JP2017133027A - Polyimide, method for producing polyimide, polyimide solution and polyimide film - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a polyimide that makes it possible to improve hardness while having sufficiently high levels of heat resistance and transparency.SOLUTION: A polyimide comprises two or more repeating units each represented by a polyimide coupled with a group represented by formula (I-1) and a C6-C40 arylene group. The C6-C40 arylene group is 2,2'-dimethyl-4,4'-biphenyl. (R-Rindependently represent H, a C1-10 alkyl or F; n is an integer of 0-12).SELECTED DRAWING: None

Description

  The present invention relates to polyimide, a method for producing polyimide, a polyimide solution, and a polyimide film.

  In recent years, polyimide has attracted attention as a light and flexible material having high heat resistance. As such polyimide, for example, aromatic polyimide (for example, trade name “Kapton” manufactured by DuPont) is widely known. However, although such aromatic polyimide is a polyimide having sufficient flexibility and high heat resistance, it exhibits a brown color and can be used for glass replacement applications and optical applications that require light transmission. It wasn't. Therefore, in recent years, development of an alicyclic polyimide having sufficient light transmittance that can be used for glass substitute applications and the like has been advanced.

  As such alicyclic polyimide, for example, International Publication No. 2011/099518 (Patent Document 1) discloses a polyimide having a repeating unit described by a specific general formula. In addition, such a polyimide as described in Patent Document 1 has sufficient light transmittance and high heat resistance.

International Publication No. 2011/099518

  However, the alicyclic polyimide described in Patent Document 1 is not always sufficient in terms of further improving the hardness.

  This invention is made | formed in view of the subject which the said prior art has, The polyimide which makes it possible to improve hardness more, having sufficiently high heat resistance and transparency, and the polyimide It aims at providing the manufacturing method of the polyimide which can be manufactured efficiently and reliably. Furthermore, another object of the present invention is to provide a polyimide solution and a polyimide film obtained using the polyimide.

As a result of intensive studies to achieve the above object, the inventors of the present invention contain two or more types of repeating units represented by the following general formula (1), and the two or more types of repeating units. By making at least one of the units a repeating unit (A) in which R ¹⁰ in formula (1) is a group represented by the following general formula (2), sufficiently high heat resistance and transparency The present inventors have found that it is possible to further improve the hardness while having the above, and have completed the present invention.

  That is, the polyimide of the present invention has the following general formula (1):

[In the formula (1), X represents the following general formula (I-1):

(In Formula (I-1), R ¹ , R ² , and R ³ each independently represent one selected from the group consisting of a hydrogen atom, an alkyl group having 1 to 10 carbon atoms, and a fluorine atom, and n Represents an integer of 0 to 12.)
And a group represented by the following general formula (I-2):

(In formula (I-2), A is 1 selected from the group consisting of a divalent aromatic group which may have a substituent and has 6 to 30 carbon atoms to form an aromatic ring. And R ⁵ is independently selected from the group consisting of a hydrogen atom and an alkyl group having 1 to 10 carbon atoms.)
Any one group selected from the group consisting of groups represented by:
R ¹⁰ represents an arylene group having 6 to 40 carbon atoms. ]
Containing two or more types of repeating units represented by:
In at least one of the two or more repeating units, R ¹⁰ in the formula (1) is represented by the following general formula (2):

It is a repeating unit (A) which is group represented by these.

The method for producing the polyimide of the present invention includes:
In the presence of a polymerization solvent,
The following general formula (5A):

[In Formula (5A), R ¹ , R ² , and R ³ each independently represent one selected from the group consisting of a hydrogen atom, an alkyl group having 1 to 10 carbon atoms, and a fluorine atom, and n is 0. An integer of ~ 12 is shown. ]
And a compound represented by the following general formula (5B):

[In the formula (5B), A represents a kind selected from the group consisting of a divalent aromatic group which may have a substituent and has 6 to 30 carbon atoms to form an aromatic ring. And R ⁵ is independently selected from the group consisting of a hydrogen atom and an alkyl group having 1 to 10 carbon atoms. ]
At least one tetracarboxylic dianhydride selected from the compounds represented by:
The following general formula (6):
_{^{H 2 N-R 10 -NH 2}} (6)
[In formula (6), R ¹⁰ represents an arylene group having 6 to 40 carbon atoms. ]
And at least one of the aromatic diamines contains the following general formula (7):

A mixture of aromatic diamines that are 4,4′-diamino-2,2′-dimethylbiphenyl represented by:
By reacting
Two or more types of repeating units represented by the general formula (1) are contained, and at least one of the two or more types of repeating units is such that R ¹⁰ in the formula (1) is the general formula (2). It is a method characterized by obtaining the polyimide which is a repeating unit (A) which is a group represented by.

  The polyimide solution of the present invention contains the polyimide of the present invention and an organic solvent.

  Furthermore, the polyimide film of the present invention is a film made of the polyimide of the present invention.

  According to the present invention, polyimide having a sufficiently high heat resistance and transparency and capable of further improving the hardness, and a polyimide capable of efficiently and reliably producing the polyimide. A manufacturing method can be provided. Furthermore, according to this invention, it becomes possible to provide the polyimide solution and polyimide film which are obtained using the said polyimide.

  Hereinafter, the present invention will be described in detail with reference to preferred embodiments thereof.

[Polyimide of the present invention]
Polyimides of the present invention, the repeating unit represented by the general formula (1) contains two or more, and at least one of the two or more repeating units, R ¹⁰ in the formula (1) Is a repeating unit (A) which is a group represented by the general formula (2).

Regarding the group represented by the general formula (I-1) that can be selected as X in the general formula (1), select as R ¹ , R ² , R ^{3 in the} general formula (I-1). The alkyl group that can be used is an alkyl group having 1 to 10 carbon atoms. When the number of carbon atoms exceeds 10, the glass transition temperature is lowered and a sufficiently high heat resistance cannot be achieved. Moreover, as carbon number of the alkyl group which can be selected as such R < ¹ >, R < ² >, R < ³ >, it is preferable that it is 1-6 from a viewpoint that refinement | purification becomes easier, and it is 1-5. Is more preferable, it is still more preferable that it is 1-4, and it is especially preferable that it is 1-3. Further, such an alkyl group that can be selected as R ¹ , R ² , or R ³ may be linear or branched. Further, such an alkyl group is more preferably a methyl group or an ethyl group from the viewpoint of ease of purification.

  Moreover, n in the said general formula (I-1) shows the integer of 0-12. When such a value of n exceeds the upper limit, purification becomes difficult. In addition, the upper limit value of the numerical value range of n in the general formula (I-1) is more preferably 5 and particularly preferably 3 from the viewpoint of easier purification. In addition, the lower limit of the numerical range of n in the general formula (I-1) is the viewpoint of the stability of the raw material compound used when forming the repeating unit represented by the general formula (1), that is, From the viewpoint of more easily producing polyimide, 1 is more preferable, and 2 is particularly preferable. Thus, as n in general formula (I-1), it is especially preferable that it is an integer of 2-3.

  Moreover, regarding the group represented by the general formula (I-2) that can be selected as X in the general formula (1), A in the general formula (I-2) has a substituent. The number of carbons forming an aromatic ring contained in the aromatic group (herein, “the number of carbons forming an aromatic ring” refers to the aromatic group) Is a carbon-containing substituent (such as a hydrocarbon group), it does not include the number of carbons in the substituent, but only the number of carbons in the aromatic ring in the aromatic group. In the case of -ethyl-1,4-phenylene group, the number of carbons forming the aromatic ring is 6.) is 6-30. Thus, A in the general formula (I-2) may have a substituent and is a divalent group having a C 6-30 aromatic ring (a divalent aromatic group). ). When the number of carbons forming such an aromatic ring exceeds the upper limit, the resulting polyimide tends to be colored. Moreover, from the viewpoint of transparency and ease of purification, the number of carbons forming the aromatic ring of the divalent aromatic group is more preferably 6-18, and further preferably 6-12. preferable.

  Such a divalent aromatic group is not particularly limited as long as it satisfies the above condition of the number of carbons. For example, benzene, naphthalene, terphenyl, anthracene, phenanthrene, triphenylene, pyrene, Residues from which two hydrogen atoms are eliminated from an aromatic compound such as chrysene, biphenyl, terphenyl, quaterphenyl, kinkphenyl, etc. Although not particularly limited, for example, 1,4-phenylene group, 2,6-naphthylene group, 2,7-naphthylene group, 4,4′-biphenylene group, 9,10-anthracenylene group and the like can be mentioned. Groups in which at least one hydrogen atom in the residue is substituted with a substituent (for example, 2,5-dimethyl-1,4-phenylene group, 2,3,5, - can be appropriately used tetramethyl-1,4-phenylene group). In such a residue, as described above, the position of the leaving hydrogen atom is not particularly limited. For example, when the residue is a phenylene group, any of the ortho, meta, and para positions is used. It may be the position.

