Laminated film

Abstract

This invention provides a polycarbonate film that can enhance sliding properties without the use of lubricants such as inorganic particles or fluorine-based polymers. [Solution] A laminated film having a polycarbonate resin layer with polymer 2 as the main component polymer, and a thermoplastic resin layer with polymer 1 as the main component polymer on at least one of its outermost surfaces, wherein polymer 2 is a polycarbonate containing 50% by mass or more of the constituent unit represented by the following formula (2) of polymer 2, and polymer 1 is preferably one or more of polycarbonate, polyester, polyamide, and polyurethane. TIFF2026056042000021.tif46170

Description

Technical Field

[0001] The present invention relates to a laminated film having a polycarbonate resin layer and a thermoplastic resin layer.

Background Art

[0002] Since polycarbonate is a polymer excellent in transparency, heat resistance, and mechanical strength, films using polycarbonate are widely used in fields such as automotive parts, card members, building materials, displays, and electrical and electronic parts.

[0003] While polycarbonate has the above characteristics, due to its high surface friction coefficient, films using polycarbonate have poor slipperiness between smooth films, and are prone to problems such as film stacking, blocking, and damage due to friction between films during manufacturing and storage. Therefore, improvement of the slidability of the film surface has been demanded.

[0004] As means for improving the slidability of films using polycarbonate, for example, as in Patent Document 1, a method of imparting fine irregularities on the surface by blending inorganic particles, as in Patent Document 2, a method of adding a polymer or particles excellent in slidability such as a fluorine-based polymer, and as in Patent Document 3, a method of adding a lubricant such as silicone are disclosed.

Prior Art Documents

Patent Documents

[0005]

Patent Document 1

Patent Document 2

Patent Document 3

Summary of the Invention

Problems to be Solved by the Invention

[0006] As mentioned above, when inorganic particles, fluorine-based polymers, silicones, or other lubricants are blended into polycarbonate to improve the film's sliding properties, there is a risk of impairing the excellent mechanical strength of polycarbonate. Furthermore, there are concerns that the moldability may deteriorate, and in the case of particles, particle shedding may occur, or in the case of lubricants, bleed-out may occur, contaminating the manufacturing process.

[0007] Therefore, the present invention aims to provide a new film made of polycarbonate that can improve sliding properties without the use of lubricants such as inorganic particles or fluorine-based polymers. [Means for solving the problem]

[0008] The present inventors have found that the above problems can be solved by laminating a thermoplastic resin layer containing a suitable polymer on at least one of the outermost surfaces. The present invention was completed based on this finding, and its gist is as follows. However, the present invention is not limited to the following embodiments and also includes the scope of substitutions, modifications, etc., that can be made by those skilled in the art.

[0009] [1] A first aspect of the present invention is a laminated film having a polycarbonate resin layer with polymer 2 as the main component polymer, and having a thermoplastic resin layer with polymer 1 as the main component polymer on at least one of its outermost surfaces, The polymer 2 is a polycarbonate containing 50% by mass or more of the constituent units represented by the following formula (2), The polymer 1 is a laminated film containing a structural unit represented by the following formula (1).

[0010] TIFF2026056042000001.tif46170

[0011] TIFF2026056042000002.tif46170

[0012] In equation (1) above, n and m are integers greater than or equal to 1. In formula (2) above, X is at least one selected from a single bond, an oxygen atom, a sulfur atom, and a divalent organic group (excluding unsubstituted groups). R1 ​​to R4 are each independently a hydrogen atom, an alkyl group having 1 to 10 carbon atoms, or an aryl group having 6 to 12 carbon atoms.

[0013] [2] A second aspect of the present invention is a laminated film in which the polymer 1 contains 10% by mass or more of the constituent unit represented by formula (1) in the first aspect. [3] A third aspect of the present invention is a laminated film in which the polymer 1 is one or more of polycarbonate, polyester, polyamide, and polyurethane, in the first or second aspect. [4] A fourth aspect of the present invention is a laminated film in which the polymer 1 is polycarbonate in any one of the first to third aspects.

[0014] [5] A fifth aspect of the present invention is a laminated film in which, in any one of the first to fourth aspects, the constituent unit represented by formula (1) contained in the polymer 1 is represented by the following formula (3) or (4).

[0015] TIFF2026056042000003.tif40170

[0016] TIFF2026056042000004.tif42170

[0017] In equations (3) and (4), m is an integer greater than or equal to 1.

[0018] [6] A sixth aspect of the present invention is a laminated film in which, in any one of the first to fifth aspects, the polymer 1 contains 70% by mass or more and 90% by mass or less of the structural unit represented by formula (2) of the polymer 1.

[0019] [7] The seventh aspect of the present invention is the laminated film according to any one of the first to sixth aspects, wherein the polymer 1 has a structural unit represented by the formula (2), and R1 to R4 in the structure represented by the formula (2) are each independently a hydrogen atom or a methyl group. [8] The eighth aspect of the present invention is the laminated film according to any one of the first to sixth aspects, wherein the polymer 1 has a structural unit represented by the formula (2), and R1 to R4 in the structure represented by the formula (2) are all hydrogen atoms.

