JP5982851B2 - Aromatic polyamide film and method for producing the same - Google Patents

Description

  The present invention relates to an aromatic polyamide film having a large light transmittance in the visible light region even when a polymer having a 2,2′-dimethyl-biphenyl structure is used, and a method for producing the same.

  Currently, glass substrates are used for display devices such as liquid crystal displays and electronic paper, but there are problems such as heavy and cracking, and in recent years the development of flexible display devices has been promoted, so it is transparent and lightweight. Development of a plastic substrate having high toughness, high heat resistance, and high dimensional stability is demanded. However, when creating an actual display substrate, it includes steps such as cleaning the substrate using various solvents, so it is not sufficient to satisfy these characteristics, and resistance to the solvent is also required. It has been.

  Patent Document 1 proposes a molded article in which a 2,2′-ditrifluoromethyl-biphenyl structure is introduced into a polymer structure and has colorless transparency, high toughness, high heat resistance, and high dimensional stability. However, due to the introduction of bulky ditrifluoromethyl groups, polymer chain packing is hindered, resulting in low resistance to solvents, and in particular, there are problems of deformation, swelling, and cloudiness when contacted with acetone.

  Patent Document 2 proposes an aromatic polyamide using o-tolidine having a structure similar to the 2,2′-dimethyl-biphenyl structure, but it is highly colored and has a light transmittance of light in the visible light region. It is low and cannot be used as a display substrate.

  In Patent Documents 3 to 5, aromatic polyamides having a 2,2′-dimethyl-biphenyl structure are proposed, but as in Patent Document 2, coloring is large and light transmittance of light in the visible light region is low. It cannot be used as a display substrate.

  Further, Patent Document 6 proposes a film in which an inorganic compound and a resin having a glass transition temperature of 250 ° C. or more are combined and has excellent gas barrier properties and heat resistance, but has a problem that the thermal expansion coefficient is large. Furthermore, there is no description or suggestion that the light transmittance of wavelengths in the visible light region can be improved by compounding with a silicon compound.

International Publication No. 2004-039863 Pamphlet JP 2005-23106 A JP-A-3-143923 Japanese Patent Laid-Open No. 2-194022 JP 63-165515 A JP 2005-264135 A

  The present invention has been achieved as a result of studying the solution of the problems in the prior art described above as an issue. That is, an object of the present invention is to provide an aromatic polyamide film having a high light transmittance in the visible light region and a method for producing the same even when a polymer having a 2,2′-dimethyl-biphenyl structure introduced into the polymer structure is used. There is to do.

To achieve the above object, the present invention provides a silicon-containing fragrance in which a structural unit of an aromatic polyamide having a 2,2′-dimethyl-biphenyl structure and a structural unit derived from a specific silicon compound are combined in a polymer structure. The light transmittance of light having a wavelength of 385 nm is 15% or more, has resistance to acetone, and the average thermal expansion coefficient from 100 ° C. to 200 ° C. in at least one direction is 0 ppm / ° C. or more. It is an aromatic polyamide film having a concentration of 40 ppm / ° C. or less.

  According to the present invention, when not only having transparency, light weight, high toughness, high heat resistance, and high dimensional stability, which can be suitably used for a display material substrate, a solvent is used in the process of producing a display substrate. In addition, it becomes possible to provide a film having high process suitability.

  The aromatic polyamide film of the present invention includes a silicon-containing aromatic polyamide in which a structural unit of an aromatic polyamide having a structural unit represented by the chemical formula (I) and a structural unit derived from a silicon compound are bonded. All of 1) to (3) are satisfied.

  (1) The light transmittance of light having a wavelength of 385 nm is 15% or more.

  (2) Resistant to acetone.

  (3) The average coefficient of thermal expansion from 100 ° C. to 200 ° C. in at least one direction is 0 ppm / ° C. or more and 40 ppm / ° C. or less.

  Since the 2,2′-dimethyl-biphenyl structure represented by the chemical formula (I) is para-oriented, the average thermal expansion coefficient can be reduced by introducing it into the polymer structure, and the packing between molecular chains can be reduced. This is preferable because the resistance to an organic solvent is increased.

  When the structural unit represented by the chemical formula (I) is not included in the polymer structure, the average thermal expansion coefficient from 100 ° C. to 200 ° C. in at least one direction is 0 ppm / ° C. to 40 ppm / ° C. It becomes difficult to achieve both resistance.

The light transmittance of light having a wavelength of 385 nm is more preferably 20% or more, and further preferably 25% or more. Even more preferably, it is 30% or more. When the light transmittance of light having a wavelength of 385 nm is less than 15%, the light transmittance of light in the visible light region is lowered, and when used as a display, the brightness and brightness of a display image may be lowered. In order to improve the light transmittance, it is important to introduce a structural unit derived from the silicon compound represented by the chemical formula (II). In order to further improve the light transmittance, it is preferable to introduce an electron withdrawing group or a bent structure into the polymer structure. _-CF 3 as the electron-withdrawing _{group, -CCl 3, -CBr 3, -F} , -Cl, -Br, -I, etc. -NO 2, -CN, -COCH ₃ can be exemplified. The structure containing an electron withdrawing group or the structure containing a bending component is more preferably a structural unit represented by the chemical formula (V). More preferably, it is a structural unit represented by the chemical formula (VI).