  As such a divalent aromatic group, from the viewpoint that heat resistance is more excellent, a phenylene group which may have a substituent, a biphenylene group which may have a substituent, A naphthylene group which may have a substituent, an anthracenylene group which may have a substituent, and a terphenylene group which may have a substituent are preferable, and each may have a substituent. A phenylene group, a biphenylene group, a naphthylene group, and a terphenylene group are more preferable, and a phenylene group, a biphenylene group, and a naphthylene group, each of which may have a substituent, are further preferable.

  In A in general formula (I-2), the substituent that the divalent aromatic group may have is not particularly limited, and examples thereof include an alkyl group, an alkoxy group, and a halogen atom. Can be mentioned. Among the substituents that such a divalent aromatic group may have, the solubility of polyimide in a solvent is improved, and from the viewpoint of obtaining higher processability, the number of carbon atoms is 1. 10 to 10 alkyl groups and C 1-10 alkoxy groups are more preferred. When the number of carbon atoms of the alkyl group and alkoxy group suitable as such a substituent exceeds 10, the heat resistance of the polyimide tends to decrease. In addition, the number of carbon atoms of an alkyl group and an alkoxy group suitable as such a substituent is preferably 1 to 6 from the viewpoint of obtaining higher heat resistance when a polyimide is produced. 5 is more preferable, 1 to 4 is further preferable, and 1 to 3 is particularly preferable. Moreover, the alkyl group and alkoxy group which can be selected as such a substituent may be linear or branched, respectively.

In addition, the alkyl group that can be selected as R ⁵ in the general formula (I-2) is an alkyl group having 1 to 10 carbon atoms. When such a carbon number exceeds 10, when it uses as a monomer of a polyimide, the heat resistance of the polyimide obtained will fall. Moreover, as carbon number of the alkyl group which can be selected as such R < ⁵ >, it is preferable that it is 1-6 from a viewpoint that a high heat resistance is acquired when a polyimide is manufactured, and it is 1-5. Is more preferable, it is still more preferable that it is 1-4, and it is especially preferable that it is 1-3. Such an alkyl group that can be selected as R ⁵ may be linear or branched.

As the plurality of R ⁵ in the general formula (I-2), higher heat resistance can be obtained when the polyimide is produced, raw materials are easily obtained, purification is easier, etc. From these viewpoints, it is more preferably each independently a hydrogen atom, a methyl group, an ethyl group, an n-propyl group, or an isopropyl group, and particularly preferably a hydrogen atom or a methyl group. In addition, a plurality of R ⁵ in such a formula may be the same or different from each other, but may be the same from the viewpoint of ease of purification and the like. preferable.

  In addition, when X is group represented by the said general formula (I-1), the repeating unit represented by the said general formula (1) is the following general formula (1A):

^{(R 1, R 2, R} 3 and n in formula (1A) have the same meanings as those independently general formula (I-1) ^{in, R 10} is ^{R 10} as defined in the general formula (1) .)
It becomes a repeating unit represented by. In the present invention, from the viewpoint of obtaining higher heat resistance, the repeating unit represented by the general formula (1) is more preferably a repeating unit represented by the general formula (1A).

The arylene group that can be selected as R ¹⁰ in the general formula (1) is an arylene group having 6 to 40 carbon atoms. Such an arylene group preferably has 6 to 30 carbon atoms, more preferably 12 to 20 carbon atoms. If the number of carbon atoms is less than the lower limit, the heat resistance of the polyimide tends to decrease. On the other hand, if the upper limit is exceeded, the solubility of the obtained polyimide in the solvent decreases, and the moldability to a film or the like is reduced. It tends to decrease.

Examples of the arylene group that can be selected as R ¹⁰ in the general formula (1) include the following general formulas (3) to (4) and (8) to (10):

Wherein (3), Q has the _{formula: -C 6 H 4 -, -} CONH-C 6 H 4 -NHCO -, - NHCO-C 6 H 4 -CONH -, - O-C 6 H 4 -CO _{-C 6 H 4 -O -, -} OCO-C 6 H 4 -COO -, - OCO-C 6 H 4 -C 6 H 4 -COO -, - OCO -, - NC 6 H 5 -, - CO- _{C 4 H 8 N 2 -CO -} , - C 13 H 10 -, - O -, - S -, - CO -, - CONH -, - SO 2 -, - C (CF 3) 2 -, - C ( _{, - - CH 3) 2 CH} 2 -, - (CH 2) 2 -, - (CH 2) 3 -, - (CH 2) 4 -, - (CH 2) 5 -, - O-C 6 H 4 _{-C (CH 3) 2 -C 6} H 4 -O -, - O-C 6 H 4 -SO 2 -C 6 H 4 -O -, - C (CH 3) 2 -C 6 H 4 -C ( CH _{3) -, - O-C 6 H} 4 -C 6 H 4 -O- and _{-O-C 6} H 4 -O- in indicates one selected from the group consisting of groups represented by,
R ⁶ in formula (10) represents one selected from the group consisting of a hydrogen atom, a fluorine atom, a methyl group, an ethyl group, and a trifluoromethyl group. ]
At least one of the groups represented by

Moreover, the polyimide of this invention contains 2 or more types of repeating units represented by General formula (1) as mentioned above. Then, as at least one of repeating units represented by such two or more of the general formula (1), a group R ¹⁰ in the general formula (1) is represented by the general formula (2) Containing the repeating unit (A). That is, the polyimide of this invention contains the repeating unit (A) which is represented by general formula (1) and in which R ¹⁰ is a group represented by the above general formula (2). Thus, the polyimide of the present invention is a repeating unit represented by the above general formula (1) and contains two or more kinds of repeating units having different types of R ¹⁰ , and at least 1 of them. It contains the repeating unit (A) as a seed. By including such a repeating unit (A) in combination with a repeating unit represented by the general formula (1) other than the repeating unit (A), it is possible to further improve the hardness of the polyimide. It becomes possible to have higher hardness while having sufficiently high heat resistance and transparency.

Moreover, in the polyimide of this invention containing 2 or more types of repeating units represented by general formula (1), as the repeating units represented by general formula (1) other than the repeating unit (A) (the above repeating units) The repeating unit represented by the general formula (1) used in combination with (A) is not particularly limited, and R ¹⁰ is a group other than the group represented by the general formula (2) ( The repeating unit represented by 1) can be appropriately used.

In the present invention, among the two or more types of repeating units contained in the polyimide, at least one of the repeating units other than the repeating unit (A) is such that R ¹⁰ in the formula (1) is the above. The repeating unit (B) that is any one of the groups represented by the general formulas (3) to (4) is more preferable. The repeating unit (B) represented by the general formula (1) and in which R ¹⁰ is any one of the groups represented by the above general formulas (3) to (4) By using in combination with the unit (A), it is possible to obtain a more excellent polyimide from the viewpoint of a balance of high heat resistance, colorless transparency, good solubility, and high hardness.

Moreover, such repeating units (B), high heat resistance, colorless transparency, good solubility, in view of high hardness, R ¹⁰ in the formula (1) is represented by the general formula (3) Q in formula (3) is —O—C ₆ H ₄ —SO ₂ —C ₆ H ₄ —O—, —O—C ₆ H ₄ —O—, —O—, —CONH—. , —C (CF ₃ ) ₂ — and —O—C ₆ H ₄ —C (CH ₃ ) ₂ —C ₆ H ₄ —O—. Repeating unit (B-1): The repeating unit (B-2) in which R ¹⁰ in the general formula (1) is a group represented by the general formula (4) is more preferable. Further, as the repeating unit (B-1), from the viewpoint of the solubility of the polyimide of the formula (3) in Q is _{-O-C 6 H 4 -SO 2} -C 6 H 4 -O -, - O what is one selected from the group consisting of groups represented by -C ₆ H ₄ -O- is more preferable. When R ¹⁰ in the repeating unit (B-2) is a group represented by the general formula (4), both of the two bonds in the general formula (4) are para-positions of the benzene ring. (The group represented by the general formula (4) is a group derived from FDA described later).

  Moreover, in the polyimide of this invention, it is preferable that content of the said repeating unit (A) is 25-75 mol% by molar ratio with respect to the total amount of the repeating unit represented by the said General formula (1), 30- More preferably, it is 60 mol%, and still more preferably 30-50 mol%. If the content of such a repeating unit (A) is less than the lower limit, it tends to be difficult to sufficiently improve the hardness of the polyimide. On the other hand, if the upper limit is exceeded, the solubility of the polyimide decreases, and the polyimide solution It tends to be difficult to obtain (varnish).

  Furthermore, in the polyimide of this invention, when it contains the said repeating unit (B), content of the said repeating unit (B) is 25-25 by the molar ratio with respect to the total amount of the repeating unit represented by the said General formula (1). It is preferably 75 mol%, more preferably 40 to 70 mol%, still more preferably 50 to 70 mol%. When the content of such a repeating unit (B) is less than the lower limit, the solubility of the polyimide tends to decrease, and when it exceeds the upper limit, the hardness of the polyimide tends to be sufficiently improved. .

