JP5853469B2 - Totally aromatic polyamide film, method for producing the same, and laminate - Google Patents

Description

  The present invention has high reflectance of visible light, particularly light at a wavelength around 425 nm, high whiteness, and satisfies VTM-0 in the UL94 standard combustion test without containing a flame retardant, Furthermore, the present invention relates to a highly heat-resistant wholly aromatic polyamide film and a method for producing the same. Further, the use of the wholly aromatic polyamide film of the present invention is not limited to these, but a light emitting diode (hereinafter abbreviated as LED), in particular, a mounting substrate for an LED element, a reflective material for a white LED, and an LED are mounted. It is suitably used as a metal laminated base material such as copper, or a white coverlay film bonded onto a flexible substrate or a substrate.

  LEDs are used in various applications such as home general lighting, in-vehicle lighting, displays and backlights for mobile phones, taking advantage of long life and low power consumption. In recent years, thinning and weight reduction of these electronic devices has been demanded, and SMT (surface mounting technology) for mounting LED elements on the surface of electronic substrates has become widespread. Thus, when mounting an LED directly on an electronic substrate, it is necessary to efficiently extract the light from the LED element to the front surface, and the base material is required to have a high reflectance with light of the wavelength of the LED emission region. It is done. Not only that, it maintains low reflectivity even after high-temperature processes such as the thermosetting process of the sealing resin and the solder reflow process during mounting, and it does not cause deformation or swelling of the substrate. An expansion coefficient and high heat resistance are required, and further flame retardancy is also required.

  Conventionally, as a substrate film used for LED mounting, for example, Patent Literatures 1 to 4 are known. These documents disclose a resin composition in which a white pigment is blended with a transparent resin such as partially aromatic polyamide or semi-aromatic polyamide. In partially aromatic or semi-aromatic, the polymer structure has a bent structure. Since it has a large thermal expansion coefficient and low heat resistance, there has been a problem that in the solder reflow process at the time of LED mounting, swelling and deformation occur, or the reflectance decreases greatly. In addition, in order to impart heat resistance, generally a polymer structure containing a large amount of aromatic groups, such as wholly aromatic polyamides and polyimides, has high heat resistance, and swelling and deformation are not observed during the solder reflow process. Many aromatic polyamides and polyimides absorb visible light and are colored yellow or brown, so even when white pigments are added, they have low whiteness and low reflectance. Only obtained. Then, about polyimide, although the highly flexible aliphatic group, such as hydrocarbon, was introduce | transduced into the polymer structure, the white polyimide which mix | blended the white pigment with the colorless polyimide was developed (patent documents 5, 6), Since the polymer structure contains a large amount of bent structures, the coefficient of thermal expansion at high temperature is large, and not only the substrate is deformed during the mounting process, but also the problem is that the reflectance decreases due to resin coloring due to low heat resistance. there were.

  On the other hand, in addition to reflectance and high heat resistance, flame retardance is also required for LED mounting substrates. Patent Document 7 describes a flame-retardant polyamide, which is a halogenated bisimide compound or the like added as a flame retardant to a polyamide resin. In particular, a polyamide resin composition containing a halogen-based flame retardant may have poor light discoloration resistance, and is required to be flame retardant without adding a flame retardant.

JP 2008-182172 A JP 2002-294070 A JP 2004-75994 A JP 2010-1000068 A2 JP 2008-169237 A JP 2006-110999 A JP 2010-1365 A

  The present invention has been achieved as a result of studies to solve the above-described problems in the prior art. That is, an object of the present invention is to obtain a wholly aromatic polyamide having high reflectance, high whiteness, high heat resistance, flame retardancy, and low thermal expansion coefficient at high temperature.

The present invention for achieving the above object state, and are light reflectance of 70% or more wavelengths 425 nm, Ru der average thermal expansion coefficient of 200 ° C. from 100 ° C. is -10 ppm / ° C. or higher 20 ppm / ° C. or less total It is an aromatic polyamide film.

  According to the present invention, not only a high reflectance but also a high heat resistance and flame retardancy, and a film having a low thermal expansion coefficient can be obtained, so that it can be suitably used as a mounting substrate for LED elements. In addition, it has high heat resistance, flame retardancy, and low thermal expansion coefficient. Therefore, even in processes that require high heat of 200 ° C or higher, such as solder reflow process during LED mounting and thermosetting process of sealing resin, warping and deformation Therefore, it is particularly useful industrially because it has high productivity and can maintain high reflectivity even after a high temperature process.

  The wholly aromatic polyamide film of the present invention has a reflectance of 70% or more for light having a wavelength of 425 nm. More preferably, the reflectance of light having a wavelength of 425 nm is 75% or more. More preferably, the reflectance of light having a wavelength of 425 nm is 80% or more. More preferably, the reflectance of light having a wavelength of 425 nm is 85% or more. Most preferably, the reflectance of light having a wavelength of 425 nm is 90% or more. If the reflectance of light with a wavelength of 425 nm is 70% or more, it is preferable because the light emitted from the LED element can be used efficiently, but if the reflectance of light with a wavelength of 425 nm is lower than 70%, The light emitted from the LED element may not be used efficiently. In order to improve the reflectance, for example, when the molar fractions of the structural units represented by the chemical formulas (I) and (II) are 1 and m, respectively, the total fragrance satisfying the following formulas (1) to (3) It can be achieved by a group polyamide film.

R ¹ : A part or all of hydrogen in the aromatic ring is substituted with a substituent of any of —CF ₃ , —F, —OH, —OCH ₃ , —CH ₃ , —NO ₂ , —CN, and —Br. A para-oriented aromatic group.

R ² : Any para-oriented aromatic group.

R ³ : a para-oriented aromatic group having any one of a group containing S, a group containing P, a group containing Si, a halogenated hydrocarbon group, or a group containing an ether bond. However, in the molecule, structural units having these groups may be mixed.

R ⁴ : Any para-oriented aromatic group.

0 ≦ l ≦ 100 (1)
0 ≦ m ≦ 100 (2)
97 ≦ l + m ≦ 100 (3)
Also, increase the difference in refractive index between the resin and particles, increase the amount of particles added, keep the particle size within a predetermined range, or create a porous shape such as voids at the interface between the resin and particles or the resin itself. It can also be achieved by creating a gap.

The wholly aromatic polyamide film of the present invention preferably has an average thermal expansion coefficient of from −10 ppm / ° C. to 20 ppm / ° C. from 100 ° C. to 200 ° C. Thereby, not only can a deformation be suppressed even in a high-temperature process of LED mounting, but also a warp and a curl can be suppressed even when a laminate with a copper-coated polyimide is formed. More preferably, the average thermal expansion coefficient from 100 ° C. to 200 ° C. is from −5 ppm / ° C. to 16 ppm / ° C. More preferably, the average thermal expansion coefficient from 100 ° C. to 200 ° C. is from 0 ppm / ° C. to 16 ppm / ° C. More preferably, the average thermal expansion coefficient from 100 ° C. to 200 ° C. is from −5 ppm / ° C. to 13 ppm / ° C. When the average coefficient of thermal expansion from 100 ° C. to 200 ° C. is smaller than −10 ppm / ° C., the substrate may be deformed in a process in which a high temperature is applied during LED mounting. In addition, even when the average thermal expansion coefficient from 100 ° C. to 200 ° C. exceeds 20 ppm / ° C., the substrate may be deformed in a process in which a high temperature is applied during LED mounting. In order to make the average coefficient of thermal expansion from 100 ° C. to 200 ° C. from −10 ppm / ° C. to 20 ppm / ° C., the polymer structure must be wholly aromatic, and the aromatic group of the repeating unit is bonded to the para position. preferable. As used herein, “total aromatic” means that all of the repeating units in the polymer structure contain an aromatic component. When a polymer is obtained by polymerizing a diamine component and an acid dichloride component, a total aromatic polyamide polymer can be obtained by including an aromatic component in both of these components. However, by simply introducing aromatic groups into all repeating units, the polymer will be colored and a film with high reflectivity will not be obtained, so some or all of the hydrogen in the aromatic ring will be electronized. Substitution with a suction group is preferred. Electron withdrawing groups are believed to be able to inhibit the formation of charge transfer complexes within and between molecules of aromatic polyamides, improving the light transmittance of aromatic polyamides and lowering the YI value. Here, the electron-withdrawing group is a group showing a positive value in the Hammett's substituent constant. For example, —CF ₃ , —F, —OH, —OCH ₃ , —CH ₃ , —NO ₂ , —CN, It -br like but most preferably -CF _3.

  The wholly aromatic polyamide film of the present invention is preferable because it satisfies VTM-0 of the highest rank in the judgment of the combustion test defined in the United States Underwriters Laboratories Standard UL94.

  When the flame retardancy of VTM-1 or VTM-2, which is inferior to VTM-0, is shown, the necessity of containing a flame retardant increases, and the light discoloration resistance may decrease. Moreover, in order to satisfy VTM-0 prescribed | regulated to UL94, it can achieve by making all the repeating units of a polymer into an aromatic group. Further, it is more preferable that all of these aromatic groups are bonded at the para position.