R ¹ : methyl or phenyl (however, structural units having these groups may be mixed in the molecule)
R ² : methyl or phenyl (however, structural units having these groups may be mixed in the molecule)
R ³ : H, OH, methyl, ethyl, methoxy, or ethoxy (however, structural units having these groups may be mixed in the molecule)
R ⁴ : H, OH, methyl, ethyl, methoxy, or ethoxy (however, structural units having these groups may be mixed in the molecule)
R ⁵ : H, OH, methyl, ethyl, methoxy, or ethoxy (however, structural units having these groups may be mixed in the molecule)
R ⁶ : H, OH, methyl, ethyl, methoxy, or ethoxy (however, structural units having these groups may be mixed in the molecule)

  The aromatic polyamide film of the present invention has resistance to acetone. As used herein, “resistance to acetone” refers to evaluation according to JIS K5600-6-1: 1999 (Method 3) and determination as being “resistant”. Detailed items are defined as follows.

  Test plate: Use a film.

Dimensions: 30mm x 30mm
Thickness: 20 μm
Test solution: Acetone Dropping point: Center of test plate Cleaning after test: Flowing water period: 30 minutes Evaluation: If any of the following (a) to (c) is met, it is judged as “no resistance”. If it does not correspond to any of the above, it is judged that there is tolerance.

  (A) When placed on a horizontal table, the difference between the lowest position and the highest position of the test plate is 3 mm or more.

  (B) The test plate is wound into a roll and forms a roll of one or more rounds.

  (C) The haze after the test is 1% or more larger than the haze before the test.

  The film formation for preparing the test plate is made by the following procedure.

        (1) The resin is dissolved in N-methyl-2-pyrrolidone.

      (2) The polymer solution obtained in (1) is developed on the support plate.

  (3) The polymer solution developed on the support plate is dried at 120 ° C./5 min.

  (4) The film is peeled off from the glass plate and fixed to a metal frame.

  (5) The film is heat-treated at 120 ° C. for 20 minutes and 300 ° C. for 1 minute.

  In order to improve the tolerance with respect to acetone, it can achieve by including the structural unit shown by chemical formula (I).

  In the aromatic polyamide film of the present invention, the average coefficient of thermal expansion from 100 ° C. to 200 ° C. in at least one direction is 0 ppm / ° C. or more and 40 ppm / ° C. or less. More preferably, it is 0 ppm / ° C. or more and 30 ppm / ° C. or less. More preferably, they are 0 ppm / degrees C or more and 25 ppm / degrees C or less. When the average coefficient of thermal expansion from 100 ° C. to 200 ° C. in at least one direction is less than 0 ppm / ° C. or exceeds 40 ppm / ° C., a thin film transistor (indium-doped tin oxide (ITO)) is laminated. When producing (TFT), curling, cracking, and misalignment may occur. In order for the average thermal expansion coefficient from 100 ° C. to 200 ° C. in at least one direction to be 0 ppm / ° C. or more and 40 ppm / ° C. or less, it can be achieved by including the structural unit represented by the chemical formula (III). More preferably, when the molar fraction of the structural unit represented by the chemical formula (III) is 1, l ≧ 50.

  The aromatic polyamide contained in the aromatic polyamide film of the present invention preferably contains a structural unit derived from a silicon compound represented by the chemical formula (II).

R ¹ : methyl or phenyl (however, structural units having these groups may be mixed in the molecule)
R ² : methyl or phenyl (however, structural units having these groups may be mixed in the molecule)
R ³ : H, OH, methyl, ethyl, methoxy, or ethoxy (however, structural units having these groups may be mixed in the molecule)
R ⁴ : H, OH, methyl, ethyl, methoxy, or ethoxy (however, structural units having these groups may be mixed in the molecule)
R ⁵ : H, OH, methyl, ethyl, methoxy, or ethoxy (however, structural units having these groups may be mixed in the molecule)
R ⁶ : H, OH, methyl, ethyl, methoxy, or ethoxy (however, structural units having these groups may be mixed in the molecule)
Aromatic polyamides having a 2,2′-dimethyl-biphenyl structure as disclosed in Patent Documents 3 to 5 have strong absorption of light in the visible light region and light transmittance of light in the visible light region. It was low. On the other hand, the aromatic polyamide contained in the aromatic polyamide film of the present invention introduces a 2,2′-dimethyl-biphenyl structure by introducing a structural unit derived from the silicon compound represented by the chemical formula (II). It has been found that even an aromatic polyamide (film) can improve the light transmittance of light in the visible light region. As for this phenomenon, an improvement in light transmittance is not observed only by adding a silicon compound having excellent light transmittance to an organic solvent solution in which an aromatic polyamide having a 2,2′-dimethyl-biphenyl structure is dissolved. It is considered to be a specific phenomenon that is manifested by polymerizing an aromatic polyamide into which a 2,2′-dimethyl-biphenyl structure is introduced in an organic solvent solution in which a silicon compound is dissolved. From this, it is assumed that the light transmittance of light in the visible light region is improved because the structural unit derived from the silicon compound is incorporated into the polymer structure. The silicon compound used in the present invention is preferably an organic silicon compound, and more preferably a silicon compound represented by the above chemical formula (II).