  Moreover, in the polyimide of this invention, when it contains the said repeating unit (B), the total amount of the said repeating unit (A) and the said repeating unit (B) is represented by General formula (1) contained in a polyimide. It is preferably 90 mol% or more, more preferably 95 to 100 mol%, based on the total amount of repeating units (including the repeating unit (A) and the repeating unit (B)), 98 More preferably, it is -100 mol%. When the total amount of the repeating unit (A) and the repeating unit (B) is less than the lower limit, it is difficult to obtain a more excellent polyimide in terms of a balance of high heat resistance, colorless transparency, good solubility, and high hardness. It tends to be. Moreover, the repeating unit represented by General formula (1) contained in the polyimide of this invention consists of only 2 types of the said repeating unit (A) and the said repeating unit (B) from a compatible viewpoint of a polyimide. Is particularly preferred.

  Moreover, in the polyimide of this invention, what contains 40 mol% or more of repeating units represented by the said General formula (1) is preferable. Furthermore, in the polyimide of this invention, what mainly contains the repeating unit represented by the said General formula (1) (more preferably the total amount of the repeating unit represented by the said General formula (1) is with respect to all the repeating units. 50 to 100 mol% (more preferably 70 to 100 mol%, particularly preferably 80 to 100 mol%, most preferably 90 to 100 mol%). Such polyimide may contain other repeating units as long as the effects of the present invention are not impaired. Such other repeating units are not particularly limited, and are known repeating units that can be used as polyimide repeating units (for example, derived from 1,2,4,5-cyclohexanetetracarboxylic dianhydride (HPMDA)). And the like.

  The polyimide of the present invention preferably has a 5% weight loss temperature of 400 ° C. or higher, more preferably 450 to 550 ° C. If such a 5% weight loss temperature is less than the lower limit, sufficient heat resistance tends to be difficult to achieve, and if it exceeds the upper limit, it tends to be difficult to produce a polyimide having such characteristics. It is in. In addition, such 5% weight reduction temperature is heated gradually from 40 ° C. as a measurement start temperature after raising the temperature from room temperature (25 ° C.) to 40 ° C. while flowing nitrogen gas in a nitrogen gas atmosphere, It can be determined by measuring the temperature at which the weight of the sample used is reduced by 5%.

  Moreover, as such a polyimide, that whose glass transition temperature (Tg) is 250 degreeC or more is preferable, and the thing of 300-500 degreeC is more preferable. If the glass transition temperature (Tg) is less than the lower limit, sufficient heat resistance tends to be difficult to achieve, and if it exceeds the upper limit, it tends to be difficult to produce a polyimide having such characteristics. It is in. Such a glass transition temperature (Tg) can be measured by a tensile mode using a thermomechanical analyzer (trade name “TMA8310” or “TMA8311” manufactured by Rigaku). That is, a thermomechanical analyzer (trade name “TMA8310” or “TMA8311” manufactured by Rigaku) is used as a measuring device, and a polyimide film having a size of 20 mm in length and 5 mm in width (the thickness of the film affects the measured value). It is not particularly limited because it is not a thing, but it is preferably 5 to 80 μm.) Is formed as a measurement sample, under a nitrogen atmosphere, in a tensile mode (49 mN), a temperature rising rate of 5 ° C./min. Is used to obtain a TMA curve, and extrapolate the curve before and after the inflection point of the TMA curve resulting from the glass transition.

  Furthermore, such a polyimide preferably has a softening temperature of 300 ° C. or higher, more preferably 350 to 550 ° C. If the softening temperature is less than the lower limit, sufficient heat resistance tends to be difficult to achieve, and if it exceeds the upper limit, it tends to be difficult to produce a polyimide having such characteristics. Such a softening temperature can be measured in a penetration mode using a thermomechanical analyzer (trade name “TMA8310” or “TMA8311” manufactured by Rigaku). In measurement, since the sample size (vertical, horizontal, thickness, etc.) does not affect the measured value, the thermomechanical analyzer (trade name “TMA8310” or “TMA8311” manufactured by Rigaku) to be used is used. What is necessary is just to adjust the size of a sample suitably to the size which can be mounted in a tool.

  Moreover, as such a polyimide, a thing with a thermal decomposition temperature (Td) of 450 degreeC or more is preferable, and a 480-600 degreeC thing is more preferable. If such a thermal decomposition temperature (Td) is less than the lower limit, sufficient heat resistance tends to be difficult to achieve, and if it exceeds the upper limit, it is difficult to produce a polyimide having such characteristics. There is a tendency. In addition, such a thermal decomposition temperature (Td) was measured using a TG / DTA220 thermogravimetric analyzer (manufactured by SII Nanotechnology Co., Ltd.) in a nitrogen atmosphere under a heating rate of 10 ° C./min. It can be determined by measuring the temperature at the intersection of the tangent lines drawn on the decomposition curve before and after thermal decomposition under the conditions of

  Moreover, in the polyimide of this invention, it is preferable to have the hardness of 2B-9H in pencil hardness, and it is more preferable to have the hardness of HB-5H. If the hardness is less than the lower limit, it tends to be difficult to achieve sufficient hardness, and if the upper limit is exceeded, it tends to be difficult to make a colorless and transparent polyimide that exceeds such characteristics. It is in. In addition, such a value of pencil hardness can be obtained by measuring in accordance with a method defined in JIS K5600-5-4 issued in 1999.

  Furthermore, as a number average molecular weight (Mn) of such a polyimide, it is preferable that it is 1000-1 million in polystyrene conversion, and it is more preferable that it is 10000-500000. If such a number average molecular weight is less than the lower limit, it is difficult to achieve sufficient heat resistance, it does not sufficiently precipitate from the polymerization solvent during production, and it tends to be difficult to obtain polyimide efficiently, When the upper limit is exceeded, the viscosity increases, and it takes a long time to dissolve or requires a large amount of solvent, which tends to make processing difficult.

  Moreover, as a weight average molecular weight (Mw) of such a polyimide, it is preferable that it is 1000-5 million in polystyrene conversion. Moreover, as a lower limit of the numerical range of such a weight average molecular weight (Mw), it is more preferable that it is 5000, It is further more preferable that it is 10,000, It is especially preferable that it is 20000. Moreover, as an upper limit of the numerical range of a weight average molecular weight (Mw), it is more preferable that it is 5000000, It is further more preferable that it is 500,000, It is especially preferable that it is 100,000. If such a weight average molecular weight is less than the lower limit, it is difficult to achieve sufficient heat resistance, and does not sufficiently precipitate from the polymerization solvent during production, and it tends to be difficult to obtain polyimide efficiently, When the upper limit is exceeded, the viscosity increases, so that it takes a long time to dissolve or a large amount of solvent is required, which tends to make processing difficult.

  Furthermore, the molecular weight distribution (Mw / Mn) of such a polyimide is preferably 1.1 to 5.0, and more preferably 1.5 to 3.0. If the molecular weight distribution is less than the lower limit, it tends to be difficult to produce, while if it exceeds the upper limit, it tends to be difficult to obtain a uniform film. In addition, the molecular weight (Mw or Mn) and molecular weight distribution (Mw / Mn) of such polyimide are measured by a gel permeation chromatography (GPC) measuring device (Degasser: DG-2080-54 manufactured by JASCO, Liquid pump: JASCO PU-2080, interface: JASCO LC-NetII / ADC, column: Shodex GPC column KF-806M (× 2), column oven: JASCO 860-CO, RI detector : RI-2031 manufactured by JASCO, column temperature of 40 ° C., and data measured using a chloroform solvent (flow rate: 1 mL / min.) Can be obtained by conversion with polystyrene.

  Moreover, such a polyimide preferably has a linear expansion coefficient (CTE) of 0 to 100 ppm / K, and more preferably 10 to 70 ppm / K. When such a linear expansion coefficient exceeds the upper limit, peeling tends to occur due to thermal history when combined with a metal or inorganic material having a linear expansion coefficient range of 5 to 20 ppm / K. Moreover, when the linear expansion coefficient is less than the lower limit, the solubility and the film characteristics tend to be lowered.

  As a method for measuring the linear expansion coefficient of such polyimide, the method described below is adopted. That is, first, a polyimide film having a size of 20 mm in length and 5 mm in width (thickness of the film is not particularly limited because it does not affect the measured value, but is preferably 5 to 80 μm). Using a thermomechanical analyzer (trade name “TMA8310” or “TMA8311” manufactured by Rigaku) as a measuring device, a tensile mode (49 mN), a heating rate of 5 ° C. / The temperature was raised from room temperature to 200 ° C. (first temperature increase), allowed to cool to 30 ° C. or less, then heated from that temperature to 400 ° C. (second temperature increase), The change in the length of the sample in the vertical direction at the time of temperature rise is measured. Next, using the TMA curve obtained by the measurement at the time of the second temperature increase (measurement when the temperature is raised from the temperature at the time of standing to 400 ° C.), 1 in the temperature range of 100 ° C. to 200 ° C. The average value of the change in length per degree C is obtained, and the obtained value is measured as the linear expansion coefficient of polyimide. Thus, as the linear expansion coefficient of the polyimide of the present invention, a value obtained by obtaining the average value of the change in length per 1 ° C. in the temperature range of 100 ° C. to 200 ° C. based on the TMA curve is adopted. To do.