[0020] [9] The ninth aspect of the present invention is the laminated film according to any one of the first to eighth aspects, wherein the polymer 1 has a structural unit represented by the formula (2), and X in the structural unit represented by the formula (2) is a divalent organic group represented by the following formula (5).

[0021] TIFF2026056042000005.tif46170

[0022] In the formula (5), R5 and R6 are each independently a hydrogen atom, a monovalent hydrocarbon group having 1 to 24 carbon atoms, or an alkoxy group having 1 to 24 carbon atoms. R5 and R6 may be bonded to each other to form a ring. * is a bond to the benzene ring in the formula (2).

[0023]

[10] The tenth aspect of the present invention is the laminated film according to the ninth aspect, wherein R5 and R6 in the structure represented by the formula (5) are both methyl groups.

[0024]

[11] The eleventh aspect of the present invention is the laminated film according to any one of the first to tenth aspects, wherein the viscosity average molecular weight (Mv) of the polymer 1 is 15,000 or more and 32,000 or less.

[12] The twelfth aspect of the present invention is the laminated film according to any one of the first to eleventh aspects, wherein the glass transition temperature of the polymer 1 measured according to JIS K7121:2012 is 0°C or more and 100°C or less.

[0025]

[13] A thirteenth aspect of the present invention is a laminated film in which, in any one of the first to twelve aspects, R1 to R4 of the structure represented by formula (2) contained in the polymer 2 are each independently a hydrogen atom or a methyl group.

[14] A fourteenth aspect of the present invention is a laminated film in which, in any one of the first to twelve aspects, R1 to R4 of the structure represented by formula (2) contained in the polymer 2 are all hydrogen atoms.

[0026]

[15] A fifteenth aspect of the present invention is a laminated film in which, in any one of the first to fourteen aspects, X of the constituent unit represented by formula (2) contained in the polymer 2 is a divalent organic group represented by the following formula (5).

[0027] TIFF2026056042000006.tif46170

[0028] In formula (5), R5 and R6 are each independently a hydrogen atom, a monovalent hydrocarbon group having 1 to 24 carbon atoms, or an alkoxy group having 1 to 24 carbon atoms. R5 and R6 may be bonded to each other to form a ring. * represents a bond to the benzene ring in formula (2).

[0029]

[16] A sixteenth aspect of the present invention is a laminated film in which, in the fifteenth aspect, both R5 and R6 of the structure represented by formula (5) are methyl groups.

[0030]

[17] A seventeenth aspect of the present invention is a laminated film in which, in any one of the first to sixteen embodiments, the viscosity-average molecular weight (Mv) of the polymer 2 is 12,000 or more and 32,000 or less.

[18] An eighteenth aspect of the present invention is a laminated film in which, in any one of the first to seventeen aspects, the glass transition temperature of the polymer 2, as measured in accordance with JIS K7121:2012, is 100°C or more and 200°C or less.

[0031]

[19] A 19th aspect of the present invention is a laminated film in which, in any one of the first to eighteenth aspects, the layer thickness ratio of the thermoplastic resin layer to the polycarbonate resin layer is 1:99 to 50:50.

[20] A 20th aspect of the present invention is a laminated film having a thickness of 0.01 mm or more and 10 mm or less, in any one of the first to 19 aspects. [Effects of the Invention]

[0032] The present invention relates to a laminated film having a polycarbonate resin layer whose main component polymer is polymer 2 having a specific configuration, wherein by arranging a thermoplastic resin layer whose main component polymer is polymer 1 having a specific configuration on at least one of the outermost surfaces, the sliding properties can be improved without using lubricants such as inorganic particles or fluorine-based polymers. [Modes for carrying out the invention]

[0033] An example of an embodiment of the present invention will be described below. However, the present invention is not limited to the embodiment described below.

[0034] <Laminated film of the present invention> A laminated film according to an example of an embodiment of the present invention (referred to as "the laminated film of the present invention") is a laminated film having a polycarbonate resin layer whose main component polymer is polycarbonate, and having a thermoplastic resin layer whose main component polymer is thermoplastic resin on at least one of its outermost surfaces.

[0035] Here, the "main component polymer" refers to the polymer with the highest mass percentage among the polymers contained in the polycarbonate layer or thermoplastic resin layer. For example, it can be assumed that the polymer contains 50% by mass or more, particularly 60% by mass or more, particularly 70% by mass or more, particularly 80% by mass or more, particularly 90% by mass or more, or particularly 90% by mass or more (including 100% by mass) of the total amount of polymers contained in the polycarbonate layer or thermoplastic resin layer (100% by mass). In this invention, "polymer" refers to a so-called polymer, encompassing synthetic polymers and natural polymers, and is a compound formed by the polymerization of multiple monomers, with a molecular weight of 10,000 or more.

[0036] The laminated film of the present invention has a polycarbonate resin layer and a thermoplastic resin layer on at least one of its outermost surfaces; however, the presence of other layers is optional. For example, typically, a laminated configuration of thermoplastic resin layer / polycarbonate resin layer, or thermoplastic resin layer / polycarbonate resin layer / thermoplastic resin layer can be exemplified. In these laminated configurations, the "other layer" may be located outside one of the thermoplastic resin layers, or the "other layer" may be located between the thermoplastic resin layer and the polycarbonate resin layer. These "other layers" may be single layers or multilayer layers of two or more layers.