Further, the silicon compound represented by the formula (II), for R ¹ and R ² are excellent in compatibility with certain the aromatic polyamide phenyl, preferred. R ³ to R ⁶ are preferably H, OH, and ethyl because they are excellent in compatibility with the aromatic polyamide and in the stability of the polymer solution.

In addition, R < ³ > -R < ⁶ > of Chemical formula (II) will be couple | bonded with an aromatic polyamide structural unit partly or entirely by being taken in into a polymer structure.

  The Young's modulus of the aromatic polyamide film of the present invention is preferably 5 GPa or more in at least one direction in the measurement based on JIS-K7127-1999. More preferably, it is 6 GPa or more, More preferably, it is 7 GPa or more. When the Young's modulus is less than 5 GPa, the handling property tends to be lowered. In addition, the Young's modulus can be further improved by stretching at the time of film formation. However, if the stretching is too strong, the elongation decreases, so that the upper limit of the Young's modulus is about 20 GPa. In order to set the Young's modulus in at least one direction to 5 GPa or more, it can be achieved by including a structural unit represented by the chemical formula (III). More preferably, when the molar fraction of the structural unit represented by the chemical formula (III) is 1, l ≧ 50.

The aromatic polyamide of the present invention contains structural units represented by the chemical formulas (III) and (IV), and the molar fractions of the structural units represented by the chemical formulas (III) and (IV) are 1 and m, respectively. It is preferable that the following expressions (4) and (5) are satisfied. The ratio of the molar fraction l is more preferably the following formula (6), and most preferably the following formula (7) is satisfied.
When l is smaller than 50, the average thermal expansion coefficient from 100 ° C. to 200 ° C. may increase.

50 ≦ l ≦ 100 (4)
95 ≦ l + m ≦ 100 (5)
60 ≦ l ≦ 100 (6)
65 ≦ l ≦ 100 (7)

R ⁷ : Any aromatic group (however, two or more types of aromatic groups may be present in the molecule)
R ⁸ : structural unit represented by chemical formula (V) (however, structural units having these groups may be mixed in the molecule)
R ⁹ : Any aromatic group (however, two or more types of aromatic groups may be present in the molecule)

The structural unit represented by R ⁸ is appropriately selected from the structural units represented by the chemical formula (V), but is more preferably selected from the structural units represented by the chemical formula (VI). Furthermore, it is more preferable to select the structural unit represented by the chemical formula (VII) because transparency and resistance to acetone are improved.

In the structural units represented by the chemical formulas (III) and (IV), R ⁷ and R ⁹ can select any aromatic group, but by selecting the structural unit represented by the chemical formula (VIII), the average This is preferable from the viewpoint that the thermal expansion coefficient can be reduced and the Young's modulus can be improved.

  These structures can be selected as appropriate, but if only one of the structural units is introduced into the polymer structure, the packing of the molecular chains progresses and the polymer may precipitate from the organic solvent during the polymerization, and the degree of polymerization may not increase. Therefore, it is more preferable to mix these structures in the polymer structure.

  Specifically, it is preferable that the following formulas (8) to (10) are satisfied when the molar fractions of the respective structural units represented by the chemical formula (IX) are a, b, and c, respectively.

50 ≦ a ≦ 100 (8)
0 ≦ b ≦ 50 (9)
98 ≦ a + b + c ≦ 100 (10)
Next, although the example which manufactures the aromatic polyamide film in this invention is demonstrated, of course, this invention is not limited to this.

  Various methods can be used as a method for obtaining a polyamide solution, that is, a film forming stock solution. For example, a low temperature solution polymerization method, an interfacial polymerization method, a melt polymerization method, a solid phase polymerization method, and the like can be used. When it is obtained from a low temperature solution polymerization method, that is, from carboxylic acid dichloride and diamine, it is synthesized in an aprotic organic polar solvent.

  Examples of the carboxylic acid dichloride include terephthalic acid dichloride, 2chloro-terephthalic acid dichloride, isophthalic acid dichloride, naphthalene dicarbonyl chloride, biphenyl dicarbonyl chloride, terphenyl dicarbonyl chloride, and the like, and most preferably 4,4′-biphenyl. Carboxylic acid dichloride, terephthalic acid dichloride, and isophthalic acid dichloride are used.

  Examples of the diamine include 4,4′-diaminodiphenyl ether, 3,4′-diaminodiphenyl ether, 4,4′-diaminodiphenyl sulfone, 3,3′-diaminodiphenyl sulfone, and 2,2′-ditrifluoromethyl-4,4. '-Diaminobiphenyl, 9,9-bis (4-aminophenyl) fluorene, 9,9-bis (4-amino-3-methylphenyl) fluorene, bis [4- (4-aminophenoxy) phenyl] sulfone, bis [4- (3-aminophenoxy) phenyl] sulfone, 2,2-bis [4- (4-aminophenoxy) phenyl] propane, 2,2-bis (4-aminophenyl) hexafluoropropane, O-tolidine, 2,2′-dimethyl-4,4′-diaminobiphenyl (m-tolidine), 1,1-bis (4-a Minophenyl) cyclohexane, 3,3 ', 5,5'-tetramethylbenzidine and the like are preferable, and 3,3'-diaminodiphenylsulfone and m-tolidine are preferable.

