties of Resin Composition> The resin composition of this embodiment preferably has excellent transparency. Specifically, the resin composition of this embodiment, when molded into a 300 μm thick film, 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 is preferably 100%, but the required performance is met even if it is 99% or less. Furthermore, the resin composition of this embodiment, when molded into a 300 μm thick film, preferably has a haze of 3.0% or less, more preferably 2.5% or less, even more preferably 2.0% or less, even more preferably 1.5% or less, even more preferably 1.2% or less, and even more preferably 1.0% or less. The lower limit of the haze is preferably 0%, but the required performance is met even if it is 0.001% or more. The total light transmittance and haze are measured according to the description in the examples below.

[0042] <Method for Producing Resin Composition> Any method can be used to produce the resin composition of this embodiment. For example, the resin composition can be obtained by adding polyamide resin (A) and polyetheramide elastomer and melt-kneading them. More specifically, the polyamide resin (A), polyetheramide elastomer, and other components that are added as needed are mixed using a mixing means such as a V-type blender to prepare a lump blend, which is then melt-kneaded in a vented extruder and pelletized.

[0043] <Film> The film of this embodiment is formed from the resin composition 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.

[0044] The film of this 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 met even if it is 99% or less. Furthermore, the film of this embodiment preferably has a haze of 3.0% or less, more preferably 2.5% or less, even more preferably 2.0% or less, even more preferably 1.5% or less, even more preferably 1.2% or less, and even more preferably 1.0% or less. The lower limit of the haze is preferably 0%, but the required performance is met even if it is 0.001% or more. The total light transmittance and haze are measured according to the description in the examples below.

[0045] <Rolled Body> The film of the present embodiment can be wound around a core material to form a rolled body.

[0046] <Polarizing Sheet> A film formed from the resin composition of this embodiment or a 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, with the polarizing film and the protective film laminated in this order. That is, the film of this embodiment is preferably used as at least one of the protective films for a 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. The polarizing film may be a known polarizing film, and an example thereof is a polyvinyl alcohol (PVA) film adsorbed or impregnated with iodine or a dichroic organic dye. The adhesive used to attach the film or protective film of this embodiment to the polarizing film may be a known adhesive, such as an acrylic adhesive, a urethane adhesive, an epoxy adhesive, a silicone adhesive, or a polyvinyl alcohol adhesive. Among these, a urethane adhesive is 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 have a masking film or the like provided on the outer side of the protective film.

[0047] In this embodiment, the polarizing sheet of this embodiment is preferably used in a heat-bent article that has been subjected to heat bending. When the film of this embodiment is used in a polarizing sheet, it may be provided on either side of the polarizing film, or on both sides. In a first embodiment, the film of this embodiment is disposed so that it is positioned on the concave side of the polarizing film after heat bending, for example, on the side of protective film 4 in FIG. 1 . In a second embodiment, the film of this embodiment is disposed so that it is positioned on the convex side of the polarizing film after heat bending, for example, on the side of protective film 3 in FIG. 1 . In a third embodiment, the film of this embodiment is disposed on both sides of the polarizing film, for example, both protective films 3 and 4 in FIG. 1 are films of this embodiment. Note that in FIG. 1 , the lens 1, polarizing film 2, and protective films 3 and 4 of the polarizing sheet are bent, but it goes without saying that a case in which no bending is performed is also included in this embodiment. The protective film used in the polarizing sheet of this embodiment may or may not be stretched. In the first embodiment, it is preferably stretched. In the second embodiment, it is preferably unstretched.

[0048] In this embodiment, the polarizing sheet is preferably used as a polarizing sheet for use in liquid crystal display devices, polarizing 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.

[0049] The present invention will be explained in more detail below with reference to examples. The materials, amounts used, ratios, treatment contents, treatment procedures, etc. shown in the following examples can be changed as appropriate 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.

[0050] 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 proportion of aminoundecanoic acid is 17 mol%); amorphous polyamide resin. B1: 9040X1, a polyetheramide elastomer composed of 19 mol% polyamide 12 blocks, 50 mol% PTMG blocks, and 31 mol% PPG blocks; manufactured by UBE. B2: 9048X1, a polyetheramide elastomer composed of 30 mol% polyamide 12 blocks, 43 mol% PTMG blocks, and 27 mol% PPG blocks; manufactured by UBE. B3: PA-50M, a polymerized fatty acid polyamide resin; manufactured by T&K TOKA.