[0037] <Thermoplastic resin layer> The thermoplastic resin layer is a layer whose main component polymer is polymer 1, which contains the structural units represented by the following formula (1).

[0038] By including the constituent units represented by the following formula (1), the glass transition temperature (Tg) of polymer 1 becomes relatively low, resulting in a relatively soft thermoplastic resin layer that can release stress during sliding. Therefore, it is presumed that the sliding properties of the laminated film of the present invention can be improved by having a thermoplastic resin layer on the outermost surface whose main component polymer is polymer 1 containing the constituent units represented by the following formula (1).

[0039] TIFF2026056042000007.tif46170

[0040] In equation (1), n ​​and m are integers greater than or equal to 1. n can be assumed to be an integer between 1 and 10, specifically between 2 and 5, and between 3 and 4. m can be assumed to be an integer between 4 and 100, specifically between 5 and 90, and between 6 and 80.

[0041] The polymer 1 preferably contains 10% by mass or more of the constituent unit represented by formula (1) from the viewpoint of Tg control. Regarding the upper limit, from the viewpoint of Tg control, it is preferable that it contains 40% by mass or less of the polymer 1. From this viewpoint, the polymer 1 is preferably one that contains 10% by mass or more of the constituent unit represented by formula (1), more preferably 12% by mass or more, more preferably 14% by mass or more, more preferably 16% by mass or more, and more preferably 18% by mass or more. On the other hand, it is preferable that it contains 40% by mass or less of the polymer 1, more preferably 35% by mass or less, and more preferably 30% by mass or less.

[0042] It is preferable that the constituent unit represented by formula (1) contained in polymer 1 is a constituent unit represented by the following formula (3) or (4).

[0043] TIFF2026056042000008.tif40170

[0044] TIFF2026056042000009.tif42170

[0045] In equations (3) and (4), m is an integer greater than or equal to 1. We can assume that m is an integer between 4 and 100, and more specifically, between 5 and 90, and more specifically, between 6 and 80.

[0046] As described above, it is presumed that any polymer 1 containing the structural unit represented by formula (1) can improve the sliding properties of the thermoplastic resin layer. From the viewpoint of film moldability, the polymer 1 is preferably one or more of polycarbonate, polyester, polyamide, and polyurethane. Of these, polycarbonate is preferred from the viewpoint of interlayer adhesion. The constituent units represented by formula (1) are derived from aliphatic dihydroxy compounds such as polytetramethylene ether glycol and polytrimethylene ether glycol. For example, these constituent units can be introduced into polymers such as polycarbonate, polyester, polyamide, and polyurethane by copolymerizing polymers using aliphatic dihydroxy compounds as copolymerization raw materials.

[0047] From the viewpoint of mechanical strength, the polymer 1 is preferably one that includes the constituent units represented by formula (2).

[0048] TIFF2026056042000010.tif46170

[0049] In formula (2), R1 to R4 are each independently a hydrogen atom, an alkyl group having 1 to 10 carbon atoms, or an aryl group having 6 to 12 carbon atoms. Of these, from the viewpoint of moldability, it is preferable that R1 to R4 are each independently a hydrogen atom or a methyl group. Of these, from the viewpoint of mechanical strength, it is preferable that they are all hydrogen atoms.

[0050] In formula (2), X is at least one selected from a single bond, an oxygen atom, a sulfur atom, and a divalent organic group (excluding unsubstituted groups). Of these, from the viewpoint of mechanical strength, a divalent organic group represented by formula (5) is preferred.

[0051] TIFF2026056042000011.tif46170

[0052] In formula (5), R5 and R6 are each independently a hydrogen atom, a monovalent hydrocarbon group having 1 to 24 carbon atoms, or an alkoxy group having 1 to 24 carbon atoms. R5 and R6 may be bonded to each other to form a ring. Of these, from the viewpoint of mechanical strength, it is preferable that both R5 and R6 are methyl groups. * represents the bond to the benzene ring in formula (2).

[0053] The content of the constituent unit represented by formula (2) in polymer 1 is preferably 70% by mass or more and 90% by mass or less of polymer 1, more preferably 72% by mass or more or 88% by mass or less, and more preferably 75% by mass or more or 85% by mass or less.

[0054] The viscosity-average molecular weight (Mv) of polymer 1 is preferably 32,000 or less from the viewpoint of moldability, more preferably 30,000 or less, and more preferably 28,000 or less. On the other hand, the viscosity-average molecular weight (Mv) of polymer 1 is preferably 15,000 or more from the viewpoint of mechanical strength, more preferably 16,000 or more, and more preferably 17,000 or more. Furthermore, the difference in viscosity-average molecular weight (Mv) between polymer 1 and polymer 2 is preferably 10,000 or less, more preferably 8,000 or less, and even more preferably 6,000 or less, and may even be 0, in order to suppress defects during molding due to viscosity differences.