  Moreover, as such a polyimide, it is preferable that transparency is sufficiently high when a film is formed, and the total light transmittance is 80% or more (more preferably 85% or more, particularly preferably 87% or more). ) Is more preferable. Such total light transmittance can be easily achieved by appropriately selecting the type of polyimide or the like.

  Moreover, as such a polyimide, the thing whose haze (turbidity) is 5-0 (more preferably 4-0, especially preferably 3-0) from a viewpoint of obtaining a more highly colorless transparency is more. preferable. If the haze value exceeds the upper limit, it tends to be difficult to achieve a higher level of colorless transparency.

  Further, as such a polyimide, those having a yellowness (YI) of 5 to 0 (more preferably 4 to 0, particularly preferably 3 to 0) are obtained from the viewpoint of obtaining a higher degree of colorless transparency. preferable. When such yellowness exceeds the upper limit, it tends to be difficult to achieve a higher level of colorless transparency.

  Such total light transmittance, haze (turbidity) and yellowness (YI) are measured by a product name “Haze Meter NDH-5000” manufactured by Nippon Denshoku Industries Co., Ltd. or manufactured by Nippon Denshoku Industries Co., Ltd. The total light transmittance and haze were measured with a product name “Spectral Color Meter SD6000” (trade name “Haze Meter NDH-5000” manufactured by Nippon Denshoku Industries Co., Ltd.). The value measured by using a film made of polyimide having a thickness of 5 to 100 μm as a sample for measurement can be adopted. In addition, the vertical and horizontal sizes of the measurement sample may be any size that can be arranged at the measurement site of the measurement apparatus, and the vertical and horizontal sizes may be appropriately changed. In addition, such total light transmittance is calculated | required by measuring based on JISK7361-1 (issued in 1997), and a haze (turbidity) performs the measurement based on JISK7136 (issued in 2000). The yellowness (YI) is obtained by performing measurement in accordance with ASTM E313-05 (issued in 2005).

  In addition, the polyimide of the present invention includes a film for a flexible wiring board, a heat resistant insulating tape, a wire enamel, a semiconductor protective coating agent, a liquid crystal alignment film, a transparent conductive film for organic EL, a film for organic EL lighting, and a flexible board. Film, flexible organic EL substrate film, flexible transparent conductive film, organic thin film solar cell transparent conductive film, dye-sensitized solar cell transparent conductive film, flexible gas barrier film, touch panel film, flexible display front It is particularly useful as a material for producing films, back films for flexible displays, and the like.

  Moreover, such a polyimide can be suitably manufactured by the manufacturing method of the polyimide of this invention mentioned later. Therefore, as such a polyimide, it is preferable that it is obtained by the manufacturing method of the polyimide of this invention mentioned later.

[Production Method of Polyimide of the Present Invention]
The method for producing the polyimide of the present invention includes:
In the presence of a polymerization solvent, at least one tetracarboxylic dianhydride selected from the compound represented by the general formula (5A) and the compound represented by the general formula (5B);
The following general formula (6):
^{_{H 2 N-R 10 -NH 2}} (6)
[In formula (6), R ¹⁰ represents an arylene group having 6 to 40 carbon atoms. ]
4,4′-diamino-2,2′-dimethylbiphenyl which contains two or more aromatic diamines represented by general formula (7) and at least one of the aromatic diamines is represented by the general formula (7). A mixture of certain aromatic diamines;
By reacting
Containing two or more repeating units represented by the general formula (1), and
It is characterized in that at least one of the two or more kinds of repeating units obtains a polyimide in which R ¹⁰ in the formula (1) is a repeating unit (A) which is a group represented by the general formula (2). It is a method.

As a preferred embodiment of the method for producing a polyimide of the present invention, first, a case where the compound represented by the above general formula (5A) is used as a tetracarboxylic dianhydride will be described. As a method for producing the polyimide of the present invention when such a compound represented by the general formula (5A) is used, for example, in the presence of a polymerization solvent, the compound represented by the above general formula (5A) (tetracarboxylic Acid dianhydride) and two or more aromatic diamines represented by the general formula (6), and at least one of the aromatic diamines is represented by the general formula (7) 4, Reacting with a mixture of aromatic diamines which are 4′-diamino-2,2′-dimethylbiphenyl,
The following general formula (11A):

Wherein ^{(11A), R 1, R} 2, R 3 are each independently a hydrogen atom, it represents one selected from the group consisting of alkyl groups and fluorine atom having 1 to 10 carbon ^{atoms, R 10} is A C6-C40 arylene group is shown, n shows the integer of 0-12. ]
A group in which R ¹⁰ in the formula (11A) is a group represented by the above general formula (2), containing at least two types of repeating units represented by formula (11). A step (I) of obtaining a polyamic acid as a repeating unit (A ′),
The polyamic acid is imidized to contain two or more repeating units represented by the general formula (1), and at least one of the two or more repeating units is represented by the formula (1) Step (II) for obtaining a polyimide which is a repeating unit (A) in which R ¹⁰ is a group represented by the general formula (2);
(When such a production method including steps (I) and (II) is adopted, X in the formula (1) in the obtained polyimide is represented by the general formula (I-1)). Become the basis). Hereinafter, steps (I) and (II) that can be suitably used in the method for producing a polyimide of the present invention will be described.

(Step (I): Step of obtaining polyamic acid)
Step (I) contains two or more types of tetracarboxylic dianhydride represented by the above general formula (5A) and aromatic diamine represented by the above general formula (6) in the presence of a polymerization solvent, and The polyamide is reacted with a mixture of aromatic diamines in which at least one of the aromatic diamines is 4,4′-diamino-2,2′-dimethylbiphenyl represented by the general formula (7). This is a step of obtaining an acid.

Regarding the tetracarboxylic dianhydride represented by the general formula (5A), R ¹ , R ² and R ³ in the formula (5A) are each independently a hydrogen atom or an alkyl having 1 to 10 carbon atoms. It is 1 type selected from the group which consists of group and a fluorine atom, and n is an integer of 0-12. ^R 1 in the general formula ^{(5A), R 2, R} 3, n is, ^R 1 in the general formula described in the polyimide of the present invention as described above ^{(I-1), R 2} , R 3, n is the same as that described above, and preferable examples thereof are also the same as preferable examples of R ¹ , R ² , R ³ and n in the general formula (I-1).

  Moreover, it does not restrict | limit especially as a method for manufacturing the tetracarboxylic dianhydride represented by General formula (5A) used for such a process (I), A well-known method can be employ | adopted suitably. For example, the methods described in Synthesis Example 1, Example 1 and Example 2 of International Publication No. 2011/099518 can be appropriately employed.

Further, with respect to the aromatic diamine used in step (I), general formula (6) R ¹⁰ in is the same as the R ¹⁰ in the general formula (1) described in the polyimide of the present invention described above, the The preferred one is also the same as the preferred one for R ^{10 in} the general formula (1). It does not restrict | limit especially as a method for manufacturing such an aromatic diamine, A well-known method is employable suitably. Moreover, you may use a commercially available thing suitably as such aromatic diamine.

  Moreover, the mixture of the aromatic diamine used for process (I) contains 2 or more types of aromatic diamine represented by General formula (6). And as at least 1 sort (s) of such 2 or more types of aromatic diamine represented by General formula (6), 4,4'- diamino-2,2 'represented by the said General formula (7) -Contains dimethylbiphenyl. Thus, by including 4,4′-diamino-2,2′-dimethylbiphenyl in combination with another aromatic diamine, the resulting polyimide has a repeating unit represented by the above general formula (1). Two or more types can be contained, and one of them can be used as the repeating unit (A). Therefore, by including 4,4′-diamino-2,2′-dimethylbiphenyl in combination with other aromatic diamines, it is possible to further improve the hardness of the resulting polyimide, and the polyimide to be produced is sufficient. In addition, it is possible to have higher hardness while having high heat resistance and transparency.

The aromatic diamine represented by the general formula (6) other than 4,4′-diamino-2,2′-dimethylbiphenyl to be contained in the mixture of aromatic diamines is not particularly limited, and R ¹⁰ is An aromatic diamine represented by the general formula (6) that is an arylene group having 6 to 40 carbon atoms and other than the group represented by the general formula (2) can be appropriately used. .

In the mixture of aromatic diamines, the aromatic diamine represented by the general formula (6) other than 4,4′-diamino-2,2′-dimethylbiphenyl is such that R ¹⁰ in the formula (6) is the above. The aromatic diamine (I) which is any one of the groups represented by the general formulas (3) to (4) is preferable. By using such aromatic diamine (I) in combination with 4,4′-diamino-2,2′-dimethylbiphenyl, it has an excellent balance of high heat resistance, colorless transparency, good solubility, and high hardness. Can be obtained.