  Polyamide solution uses acid dichloride and diamine as monomers to produce hydrogen chloride as a by-product. When neutralizing this, inorganic neutralizers such as calcium hydroxide, calcium carbonate, lithium carbonate, and ethylene Organic neutralizers such as oxide, propylene oxide, ammonia, triethylamine, triethanolamine, diethanolamine are used. The reaction between isocyanate and carboxylic acid is carried out in an aprotic organic polar solvent in the presence of a catalyst.

  When performing polymerization using two or more kinds of diamines, diamines are added one by one, 10 to 99 mol% of acid dichloride is added to the diamine and reacted, and then another diamine is added, Further, a stepwise reaction method in which acid dichloride is added and reacted, a method in which all diamines are mixed and added, and then acid dichloride is added and reacted can be used. Similarly, when two or more kinds of acid dichlorides are used, a stepwise method, a method of simultaneously adding them, and the like can be used. In any case, the molar ratio of all diamines to all acid dichlorides is preferably 49:51 to 51:49. If this value is exceeded, it may be difficult to obtain a polymer solution suitable for molding.

  In the present invention, the aromatic polyamide and the silicon compound are obtained by a method of polymerizing the aromatic polyamide in an organic solvent in which the silicon compound is dissolved. Preferably, it includes a step of polymerizing the aromatic polyamide in the presence of the silicon compound represented by the chemical formula (II). Unlike simple mixing, by polymerizing an aromatic polyamide in the presence of a silicon compound, the hydroxyl and alkoxy groups of some silicon compounds react with acid dichloride and are added to the molecular chain of the aromatic polyamide. Or is considered to be incorporated. This is considered to improve the light transmittance of the aromatic polyamide itself, increase the compatibility between the silicon compound and the aromatic polyamide, and reduce the haze.

  When diamine and dicarboxylic acid dichloride are used as raw materials, they are amine terminals or carboxylic acid terminals depending on the composition ratio of the raw materials. Alternatively, the end capping may be performed with other amine, carboxylic acid chloride, or carboxylic acid anhydride.

  Compounds used for end-capping include benzoyl chloride, substituted benzoyl chloride, acetic anhydride, 5-norbornene-2,3-dicarboxylic anhydride, 4-ethynylaniline, 4-phenylethynylphthalic anhydride, maleic anhydride, etc. It can be illustrated.

  Examples of the aprotic polar solvent used in the production of polyamide include sulfoxide solvents such as dimethyl sulfoxide and diethyl sulfoxide, formamide solvents such as N, N-dimethylformamide and N, N-diethylformamide, and N, N. -Acetamide solvents such as dimethylacetamide, N, N-diethylacetamide, pyrrolidone solvents such as N-methyl-2-pyrrolidone, N-vinyl-2-pyrrolidone, phenol, o-, m- or p-cresol, xylenol , Phenolic solvents such as halogenated phenols and catechols, hexamethylphosphoramide, γ-butyrolactone, etc., and these are preferably used alone or as a mixture. Charcoal The use of hydrogen is also possible. Furthermore, for the purpose of accelerating the dissolution of the polymer, 50% by mass or less of an alkali metal or alkaline earth metal salt can be added to the solvent.

The aromatic polyamide film of the present invention may contain 10% by mass or less of an inorganic or organic additive for the purpose of surface formation and processability improvement. Examples of additives for surface formation include inorganic particles such as SiO ₂ , TiO ₂ , Al ₂ O ₃ , CaSO ₄ , BaSO ₄ , CaCO ₃ , carbon black, carbon nanotubes, fullerene, zeolite, and other metal fine powders. Etc. Preferred organic particles include, for example, particles made of an organic polymer such as crosslinked polyvinylbenzene, crosslinked acrylic, crosslinked polystyrene, polyester particles, polyimide particles, polyamide particles, and fluororesin particles, or the above organic polymer on the surface. Inorganic particles that have been subjected to treatment such as coating may be mentioned.

  Next, film formation will be described.

  The film-forming stock solution prepared as described above is formed into a film by a so-called solution casting method. The solution casting method includes a dry-wet method, a dry method, a wet method, etc., and any method may be used, but here, the dry-wet method will be described as an example.