[0055] The glass transition temperature of polymer 1, as measured in accordance with JIS K7121:2012, is preferably 0°C or higher, more preferably 10°C or higher, and more preferably 20°C or higher, from the viewpoint of sliding properties. On the other hand, if the glass transition temperature of polymer 1 is too high, the elastic modulus increases and the sliding properties decrease, so it is preferably 100°C or lower, more preferably 95°C or lower, and more preferably 90°C or lower. Furthermore, from the viewpoint of moldability, the difference in glass transition temperatures between polymer 1 and polymer 2 is preferably 160°C or less, more preferably 140°C or less, and even more preferably 120°C or less. On the other hand, from the viewpoint of sliding properties, the difference between the two is preferably 0°C or more, more preferably 20°C or more, and even more preferably 40°C or more.

[0056] The polymer 1 is preferably amorphous and preferably does not have a crystalline melting temperature as measured in accordance with JIS K7121:2012. In particular, if the polymer 1 is polycarbonate, it is amorphous and therefore preferably does not have the crystalline melting temperature.

[0057] The polymer 1 preferably has an apparent viscosity of 80 Pa·s or more at 240°C with a shear rate of 100 (1 / s) from the viewpoint of mechanical strength, more preferably 90 Pa·s or more, and more preferably 100 Pa·s or more. On the other hand, from the viewpoint of moldability, it is preferably 1,000 Pa·s or less, more preferably 800 Pa·s or less, and more preferably 600 Pa·s or less. Furthermore, the difference in apparent viscosity between polymer 1 and polymer 2 at 240°C with a shear rate of 100 (1 / s) is preferably small, preferably 800 Pa·s or less, more preferably 600 Pa·s or less, even more preferably 400 Pa·s or less, and most preferably 0.

[0058] (Other ingredients) The thermoplastic resin layer may contain components other than polymer 1 as needed. Examples include other polymers and other additives. Other polymers include, for example, thermoplastic polyesters such as polyethylene terephthalate, polytrimethylene terephthalate, and polybutylene terephthalate; styrene polymers such as polystyrene, high-impact polystyrene (HIPS), acrylonitrile-styrene copolymer (AS resin), acrylonitrile-styrene-acrylic rubber copolymer (ASA resin), and acrylonitrile-ethylene propylene rubber-styrene copolymer (AES resin); polyolefins such as polyethylene and polypropylene; polyamides; polyimides; polyetherimides; polyurethanes; polyphenylene ethers; polyphenylene sulfides; polysulfones; and polymethacrylates. These polymers may be present individually or in any combination and ratio. Examples of additives include heat stabilizers, antioxidants, mold release agents, lightfastness agents (HALS), flame retardants, antistatic agents, antifogging agents, lubricants, antiblocking agents, flow improvers, plasticizers, dispersants, antibacterial agents, dyes, and pigments. Note that the product may contain only one additive, or two or more additives in any combination and ratio.

[0059] (Content ratio) In the thermoplastic resin layer, the content of polymer 1 is preferably high in terms of sliding properties, preferably 60% by mass or more, more preferably 70% by mass or more, and even more preferably 80% by mass or more.

[0060] <Polycarbonate resin layer> The polycarbonate resin layer is a layer whose main component polymer is polymer 2, which contains the structural units represented by the following formula (2).

[0061] (Polymer 2) From the viewpoint of moldability, the polymer 2 preferably contains 50% by mass or more of the constituent unit represented by the following formula (2), and may contain 100% by mass. From this viewpoint, the polymer 2 is preferably one that contains 50% by mass or more of the constituent unit represented by the following formula (2), more preferably 60% by mass or more, of which 70% by mass or more, of which 80% by mass or more, and of which 90% by mass or more, and may contain 100% by mass. It is preferable that polymer 2 is a polymer different from polymer 1, and more preferably that polymer contains the constituent unit represented by the following formula (2) but does not contain the constituent unit represented by the aforementioned formula (1).

[0062] TIFF2026056042000012.tif46170

[0063] In formula (2), R1 to R4 are each independently a hydrogen atom, an alkyl group having 1 to 10 carbon atoms, or an aryl group having 6 to 12 carbon atoms. From a synthetic viewpoint, it is preferable that R1 to R4 are each independently a hydrogen atom or a methyl group. From a mechanical strength viewpoint, it is preferable that they are all hydrogen atoms.

[0064] In formula (2), X is at least one selected from a single bond, an oxygen atom, a sulfur atom, and a divalent organic group (excluding unsubstituted groups). Of these, from the viewpoint of mechanical strength, a divalent organic group represented by formula (5) is preferred.

[0065] TIFF2026056042000013.tif46170

[0066] In formula (5), R5 and R6 are each independently a hydrogen atom, a monovalent hydrocarbon group having 1 to 24 carbon atoms, or an alkoxy group having 1 to 24 carbon atoms. R5 and R6 may be bonded to each other to form a ring. Of these, from the viewpoint of mechanical strength, it is preferable that both R5 and R6 are methyl groups. * represents the bond to the benzene ring in formula (2).