[0051] 2. Examples 1 and 2, Comparative Examples 1 and 2 <Production of Resin Composition Pellets> Each component was blended in a tumbler to obtain the composition shown in Table 1 below (contents in Table 1 are shown in parts by mass), and the blend was introduced 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 Production> The pellets obtained above were extruded into a molten state using a T-die melt extruder consisting of a vented twin-screw extruder (manufactured by The Japan Steel Works, Ltd., "TEX30α") ​​with a barrel diameter of 32 mm and a screw L / D of 31.5 at a discharge rate of 15 kg / h and a screw rotation speed of 250 rpm, followed by cooling and solidification to produce a film. The cylinder temperature was 280°C and the roll temperature was 120°C. A film with a thickness of 300 μm was obtained.

[0053] <Roll Contamination> After 30 kg of raw materials were consumed to produce a film, the roll was visually evaluated as follows. The evaluation was based on a majority vote of five experts, with Example 1 being given a rating of "B." A: No roll contamination was observed. B: Some roll contamination was observed, but at a practically acceptable level. C: Roll contamination occurred, and the level was beyond the practically acceptable level.

[0054] <Measurement of Haze and Total Light Transmittance> 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 Co., Ltd.

[0055]

[0056] In Table 1, B3 is a polymerized fatty acid polyamide resin, not a polyetheramide elastomer. As is clear from the results, the films formed from the resin compositions of the present invention have excellent transparency and effectively suppress roll contamination during production. In contrast, when only polyamide resin (A) was used (Comparative Example 1) or when a substitute for polyetheramide elastomer was used (Comparative Example 2), roll contamination occurred during film production.

[0057] 1 Lens 2 Polarizing film 3 Protective film 4 Protective film

Claims

1. A resin composition comprising a polyamide resin containing an alicyclic diamine unit, an aliphatic dicarboxylic acid unit having 7 to 20 carbon atoms, and an aminocarboxylic acid unit, and a polyetheramide elastomer.

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). (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 any one of claims 1 to 4, wherein the polyetheramide elastomer contains a polyalkylene glycol block and a polyamide block.

6. The resin composition according to claim 5, wherein the polyalkylene glycol block comprises a polypropylene glycol (PPG) block and / or a polytetramethylene ether glycol (PTMG) block.

7. A resin composition according to any one of claims 1 to 6, wherein the content of the polyamide resin in the resin composition is 80.0 to 99.9 mass %, and the content of the polyetheramide elastomer is 20.0 to 0.1 mass %.

8. The resin composition according to any one of claims 1 to 7, wherein the aliphatic dicarboxylic acid units having 7 to 20 carbon atoms include sebacic acid units and / or dodecanedioic acid units, the alicyclic diamine units include units represented by formula (PA-1), the polyetheramide elastomer includes a polyalkylene glycol block and a polyamide block, the polyalkylene glycol block includes a polypropylene glycol (PPG) block and / or a polytetramethylene ether glycol (PTMG) block, and the content of the polyamide resin in the resin composition is 80.0 to 99.9 mass%, and the content of the polyetheramide elastomer is 20.0 to 0.1 mass%. (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.

9. The resin composition according to any one of claims 1 to 8, wherein the aminocarboxylic acid constituting the aminocarboxylic acid unit is represented by formula (PA-2). (In formula (PA-2), n is an integer of 5 to 20.) 10. The resin composition according to any one of claims 1 to 9, wherein the polyamide resin is an amorphous resin.

11. The resin composition according to any one of claims 1 to 10, wherein the haze of the resin composition when molded into a film having a thickness of 300 μm is 3.0% or less.

12. The resin composition according to any one of claims 1 to 11, wherein the resin composition has a total light transmittance of 80% or more when molded into a film having a thickness of 300 μm.

13. The resin composition according to any one of claims 1 to 12, which is used as a protective film for a polarizing sheet.

14. A film formed from the resin composition according to any one of claims 1 to 13.

15. A polarizing sheet comprising the film according to claim 14 and a polarizing film.

16. Sunglasses comprising the polarizing sheet according to claim 15.

Images