Further, Examples of the aromatic diamine (I), high heat resistance, colorless transparency, good solubility, from the viewpoint to further improve the balance of the high hardness, the general formula (6) R ¹⁰ is the formula in A group represented by (3), and Q in formula (3) is —O—C ₆ H ₄ —SO ₂ —C ₆ H ₄ —O—, —O—C ₆ H ₄ —O—, _{-O -, - C (CF 3} ) 2 -, - O-C 6 H 4 -C (CH 3) 2 -C 6 H 4 -O- in one selected from the group consisting of groups represented by Certain aromatic diamines (I-1); and aromatic diamines (I-2) in which R ¹⁰ in the general formula (6) is a group represented by the general formula (4) are more preferable. Further, examples of the aromatic diamine (I-1), from the viewpoint of the solubility of the polyimide of the formula (3) in Q is _{-O-C 6 H 4 -SO 2} -C 6 H 4 -O -, - _{O-C 6 H} 4 is more preferable is one selected from the group consisting of groups represented by -O, equation (3) Q in is _{-O-C 6 H 4 -SO 2} -C 6 _{H 4 -O -, - O-} C 6 shall H 4 is one selected -O- from the group consisting of groups represented by is more preferable.

  In the aromatic diamine mixture, the 4,4′-diamino-2,2′-dimethylbiphenyl content is 25 in terms of a molar ratio to the total amount of the aromatic diamine represented by the general formula (6). It is preferable that it is -75 mol%, It is more preferable that it is 30-60 mol%, It is still more preferable that it is 30-50 mol%. If the content of 4,4′-diamino-2,2′-dimethylbiphenyl is less than the lower limit, it tends to be difficult to sufficiently improve the hardness of the finally obtained polyimide, When the upper limit is exceeded, the solubility of the polyamic acid is lowered, and the choice of usable solvents tends to be very small.

  Further, in the mixture of aromatic diamines, when the aromatic diamine (I) is contained, the content of the aromatic diamine (I) is based on the total amount of the aromatic diamine represented by the general formula (6). The molar ratio is preferably 25 to 75 mol%, more preferably 40 to 70 mol%, and still more preferably 50 to 70 mol%. If the content of the aromatic diamine (I) is less than the lower limit, the solubility of the polyamic acid is reduced, and the choice of usable solvents tends to be very small. It tends to be difficult to sufficiently improve the hardness.

  Further, in the mixture of aromatic diamines, when the aromatic diamine (I) is contained, the total amount of the 4,4′-diamino-2,2′-dimethylbiphenyl and the aromatic diamine (I) is The amount of the aromatic diamine represented by the general formula (6) is preferably 90 mol% or more, more preferably 95 to 100 mol%, and 98 to 100 mol%. Further preferred. If the total amount of 4,4′-diamino-2,2′-dimethylbiphenyl and the aromatic diamine (I) is less than the lower limit, characteristics such as high heat resistance, colorless transparency, good solubility, and high hardness are obtained. It tends to be difficult to obtain a polyimide having a better balance. The mixture of aromatic diamines is preferably composed only of the aromatic diamine represented by the above general formula (6) from the viewpoint of compatibility of the polyimide, and 4,4′-diamino-2, It is particularly preferable to consist of only two kinds of 2′-dimethylbiphenyl and the aromatic diamine (I).

  Moreover, as a polymerization solvent used for process (I), it is an organic solvent which can melt | dissolve both the mixture of the tetracarboxylic dianhydride represented by the said general formula (5A), and the said aromatic diamine. Is preferred. Examples of such an organic solvent include N-methyl-2-pyrrolidone, N, N-dimethylacetamide, N, N-dimethylformamide, dimethylsulfoxide, γ-butyrolactone, propylene carbonate, tetramethylurea, 1,3- Aprotic polar solvents such as dimethyl-2-imidazolidinone, hexamethylphosphoric triamide, pyridine; phenolic solvents such as m-cresol, xylenol, phenol, halogenated phenol; tetrahydrofuran, dioxane, cellosolve, glyme And ether solvents such as benzene, toluene and xylene, ketone solvents such as cyclopentanone and cyclohexanone, and nitrile solvents such as acetonitrile and benzonitrile. Such organic solvents may be used singly or in combination of two or more.

  Further, as such a polymerization solvent, it is more preferable to use an aprotic polar solvent from the viewpoint of solubility in tetracarboxylic dianhydride and aromatic diamine, and among them, N, N-dimethylacetamide and γ- It is particularly preferable to use butyrolactone in combination. Thus, when N, N-dimethylacetamide and γ-butyrolactone are used in combination as the polymerization solvent, these are excellent in solubility in tetracarboxylic dianhydride and aromatic diamine. It becomes possible to make the polymerization reaction proceed more efficiently (becomes a state in which the reaction is more likely to proceed), thereby making it possible to obtain a polyamic acid varnish having a high degree of polymerization in a shorter time.

  In step (I), the ratio of the tetracarboxylic dianhydride represented by the general formula (5A) and the mixture of the aromatic diamines is the aromatic ratio in the mixture of the aromatic diamines. It is preferable that the acid anhydride group of the tetracarboxylic dianhydride represented by the general formula (5A) is 0.2 to 2 equivalents relative to 1 equivalent of the amino group of the diamine, and 0.3 to 1 More preferably, it is 2 equivalents. If the use ratio is less than the lower limit, the polymerization reaction does not proceed efficiently, and a high molecular weight polyamic acid tends not to be obtained. There is no tendency.

  Furthermore, as the usage-amount of the said polymerization solvent (organic solvent) in process (I), the total amount of the mixture of the said aromatic diamine and the tetracarboxylic dianhydride represented by the said General formula (5A) is reaction solution. The amount is preferably 0.1 to 50% by mass (more preferably 10 to 30% by mass) with respect to the total amount. If the amount of the organic solvent used is less than the lower limit, the polyamic acid tends not to be obtained efficiently. On the other hand, if it exceeds the upper limit, stirring tends to be difficult due to the increase in viscosity.

  Further, in the step (I), when the tetracarboxylic dianhydride represented by the general formula (5A) is reacted with the mixture of the aromatic diamine, a polyamic acid having a high reaction rate and a high polymerization degree is added. From the viewpoint of obtaining, a basic compound may be further added to the organic solvent. Examples of such basic compounds include, but are not limited to, triethylamine, tetrabutylamine, tetrahexylamine, 1,8-diazabicyclo [5.4.0] -undecene-7, pyridine, isoquinoline, α-picoline, and the like. Can be mentioned. Moreover, it is preferable that the usage-amount of such a basic compound shall be 0.001-10 equivalent with respect to 1 equivalent of tetracarboxylic dianhydrides represented with the said general formula (5A), 0.01- More preferably, it is 0.1 equivalent. If the amount of such a basic compound used is less than the lower limit, the effect of addition tends to be lost. On the other hand, if it exceeds the upper limit, it tends to cause coloring or the like.

  Moreover, in process (I), the reaction temperature at the time of making the tetracarboxylic dianhydride represented by the said general formula (5A) and the mixture of the said aromatic diamine react is making these compounds react. What is necessary is just to adjust suitably to possible temperature, and it does not restrict | limit in particular, It is preferable to set it as -20-450 degreeC according to the case, It is more preferable to set it as -20-400 degreeC, It is set as -20-200 degreeC. Is more preferable, and 0 to 100 ° C. is particularly preferable. In addition, as a method of reacting the tetracarboxylic dianhydride represented by the general formula (5A) that can be employed in such step (I) with the mixture of the aromatic diamine, tetracarboxylic dianhydride is used. A method capable of performing a polymerization reaction between the product and the aromatic diamine can be used as appropriate, and is not particularly limited. For example, a mixture of aromatic diamines can be used at atmospheric pressure and in an inert atmosphere such as nitrogen, helium, and argon. After dissolving in a solvent, a method of adding the tetracarboxylic dianhydride represented by the general formula (2) at the reaction temperature and then reacting for 10 to 48 hours may be adopted. If the reaction temperature or reaction time is less than the lower limit, it tends to be difficult to cause sufficient reaction. On the other hand, if the upper limit is exceeded, the probability of mixing a substance (such as oxygen) that degrades the polymer increases and the molecular weight increases. It tends to decrease.

Further, in this way, the repeating unit represented by the general formula (11A) is contained in two or more types, and at least one of the two or more repeating units is R in the formula (11A). A polyamic acid in which ¹⁰ is a repeating unit (A ′) which is a group represented by the general formula (2) can be obtained. ^{Incidentally, R 1, R 2, R} 3, R 10 and n in the general formula (11A) is, ^R 1 in the general formula (1) described in the polyimide of the present invention described ^{above, R} 2, R ³ , R ¹⁰ and n are the same as those described above, and preferable ones thereof are also the same as those of R ¹ , R ² , R ³ , R ¹⁰ and n in the general formula (1).