[0067] The content of the constituent unit represented by formula (2) in polymer 2 is preferably 50% by mass or more, more preferably 70% by mass or more, and more preferably 90% by mass or more, and may even be 100% by mass.

[0068] The viscosity-average molecular weight (Mv) of polymer 2 is preferably 32,000 or less, more preferably 30,000 or less, and more preferably 28,000 or less, from the viewpoint of moldability. On the other hand, if the viscosity-average molecular weight (Mv) of polymer 2 is too small, the mechanical strength will decrease, so it is preferably 12,000 or more, more preferably 14,000 or more, and more preferably 15,000 or more.

[0069] The glass transition temperature of polymer 2, as measured in accordance with JIS K7121:2012, is preferably 100°C or higher, more preferably 120°C or higher, and even more preferably 140°C or higher, from the viewpoint of imparting sliding properties. On the other hand, if the glass transition temperature of polymer 2 is too high, molding becomes difficult, so it is preferably 200°C or lower, more preferably 180°C or lower, and even more preferably 160°C or lower.

[0070] In order to ensure sliding properties, it is preferable that the polymer 2 does not have a crystal melting temperature measured in accordance with JIS K7121:2012.

[0071] The polymer 2 preferably has an apparent viscosity of 80 Pa·s or more at 270°C with a shear rate of 100 (1 / s) from the viewpoint of mechanical strength, more preferably 90 Pa·s or more, and more preferably 100 Pa·s or more. On the other hand, from the viewpoint of moldability, it is preferably 1,500 Pa·s or less, more preferably 1,200 Pa·s or less, and more preferably 1,000 Pa·s or less.

[0072] (Other ingredients) The polycarbonate resin layer may contain components other than polymer 2 as needed. Examples include other polymers and other additives. Other polymers include, for example, thermoplastic polyesters such as polyethylene terephthalate, polytrimethylene terephthalate, and polybutylene terephthalate; styrene polymers such as polystyrene, high-impact polystyrene (HIPS), acrylonitrile-styrene copolymer (AS resin), acrylonitrile-styrene-acrylic rubber copolymer (ASA resin), and acrylonitrile-ethylene propylene rubber-styrene copolymer (AES resin); polyolefins such as polyethylene and polypropylene; polyamides; polyimides; polyetherimides; polyurethanes; polyphenylene ethers; polyphenylene sulfides; polysulfones; and polymethacrylates. These polymers may be present individually or in any combination and ratio. Examples of additives include heat stabilizers, antioxidants, mold release agents, lightfastness agents (HALS), flame retardants, antistatic agents, antifogging agents, lubricants, antiblocking agents, flow improvers, plasticizers, dispersants, antibacterial agents, dyes, and pigments. Note that the product may contain only one additive, or two or more additives in any combination and ratio.

[0073] (Content ratio) In the polycarbonate resin layer, the content of polymer 2 is preferably 50% by mass or more, more preferably 60% by mass or more, and even more preferably 70% by mass or more, and may even be 100% by mass, from the viewpoint of maintaining the properties of polycarbonate.

[0074] <Layering> From the viewpoint of sliding properties, the thickness of the thermoplastic resin layer is preferably 1 μm or more, more preferably 3 μm or more, and more preferably 5 μm or more. On the other hand, from the viewpoint of mechanical strength, it is preferably 10 mm or less, more preferably 5 mm or less, and more preferably 1 mm or less.

[0075] From the viewpoint of mechanical strength, the thickness of the polycarbonate resin layer is preferably 10 μm or more, more preferably 15 μm or more, and more preferably 20 μm or more. On the other hand, from the viewpoint of sliding properties, it is preferably 10 mm or less, more preferably 5 mm or less, and more preferably 1 mm or less.

[0076] The thickness ratio of the thermoplastic resin layer (each layer) to the polycarbonate resin layer is preferably 1:99 to 50:50 from the viewpoint of sliding properties, and more preferably 5:95 to 40:60, of which 10:90 to 30:70, and of which 15:85 to 40:60.

[0077] The thickness of the laminated film of the present invention is preferably 0.01 mm or more from the viewpoint of moldability, more preferably 0.03 mm or more, and more preferably 0.05 mm or more. On the other hand, from the viewpoint of sliding properties, it is preferably 10 mm or less, more preferably 8 mm or less, and more preferably 5 mm or less.

[0078] <Physical properties of the laminated film of the present invention> The laminated film of the present invention may have the following physical properties.

[0079] (Coefficient of friction) The laminated film of the present invention preferably has a static friction coefficient and a dynamic friction coefficient of less than 0.30, as measured in accordance with JIS K7125:1999, and is particularly preferably less than 0.25.

[0080] (Puncture shock) The laminated film of the present invention preferably has a puncture impact strength of 1.0 J or more, measured at temperatures of -20°C and 23°C in accordance with JIS K7124-2:1999, and is particularly preferably 1.5 J or more.