  The wholly aromatic polyamide film of the present invention is preferable because it does not contain a flame retardant because an LED mounting substrate with a low environmental load can be obtained. Although the wholly aromatic polyamide film of the present invention satisfies VTM-0, which is flame retardant and does not contain a flame retardant, generally has a low flame retardant property such as polyethylene terephthalate. It is known to add flame retardant by adding an agent. However, since the flame retardant contains many substances such as halogen compounds, the environmental load may increase.

The wholly aromatic polyamide film of the present invention preferably has a decrease in reflectance of light having a wavelength of 425 nm after heating for 2 hours in air at 200 ° C. of 2.0% or less. Thereby, since the high reflectance can be maintained even after the LED mounting process at a high temperature and the thermosetting process of the sealing resin, the light emitted from the LED element can be used efficiently, which is preferable. More preferably, the decrease in reflectance of light having a wavelength of 425 nm after heating at 200 ° C. for 2 hours is 1.5% or less. More preferably, the decrease in reflectance of light having a wavelength of 425 nm after heating at 200 ° C. for 2 hours is 1.0% or less. In order to reduce the reflectance of light having a wavelength of 425 nm after heating at 200 ° C. for 2 hours to 2.0% or less, the polymer is allowed to contain inorganic particles and a coating film is formed on the surface of the contained inorganic particles. This can be achieved by forming. Examples of the coating film include SiO _2, Al ₂ O _{3, and} ZrO.

The wholly aromatic polyamide film of the present invention preferably has a whiteness of 70 or more. Thereby, the light emitted from the LED element can be used efficiently. More preferably, the whiteness is 75 or more. More preferably, the whiteness is 80 or more. More preferably, the whiteness is 85 or more. If the whiteness is lower than 70, the light emitted from the LED element may not be used efficiently. The whiteness of 70 or more can be achieved by suppressing the YI value of the wholly aromatic polyamide film in the state containing no inorganic particles to -5 or more and 5 or less. In order to suppress the YI value to −5 or more and 5 or less, it is preferable to substitute a part or all of the hydrogen of the aromatic ring with an electron withdrawing group, and examples of the substituent include —CF ₃ , —F, — OH, —OCH ₃ , —CH ₃ , —NO ₂ , —CN, —Br and the like may be mentioned, and most preferred is —CF ₃ .

  The wholly aromatic polyamide film of the present invention preferably has a total light transmittance of 50% or less. Thereby, the light emitted from the LED element can be used efficiently. More preferably, the total light transmittance is 40% or less. More preferably, the total light transmittance is 30% or less. If the total light transmittance is greater than 50%, the emitted light may be transmitted without being reflected, and the light may not be used efficiently. The total light transmittance of 50% or less can be achieved, for example, by containing 30% by mass or more of inorganic particles with respect to the total amount of the aromatic polyamide polymer. It can also be achieved by forming voids such as voids on the surface of the wholly aromatic polyamide film and inside the film.

It is preferable that the wholly aromatic polyamide film of the present invention is not deformed or swollen even after a 260 ° C. solder reflow process. The “260 ° C. solder reflow process” referred to here means that the wholly aromatic polyamide film of the present invention is allowed to stand in an atmosphere of 23 ° C. and 55% RH for 24 hours, or in an atmosphere of 40 ° C. and 90% RH. It means that the process of passing through an infrared heating furnace at 260 ° C. for 30 seconds is repeated three times after standing for a period of time. Furthermore, the 260 ° C. solder reflow process described above is carried out with the wholly aromatic polyamide film of the present invention alone, and the decrease in light reflectance at a wavelength of 425 nm before and after the 260 ° C. solder reflow process is 3.0%. The following is preferable. More preferably, it is 2.5% or less. Most preferably, it is 2.0% or less. In the wholly aromatic polyamide of the present invention, there is no deformation or swelling even after the solder reflow process at 260 ° C., and in order to reduce the reflectance of light at the wavelength of 425 nm to 3.0% or less, It is aromatic, and further, the aromatic group of the repeating unit is bonded to the para position. It can also be achieved by forming a coating film on the surface of the inorganic particles to be added. Examples of the coating film include SiO _2, Al ₂ O _{3, and} ZrO.

  The wholly aromatic polyamide film of the present invention preferably has a heat shrinkage of 1.5% or less when left in an oven at 200 ° C. under no tension and in air for 30 minutes. Thereby, not only can a deformation be suppressed even in a high-temperature process of LED mounting, but also a warp and a curl can be suppressed even when a laminate with a copper-coated polyimide film is used. More preferably, the thermal contraction rate is 1.0% or less. More preferably, it is 0.8% or less. For the wholly aromatic polyamide film of the present invention, in order to make the heat shrinkage ratio 1.5% or less when left in an oven at 200 ° C. under no tension and in air for 30 minutes, the polymer structure is made to be wholly aromatic. In addition, the aromatic group of the repeating unit is bonded to the para position. Moreover, the heat shrinkage rate can be suppressed to 1.5% or less by heat-treating the film at a high temperature of 200 ° C. or more and 500 ° C. or less.

  The wholly aromatic polyamide film of the present invention preferably has a thickness of 1 to 50 μm and a reflectance of light having a wavelength of 425 nm of 70% or more. A thinner film is preferable from the viewpoint of weight reduction and thinning. More preferably, the thickness is 1 μm or more and 40 μm or less, and the reflectance of light having a wavelength of 425 nm is 80% or more. More preferably, the thickness is 5 μm or more and 40 μm or less, and the reflectance of light having a wavelength of 425 nm is 85% or more. Even more preferably, the thickness is 5 μm or more and 30 μm or less, and the reflectance of light having a wavelength of 425 nm is 90% or more. Even more preferably, the thickness is 5 μm or more and 20 μm or less, and the reflectance of light having a wavelength of 425 nm is 90% or more. Most preferably, the thickness is 5 μm or more and 15 μm or less, and the reflectance of light having a wavelength of 425 nm is 90% or more.

  The inorganic particles to be contained are at least one selected from the group consisting of titanium oxide, zirconium oxide, calcium oxide, silicon oxide, zinc oxide, aluminum oxide, zinc sulfide, calcium sulfate, barium sulfate, barium titanate and strontium titanate. It is preferable that

  Moreover, as a method of forming a void on the film surface, it is preferable to manufacture by a manufacturing method having the following steps i) to iii).

    i) An organic solvent solution (U) is spread on a support plate.

ii) A liquid (e) containing 10% by mass or more of water is brought into contact with the organic solvent solution (U) on the support plate for 2 minutes or more. Alternatively, after introducing the organic solvent solution (U) on the support plate into a temperature-controlled and humidity-controlled environment having a temperature of 5 ° C. or more and 95 ° C. or less and a relative humidity of 50% or more and 100% or less, water is added. A liquid containing 10% by mass or more is brought into contact for 2 minutes or more.
iii) Heat at a temperature of 200 ° C. to 500 ° C. for 10 seconds to 10 minutes.

  In addition, when a film thickness is less than 1 micrometer, a reflectance and whiteness may fall. Moreover, handling property may fall.

  The wholly aromatic polyamide film of the present invention is a wholly aromatic material satisfying the following formulas (1) to (3) when the molar fractions of the structural units represented by the chemical formulas (I) and (II) are 1 and m, respectively. It is preferable that a group polyamide film and inorganic particles are included.

R ¹ : A part or all of hydrogen in the aromatic ring is substituted with a substituent of any of —CF ₃ , —F, —OH, —OCH ₃ , —CH ₃ , —NO ₂ , —CN, and —Br. A para-oriented aromatic group.

R ² : Any para-oriented aromatic group.

R ³ : a para-oriented aromatic group having any one of a group containing S, a group containing P, a group containing Si, a halogenated hydrocarbon group, or a group containing an ether bond. However, in the molecule, structural units having these groups may be mixed.

R ⁴ : Any para-oriented aromatic group.

0 ≦ l ≦ 100 (1)
0 ≦ m ≦ 100 (2)
97 ≦ l + m ≦ 100 (3)
Further, selected from the group consisting of wholly aromatic polyamide (A) and titanium oxide, zirconium oxide, calcium oxide, silicon oxide, zinc oxide, aluminum oxide, zinc sulfide, calcium sulfate, barium sulfate, barium titanate and strontium titanate Wherein the wholly aromatic polyamide (a) contains structural units represented by the chemical formulas (I) and (II), and all of the aromatic groups in the structural unit are paraffins. Further, when the molar fractions of the structural units represented by the chemical formulas (I) and (II) in the wholly aromatic polyamide (a) are 1 and m, respectively, the following formulas (4) to (4) to It is more preferable to satisfy (6).

R ¹ : A part or all of hydrogen in the aromatic ring is substituted with a substituent of any of —CF ₃ , —F, —OH, —OCH ₃ , —CH ₃ , —NO ₂ , —CN, and —Br. A para-oriented aromatic group.