  In the case of forming a film by a dry-wet method, the stock solution is extruded from a die onto a support such as a drum, an endless belt, or a support film to form a thin film, and then dried until the thin film layer has self-holding property. Drying conditions can be performed in the range of room temperature to 220 ° C. and within 60 minutes, for example. Further, the smoother the surface of the drum, endless belt, and support film used in this drying step, the smoother the surface. The film (sheet) that has been subjected to the dry process is peeled off from the support and introduced into the wet process, where desalting and solvent removal are performed, and further, stretching, drying, and heat treatment are performed to form a film. The heat treatment temperature is preferably a high temperature of 280 ° C. or higher, more preferably 300 ° C. or higher, further preferably 320 ° C. or higher, more preferably 340 ° C. or higher. If it exceeds 400 ° C, it may decompose. The heat treatment time is preferably 30 seconds or longer, more preferably 1 minute or longer, still more preferably 3 minutes or longer, more preferably 5 minutes or longer. The heat treatment is preferably performed in an inert atmosphere such as nitrogen or argon.

  The aromatic polyamide film of the present invention can also be used as a laminated film. As the production method, it is preferable to use a dry-wet process of a solution film-forming method in which an organic solvent solution of a resin is extruded from a die and cast on a support, and is dried, solvent-extracted and heat-set, and a laminated film is produced In this case, it is preferred to laminate the organic solvent solution of the aromatic polyamide of the present invention into a laminated film at any stage of this process. More preferably, the organic solvent solution of the resin and the organic solvent solution of the aromatic polyamide of the present invention are laminated before the die or in the die and cast onto the support. Examples of a method of laminating in front of the die include a method of laminating using a laminating apparatus called a pinole, a composite tube, or a feed block. Moreover, as a method of laminating in the die, a method using a multilayer die or a multi-manifold die can be mentioned. Resin organic solvent solutions and aromatic polyamide organic solvent solutions often have different solution viscosities. For this reason, it may be difficult to obtain a good laminated structure by a method of laminating before a die such as pinol. For this reason, it is preferable to laminate | stack within a nozzle | cap | die using a multi-manifold nozzle | cap | die.

  As a method for producing a film, both the longitudinal direction of the film (the film forming and conveying direction; hereinafter referred to as MD) and the width direction (the direction perpendicular to the longitudinal direction in the film plane; hereinafter referred to as TD) are 1. It is preferable to draw at a draw ratio of from 05 times to 2.50 times. The draw ratio in the MD direction is preferably 1.05 times to 1.50 times, more preferably 1.05 times to 1.30 times, still more preferably 1.05 times to 1.20 times, most preferably It is 1.06 times or more and 1.15 times or less. The draw ratio in the TD direction is preferably 1.05 times or more and 2.50 times or less, more preferably 1.10 times or more and 2.00 times or less, still more preferably 1.15 times or more and 1.50 times or less, and most preferably 1.20 times or more and 1.30 times or less. Further, the draw ratio in the TD direction is preferably 1.0 times or more and 1.5 times or less with respect to the draw ratio in the MD direction. More preferably, it is 1.05 times or more and 1.20 times or less, and most preferably 1.1 times or more and 1.15 times or less.

  The structure of the film is determined by its raw materials. In the case of conducting a structural analysis of a film whose raw material is unknown, mass spectrometry, analysis by a nuclear magnetic resonance method, spectroscopic analysis, or the like can be used.

  In the film, the thickness is preferably 0.01 μm to 1,000 μm. More preferably, it is 1 μm to 100 μm. More preferably, they are 2 micrometers to 50 micrometers, More preferably, they are 2 micrometers to 30 micrometers, More preferably, they are 2 micrometers to 20 micrometers. When the thickness of the film exceeds 1,000 μm, the light transmittance may be lowered. Moreover, if the thickness of the film is less than 0.01 μm, the workability may be deteriorated even in the case of an organic-inorganic composite containing a highly rigid aromatic polyamide. Needless to say, the thickness of the film should be appropriately selected depending on the application.

  It is preferable that the film of the present invention has a Young's modulus in at least one direction of 4 GPa or more because it can resist the force applied at the time of processing and at the time of use, and the flatness is further improved. Further, when the Young's modulus in at least one direction is 4 GPa or more, the film can be thinned.

  If the Young's modulus in all directions is less than 4 GPa, deformation may occur during processing. Moreover, although there is no upper limit in Young's modulus, when Young's modulus exceeds 20 GPa, the toughness of a film will fall and film formation and a process may become difficult. The Young's modulus is more preferably 6 GPa or more in at least one direction, and still more preferably 6.5 GPa or more in at least one direction.

  In addition, it is preferable that the ratio of the Young's modulus (Em) to the Young's modulus (Ep) in a direction perpendicular to the Young's modulus, which is Em / Ep, is 1.1 to 3, since the cutting property during processing is improved. More preferably, it is 1.2-2.5, More preferably, it is 1.5-2.5. When Em / Ep exceeds 3, it may be easy to break.

  The film of the present invention described above is a display material, display material substrate, circuit substrate, photoelectric composite circuit substrate, optical waveguide substrate, semiconductor mounting substrate, multilayer laminated circuit substrate, transparent conductive film, retardation film, touch panel, capacitor, printer ribbon It is preferably used for various applications such as acoustic diaphragms, solar cells, optical recording media, base films for magnetic recording media, packaging materials, adhesive tapes, adhesive tapes, and decorative materials.