In addition, as described above, the polyamic acid includes a repeating unit (A ′) that is represented by the general formula (11A) and in which R ¹⁰ is a group represented by the general formula (2). It contains. Such a repeating unit (A ′) is composed of a tetracarboxylic dianhydride represented by the general formula (5A) and 4,4′-diamino-2,2′- represented by the general formula (7). It is a repeating unit formed from the reaction of dimethylbiphenyl.

Moreover, in the said polyamic acid containing 2 or more types of repeating units represented by general formula (11A), as a repeating unit represented by general formula (11A) other than said repeating unit (A ') (the said repeating unit) The repeating unit represented by the general formula (11A) used in combination with (A ′) is not particularly limited, and R ¹⁰ is an arylene group having 6 to 40 carbon atoms and the above general formula (2 The repeating unit represented by the general formula (11A) that is other than the group represented by

Further, in the polyamic acid, at least one of the repeating units other than the repeating unit (A ′) among the two or more kinds of repeating units to be contained is such that R ¹⁰ in the formula (11A) is the above general formula. The repeating unit (B ′) that is any one of the groups represented by the formulas (3) to (4) is preferable. The repeating unit (B ′) represented by the general formula (11A) and R ¹⁰ in the formula is any one of the groups represented by the general formulas (3) to (4), By using in combination with the repeating unit (A ′), a polyimide film that is superior in terms of a balance between high heat resistance, colorless transparency, and high hardness is obtained when it is derived into a polyimide film using polyamic acid. It becomes possible.

In addition, as such a repeating unit (B ′), R ¹⁰ in the general formula (11A) is selected from the viewpoint of the balance between high heat resistance, colorless transparency, and high hardness of the polyimide film derived from polyamic acid. the formula a group represented by (3) in the formula (3) Q is _{-O-C 6 H 4 -SO 2} -C 6 H 4 -O -, - O-C 6 H 4 -O 1 selected from the group consisting of —, —O—, —C (CF ₃ ) ₂ —, —O—C ₆ H ₄ —C (CH ₃ ) ₂ —C ₆ H ₄ —O—. The repeating unit (B′-1) which is a seed; and the repeating unit (B′-2) in which R ¹⁰ in the general formula (1) is a group represented by the general formula (4) are more preferable. In addition, as the repeating unit (B′-1), Q in the formula (3) is —O—C ₆ H ₄ —SO ₂ —C ₆ H from the viewpoint of solubility of polyimide derived from polyamic acid. _{4 -O -, - O-C} 6 shall H 4 is one selected -O- from the group consisting of groups represented by is more preferable.

  Moreover, in the said polyamic acid, it is preferable that content of the said repeating unit (A ') is 25-75 mol% by molar ratio with respect to the total amount of the repeating unit represented by the said general formula (11A), 30- More preferably, it is 60 mol%, and still more preferably 30-50 mol%. If the content of such a repeating unit (A ′) is less than the lower limit, it tends to be difficult to sufficiently improve the hardness of the polyimide. On the other hand, if the upper limit is exceeded, the solubility of the polyamic acid decreases, There is a tendency for the choice of usable solvents to be very small.

  Furthermore, in the said polyamic acid, when it contains the said repeating unit (B '), content of the said repeating unit (B') is 25 by molar ratio with respect to the total amount of the repeating unit represented by the said General formula (11A). It is preferable that it is -75 mol%, It is more preferable that it is 40-70 mol%, It is still more preferable that it is 50-70 mol%. If the content of such a repeating unit (B ′) is less than the lower limit, the solubility of the polyamic acid tends to be reduced, and the choice of usable solvents tends to be very small. It tends to be difficult to sufficiently improve the hardness.

  Moreover, in the said polyamic acid, when it contains the said repeating unit (B '), the total amount of the said repeating unit (A') and the said repeating unit (B ') contains general formula (11A) contained in a polyamic acid. ) Is preferably 90 mol% or more, and 95 to 100 mol% with respect to the total amount of the repeating units represented by (including the repeating unit (A ′) and the repeating unit (B ′)). Is more preferable, and it is still more preferable that it is 98-100 mol%. When the total amount of the repeating unit (A ′) and the repeating unit (B ′) is less than the lower limit, a polyimide film having an excellent balance of high heat resistance, colorless transparency, and high hardness is obtained when derived from polyamic acid. It tends to be difficult to obtain. In addition, the repeating unit represented by the general formula (11A) contained in the polyamic acid is the repeating unit from the viewpoint that when it is derived from polyamic acid, a more excellent polyimide film can be obtained in terms of colorless transparency. It is particularly preferable that the unit consists of only two types of unit (A ′) and repeating unit (B ′).

  Furthermore, in the polyamic acid, the polyamic acid mainly contains the repeating unit represented by the general formula (11A) (more preferably, the total amount of the repeating units represented by the general formula (11A) is based on the total repeating units. 50 to 100 mol% (more preferably 70 to 100 mol%, particularly preferably 80 to 100 mol%, most preferably 90 to 100 mol%) is preferable. Such a polyamic acid may contain other repeating units as long as the effects of the present invention are not impaired. Such other repeating unit is not particularly limited and may be a known repeating unit that can be used as a repeating unit for polyamic acid (for example, 1,2,4,5-cyclohexanetetracarboxylic dianhydride (HPMDA)). Derived repeating units).

  Moreover, as such a polyamic acid, it is preferable that intrinsic viscosity [(eta)] is 0.05-3.0 dL / g, and it is more preferable that it is 0.1-2.0 dL / g. When the intrinsic viscosity [η] is smaller than 0.05 dL / g, when a film-like polyimide is produced using the intrinsic viscosity [η], the resulting film tends to be brittle, while 3.0 dL / g is reduced. When it exceeds, the viscosity is too high and the processability is lowered, and for example, when a film is produced, it is difficult to obtain a uniform film. Such intrinsic viscosity [η] can be measured as follows. That is, first, N, N-dimethylacetamide is used as a solvent, and the polyamic acid is dissolved in the N, N-dimethylacetamide so as to have a concentration of 0.5 g / dL, and a measurement sample (solution) is obtained. obtain. Next, using the measurement sample, the viscosity of the measurement sample is measured using a kinematic viscometer under a temperature condition of 30 ° C., and the obtained value is adopted as the intrinsic viscosity [η]. As such a kinematic viscometer, THOMAS SCIENTIFIC CO. The brand name “KINEMATIC VISCOMETER TV-5S” manufactured by the company is used.

  In addition, when the polyimide obtained by this invention shall contain another repeating unit with the repeating unit represented by the said General formula (1), for example in process (I), the said General formula ( Other tetracarboxylic dianhydrides may be used together with the tetracarboxylic dianhydride represented by 5A), and these may be reacted with the mixture of the aromatic diamines, or represented by the general formula (11A). These diamines may be used together with other diamines to react with tetracarboxylic dianhydrides represented by the above general formula (5A), and furthermore, such other tetracarboxylic dianhydrides. Both the product and other diamines may be used as appropriate to make polyimide. As such other tetracarboxylic dianhydrides and other aromatic diamines, known ones used for the production of polyimide can be used as appropriate.

(Step (II): Step of obtaining polyimide)
In step (II), the polyamic acid is imidized to contain two or more repeating units represented by the general formula (1), and at least one of the two or more repeating units is: A polyimide in which R ¹⁰ in formula (1) is a repeating unit (A) which is a group represented by the above general formula (2) (wherein X in formula (1) is the above general formula (I-1)) This is a process for obtaining a group to be represented.

  The imidization method of the polyamic acid is not particularly limited as long as it is a method capable of imidizing the polyamic acid, and a known method can be appropriately employed. For example, the polyamic acid can be used as a so-called condensing agent or the like. A method of imidizing by using an imidizing agent, a method of imidizing by subjecting the polyamic acid to a heating condition of 60 to 450 ° C. (more preferably 80 to 400 ° C.), etc. preferable.

  In such imidization, when adopting a method of imidizing the polyamic acid using an imidizing agent such as a so-called condensing agent, the polyamic acid of the present invention is imidized in a solvent in the presence of the condensing agent. It is preferable. As such a solvent, the thing similar to the polymerization solvent (organic solvent) used for the manufacturing method of the above-mentioned polyimide acid of the present invention can be used conveniently. Thus, when adopting a method for imidizing using an imidizing agent such as a so-called condensing agent, the polyamic acid is chemically imidized using an imidizing agent such as a condensing agent in the polymerization solvent. It is preferable to employ a step of obtaining the polyimide.

  In addition, in the case of imidizing by employing chemical imidization using an imidizing agent such as a condensing agent, the imidization step described in the step (II) is performed using a dehydrating condensing agent (carboxylic acid anhydride) as the condensing agent. More preferably, the polyamic acid is dehydrated and cyclized and imidized using a compound, carbodiimide, acid azide, active esterifying agent, etc.) and a reaction accelerator (tertiary amine, etc.). By adopting such a process, it is not always necessary to heat at high temperature during imidation, and it is also possible to obtain polyimide by imidization under low temperature conditions (more preferably at about 100 ° C. or less). It becomes.