[0081] <Method for manufacturing the laminated film of the present invention> The laminated film of the present invention can be manufactured by various methods, but it is preferable to manufacture it by the following method, for example. The laminated film of the present invention can be manufactured by a co-extrusion method, in which the raw materials for the polycarbonate resin layer and the thermoplastic resin layer are melted in one or more extruders, extruded from a flat die or annular die, and then rapidly cooled to form a flat or annular unstretched film. A more specific example is a manufacturing method in which the raw materials for the polycarbonate resin layer and the thermoplastic resin layer are each fed into an extruder, melted, distributed in a distribution block, multilayered in a co-extrusion T-die, the molten film is extruded, and cooled on a cooling roll to produce the laminated film of the present invention.

[0082] <Explanation of Terms> In this invention, "film" encompasses "sheet". Furthermore, in this invention, when "x~y" (where x and y are any numbers) is written, unless otherwise specified, it includes the meaning of "greater than or equal to x and less than or equal to y," as well as the meaning of "preferably greater than x" or "preferably less than y." Furthermore, "greater than or equal to x" (where x is any number) generally means "preferably greater than x" unless otherwise specified, and "less than or equal to y" (where y is any number) generally means "preferably less than y" unless otherwise specified. [Examples]

[0083] Next, the present invention will be described in more detail with reference to examples. However, the present invention is not limited to the examples described below.

[0084] <Evaluation Method> (1) Glass transition temperature (Tg) and crystal melting temperature The glass transition temperature and crystal melting temperature of the polymer were measured in accordance with JIS K7121:2012. A differential scanning calorimeter (DSC) manufactured by PerkinElmer was used for the measurements. The glass transition temperature and crystal melting temperature of the polymer were determined from the inflection point and endothermic peak top temperature of the DSC curve of the polymer pellet detected during the reheating process at a temperature range of 30 to 300°C and a heating rate of 10°C / min.

[0085] (2) Viscosity average molecular weight (Mv) The polymer was dissolved in methylene chloride (concentration 6.0 g / L), and the intrinsic viscosity (intrinsic viscosity) [η] (unit dL / g) at 20°C was determined using an Ubbelohde viscosity tube (manufactured by Moritomo Rika Kogyo Co., Ltd.). The viscosity-average molecular weight (Mv) of the polymer was then calculated from Schnell's viscosity equation (see below). η = 1.23 × 10 -4 Mv 0.83

[0086] (3) Apparent viscosity The apparent viscosity of the polymer at 240°C or 270°C at a shear rate of 100 (1 / s) was measured using a high-efficiency flow tester (manufactured by Shimadzu Corporation) equipped with a nozzle of φ1 × L10 mm.

[0087] (4) Sliding properties The sliding properties of the obtained laminated film (sample) were measured by the coefficient of friction in accordance with JIS K7125:1999. For each laminated film (sample) with a thickness of 100 μm, the static and dynamic friction coefficients were measured using a plastic film slip tester (manufactured by Intesco) at a test speed of 100 mm / min, with a weight of 200 g, a static friction section of 5 mm, and a dynamic friction section of 60 mm with stainless steel (SUS430). The total mass of the sliding piece was 200 g (contact area of ​​a square with sides of 63 mm), and the contact area was 40 cm². 2 That's what I decided. For both the static and kinetic friction coefficients, a coefficient of friction less than 0.25 at 23°C and 50%RH was evaluated as "(A)", a coefficient between 0.25 and 0.30 was evaluated as "(B)", and a coefficient of friction of 0.30 or greater was evaluated as "(C)".

[0088] (5) Impact resistance The impact resistance of the obtained laminated film (sample) was measured by puncture impact strength in accordance with JIS K7124-2:1999. Each laminated film (sample) with a thickness of 100 μm was measured using a high-speed puncture impact tester HydroShot HITS-P10 (Shimadzu Corporation) at temperatures of 23°C and -20°C, with a punching diameter of 0.5 inches and a test speed of 3 m / sec. A puncture impact strength of 1.0 J or higher was evaluated as "(A)" under the respective temperature conditions of 23°C and -20°C, and a puncture impact strength of less than 1.0 J was evaluated as "(C)".

[0089] <Material> Polymer (A)-1: A polycarbonate copolymer synthesized according to Preparation Example 1 below, using bisphenol A and PTMG3000 as copolymerization raw materials, with a ratio of bisphenol A:PTMG3000 = 80:20 (by weight). Tg 86℃, no crystal melting temperature. Mv 20,000, apparent viscosity at 270℃ with a shear rate of 100 (1 / s) 4.8 × 10⁻⁶ 2 Pa·s It contains 20% by mass of the constituent unit represented by formula (1) and 80% by mass of the constituent unit represented by formula (2). The constituent unit represented by formula (1) is the same as the constituent unit represented by formula (3). In formula (2), R1 to R4 are all hydrogen atoms. X is a divalent organic group represented by formula (5), and in formula (5), R5 and R6 are both methyl groups.

[0090] Polymer (A)-2: A polycarbonate copolymer synthesized by Preparation Example 2 below, using bisphenol A and PO3G2700 as copolymerization raw materials, with a ratio of bisphenol A:PO3G2700 = 80:20 (by weight). Tg 50℃, no crystal melting temperature. Mv 24,800, apparent viscosity at 240℃ with a shear rate of 100 (1 / s) 3.7 × 10⁻⁶ 2 Pa·s It contains 20% by mass of the constituent unit represented by formula (1) and 80% by mass of the constituent unit represented by formula (2). The constituent unit represented by formula (1) is the same as the constituent unit represented by formula (4). In formula (2), R1 to R4 are all hydrogen atoms. X is a divalent organic group represented by formula (5), and in formula (5), R5 and R6 are both methyl groups.