  Regarding display materials, glass is generally used as a display material substrate. However, when the film of the present invention is used as a display material substrate, it is possible to obtain a display material having great merits such as thinning, lightening, and no cracking. . The type of the display material of the present invention is not particularly limited, but is preferably a thin film, a thin film display that is advantageous in light weight, or a thin film display. Examples of the thin film display include a liquid crystal display, an organic EL display, an inorganic EL display, a plasma display, a field emission display, and electronic paper. In addition, as a film with a special shape, prism sheets, optical fibers and optical waveguides, lenses, microlens arrays, optical filters, antireflection films, flattening films, coating agents for other materials, and other materials are bonded together. It can be suitably used for laminated products and molded products.

  The present invention will be described more specifically with reference to the following examples.

  The measurement method of physical properties and the evaluation method of effects in the present invention were performed according to the following methods.

(1) Light transmittance of 385 nm light It measured using the following apparatus and computed using the following formula.

Transmittance (%) = (Tr1 / Tr0) × 100
However, Tr1 is the intensity | strength of the light which passed the sample, Tr0 is the intensity | strength of the light which passed the air of the same distance except not passing a sample.

Apparatus: UV measuring instrument U-3410 (manufactured by Hitachi Instruments)
Wavelength range: 300 nm to 800 nm (of which the value at a wavelength of 385 nm is used)
Measurement speed: 120 nm / min Measurement mode: Transmission (2) Resistance to acetone Evaluation is performed according to JIS K5600-6-1: 1999 (Method 3). Detailed items are defined as follows.

            Test plate: Use a film.

Dimensions: 30mm x 30mm
Thickness: 20 μm
Test solution: Acetone Dropping point: Center of test plate Cleaning after test: Flowing water period: 30 minutes Evaluation: If any of the following (a) to (c) is met, it is judged as “no resistance”. If it does not correspond to any of the above, it is judged that there is tolerance.

  (A) When placed on a horizontal table, the difference between the lowest position and the highest position of the test plate is 3 mm or more.

  (B) The test plate is wound into a roll and forms a roll of one or more rounds.

  (C) The haze after the test is 1% or more larger than the haze before the test.

  The film formation for preparing the test plate is made by the following procedure.

        (1) The resin is dissolved in N-methyl-2-pyrrolidone.

      (2) The polymer solution obtained in (1) is developed on the support plate.

  (3) The polymer solution developed on the support plate is dried at 120 ° C./5 min.

  (4) The film is peeled off from the glass plate and fixed to a metal frame.

  (5) The film is heat-treated at 120 ° C. for 20 minutes and 300 ° C. for 1 minute.

(3) Average thermal expansion coefficient The average thermal expansion coefficient was measured in the temperature lowering process after the temperature was raised to 250 ° C. according to JIS K7197-1991. When the initial sample length at 25 ° C. and 75 RH% is L0, the sample length at the temperature T1 is L1, and the sample length at the temperature T2 is L2, the average thermal expansion coefficient from T1 to T2 was obtained by the following equation.

  Note that T2 = 100 (° C.), T1 = 200 (° C.), and L0 = 15 mm.

Thermal expansion coefficient (ppm / ° C.) = (((L2-L1) / L0) / (T2-T1)) × 10 ⁶
Temperature increase / decrease rate: 5 ° C / min
Sample width: 4mm
Load: 44.5 mN when the film thickness is 10 μm
The load is changed in proportion to the film thickness.

Weight = 44.5 (mN) × d (μm) / 10 (μm)
d (μm): film thickness (4) Young's modulus Measured at a temperature of 23 ° C. and a relative humidity of 65% using Robot Tensilon RTA (manufactured by Orientec). The test piece was a sample having a width of 10 mm and a length of 50 mm in the TD direction, where the film forming direction or the moving direction of the bar coater was the MD direction, and the direction orthogonal thereto was the TD direction. The tensile speed is 300 mm / min. However, the point where the load passed 1 N after the start of the test was taken as the origin of elongation.

(5) Raw material The following were used for the raw material used for the aromatic polyamide of this invention. The structural formulas of the diamine and acid dichloride used are shown in chemical formula (X).

[Diamine]
Diamine 1: m-tolidine (manufactured by Wakayama Seika Kogyo Co., Ltd.)
Diamine 2: 3,3′-diaminodiphenylsulfone (manufactured by Tokyo Chemical Industry Co., Ltd.)
Diamine 3: 1,1-bis (4-aminophenyl) cyclohexane (manufactured by Taoka Chemical Co., Ltd.)
Diamine 4: 2,2′-ditrifluoromethyl-4,4′-diaminobiphenyl (Toray Fine Chemical Co., Ltd.)
Diamine 5: 4,4′-diaminodiphenylsulfone (manufactured by Wakayama Seika Kogyo Co., Ltd.)
[Acid dichloride]
Acid dichloride 1: terephthalic acid dichloride (manufactured by Tokyo Chemical Industry Co., Ltd.)
Acid dichloride 2: Biphenyl dicarbonyl chloride (Toray Fine Chemical Co., Ltd.)
Acid dichloride 3: Isophthalic acid dichloride (manufactured by Tokyo Chemical Industry Co., Ltd.)
[Silicon compound]
Silicon compound 1: PPSQ-E SR-23 (manufactured by Konishi Chemical Co., Ltd.)