R ² : Any para-oriented aromatic group.

R ³ : a para-oriented aromatic group having any one of a group containing S, a group containing P, a group containing Si, a halogenated hydrocarbon group, or a group containing an ether bond. However, in the molecule, structural units having these groups may be mixed.

R ⁴ : Any para-oriented aromatic group.

60 ≦ l <100 (4)
0 <m ≦ 40 (5)
97 ≦ l + m ≦ 100 (6)
In chemical formula (I), R ¹ is preferably a para-oriented aromatic group from the viewpoint of heat resistance. When R ¹ is not a para-oriented aromatic group, the coefficient of thermal expansion increases and the heat resistance may also decrease. In R ¹ , some or all of hydrogens in the aromatic ring are substituted with any of —CF ₃ , —F, —OH, —OCH ₃ , —CH ₃ , —NO ₂ , —CN, and —Br. It is preferable. When there is no substituent, the polymer may be colored yellow, and even when inorganic particles are added, the reflectance may be lowered. Substituents can make the polymer transparent, and the YI value when filmed can be controlled to -5 or more and 5 or less, so that high reflectance and whiteness can be obtained when inorganic particles are added. Group is preferable, and —CF ₃ , —F, —OH, —OCH ₃ , —Cl, —CH ₃ , —NO ₂ , —CN, and —Br groups can be exemplified, and any of them can be suitably used. it can. Among these, a —CF ₃ group is more preferable.

Here, R ¹ is more preferably a structure selected from structures represented by the chemical formula (III), and most preferably a structure represented by the chemical formula (IV).

  Chemical formula (III):

R ⁵ : any substituent selected from —CF ₃ , —F, —OH, —OCH ₃ , —Cl, —CH ₃ , —NO ₂ , —CN, and —Br. When there are a plurality, they may be the same or different.

  Chemical formula (IV):

In the chemical formula (I), R ² is not particularly limited. An arbitrary para-oriented aromatic group is preferable from the viewpoint of high heat resistance and high rigidity. A structure represented by the chemical formula (V) is more preferable. Most preferred is a structure represented by chemical formula (VI).

  Chemical formula (V):

  Chemical formula (VI):

In the chemical formula (II), R ³ is preferably a para-oriented aromatic group from the viewpoint of heat resistance. When R ³ is not a para-oriented aromatic group, the coefficient of thermal expansion is increased and the heat resistance may be lowered. In addition, R ³ can make the polymer transparent and further can control the YI value when filmed to -5 or more and 5 or less, so that when adding inorganic particles, high reflectance and whiteness can be obtained. It is preferable that the molecule contains a group containing S, a group containing P, a group containing Si, a halogenated hydrocarbon group, or a structural unit having an ether bond. These structural units may be mixed. R ³ is preferably any one of the structures represented by the following chemical formula (VII).
Chemical formula (VII):

In the chemical formula (II), R ⁴ is not particularly limited. An arbitrary para-oriented aromatic group is preferable from the viewpoint of high heat resistance and high rigidity. A structure represented by the chemical formula (V) is more preferable. Most preferred is a structure represented by chemical formula (VI).

  Chemical formula (V):

  Chemical formula (VI):

  Examples of the inorganic particles (I) (hereinafter sometimes simply referred to as inorganic particles) contained in the wholly aromatic polyamide film of the present invention include titanium oxide, zirconium oxide, calcium oxide, silicon oxide, zinc oxide, aluminum oxide, and zinc sulfide. It is preferably at least one particle selected from the group consisting of calcium sulfate, barium sulfate, barium titanate and strontium titanate. Among these, it is preferable to use titanium oxide because the reflectance of the obtained film can be increased. There are two types of titanium oxide, anatase type and rutile type, which have different crystal structures, and these may be used in combination. However, it is preferable to use a rutile type having a high refractive index and high photostability. Further, it is preferable to form a coating film on the surface of these inorganic particles because a high reflectance can be maintained even after a high temperature process.

Various treatments are performed on the coating film. When titanium oxide is used, it is particularly preferable to form a coating film on the surface of the inorganic particles with SiO _2, Al ₂ O _3, or ZrO. Furthermore, after forming the coating film with SiO _2, Al ₂ O _3, or ZrO, the polyol treatment and the siloxane treatment are preferably performed because the affinity with the resin is improved and the dispersibility is improved.

  The volume average particle size of the inorganic particles used is preferably 0.01 μm or more and 5 μm or less, more preferably 0.05 μm or more and 1 μm or less, and further preferably 0.1 μm or more and 1 μm or less. When the volume average particle diameter of the inorganic particles is less than 0.01 μm, light from the LED element is transmitted and the reflectance is lowered, so that the light may not be used efficiently. In addition, when the volume average particle size of the inorganic particles exceeds 5 μm, the inorganic particles serve as a base point and the film may be easily broken, and the reflectance of light having a wavelength emitted by the LED element may be lowered. is there. In addition, although the inorganic particles have a spherical shape or a needle shape, a spherical shape is preferable from the viewpoint of improving the reflectance.

  Here, the volume average particle diameter is obtained by observing the appearance of inorganic particles with a scanning electron microscope (SEM) and performing image processing. Specifically, when an SEM photograph obtained by SEM observation (magnification: 5,000 times) is used with an image analyzer (for example, “Luzex IIIU” manufactured by Nireco Co., Ltd.), Take the particle size interval of primary particles on the axis (0.05 μm from 0.1 μm to 0.45 μm), plot the frequency (%) of the number of particles observed on the vertical axis to obtain the distribution curve, From the cumulative distribution curve, the particle size with the highest degree of accumulation can be determined as the volume average particle size. In addition, in the case where the inorganic particles have a fibrous shape such as a needle shape, in the SEM photograph obtained by SEM observation (magnification: 5,000 times), image analysis was performed in the same manner, and the short axis length was Take each length section (0.01μm from 0.01μm to 0.10μm), plot the frequency (%) of the number of particles observed on the vertical axis to obtain the distribution curve, and for the long axis , Taking each length section of long axis length (1 μm from 1 μm to 10 μm), plotting the frequency (%) of the number of particles observed on the vertical axis to obtain a distribution curve, from the cumulative distribution curve, The short axis length and the long axis length with the greatest cumulative degree can be obtained as the volume average particle diameter.

  When inorganic particles are used in obtaining the wholly aromatic polyamide film of the present invention, there are the following three timings for adding inorganic particles.

    A. The wholly aromatic polyamide is polymerized using an organic solvent in which inorganic particles are dispersed.

    B. It is added during the polymerization of wholly aromatic polyamide.

    C. It is added after the polymerization of the wholly aromatic polyamide is completed.

  Among these, addition at the timing of A or C is particularly preferable from the viewpoint of increasing the degree of polymerization and dispersibility. Most preferably, it is added at the timing of C.

  Since the wholly aromatic polyamide of the present invention produces hydrogen chloride during polymerization, a step for neutralizing it is necessary, and the pH changes many times during the production process. For this reason, the added inorganic particles may aggregate due to a change in pH, or may separate from the polymer solution and precipitate. Therefore, when added at the timing of A or B, the dispersibility may deteriorate. Further, at any timing of addition, for the purpose of improving dispersibility, it is preferable to add after adding a slurry form in which inorganic particles are dispersed in an organic solvent at a ratio of 20% by mass or less.

  As inorganic particles used in the wholly aromatic polyamide film of the present invention, it is possible to contain two or more kinds of inorganic particles from the above-mentioned inorganic particles. For example, a film having high reflectivity and excellent heat dissipation can be obtained by using titanium oxide and aluminum oxide in combination.

  The wholly aromatic polyamide film of the present invention comprises 100% by mass of the entire organic solvent solution (U) with respect to the organic solvent solution (U) containing the wholly aromatic polyamide (A) and inorganic particles (I). When the content of the polyamide (a) is a (mass%) and the content of the inorganic particles (ii) is b (mass%), the following expressions (7) and (8) are satisfied, and i) described later To iii).

1 ≦ a <20 (7)
0.3 ≦ b / a <2 (8)
In the above formulas (7) and (8), it is more preferable that the following formulas (9) and (10) are satisfied, respectively.

3 ≦ a <15 (9)
0.5 ≦ b / a <1.5 (10)
More preferably, the following expressions (11) and (12) are satisfied.

3 ≦ a <10 (11)
0.5 ≦ b / a <1 (12)
In the above formula (7), if a is smaller than 1, it may be easily broken when formed into a film. On the other hand, when a is 20 or more, the solution viscosity of the organic solvent solution (u) becomes too high, and the solution may lose fluidity, making it difficult to form a film. In the above formula (8), when the value of b / a is less than 0.3, the reflectance of the obtained film may be lowered. On the other hand, when the value of b / a exceeds 2, the obtained film is fragile and easily broken, and handling may be difficult.