[0091] Polymer (A)-3: Bisphenol A type polycarbonate (Mitsubishi Engineering Plastics Co., Ltd. "Yupilon H-3000") Tg 145℃, no crystal melting temperature. Mv 17,700, apparent viscosity at 240℃ with a shear rate of 100 (1 / s) 4.6 × 10⁻⁶ 2 Pa·s It contains 100% by mass of the constituent unit represented by formula (2). In formula (2), R1 to R4 are all hydrogen atoms. X is a divalent organic group represented by formula (5), and in formula (5), R5 and R6 are both methyl groups.

[0092] [Preparation Example 1] In a first reactor equipped with a stirrer, heat transfer jacket, vacuum pump, and reflux condenser, 1327 g (approximately 0.465 mol) of PTMG3000 (polytetramethylene ether glycol, number average molecular weight 2855 (manufactured by Mitsubishi Chemical Corporation)), 5308 g (approximately 23.3 mol) of BPA (bisphenol A), 5335 g (approximately 24.7 mol) of DPC (diphenyl carbonate), and a 0.50 wt% aqueous solution of cesium carbonate as a catalyst were added, with the amount of cesium carbonate being 1.00 μmol per mol of total dihydroxy compounds. After purging the reactor with nitrogen gas, the temperature was raised to 220°C over 30 minutes under a nitrogen gas atmosphere. At the same temperature, the pressure in the reactor was reduced to 100 Torr over 40 minutes, and the reaction was continued for another 80 minutes, after which the phenol was distilled off.

[0093] Next, the temperature inside the reactor was raised to 260°C over 60 minutes, and the pressure was reduced to 3 Torr, allowing almost the entire theoretical amount of phenol to be distilled off. Then, the pressure inside the reactor was maintained at less than 1 Torr at the same temperature, and the reaction was continued for approximately 240 minutes until the predetermined stirring power was reached, thus completing the polycondensation reaction. At this time, the stirring speed of the stirrer was 30 revolutions per minute, the reaction solution temperature just before the end of the reaction was 260°C, and the stirring power was 0.50 kW. Next, the reactor was repressurized to an absolute pressure of 101.3 kPa using nitrogen, and then increased to a gauge pressure of 0.2 MPa. Polycarbonate was then extracted in strand form from the bottom of the reactor tank, and after obtaining the stranded polycarbonate, it was pelletized using a rotary cutter.

[0094] To the above pellets, butyl p-toluenesulfonate was added in an amount 2.5 times the molar amount relative to cesium carbonate, fed into a twin-screw extruder, and kneaded at 260°C. The reaction mixture was then extruded in strand form through the die of the twin-screw extruder and cut with a cutter to obtain pellets of polymer (A)-1.

[0095] [Preparation Example 2] Polymer (A)-2 was obtained by polymerization and kneading of a deactivator using the method described in Preparation Example 1, except that a raw material mixture was prepared by adding 1325 g (approximately 0.487 mol) of PO3G2700 (polytrimethylene ether glycol, number average molecular weight 2723 (manufactured by ALLESSA)), 5300 g (approximately 23.2 mol) of BPA (bisphenol A), 5281 g (approximately 24.7 mol) of DPC (diphenyl carbonate), and a 0.50 wt% aqueous solution of cesium carbonate as a catalyst, so that the amount of cesium carbonate was 1.0 μmol per mol of total dihydroxy compounds.

[0096] <Examples 1-2, Comparative Example 1> As shown in Table 1, polymers (A)-1 to (A)-3, which serve as raw materials for the surface and back layers respectively, were introduced into a φ32 mm extruder and melted at 240°C. Polymers (A)-1 to (A)-3, which serve as raw materials for the middle layer, were introduced into a φ40 mm extruder and melted at 270°C. The mixture was then distributed in a distribution block and multilayered in a co-extrusion T-die. The molten film was extruded so that the layer thickness ratio (%) of the surface / middle / back layers was 20 / 60 / 20, and the film was cooled on a cooling roll at 100°C to produce a 100 μm thick laminated film (sample).

[0097] [Table 1]

[0098] As shown in Table 1, the laminated films having a surface layer containing a predetermined thermoplastic polymer, as in Examples 1 and 2, exhibited low dynamic and static friction coefficients and good sliding properties. Furthermore, they showed excellent impact resistance derived from polycarbonate. On the other hand, in the case of a single-layer film made of a polycarbonate resin layer, as in Comparative Example 1, although it had excellent impact resistance, it had high dynamic and static friction coefficients and lacked sliding properties.