(Reference Example 1)
Anhydrous lithium chloride (3.38 g) is placed in a 300 ml three-necked flask equipped with a stirrer and heated to 110 ° C. with stirring under a nitrogen stream to dry. After cooling to 30 ° C., 6.40 g of diamine 4, 1.24 g of diamine 5 and 119 ml of N-methyl-2-pyrrolidone were added and stirred under a nitrogen atmosphere. Next, the mixture was cooled to 0 ° C., and acid dichloride (21.40 g) was added in 5 portions over 30 minutes, and the mixture was stirred for 60 minutes after completion of the addition. Next, 4.06 g of acid dichloride 1 was added in 5 portions over 30 minutes. After further stirring for 60 minutes, hydrogen chloride generated by the reaction was neutralized with lithium carbonate to obtain a polymer solution. The polymer obtained here is referred to as Resin B.

Example 1
In a 300 ml three-necked flask equipped with a stirrer, 2.70 g of anhydrous lithium chloride is placed, heated to 110 ° C. with stirring under a nitrogen stream, and dried. After cooling to 30 ° C., 1.80 g of PPSQ-ESR-23, 2.65 g of diamine 1, 3.10 g of diamine 2 and 76 ml of N-methyl-2-pyrrolidone were added and stirred under a nitrogen atmosphere. The diamine and the silicon compound were dissolved in a solvent until they could not be visually confirmed. Next, the mixture was cooled to 0 ° C., 5.08 g of acid dichloride 1 was added in 5 portions over 30 minutes, and the mixture was stirred for 60 minutes after completion of the addition. Next, hydrogen chloride generated by the reaction was neutralized with lithium carbonate to obtain a silicon-containing aromatic polyamide polymer solution in which an aromatic polyamide structural unit and a structural unit derived from a silicon compound were combined. The polymer obtained here is referred to as Resin A.

  A part of the obtained polymer solution was taken on a glass plate, and a uniform film was formed using a bar coater. This was heated at 120 ° C. for 7 minutes to obtain a self-holding film. The obtained film was peeled off from the glass plate, fixed to a metal frame, washed with running water for 10 minutes, and further subjected to heat treatment at 280 ° C. for 3 minutes to obtain an aromatic polyamide film (dry and wet film formation). The physical properties of the obtained film were measured and are shown in Table 1.

(Example 2)
In a 300 ml three-necked flask equipped with a stirrer, 3.24 g of anhydrous lithium chloride is put, heated to 110 ° C. while being stirred under a nitrogen stream, and dried. After cooling to 30 ° C., stirred PPSQ- E SR-23 2.16g, diamine 1 3.18 g, diamine 2 3.72 g, under a nitrogen atmosphere put N- methyl-2-pyrrolidone 114 ml, The diamine and the silicon compound were dissolved in a solvent until they could not be visually confirmed. Subsequently, it cooled to 0 degreeC and added acid dichloride 3 3.05g in 5 steps over 30 minutes, and stirred for 60 minutes after completion | finish of addition. Next, 3.05 g of acid dichloride 1 was added in 5 portions over 30 minutes. After further stirring for 60 minutes, hydrogen chloride generated by the reaction was neutralized with lithium carbonate to obtain a silicon-containing aromatic polyamide polymer solution in which the aromatic polyamide structural unit and the structural unit derived from the silicon compound were combined. .

  A part of the obtained polymer solution was taken on a glass plate, and a uniform film was formed using a bar coater. This was heated at 120 ° C. for 7 minutes to obtain a self-holding film. The obtained film was peeled off from the glass plate, fixed to a metal frame, washed with running water for 10 minutes, and further subjected to heat treatment at 280 ° C. for 3 minutes to obtain an aromatic polyamide film (dry and wet film formation). The physical properties of the obtained film were measured and are shown in Table 1.

(Example 3)
2.76 g of anhydrous lithium chloride is placed in a 300 ml three-necked flask equipped with a stirrer, and heated to 110 ° C. with stirring under a nitrogen stream to dry. After allowing to cool to 30 ° C., 2.76 g of PPSQ-ESR-23, 3.72 g of diamine 1, 1.86 g of diamine 2 and 94 ml of N-methyl-2-pyrrolidone were added and stirred under a nitrogen atmosphere. The diamine and the silicon compound were dissolved in a solvent until they could not be visually confirmed. Next, the mixture was cooled to 0 ° C., and 1.37 g of acid dichloride 2 was added in 5 portions over 30 minutes, followed by stirring for 60 minutes after the addition was completed. Next, 4.06 g of acid dichloride 1 was added in 5 portions over 30 minutes. After further stirring for 60 minutes, hydrogen chloride generated by the reaction was neutralized with lithium carbonate to obtain a silicon-containing aromatic polyamide polymer solution in which the aromatic polyamide structural unit and the structural unit derived from the silicon compound were combined. .