  Since the wholly aromatic polyamide film of the present invention generally has a high melting point and it is difficult to form a film by a melt extrusion method, a solution casting method is used. There are wet film formation methods, dry and wet film formation methods, dry film formation methods, and precipitation film formation methods, among which solution film formation methods include wet film formation methods, dry and wet film formation methods, and precipitation film formation methods. Can be preferably used, but is particularly preferable because a film having a high reflectance can be obtained by forming a film by a wet film forming method or a precipitation film forming method. In general, the wet film forming method generally involves immersing a polymer solution developed or cast on a support plate together with the support plate directly in a wet bath to remove the solvent in the polymer solution. Extremely fast, countless voids are generated on the film surface. For this reason, by producing the wholly aromatic polyamide film of the present invention by a wet film-forming method, it is possible to generate countless voids not only on the surface voids but also at the interface between the polymer and the inorganic particles, and thus highly reflective. Rate film can be obtained. This is presumably because the solidification rate is extremely fast, so that the solidification is completed before the surface of the inorganic particles is completely covered with the polymer. In the deposition film forming method, generally, a polymer solution developed or cast on a support plate is introduced into a temperature-controlled environment together with the support plate, and the polymer solution is absorbed by absorbing the polymer solution, and then the polymer solution is added. Voids can be formed not only on the film surface but also on the inside by removing the polymer solution by removing the polymer solution by immersing it in the wet bath together with the support plate or after peeling from the support plate. For this reason, a highly reflective film can be obtained.

  Conventionally, voids are not generated only by adding inorganic particles to a polymer to form a film, and voids are often not generated unless the film is stretched, but a wet film forming method or a precipitation film forming method is used. If it is applied, it is industrially useful since a void can be formed at the interface between the polymer and the inorganic particles and a film having a high reflectance can be obtained without requiring a stretching step. From the above, the aromatic polyamide film of the present invention is preferably produced by a production method having the following steps i) to iii).

      i) An organic solvent solution (U) is spread on a support plate.

    ii) A liquid (e) containing 30% by mass or more of water is brought into contact with the organic solvent solution (U) on the support plate for 2 minutes or more. Alternatively, after introducing the organic solvent solution (U) on the support plate into a temperature-controlled and humidity-controlled environment having a temperature of 5 ° C. or more and 95 ° C. or less and a relative humidity of 50% or more and 100% or less, water is added. A liquid containing 10% by mass or more is brought into contact for 2 minutes or more.

  iii) Heat at a temperature of 200 ° C. to 500 ° C. for 10 seconds to 10 minutes.

  In general, a resin plate such as a SUS plate, a glass plate, a commercially available polyethylene terephthalate film, a polyimide film, or a polyamide film can be suitably used as the support plate for developing the organic solvent solution (U). Moreover, it is preferable that the process of said (ii) is a process immersed for 2 minutes or more in the tank (o) containing the liquid (e) with the support plate which developed the organic-solvent solution (u). The liquid (e) is generally composed of an aqueous solvent, and is a mixed solvent with an organic solvent such as alcohol, glycol, ketone, amide solvent, N-methyl-2-pyrrolidone in addition to water. There is no problem. The water content is preferably 50% by mass or more, more preferably the water content is 80% by mass or more, and most preferably the liquid (water) is water (water content 100% by mass). Moreover, the number of the tanks (o) containing the liquid (e) can be appropriately set between 1 tank and 10 tanks. Moreover, it is preferable that the capacity | capacitance of each tank shall be 3L or more. Furthermore, it is preferable that the supply speed (discharge speed, replacement speed) of the liquid to each tank is 0.05 L / min or more and 100 L / min or less. Furthermore, it is also possible to appropriately adjust the water content of the liquid between 1 tank and 10 tanks. The amount of liquid (e) contained in the tank (o) is not particularly limited as long as it is 3L or more, but when the amount of liquid (e) is less than 3L, the organic solvent solution developed on the support plate Since the organic solvent in (U) does not remain in the film and the apparent heat-resistant temperature of the film is lowered, the film may be colored in the subsequent heat treatment step and the reflectance may be lowered. In addition, when the supply rate (discharge rate, replacement rate) of the liquid (e) is less than 0.05 L / min, the concentration of the organic solvent in the liquid (e) in the tank (o) increases, and the organic solvent solution is efficiently Since the organic solvent cannot be removed from the film, the organic solvent does not remain in the film, and the film may be colored in the subsequent heat treatment step to lower the reflectance. Further, when the supply rate of the liquid (e) is higher than 100 L / min, the flow and momentum of the water flow become too strong, which may cause wrinkles and tears.

  In the step (ii), before bringing the organic solvent solution (u) developed on the support plate into contact with the liquid (e), introducing the void into the temperature-conditioned environment for 1 minute or more It is preferable from the point of forming. Here, the temperature-controlled environment means that the relative humidity is 50% to 100% and the temperature is 5 ° C. to 95 ° C.

  About the process of said (iii), it is preferable to heat for 10 second or more and 10 minutes or less at the temperature of 200 to 500 degreeC. More preferably, the heating is performed at a temperature of 200 ° C. or higher and 400 ° C. or lower. More preferably, the heating is performed at a temperature of 230 ° C. or higher and 350 ° C. or lower.

  The wholly aromatic polyamide film of the present invention is a method of forming a gas barrier film by sputtering or vapor deposition, a method of forming an easy-adhesion layer or the like by coating, copper foil, glass, silicon, aluminum plate, stainless steel foil, aluminum vapor deposition. A laminated body can be obtained by a method of bonding to a film or the like through an adhesive layer. Furthermore, it can be set as a laminated body through various films, such as a PET film, a PEN film, a polyimide film, a polyamide film, a PPS film, and an adhesive layer other than the above.

  The wholly aromatic polyamide film of the present invention can be a laminate having a laminate structure with an aromatic polyamide film having an average light transmittance of 70% or more in light having a wavelength of 400 nm to 700 nm. In order to obtain the laminated structure, an adhesive layer is formed on the wholly aromatic polyamide film of the present invention, and an aromatic polyamide film having an average light transmittance of 70% or more for light having a wavelength of 400 nm to 700 nm is pasted. And a method of forming a laminated structure using pinol or a feed block when casting from a die to a support plate like co-extrusion.

  The wholly aromatic polyamide film of the present invention can be made into a laminate with a copper-coated polyimide film via an adhesive. In order to obtain the said laminated body, the method of sticking a copper sticking polyimide film, after bonding or coating an adhesive sheet and an adhesive agent on a wholly aromatic polyamide film is mentioned.

  Hereinafter, a wholly aromatic polyamide used in the present invention (hereinafter sometimes simply referred to as an aromatic polyamide), a method for producing the composition, a film forming method, and the like will be described, but the present invention is not limited thereto. .

  Various methods can be used for obtaining the aromatic polyamide. 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 acid dichloride and diamine, it is synthesized in an aprotic organic polar solvent. When acid dichloride and diamine are used as monomers in the polymer solution, hydrogen chloride is by-produced. To neutralize 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 the total diamine to the total acid dichloride is preferably 97 to 100: 100 to 97, and if it is outside this value, it is difficult to obtain a polymer solution suitable for molding. Examples of the aprotic polar solvent used in the production of the aromatic polyamide of the present invention include sulfoxide solvents such as dimethyl sulfoxide and diethyl sulfoxide, and formamide solvents such as N, N-dimethylformamide and N, N-diethylformamide. Solvents, acetamide solvents such as N, N-dimethylacetamide, N, N-diethylacetamide, pyrrolidone solvents such as N-methyl-2-pyrrolidone and N-vinyl-2-pyrrolidone, phenol, o-, m- or Examples thereof include phenol solvents such as p-cresol, xylenol, halogenated phenol, and catechol, hexamethylphosphoramide, and γ-butyrolactone, and these are preferably used alone or as a mixture. Furthermore, aromatic hydrocarbons such as xylene and toluene can be used.

  Examples of the carboxylic acid dichloride include terephthalic acid dichloride, 4,4′-biphenyldicarboxylic acid dichloride, 2 fluoro-terephthalic acid dichloride, 2 chloro-terephthalic acid dichloride, 1,4-cyclohexanecarboxylic acid dichloride, and the like. Most preferably, terephthalic acid dichloride and 4,4′-biphenyldicarboxylic acid dichloride are used.

  Examples of the diamine include 3,3′-diaminodiphenylsulfone, 3,4′-diaminodiphenylsulfone, 4,4′-diaminodiphenylsulfone, bis [4- (3-aminophenoxy) phenyl] sulfone, and bis [4- (4-aminophenoxy) phenyl] sulfone, bis [3- (3-aminophenoxy) phenyl] sulfone, 2,2′-ditrifluoromethyl-4,4′-diaminobiphenyl, 2-chloroparaphenylenediamine, 4, Although 4'-diaminodiphenyl ether is mentioned, 4,4'-diaminodiphenyl sulfone and 2,2'-ditrifluoromethyl-4,4'-diaminobiphenyl are most preferably used.

The aromatic polyamide 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.