  In the case of imidizing by employing such chemical imidization, the tetracarboxylic dianhydride represented by the general formula (5A) and the aromatic diamine in the polymerization solvent (organic solvent) according to the step (I) After obtaining a reaction liquid obtained by reacting with the mixture (reaction liquid containing a polyamic acid having a repeating unit represented by the above general formula (11A)), the reaction liquid is used as it is, and a condensing agent is used. The chemical imidization used may be applied. In addition, after implementing the step (I), the polyamic acid may be isolated, and the polyamic acid may be separately added to the polymerization solution before chemical imidization.

  In addition, the condensing agent used in the case of employing chemical imidization in such step (II) may be any one that can be used when condensing the polyamic acid into a polyimide, and the reaction described below. In combination with an accelerator, a known compound used as a so-called “imidizing agent” can be appropriately used. Such a condensing agent is not particularly limited, and examples thereof include carboxylic anhydrides such as acetic anhydride, propionic anhydride and trifluoroacetic anhydride, carbodiimides such as N, N′-dicyclohexylcarbodiimide (DCC), and diphenyl phosphoric acid. Examples thereof include acid azides such as azide (DPPA), active esterifying agents such as Castro reagent, and dehydrating condensation agents such as 2-chloro-4,6-dimethoxytriazine (CDMT). Among such condensing agents, acetic anhydride, propionic anhydride, and trifluoroacetic anhydride are preferable, acetic anhydride and propionic anhydride are more preferable, and acetic anhydride is still more preferable from the viewpoint of reactivity, availability, and practicality. Such condensing agents may be used alone or in combination of two or more.

  The reaction accelerator is not particularly limited as long as it can be used when the polyamic acid is condensed to form a polyimide, and a known compound can be appropriately used. Such a reaction accelerator can also function as an acid scavenger that supplements the acid by-produced during the reaction. Therefore, by using such a reaction accelerator, acceleration of the reaction and the reverse reaction due to the by-product acid are suppressed, and the reaction can proceed efficiently. Such a reaction accelerator is not particularly limited, but more preferably also serves as an acid scavenger, such as triethylamine, diisopropylethylamine, N-methylpiperidine, pyridine, collidine, lutidine, 2-hydroxypyridine, Tertiary amines such as 4-dimethylaminopyridine (DMAP), 1,4-diazabicyclo [2.2.2] octane (DABCO), diazabicyclononene (DBN), diazabicycloundecene (DBU), etc. be able to. Among such reaction accelerators, triethylamine, diisopropylethylamine, N-methylpiperidine, and pyridine are preferable from the viewpoint of reactivity, availability, and practicality, triethylamine, pyridine, and N-methylpiperidine are more preferable, and triethylamine, N -More preferred is methylpiperidine. Such reaction accelerators may be used alone or in combination of two or more.

  Also, for example, by adding a catalytic amount of a reaction accelerator (DMAP, etc.) and an azeotropic dehydrating agent (benzene, toluene, xylene, etc.), water generated when the polyamic acid becomes an imide is removed by azeotropic dehydration. It may be imidized. Thus, in the chemical imidization, an azeotropic dehydrating agent may be appropriately used together with the reaction accelerator. Such an azeotropic dehydrating agent is not particularly limited, and may be appropriately selected from known azeotropic dehydrating agents according to the type of material used in the reaction.

  Moreover, when chemically imidizing using such a condensing agent and reaction accelerator, the polyamic acid obtained after implementing step (I) is isolated from the viewpoint of more efficiently producing polyimide. Without reaction, the reaction solution obtained by reacting the mixture of the tetracarboxylic dianhydride represented by the general formula (5A) and the aromatic diamine in the polymerization solvent (organic solvent) (containing the polyamic acid) It is more preferable to employ a method in which the reaction solution is used as it is, and a condensing agent (imidizing agent) and a reaction accelerator are added to the reaction solution to imidize.

  Further, the temperature condition during such chemical imidation is preferably −40 ° C. to 200 ° C., more preferably −20 ° C. to 150 ° C., and further preferably 0 to 150 ° C. 50 to 100 ° C. is particularly preferable. If such a temperature exceeds the upper limit, an undesirable side reaction tends to proceed and polyimide cannot be obtained. On the other hand, if the temperature is lower than the lower limit, the reaction rate of chemical imidation decreases or the reaction itself does not proceed. Tend not to be obtained. Thus, when chemical imidization is employed, it is possible to imidize at a relatively low temperature range of −40 ° C. to 200 ° C., thereby reducing the environmental burden. It becomes.

  The reaction time for such chemical imidation is preferably 0.1 to 48 hours. If the reaction temperature or time is less than the lower limit, it is difficult to sufficiently imidize, and it tends to be difficult to deposit polyimide in the polymerization solvent. On the other hand, if the upper limit is exceeded, the polymer is deteriorated. There is a tendency that the mixing probability of the substance (oxygen, etc.) to be increased increases and the molecular weight decreases.

  The amount of such a condensing agent is not particularly limited, but is preferably 0.05 to 4.0 mol, preferably 1 to 2 mol, based on 1 mol of the repeating unit in the polyamic acid. Is more preferable. If the amount of such a condensing agent (imidizing agent) is less than the lower limit, the reaction rate of chemical imidization tends to decrease, or the reaction itself does not proceed sufficiently and polyimide cannot be obtained sufficiently, When the upper limit is exceeded, an undesirable side reaction proceeds, and thus polyimide cannot be obtained efficiently.

  The amount of the reaction accelerator used in the chemical imidation is not particularly limited, but is preferably 0.05 to 4.0 mol with respect to 1 mol of the repeating unit in the polyamic acid. More preferably, it is 2 mol. If the amount of the reaction accelerator used is less than the lower limit, the reaction rate of chemical imidization decreases, or the reaction itself does not proceed sufficiently and polyimide cannot be obtained sufficiently. On the other hand, it exceeds the upper limit. As a result, an undesirable side reaction proceeds, and thus polyimide cannot be obtained efficiently.

  In addition, as atmospheric conditions for performing such chemical imidization, from the viewpoint of preventing coloring due to oxygen in the air and molecular weight reduction due to water vapor in the air, an inert gas atmosphere such as nitrogen gas or under vacuum It is preferable that Moreover, it does not restrict | limit especially as pressure conditions at the time of performing such chemical imidation, However, It is preferable that it is 0.01 hPa-1 MPa, and it is more preferable that it is 0.1 hPa-0.3 MPa. If such pressure is less than the lower limit, the solvent, the condensing agent, and the reaction accelerator are gasified, the stoichiometry is lost, the reaction is adversely affected, and the reaction tends to be difficult to proceed sufficiently. On the other hand, when the upper limit is exceeded, an undesirable side reaction proceeds, or the solubility of the polyamic acid tends to decrease and precipitate.

  In the imidization in the step (II), as described above, the polyamic acid is subjected to a treatment (heating treatment) for heating under a temperature condition of 60 to 450 ° C. (more preferably 80 to 400 ° C.). It is also possible to adopt a method of making it. In the case of adopting such a heat treatment and imidizing method, the reaction tends to be delayed when the heating temperature is less than the lower limit, and on the other hand, when the upper limit is exceeded, coloring or thermal decomposition causes molecular weight. There is a tendency to decrease. Moreover, it is preferable that reaction time (heating time) in the case of employ | adopting the method to imidize by performing the said heat processing shall be 0.5 to 5 hours. If such a reaction time is less than the lower limit, it tends to be difficult to sufficiently imidize. On the other hand, if it exceeds the upper limit, it tends to be colored or decrease in molecular weight due to thermal decomposition.

  Moreover, when imidating by performing the said heat processing, in order to promote high molecular weight and imidation, you may utilize what is called a reaction accelerator. Examples of such reaction accelerators include known reaction accelerators (triethylamine, diisopropylethylamine, N-methylpiperidine, pyridine, collidine, lutidine, 2-hydroxypyridine, 4-dimethylaminopyridine (DMAP), 1,4-diazabicyclo. [2.2.2] A tertiary amine such as octane (DABCO), diazabicyclononene (DBN), diazabicycloundecene (DBU), etc.) may be used as appropriate. Of these reaction accelerators, triethylamine, diisopropylethylamine, N-methylpiperidine, and pyridine are preferable, and triethylamine, pyridine, and N-methylpiperidine are more preferable, and triethylamine is preferable from the viewpoints of reactivity, availability, and practicality. N-methylpiperidine is more preferred. Such reaction accelerators may be used alone or in combination of two or more. In addition, in the case of imidization by performing the heat treatment, the amount of the reaction accelerator used is not particularly limited. For example, 0.01 to 0.1 mol per 1 mol of the repeating unit in the polyamic acid. The amount is preferably 4.0 mol, more preferably 0.05 to 2.0 mol, and still more preferably 0.05 to 1.0 mol.