  A part of the obtained polymer solution was taken on a glass plate, and a uniform film was formed using a bar coater. This was heated at 120 ° C. for 7 minutes to obtain a self-holding film. The obtained film was peeled off from the glass plate, fixed to a metal frame, washed with running water for 10 minutes, and further subjected to heat treatment at 280 ° C. for 3 minutes to obtain an aromatic polyamide film (dry and wet film formation). The physical properties of the obtained film were measured and are shown in Table 1.

Example 4
4.15 g of anhydrous lithium chloride is placed in a 300 ml three-necked flask equipped with a stirrer, and heated to 110 ° C. with stirring under a nitrogen stream to dry. After allowing to cool to 30 ° C., 4.15 g of PPSQ-E SR-23, 5.50 g of diamine 1, 2.96 g of diamine 3, and 144 ml of N-methyl-2-pyrrolidone were added and stirred under a nitrogen atmosphere. The diamine and the silicon compound were dissolved in a solvent until they could not be visually confirmed. Subsequently, it cooled to 0 degreeC and added acid dichloride 2 2.07g in 30 times over 30 minutes, and stirred for 60 minutes after completion | finish of addition. Next, 6.01 g of acid dichloride 1 was added in 5 portions over 30 minutes. After further stirring for 60 minutes, hydrogen chloride generated by the reaction was neutralized with lithium carbonate to obtain a silicon-containing aromatic polyamide polymer solution in which the aromatic polyamide structural unit and the structural unit derived from the silicon compound were combined. .

  A part of the obtained polymer solution was taken on a glass plate, and a uniform film was formed using a bar coater. This was heated at 120 ° C. for 7 minutes to obtain a self-holding film. The obtained film was peeled off from the glass plate, fixed to a metal frame, washed with running water for 10 minutes, and further subjected to heat treatment at 280 ° C. for 3 minutes to obtain an aromatic polyamide film (dry and wet film formation). The physical properties of the obtained film were measured and are shown in Table 1.

(Example 5)
The resin A obtained in Example 1 and the resin B obtained in Reference Example 1 were laminated to form an A / B / A laminated structure using a multi-manifold die, and cast on an endless belt at 120 ° C. The polymer solution was then dried until it was self-supporting and peeled off from the endless belt. Next, the solvent-containing film was washed with water at 40 ° C. to remove the solvent. Furthermore, it heat-processed in the drying furnace of 340 degreeC, and obtained the film. The film thickness of each layer of A | B | A was 2 μm | 10 μm | 2 μm. The physical properties of the obtained film were measured and are shown in Table 2.

(Comparative Example 1)
Polymerization and film formation were carried out in the same manner as in Example 1 except that no silicon compound was added. The physical properties of the obtained film were measured and are shown in Table 1.

(Comparative Example 2)
1.80 g of PPSQ-ESR-23 was added to the polymer solution obtained in Comparative Example 1 and the mixture was stirred for 2 hours to obtain a polymer solution in which an aromatic polyamide and a silicon compound were mixed. Using the obtained polymer solution, a film was formed in the same manner as in Example 1, and the physical properties of the obtained film were measured.

Claims (4)

Including a silicon-containing aromatic polyamide in which an aromatic polyamide structural unit having a structural unit represented by chemical formula (I) and a structural unit derived from a silicon compound represented by chemical formula (II) are combined, An aromatic polyamide film satisfying all of (3).
(1) The light transmittance of light having a wavelength of 385 nm is 15% or more.
(2) Resistant to acetone.
(3) The average coefficient of thermal expansion from 100 ° C. to 200 ° C. in at least one direction is 0 ppm / ° C. or more and 40 ppm / ° C. or less.

R ¹ : methyl or phenyl (however, structural units having these groups may be mixed in the molecule)
R ² : methyl or phenyl (however, structural units having these groups may be mixed in the molecule)
R ³ : H, OH, methyl, ethyl, methoxy, or ethoxy (however, structural units having these groups may be mixed in the molecule)
R ⁴ : H, OH, methyl, ethyl, methoxy, or ethoxy (however, structural units having these groups may be mixed in the molecule)
R ⁵ : H, OH, methyl, ethyl, methoxy, or ethoxy (however, structural units having these groups may be mixed in the molecule)
R ⁶ : H, OH, methyl, ethyl, methoxy, or ethoxy (however, structural units having these groups may be mixed in the molecule) The aromatic polyamide film according to claim 1, wherein the Young's modulus in at least one direction is 5 GPa or more. When the aromatic polyamide contains structural units represented by the chemical formulas (III) and (IV) and the molar fractions of the structural units represented by the chemical formulas (III) and (IV) are 1 and m, respectively, the following formula ( The aromatic polyamide film according to claim 1 or 2 , which satisfies 4) and (5).
50 ≦ l ≦ 100 (4)
95 ≦ l + m ≦ 100 (5)

R ⁷ : Any aromatic group (however, two or more types of aromatic groups may be present in the molecule)
R ⁸ : structural unit represented by chemical formula (V) (however, structural units having these groups may be mixed in the molecule)
R ⁹ : Any aromatic group (however, two or more types of aromatic groups may be present in the molecule).

The manufacturing method of the aromatic polyamide film in any one of Claims 1-3 including the process of superposing | polymerizing aromatic polyamide in presence of the silicon compound shown by Chemical formula (II).