  In addition, various end-capping agents can be used for the purpose of preventing coloring and suppressing the formation of a polymer having a very high molecular weight. For example, benzoyl chloride, substituted benzoyl chloride and acetic anhydride are preferable, and benzoyl chloride and substituted benzoyl chloride are more preferable. As the substituent of the substituted benzoyl chloride, fluorine compounds such as fluorine and trifluoromethyl, and bulky hydrocarbon groups such as t-butyl and adamantane are preferable. The addition amount of the terminal blocking agent is preferably 1.0 mol% or less when the total molar fraction of the dicarboxylic acid residue and the diamine residue is 100 mol%. If it exceeds 1.0 mol%, the intrinsic viscosity may not be sufficiently increased, and the resulting film may become brittle.

  Next, a method for adjusting the film forming stock solution will be described.

  The film-forming stock solution used when obtaining the wholly aromatic polyamide film of the present invention can be used as it is as the wholly aromatic polyamide polymer solution obtained by the above polymerization method, but when using inorganic particles, It can be obtained by adding inorganic particles to the wholly aromatic polyamide polymer solution obtained by the polymerization method and kneading the polymer solution. There are the following three timings for adding inorganic particles.

    A. The wholly aromatic polyamide is polymerized using an organic solvent in which inorganic particles are dispersed.

    B. It is added during the polymerization of wholly aromatic polyamide.

    C. It is added after the polymerization of the wholly aromatic polyamide is completed.

  Among these, addition at the timing of A or C is particularly preferable from the viewpoint of dispersibility. Most preferably, it is added at the timing of C.

  Since the wholly aromatic polyamide of the present invention produces hydrogen chloride during polymerization, a step for neutralizing it is necessary, and the pH changes many times during the production process. For this reason, the added inorganic particles may aggregate due to a change in pH, or may separate from the polymer solution and precipitate. Therefore, when added at the timing of A or B, the dispersibility may deteriorate. Further, at any timing of addition, for the purpose of improving dispersibility, it is preferable to add after adding a slurry form in which inorganic particles are dispersed in an organic solvent at a ratio of 20% by mass or less.

  In addition, the wholly aromatic polyamide polymer solution to which inorganic particles have been added contains a large amount of gas such as air or nitrogen, so that when the film is formed, these gases may become bubbles and become a defect. It is preferable to use after removing the gas from the polymer solution by pressurization.

  Next, film formation will be described.

  Since the aromatic polyamide used in the present invention is soluble in an organic solvent, the film-forming stock solution prepared as described above is preferably formed into a film by a so-called solution film-forming method.

  The solution casting method includes a dry and wet film forming method, a dry film forming method, a wet film forming method, and a deposition film forming method, and any film forming method may be used. From the viewpoint of obtaining high reflectivity and high whiteness, film formation by a wet film formation method, a dry wet film formation method or a precipitation film formation method, in which the film formation process is easily controlled, is preferable. Here, the wet film forming method will be described as an example.

  In the case of forming a film by a wet film forming method, the stock solution is extruded from a die and introduced into a wet bath. As a typical example, (1) the film forming stock solution extruded from the die passes through an air layer, and the wet bath (2) A method of casting a film forming stock solution extruded from a die onto a support plate and introducing the whole support plate into a wet bath. It can be selected as appropriate from the type, concentration, viscosity, etc. of the film-forming stock solution. The method of introducing into a wet bath after extending can be preferably used. Examples of the support plate include a drum, an endless belt, a film, and the like. The film is extruded onto any one of the support plates to form a thin film, and then the thin film layer is leveled for about 10 seconds to 20 minutes. Further, a film having a smooth surface can be obtained by making the surfaces of the drum, endless belt and film used in this drying process as smooth as possible. The film after the completion of the process is introduced into the wet bath together with the support plate, desalted, desolvated, etc., and further stretched, dried and heat treated to form a film.

  Stretching is in the range of 0.8 to 8 (drawing ratio is defined by dividing the film area after stretching by the area of the film before stretching. 1 or less means relaxation) as the stretching ratio. Preferably, it is 1.1-8. Moreover, it is preferable to heat-process at the temperature of 200 to 500 degreeC as heat processing. More preferably, the heat treatment is preferably performed at a temperature of 200 ° C. to 400 ° C., more preferably 230 ° C. to 350 ° C. for several seconds to several minutes. Furthermore, it is effective to gradually cool the film after stretching or heat treatment, and it is effective to cool at a rate of 50 ° C./second or less.

  The structure of the wholly aromatic polyamide is determined by the diamine and carboxylic acid dichloride which are the raw materials. When the raw material is unknown, structural analysis is performed from the aromatic polyamide composition. As this method, mass analysis, analysis by nuclear magnetic resonance method, spectroscopic analysis, or the like can be used.

  The film (fully aromatic polyamide film) obtained from the aromatic polyamide of the present invention may be a single layer film or a laminated film.

  The wholly aromatic polyamide film or laminate of the present invention comprises a flexible pudding and circuit board for mounting LED elements, a rigid circuit board for mounting LED elements laminated with a metal layer, and a circuit board cover for LED element mounting. It is suitably used for various applications such as films, flexible printed boards, back sheets for solar cells, semiconductor mounting boards, acoustic diaphragms, multilayer laminated circuit boards and the like.

  The present invention will be described more specifically with reference to the following examples. However, the present invention is not limited to these examples. In addition, the physical property measurement method and the effect evaluation method in the present invention were performed according to the following methods.

(1) Reflectance The reflectance was measured using the following apparatus and the reflectance corresponding to light having a wavelength of 425 nm was determined.

Apparatus: UV measuring instrument U-3410 (manufactured by Hitachi Instruments)
Wavelength range: 300 nm to 800 nm (of which a value of 425 nm is used)
(2) 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 65 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.

Average coefficient of thermal expansion (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.

Load = 44.5 (mN) × d (μm) / 10 (μm)
d (μm): film thickness (3) Flame retardance A sample piece having a length of 200 mm is wound into a cylindrical shape, and attached perpendicularly to a clamp. Next, a test in which a 3 second indirect flame with a 20 mm flame was performed twice was carried out at n = 5, and the flame retardancy was judged from the following criteria based on the combustion behavior. By satisfying all the following criteria defined in UL94, VTM-0 is satisfied.

Judgment criteria (VTM-0)
Burning time of each specimen: 10 seconds or less Total burning time of 5 specimens: 50 seconds or less Combustion of each specimen + glowing time: 30 seconds or less Combustion until clamp: None Cotton ignition by dripping: None (4) Heating Reflectivity after test The method described in (1) Reflectance is the reflectivity in a state where the film is left in an oven at 200 ° C. under substantially no tension for 2 hours and heat-treated in air, and then the film is returned to room temperature. Measured with

(5) Reflectivity after solder reflow The film is allowed to stand in an atmosphere of 23 ° C. and 55% RH for 24 hours and then passed through a 260 ° C. infrared heating furnace for 30 seconds (260 ° C. solder reflow process). After passing this process, the reflectance in the state which returned the film to room temperature was measured by the method as described in (1) reflectance.

(6) Whiteness Whiteness was calculated | required from L value, a value, and b value measured in the reflection mode using the spectrocolorimeter (SE-2000) by Nippon Denshoku Industries Co., Ltd.

Whiteness = 100 − [(100−L value) ² + (a value) ² + (b value) ² ] ^1/2
(7) Total light transmittance Using a haze meter NDH5000 (manufactured by Nippon Denshoku Industries Co., Ltd.), according to JIS-K7136 (2000), the total light transmittance (%) of the film at 23 ° C. is 3 places. The average value was measured.

(8) YI value Using a spectrocolorimeter (SE-2000) manufactured by Nippon Denshoku Industries Co., Ltd., the wholly aromatic polyamide film to which inorganic particles are not added is measured in a transmission mode, and inorganic particles are added. The wholly aromatic polyamide film was measured in the reflection mode to obtain the YI value.

(9) Heat shrinkage rate The film was cut into a strip shape having a width of 10 mm and a length of 150 mm, and a mark was placed at 25 mm from both ends of the film so that the measurement length was 100 mm. as measured by Nikon Corporation of universal projector (V-16A), the dimensions of the time this was the L _0. Further, after the film was heat-treated in air at 200 ° C. for 30 minutes under no tension, the dimensions were similarly measured with a universal projector (V-16A) manufactured by Nikon Corporation. The dimensions of this time as L _1, the heat shrinkage was calculated from the following equation. The average value of the five heat shrinkage rates was used as the value.

Thermal contraction rate (%) = {(L ₁ −L ₀ ) / L ₀ } × 100
L ₀ : dimension in the film forming direction before heat treatment (mm)
L ₁ : Dimensions in the film forming direction after heat treatment (mm)
(10) Film thickness Using a micro thickness gauge (K-402B STAND) manufactured by ANRITSU, the film thickness was measured at five points, and the average value was used as the film thickness.