[0099] From the above examples and comparative examples, as well as the test results conducted by the present inventors to date, it has been found that a laminated film having a polycarbonate resin layer and a thermoplastic resin layer on at least one of its outermost surfaces, in which polymer 1 containing the constituent unit represented by formula (1) is the main component polymer, has excellent impact resistance and can improve sliding properties without the use of lubricants such as inorganic particles or fluorine-based polymers. By including the constituent units represented by formula (1), the glass transition temperature (Tg) of polymer 1 becomes relatively low, resulting in a relatively soft thermoplastic resin layer that can release stress during sliding. Therefore, it is presumed that the sliding properties of the laminated film of the present invention can be improved by having a thermoplastic resin layer on the outermost surface, in which polymer 1 containing the constituent units represented by formula (1) is the main component polymer. [Industrial applicability]

[0100] The laminated film of the present invention exhibits unique sliding properties and excellent impact resistance, making it extremely useful for automotive, card, building, display, and electrical / electronic applications.

Claims

1. A laminated film having a polycarbonate resin layer with polymer 2 as the main component polymer, and having a thermoplastic resin layer with polymer 1 as the main component polymer on at least one of its outermost surfaces, The polymer 2 is a polycarbonate resin containing 50% by mass or more of the constituent unit represented by the following formula (2). A laminated film in which the polymer 1 includes a structural unit represented by the following formula (1). [In equation (1), n ​​and m are integers greater than or equal to 1.] In formula (2), X is at least one selected from a single bond, an oxygen atom, a sulfur atom, and a divalent organic group (excluding unsubstituted groups). 1 ~R ４ Each of these is independently a hydrogen atom, an alkyl group having 1 to 10 carbon atoms, or an aryl group having 6 to 12 carbon atoms.

2. The laminated film according to claim 1, wherein the polymer 1 contains 10% by mass or more of the constituent unit represented by formula (1) of the polymer 1.

3. The laminated film according to claim 1, wherein the polymer 1 is one or more of polycarbonate, polyester, polyamide, and polyurethane.

4. The laminated film according to claim 1, wherein the polymer 1 is polycarbonate.

5. The laminated film according to claim 1, wherein the constituent unit represented by formula (1) contained in the polymer 1 is represented by the following formula (3) or (4). [In equations (3) and (4), m is an integer greater than or equal to 1.]

6. The laminated film according to claim 1, wherein the polymer 1 contains 70% by mass or more and 90% by mass or less of the constituent unit represented by formula (2) of the polymer 1.

7. The polymer 1 has a structural unit represented by formula (2), and the structure R represented by formula (2) 1 ~R ４ The laminated film according to claim 1, wherein each of them is independently a hydrogen atom or a methyl group.

8. The polymer 1 has a structural unit represented by formula (2), and the structure R represented by formula (2) 1 ~R ４ The laminated film according to claim 1, wherein all of them are hydrogen atoms.

9. The laminated film according to claim 1, wherein the polymer 1 has a structural unit represented by formula (2), and X of the structural unit represented by formula (2) is a divalent organic group represented by the following formula (5). [In formula (5), R ５ and R ６ are each independently a hydrogen atom, a monovalent hydrocarbon group having 1 to 24 carbon atoms, or an alkoxy group having 1 to 24 carbon atoms. R ５ and R ６ may be bonded to each other to form a ring. * is a bond to the benzene ring in formula (2).]

10. The structure R represented by formula (5) ５ and R ６ The laminated film according to claim 9, wherein all of them are methyl groups.

11. The laminated film according to claim 1, wherein the viscosity-average molecular weight (Mv) of the polymer 1 is 15,000 or more and 32,000 or less.

12. The laminated film according to claim 1, wherein the glass transition temperature of the polymer 1, as measured in accordance with JIS K7121:2012, is 0°C or higher and 100°C or lower.

13. The structure represented by formula (2) contained in the polymer 2 is R 1 ~R ４ The laminated film according to claim 1, wherein each of them is independently a hydrogen atom or a methyl group.

14. The structure represented by formula (2) contained in the polymer 2 is R 1 ~R ４ The laminated film according to claim 1, wherein all of them are hydrogen atoms.

15. The laminated film according to claim 1, wherein X of the constituent unit represented by formula (2) contained in the polymer 2 is a divalent organic group represented by the following formula (5). [In formula (5), R ５ and R ６ Each of these is independently a hydrogen atom, a monovalent hydrocarbon group having 1 to 24 carbon atoms, or an alkoxy group having 1 to 24 carbon atoms. ５ and R ６ These may be bonded to each other to form a ring. * represents a bond to the benzene ring in formula (2).

16. The above R of the structure represented by formula (5) ５ and R ６ The laminated film according to claim 15, wherein all of them are methyl groups.

17. The laminated film according to claim 1, wherein the viscosity-average molecular weight (Mv) of the polymer 2 is 12,000 or more and 32,000 or less.

18. The laminated film according to claim 1, wherein the glass transition temperature of the polymer 2, as measured in accordance with JIS K7121:2012, is 100°C or more and 200°C or less.

19. The laminated film according to claim 1, wherein the layer thickness ratio of the thermoplastic resin layer to the polycarbonate resin layer is 1:99 to 50:

50.

20. The laminated film according to claim 1, wherein the thickness is 0.01 mm or more and 10 mm or less.

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