(11) 260 ° C. solder heat resistance After leaving the film in an atmosphere of 23 ° C. and 55% RH for 24 hours or in a 40 ° C. and 90% RH atmosphere for 96 hours, the film was placed in an infrared heating furnace at 260 ° C. The process of passing for 30 seconds is repeated three times (260 ° C. solder reflow process). After passing through this process, “○” indicates that the film has no deformation or swelling, and “△” indicates that the film is clearly yellow, but there is no deformation or swelling. Things were rated as “x”.

(12) Light transmittance The light transmittance of light having a wavelength of 400 nm to 700 nm was determined by measurement using the following apparatus.

Apparatus: UV measuring instrument U-3410 (manufactured by Hitachi Instruments)
Wavelength range: 300 nm to 800 nm (using an average value of 400 nm to 700 nm)
In addition, the monomer, solvent, and inorganic particle which were used in order to obtain the film in Examples and Comparative Examples are as follows.

Monomer TFMB: 2,2′-ditrifluoromethyl-4,4′-diaminobiphenyl (manufactured by Toray Fine Chemical Co., Ltd.)
4,4′-DDS: 4,4′-diaminodiphenylsulfone (manufactured by Wakayama Seika Co., Ltd.)
3,3′-DDS: 3,3′-diaminodiphenylsulfone (manufactured by Tokyo Chemical Industry Co., Ltd.)
CPA: 2-chloroparaphenylenediamine (manufactured by Nippon Kayaku Co., Ltd.)
DPE: 4,4′-diaminodiphenyl ether (manufactured by Tokyo Chemical Industry Co., Ltd.)
TPC: Terephthalic acid dichloride (Alfa Aesar)
4,4′-BPC: 4,4′-biphenyldicarbonyl chloride (manufactured by Toray Fine Chemical Co., Ltd.)
CTPC: 2-chloroterephthalic acid dichloride (made by Showa Kogyo Co., Ltd.)
Inorganic particles CR-90-2: Titanium oxide (made by Ishihara Sangyo Co., Ltd.)
PF690: Titanium oxide (made by Ishihara Sangyo Co., Ltd.)
FTL-110: Titanium oxide (made by Ishihara Sangyo Co., Ltd.)
(Note that since FTL-110 is acicular titanium oxide, the volume average particle size (3 μm) based on the major axis length and the volume average particle size (0.07 μm) based on the minor axis length are expressed as “3 × 0.07 ”)
High micron HE5: Barium sulfate (manufactured by Takehara Chemical Co., Ltd.)
Solvent NMP: N-methyl-2-pyrrolidone (Mitsubishi Chemical Corporation)
Synthesis example 1:
2.85 g of lithium bromide was placed in a 300 ml three-necked flask equipped with a stirrer, and dried by heating to 110 ° C. using a mantle heater under a nitrogen stream. After cooling to 30 ° C., 9.08 g of TFMB, 0.78 g of 4,4′-DDS, and 159 ml of NMP were added and cooled to 0 ° C. in a nitrogen atmosphere. A mixture of 1.74 g of 4′-BPC was added in 5 portions. After stirring for 1 hour, hydrogen chloride generated by the reaction was neutralized with lithium carbonate to obtain a wholly aromatic polyamide polymer solution.

Synthesis example 2:
4.29 g of lithium chloride was placed in a 300 ml three-necked flask equipped with a stirrer, and dried by heating to 110 ° C. using a mantle heater under a nitrogen stream. After cooling to 30 ° C., 8.15 g of TFMB, 1.58 g of 4,4′-DDS, and 156 ml of NMP were added, cooled to 0 ° C. in a nitrogen atmosphere, and stirred for 4, 4′-BPC1. 75 g was added in 5 portions. Then, after stirring for 30 minutes, 5.12 g of TPC was added in 5 portions over 30 minutes while cooling and stirring. After stirring for 1 hour, hydrogen chloride generated by the reaction was neutralized with lithium carbonate to obtain a wholly aromatic polyamide polymer solution.

Synthesis Example 3:
In a 300 ml three-necked flask equipped with a stirrer, 1.39 g of lithium bromide was placed, heated to 110 ° C. using a mantle heater under a nitrogen stream, and dried. After cooling to 30 ° C., 3.07 g of TFMB, 1.59 g of 4,4′-DDS, and 93 ml of NMP were added, cooled to 0 ° C. in a nitrogen atmosphere, and 2.57 g of TPC over 30 minutes with stirring. And a mixture of 0.88 g of 4,4′-BPC was added in 5 portions. After stirring for 1 hour, hydrogen chloride generated by the reaction was neutralized with lithium carbonate to obtain a wholly aromatic polyamide polymer solution.

Synthesis Example 4:
In a 300 ml three-necked flask equipped with a stirrer, 1.39 g of lithium bromide was placed, heated to 110 ° C. using a mantle heater under a nitrogen stream, and dried. After cooling to 30 ° C, TFMB (3.07g), 4,4'-DDS (1.59g) and NMP (93ml) were added, and CR-90-2 (3.48g) was dried overnight in an 80 ° C oven. Under a nitrogen atmosphere, a mixture of 2.57 g of TPC and 0.88 g of 4,4′-BPC was added in 5 portions over 30 minutes while cooling to 0 ° C. and stirring. After stirring for 1 hour, hydrogen chloride generated by the reaction was neutralized with lithium carbonate to obtain a white wholly aromatic polyamide polymer solution. When the obtained polymer solution was stored for 30 days and observed again, the added inorganic particles were precipitated at the bottom of the polymer solution and the polymer solution and the inorganic particles were separated.

Synthesis Example 5:
In a 300 ml three-necked flask equipped with a stirrer, under a nitrogen stream, 7.42 g of CPA, 2.60 g of DPE, and 136 ml of NMP were placed, cooled to 0 ° C. in a nitrogen atmosphere, and stirred for 30 minutes with stirring. 2 g was added dropwise. After stirring for 1 hour, hydrogen chloride generated by the reaction was neutralized with lithium carbonate to obtain a wholly aromatic polyamide polymer solution.

Synthesis Example 6:
In a 300 ml three-necked flask equipped with a stirrer, put 8.19 g of 4,4′-DDS, 8.19 g of 3,3′-DDS, 141 ml of NMP and cool to 0 ° C. under a nitrogen atmosphere. While stirring, 13.40 g of TPC was added over 30 minutes. After stirring for 1 hour, hydrogen chloride generated by the reaction was neutralized with lithium carbonate to obtain a wholly aromatic polyamide polymer solution.

Reference example 1:
A part of the polymer solution obtained in Synthesis Example 1 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 1 minute to obtain a colorless and transparent wholly aromatic polyamide film having a thickness of 8 μm (dry and wet) Formula film formation). The average light transmittance in the light with a wavelength of 400 nm-700 nm in the obtained film was 85.5% .

Reference example 2:
A part of the polymer solution obtained in Synthesis Example 2 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 1 minute to obtain a 10 μm thick colorless and transparent wholly aromatic polyamide film (dry and wet) Formula film formation). The average light transmittance in light with a wavelength of 400 nm to 700 nm in the obtained film was 87.3% .

Reference Example 3:
A part of the polymer solution obtained in Synthesis Example 3 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 1 minute to obtain a colorless and transparent wholly aromatic polyamide film having a thickness of 8 μm (dry and wet) Formula film formation). The average light transmittance in the light with a wavelength of 400 nm-700 nm in the obtained film was 86.1% .

Reference example 4:
A part of the polymer solution obtained in Synthesis Example 5 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 and fixed to a metal frame, and this was immersed in a 5 L water bath (water content 100 wt%) supplying water at 0.5 L / min for 10 minutes. Further, heat treatment was performed at 280 ° C. for 1 minute to obtain a wholly aromatic polyamide film having a thickness of 4.4 μm (dry and wet film formation). The average light transmittance in the light with a wavelength of 400 nm-700 nm in the obtained film was 77.3% .

Reference example 5:
A part of the polymer solution obtained in Synthesis Example 6 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 1 minute to obtain a 10 μm thick colorless and transparent wholly aromatic polyamide film (dry and wet) Formula film formation). The average light transmittance in the light with a wavelength of 400 nm-700 nm in the obtained film was 85.8% .

Example 1
In a 300 ml three-necked flask equipped with a stirrer, 3.5 g of CR-90-2 was weighed as inorganic particles, and 27.3 g of NMP was added thereto and stirred for 5 minutes to obtain a slurry of CR-90-2 and NMP. . 100 g of the wholly aromatic polyamide polymer solution obtained by the method described in Synthesis Example 1 was added thereto, and further stirred for 3 hours to obtain a white wholly aromatic polyamide polymer solution to which inorganic particles were added.

  A part of the obtained polymer solution was taken on a PET film (T60 thickness 100 μm, manufactured by Toray Industries, Inc.), and a uniform film was formed using a bar coater. This was immersed for 30 minutes in a 5 L water bath (water content 100 wt%) supplying water at 0.5 L / min together with the PET film to obtain a self-supporting film. Subsequently, the obtained film was peeled off from the PET film, fixed to a metal frame, and subjected to heat treatment at 280 ° C. for 1 minute to obtain a white wholly aromatic polyamide film (wet film formation). The physical properties of the obtained film were measured and are shown in Table 4.

  In addition, the diamine amount (mol%) shown in Tables 1 to 3 was expressed as a component amount when the total amount of diamine components contained in the polymer was 50 mol%. Moreover, about the amount of acid dichloride (mol%), it represented with the component amount when the diamine total amount shall be 50 mol%.

(Example 2)
A white wholly aromatic polyamide film obtained by the method described in Example 1 and a wholly aromatic polyamide film obtained by the method described in Reference Example 1 were adhesive materials (SK-1478 manufactured by Soken Kagaku Co., Ltd., thickness 18 μm). The sample pasted through was made. The physical properties of the laminated film after pasting were measured and are shown in Table 4. The reflectance, whiteness, YI value, and total light transmittance were measured from the white wholly aromatic polyamide film side.

(Examples 3 to 7)
The amount of inorganic particles added to the white wholly aromatic polyamide polymer solution obtained by the method of Example 1, the kind of inorganic particles, the film thickness, etc. were changed as shown in Table 4, and the wholly aromatic polyamide film was The physical properties of the film thus prepared and measured were shown in Table 4.

(Example 8)
In a 300 ml three-necked flask equipped with a stirrer, 3.5 g of PF690 was weighed as inorganic particles, 27.3 g of NMP was added thereto, and stirred for 5 minutes to obtain a slurry of CR-90-2 and NMP. 100 g of the wholly aromatic polyamide polymer solution obtained by the method described in Synthesis Example 2 was added thereto, and further stirred for 3 hours to obtain a white wholly aromatic polyamide polymer solution to which inorganic particles were added.

  A part of the obtained polymer solution was taken on a PET film (T60 thickness 100 μm, manufactured by Toray Industries, Inc.), and a uniform film was formed using a bar coater. This was immersed for 30 minutes in a 5 L water bath (water content 100 wt%) supplying water at 0.5 L / min together with the PET film to obtain a self-supporting film. Subsequently, the obtained film was peeled off from the PET film, fixed to a metal frame, and subjected to heat treatment at 280 ° C. for 1 minute to obtain a white wholly aromatic polyamide film (wet film formation). The physical properties of the obtained film were measured and are shown in Table 4.

(Examples 9 and 10)
For the white wholly aromatic polyamide polymer solution obtained by the method of Example 1, the kind of inorganic particles to be added, the film thickness, etc. were changed as shown in Tables 4 and 5 to prepare wholly aromatic polyamide films. The physical properties of the obtained film were measured and are shown in Table 4 and Table 5.

(Example 11)
A part of the polymer solution obtained by the method described in Synthesis Example 4 was taken on a PET film (T60 thickness 100 μm, manufactured by Toray Industries, Inc.), and a uniform film was formed using a bar coater. This was immersed for 30 minutes in a 5 L water bath (water content 100 wt%) supplying water at 0.5 L / min together with the PET film to obtain a self-supporting film. Subsequently, the obtained film was peeled off from the PET film, fixed to a metal frame, and heat-treated at 280 ° C. for 1 minute to obtain a wholly aromatic polyamide film (wet film formation). The physical properties of the obtained film were measured and are shown in Table 5.

(Example 12)
In a 300 ml three-necked flask equipped with a stirrer, 3.5 g of CR90-2 was weighed, and 27.3 g of N-methyl-2-pyrrolidone was added thereto and stirred for 5 minutes to obtain a slurry of inorganic particles and NMP. Thereto was added 100 g of a wholly aromatic polyamide polymer solution obtained by the method described in Synthesis Example 1, and the mixture was further stirred for 3 hours to obtain a white wholly aromatic polyamide polymer solution to which inorganic particles were added.

  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 and fixed to a metal frame, and this was immersed in a 5 L water bath (water content 100 wt%) supplying water at 0.5 L / min for 10 minutes. Furthermore, heat treatment was performed at 280 ° C. for 1 minute to obtain a wholly aromatic polyamide film (dry and wet film formation). The physical properties of the obtained film were measured and are shown in Table 5.

(Example 13)
In a 300 ml three-necked flask equipped with a stirrer, 3.5 g of CR-90-2 was weighed as inorganic particles, and 27.3 g of NMP was added thereto and stirred for 2 hours to obtain a slurry of CR-90-2 and NMP. . 100 g of the wholly aromatic polyamide polymer solution obtained by the method described in Synthesis Example 2 was added thereto, and further stirred for 3 hours to obtain a white wholly aromatic polyamide polymer solution to which inorganic particles were added.

  A part of the obtained polymer solution was taken on a PET film (T60 thickness 100 μm, manufactured by Toray Industries, Inc.), and a uniform film was formed using a bar coater. This was introduced into a constant temperature and humidity chamber whose temperature was controlled at 5 ° C. and 80% together with the PET film and allowed to stand for 15 minutes. Thereafter, the film was immersed for 30 minutes in a 5 L water bath (water content 100 wt%) supplying water at 0.5 L / min together with the PET film to obtain a self-supporting film. Subsequently, the obtained film was peeled off from the PET film, fixed to a metal frame, and heat-treated at 280 ° C. for 1 minute to obtain a white wholly aromatic polyamide film (precipitation film forming method). The physical properties of the obtained film were measured and are shown in Table 5.

(Examples 14 and 15)
About the white wholly aromatic polyamide polymer solution obtained by the method of Example 13, the temperature and humidity control conditions were changed as shown in Table 5 to prepare a wholly aromatic polyamide film, and the physical properties of the obtained film were Measured and shown in Table 5.

(Example 16)
In a 300 ml three-necked flask equipped with a stirrer, 3.5 g of Hi-micron HE5 was weighed, and 27.3 g of N-methyl-2-pyrrolidone was added thereto and stirred for 2 hours to obtain a slurry of inorganic particles and NMP. Thereto was added 100 g of a wholly aromatic polyamide polymer solution obtained by the method described in Synthesis Example 2, and the mixture was further stirred for 3 hours to obtain a white wholly aromatic polyamide polymer solution to which inorganic particles were added.

  A part of the obtained polymer solution was taken on a PET film (T60 thickness 100 μm, manufactured by Toray Industries, Inc.), and a uniform film was formed using a bar coater. This was immersed for 30 minutes in a 5 L water bath (water content 100 wt%) supplying water at 0.5 L / min together with the PET film to obtain a self-supporting film. Subsequently, the obtained film was peeled off from the PET film, fixed to a metal frame, and heat-treated at 280 ° C. for 1 minute to obtain a wholly aromatic polyamide film (wet film formation). The physical properties of the obtained film were measured and are shown in Table 5.

(Example 17)
A part of the polymer solution obtained by the method described in Example 16 was taken on a PET film (T60 thickness 100 μm, manufactured by Toray Industries, Inc.), and a uniform film was formed using a bar coater. This was introduced into a constant temperature and humidity chamber whose temperature was controlled at 5 ° C. and 80% together with the PET film and allowed to stand for 30 minutes. Thereafter, the film was immersed for 30 minutes in a 5 L water bath (water content 100 wt%) supplying water at 0.5 L / min together with the PET film to obtain a self-supporting film. Subsequently, the obtained film was peeled off from the PET film, fixed to a metal frame, and heat-treated at 280 ° C. for 1 minute to obtain a white wholly aromatic polyamide film (precipitation film forming method). The physical properties of the obtained film were measured and are shown in Table 5.

( Reference Example 18)
In a 300 ml three-necked flask equipped with a stirrer, 3.5 g of CR-90-2 was weighed as inorganic particles, and 27.3 g of NMP was added thereto and stirred for 2 hours to obtain a slurry of CR-90-2 and NMP. . 100 g of the wholly aromatic polyamide polymer solution obtained by the method described in Synthesis Example 6 was added thereto, and the mixture was further stirred for 3 hours to obtain a white wholly aromatic polyamide polymer solution to which inorganic particles were added.

  A part of the obtained polymer solution was taken on a PET film (T60 thickness 100 μm, manufactured by Toray Industries, Inc.), and a uniform film was formed using a bar coater. This was introduced into a constant temperature and humidity chamber whose temperature was controlled at 5 ° C. and 80% together with the PET film and allowed to stand for 15 minutes. Thereafter, the film was immersed for 30 minutes in a 5 L water bath (water content 100 wt%) supplying water at 0.5 L / min together with the PET film to obtain a self-supporting film. Subsequently, the obtained film was peeled off from the PET film, fixed to a metal frame, and heat-treated at 280 ° C. for 1 minute to obtain a white wholly aromatic polyamide film (precipitation film forming method). The physical properties of the obtained film were measured and are shown in Table 5.

(Comparative Example 1)
In a 300 ml three-necked flask equipped with a stirrer, 3.5 g of FTL-110 was weighed, and 20 g of N-methyl-2-pyrrolidone was added thereto and stirred for 5 minutes to prepare a slurry of titanium oxide and N-methyl-2-pyrrolidone. Obtained. 100 g of the wholly aromatic polyamide polymer solution obtained by the method described in Synthesis Example 5 was added thereto, and the mixture was further stirred for 3 hours to obtain a wholly aromatic polyamide polymer solution to which inorganic particles were added.

  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 and fixed to a metal frame, and this was immersed in a 5 L water bath (water content 100 wt%) supplying water at 0.5 L / min for 10 minutes. Further, heat treatment was performed at 280 ° C. for 1 minute to obtain a milky white wholly aromatic polyamide film (dry and wet film formation). The physical properties of the obtained film were measured and are shown in Table 6.

(Comparative Example 2)
In a 300 ml three-necked flask equipped with a stirrer, 1.4 g of FTL-110 was weighed, and 27.3 g of NMP was added thereto and stirred for 5 minutes to obtain a slurry. Thereto was added 100 g of a wholly aromatic polyamide polymer solution obtained by the method described in Synthesis Example 1, and the mixture was further stirred for 3 hours to obtain a wholly aromatic polyamide polymer solution to which inorganic particles were added.

  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 and fixed to a metal frame, and this was immersed in a 5 L water bath (water content 100 wt%) supplying water at 0.5 L / min for 10 minutes. Furthermore, heat treatment was performed at 280 ° C. for 1 minute to obtain a white wholly aromatic polyamide film (dry and wet film formation). The physical properties of the obtained film were measured and are shown in Table 6.

(Comparative Example 3)
In a 300 ml three-necked flask equipped with a stirrer, 3.5 g of CR90-2 was weighed, and 27.3 g of N-methyl-2-pyrrolidone was added thereto, followed by stirring for 5 minutes to obtain a slurry. Thereto was added 100 g of a wholly aromatic polyamide polymer solution obtained by the method described in Synthesis Example 1, and the mixture was further stirred for 3 hours to obtain a white wholly aromatic polyamide polymer solution to which inorganic particles were added.

  A part of the obtained polymer solution was taken on a PET film (T60 thickness 100 μm, manufactured by Toray Industries, Inc.), and a uniform film was formed using a bar coater. This was immersed for 1 minute in a 2 L water bath (water content: 20 wt%) filled with a mixed solvent of water and NMP. Next, when the obtained film was peeled off from the PET film, the film on the PET was not self-supporting, and the film could not be obtained.

(Comparative Example 4)
A part of the polymer solution obtained by the method described in Synthesis Example 2 was taken on a PET film (T60 thickness 100 μm, manufactured by Toray Industries, Inc.), and a uniform film was formed using a bar coater. This was introduced into a constant temperature and humidity chamber whose temperature was controlled at 5 ° C. and 80% together with the PET film and allowed to stand for 15 minutes. Thereafter, the film was immersed for 30 minutes in a 5 L water bath (water content 100 wt%) supplying water at 0.5 L / min together with the PET film to obtain a self-supporting film. Subsequently, the obtained film was peeled off from the PET film, fixed to a metal frame, and heat-treated at 280 ° C. for 1 minute to obtain a white wholly aromatic polyamide film (precipitation film forming method). The physical properties of the obtained film were measured and are shown in Table 6.

Claims (13)

Ri der reflectance of light of 70% or more of the wavelength 425 nm, wholly aromatic polyamide film average thermal expansion coefficient of 200 ° C. from 100 ° C. is Ru Der -10 ppm / ° C. or higher 20 ppm / ° C. or less.   The wholly aromatic polyamide film according to claim 1, which satisfies VTM-0 defined in UL94. The wholly aromatic polyamide film according to claim 1 or 2 , which does not contain a flame retardant. The wholly aromatic polyamide film according to any one of claims 1 to 3 , wherein a decrease in reflectance of light having a wavelength of 425 nm after heating at 200 ° C for 2 hours is 2.0% or less. The wholly aromatic polyamide film according to any one of claims 1 to 4 , having a thickness of 1 to 50 µm. When the molar fractions of the structural units represented by the chemical formulas (I) and (II) are 1 and m, respectively, a wholly aromatic polyamide satisfying the following formulas (1) to (3) and inorganic particles are included. The wholly aromatic polyamide film according to any one of claims 1 to 5 .

R ¹ : A part or all of hydrogen in the aromatic ring is substituted with a substituent of any of —CF ₃ , —F, —OH, —OCH ₃ , —CH ₃ , —NO ₂ , —CN, and —Br. A para-oriented aromatic group.
R ² : Any para-oriented aromatic group.
R ³ : a para-oriented aromatic group having any one of a group containing S, a group containing P, a group containing Si, a halogenated hydrocarbon group, or a group containing an ether bond. However, in the molecule, structural units having these groups may be mixed.
R ⁴ : Any para-oriented aromatic group.
0 ≦ l ≦ 100 (1)
0 ≦ m ≦ 100 (2)
97 ≦ l + m ≦ 100 (3) At least selected from the group consisting of wholly aromatic polyamide (a) and titanium oxide, zirconium oxide, calcium oxide, silicon oxide, zinc oxide, aluminum oxide, zinc sulfide, calcium sulfate, barium sulfate, barium titanate and strontium titanate The wholly aromatic polyamide film according to any one of claims 1 to 6 , comprising one kind of inorganic particles (i), wherein the wholly aromatic polyamide (A) is represented by the chemical formulas (I) and (II). And the aromatic groups of the structural unit are all bonded at the para position, and the moles of the structural unit represented by the chemical formulas (I) and (II) in the wholly aromatic polyamide (a). A wholly aromatic polyamide film satisfying the following formulas (4) to (6) when the fractions are 1 and m, respectively.

R ¹ : A part or all of hydrogen in the aromatic ring is substituted with a substituent of any of —CF ₃ , —F, —OH, —OCH ₃ , —CH ₃ , —NO ₂ , —CN, and —Br. A para-oriented aromatic group.
R ² : Any para-oriented aromatic group.
R ³ : a para-oriented aromatic group having any one of a group containing S, a group containing P, a group containing Si, a halogenated hydrocarbon group, or a group containing an ether bond. However, in the molecule, structural units having these groups may be mixed.
R ⁴ : Any para-oriented aromatic group.
60 ≦ l <100 (4)
0 <m ≦ 40 (5)
97 ≦ l + m ≦ 100 (6) For the organic solvent solution (U) containing the wholly aromatic polyamide (A) and the inorganic particles (I), the total amount of the organic solvent solution (U) is 100% by mass, and the total aromatic polyamide (A) content is a ( Mass%), when the content of the inorganic particles (ii) is b (mass%), the following formulas (7) and (8) are satisfied, and the following steps i) to iii) are included: method for producing a wholly aromatic polyamide film according to any one of 1-7.
1 ≦ a <20 (7)
0.3 <b / a ≦ 2 (8)
i) An organic solvent solution (U) is spread on a support plate.
ii) A liquid (e) containing 10% by mass or more of water is brought into contact with the organic solvent solution (U) on the support plate for 2 minutes or more.
iii) Heat at a temperature of 200 ° C. to 500 ° C. for 10 seconds to 10 minutes. For the organic solvent solution (U) containing the wholly aromatic polyamide (A) and the inorganic particles (I), the total amount of the organic solvent solution (U) is 100% by mass, and the total aromatic polyamide (A) content is a ( Mass%), when the content of the inorganic particles (ii) is b (mass%), the following formulas (7) and (8) are satisfied, and the following steps i) to iii) are included: method for producing a wholly aromatic polyamide film according to any one of 1-7.
1 ≦ a <20 (7)
0.3 <b / a ≦ 2 (8)
i) An organic solvent solution (U) is spread on a support plate.
ii) After introducing the organic solvent solution (U) on the support plate for 1 minute or more in a temperature-controlled environment with a temperature of 5 ° C. or more and 95 ° C. or less and a relative humidity of 50% or more and 100% or less, A liquid containing 10% by mass or more is brought into contact for 2 minutes or more.
iii) Heat at a temperature of 200 ° C. to 500 ° C. for 10 seconds to 10 minutes. A wholly aromatic polyamide in which an organic solvent solution in which a wholly aromatic polyamide is dissolved in an organic solvent in a proportion of 20% by mass or less and a slurry solution in which inorganic particles are dispersed in the organic solvent solution in a proportion of 20% by mass or less are mixed. A method for producing a wholly aromatic polyamide film according to claim 8 or 9 , wherein an organic solvent solution of the inorganic particles is used. Laminate having at least one layer of wholly aromatic polyamide film according to any one of claims 1-7. A laminate having a laminate structure of the wholly aromatic polyamide film according to any one of claims 1 to 7 and an aromatic polyamide film having a light transmittance of 70% or more in light having a wavelength of 400 nm to 700 nm. Wholly aromatic polyamide and Doha polyimide film and laminate was bonded via the adhesive of any of claims 1-7.