  Further, when a method including such steps (I) and (II) is used, and when a method of imidizing by applying the heat treatment during imidization is employed, the step (I ), The reaction solution obtained by reacting the mixture of the tetracarboxylic dianhydride and the aromatic diamine in an organic solvent without isolating the polyamic acid of the present invention (the polyamide) The reaction solution containing an acid) is used as it is, and after the solvent is removed by subjecting the reaction solution to evaporation removal (solvent removal treatment), imidization is performed by applying the heat treatment. May be. By the process of evaporating and removing the solvent, it is possible to isolate the polyamic acid in the form of a film or the like and then perform a heat treatment to obtain a polyimide in a desired form.

  The temperature condition in the method of evaporating and removing the solvent (solvent removing treatment) is preferably 0 to 180 ° C, more preferably 30 to 150 ° C. If the temperature condition in such a solvent removal treatment is less than the lower limit, it tends to be difficult to remove the solvent sufficiently by evaporation, whereas if the upper limit is exceeded, the solvent will boil and the film contains bubbles and voids. Tend to be. In this case, for example, in the case of producing a film-like polyimide, the reaction solution obtained may be applied as it is on a substrate (for example, a glass plate), and the solvent may be removed by evaporation and heat treatment, It becomes possible to produce a film-like polyimide by a simple method. In addition, it does not restrict | limit especially as a coating method of such a reaction liquid, A well-known method (casting method etc.) can be employ | adopted suitably. When the polyamic acid of the present invention is isolated from the reaction solution and used, the isolation method is not particularly limited, and a known method capable of isolating the polyamic acid may be appropriately employed. For example, a method of isolating as a reprecipitate may be employed.

  Further, when the step (II) is performed by employing the method of imidizing by performing the heat treatment, the step (I) and the step (II) may be performed simultaneously as a series of steps. Thus, as a method of simultaneously performing the steps (I) and (II) as a series of steps, for example, a mixture of the tetracarboxylic dianhydride and the aromatic diamine (aromatic diamine in the mixture) and By performing the heating treatment from the step of reacting, the formation of polyamic acid (intermediate) and the subsequent formation of polyimide (imidation) proceed simultaneously, and step (I) and step (II) are simultaneously performed. The method of applying can be adopted.

  In addition, by subjecting the mixture of the tetracarboxylic dianhydride and the aromatic diamine (aromatic diamine in the mixture) to the reaction in this way, heating is performed, so that the steps (I) and (II) are performed. In the presence of a polymerization solvent, the tetracarboxylic dianhydride represented by the general formula (5A) is reacted with the mixture of the aromatic diamines (the aromatic diamine in the mixture). Using a reaction accelerator from the stage, in the presence of the polymerization solvent and the reaction accelerator, the tetracarboxylic dianhydride represented by the general formula (5A) and the mixture of the aromatic diamine are heated and reacted. Thus, it is preferable to form polyimide. Thus, when performing process (I) and process (II) simultaneously, the production | generation of the polyamic acid in process (I) and imidation of the polyamic acid in process (II) are caused continuously by heating. In this case, polyimide is prepared in a solvent. At that time, by using the reaction accelerator, the reaction rate of polyamic acid and imidization can be greatly increased, and the molecular weight can be increased. It becomes. In the case where the step (I) and the step (II) are simultaneously performed by heating using the reaction accelerator, the reaction between the tetracarboxylic dianhydride and the aromatic diamine proceeds by heating. Since water generated by the reaction can be removed by evaporation, the reaction can be efficiently advanced without using a so-called condensing agent (dehydration condensing agent).

  Moreover, in the presence of the polymerization solvent and the reaction accelerator, a polyimide is formed by heating and reacting the mixture of the tetracarboxylic dianhydride represented by the general formula (5A) and the aromatic diamine. In the case (when the step (I) and the step (II) are simultaneously performed by heating using a reaction accelerator), the temperature condition during the heating is preferably 100 to 250 ° C., and preferably 120 to 250 More preferably, it is 150 degreeC, and it is still more preferable that it is 150-220 degreeC. If the temperature condition is less than the lower limit, the reaction temperature is lower than the boiling point of water, so water does not evaporate, the presence of water hinders the progress of the reaction, and the molecular weight of the polyimide is increased. On the other hand, if the upper limit is exceeded, side reactions such as thermal decomposition of the solvent occur, and the amount of impurities in the mixed liquid (varnish) of the polyimide and organic solvent obtained after heating increases. When a film is formed using this, the physical properties of the resulting polyimide film tend to deteriorate.

  Moreover, when performing process (I) and process (II) simultaneously by heating using a reaction accelerator, as a reaction accelerator utilized for the process, triethylamine, diisopropylethylamine, N-methylpiperidine, pyridine, Collidine, lutidine, 2-hydroxypyridine, 4-dimethylaminopyridine (DMAP), 1,4-diazabicyclo [2.2.2] octane (DABCO), diazabicyclononene (DBN), diazabicycloundecene (DBU) In particular, from the viewpoint of reactivity, availability, and practicality, triethylamine, diisopropylethylamine, N-methylpiperidine, and pyridine are preferable, and triethylamine, pyridine, and N-methylpiperidine are more preferable, and triethylamine is preferable. N-methyl pipette Jin is more preferable. Such reaction accelerators may be used alone or in combination of two or more. Moreover, when performing process (I) and process (II) simultaneously by heating using a reaction accelerator, the usage-amount of the reaction accelerator is the tetracarboxylic acid dicarboxylic acid represented by the said General formula (5A). It is preferable to set it as 0.01-10 mass parts with respect to 100 mass parts of total amount (total amount) of the mixture of an anhydride and the said aromatic diamine, and it is more preferable to set it as 0.05-2 mass parts.

The polyimide thus obtained contains two or more repeating units represented by the above general formula (1), wherein X is a group represented by the above general formula (I-1), and At least one of the two or more types of repeating units is a polyimide in which R ¹⁰ in the formula (1) is a repeating unit (A) that is a group represented by the general formula (2). In addition, such a polyimide is the same as what was demonstrated as the polyimide of the said invention (The suitable thing is also the same). Therefore, the manufacturing method of the polyimide of this invention can be utilized suitably as a method for manufacturing the polyimide of the above-mentioned this invention.

  As mentioned above, although the manufacturing method of the polyimide of this invention at the time of using the compound (tetracarboxylic dianhydride) represented by the said general formula (5A) was demonstrated based on suitable embodiment, The production method is not limited to the above method (the method including the above-described step (I) and step (II) is hereinafter simply referred to as “method (A)” in some cases).

As other embodiment of the manufacturing method of the polyimide of this invention, for example, instead of the tetracarboxylic dianhydride represented by the above general formula (5A), the tetra represented by the above general formula (5B) is used. A method of obtaining polyimide in the same manner as the above-described method (A) except that carboxylic dianhydride is used (hereinafter, simply referred to as “method (B)” in some cases) can be employed. In such a method (B), the structure of the polyamic acid obtained in the step corresponding to the step (I) is derived from the compound represented by the general formula (5B). Here, regarding the compound (tetracarboxylic dianhydride) represented by the general formula (5B) used in the method (B), A and R ⁵ in the formula (5B) are each the above general formula (I-2). It is synonymous with A and R ^{5 in the} inside (the suitable thing is also synonymous). Moreover, the manufacturing method of the compound (tetracarboxylic dianhydride) represented by the general formula (5B) used in such a method (B) is not particularly limited, and a known method (for example, International Publication No. 2015/2015) 163314) can be employed as appropriate. The polyamic acid formed in the method (B) is represented by the following general formula (11B):

Wherein (11B), A, ^{R 5} have the same meanings respectively above general formula (I-2) in A, and ^{R 5,} R of ^{R 10} in the formula (11B) is the general formula (1) Is synonymous with ¹⁰ . ]
A group in which R ¹⁰ in the formula (11B) is a group represented by the above general formula (2), containing at least two types of repeating units represented by formula (11). Is a polyamic acid which is a repeating unit (A ″). In addition, polyamic acid in such a method (B) and suitable conditions for each step (polyamide acid viscosity conditions, amount of tetracarboxylic dianhydride used, mixture of tetracarboxylic dianhydride and aromatic diamine Suitable conditions such as reaction conditions are the same as those described in the method (A). Here, the polyamic acid obtained by the method (B) is a repeating unit derived from the mixture of the compound represented by the general formula (5B) and the aromatic diamine (the repeating unit represented by the general formula (11B)). Other than the unit, suitable conditions for R ¹⁰ are the same as those described in the method (A). Thus, in the polyamic acid containing two or more repeating units represented by the general formula (11B), the repeating unit represented by the general formula (11B) other than the repeating unit (A ″) is ( The repeating unit represented by formula (11B) used in combination with the repeating unit (A ″) is not particularly limited, and R ¹⁰ is an arylene group having 6 to 40 carbon atoms, and The repeating unit represented by the general formula (11B) which is other than the group represented by the general formula (2) can be used as appropriate, and among them, the repeating unit other than the repeating unit (A ″). Is preferably a repeating unit (B ″) in which R ¹⁰ in the formula (11B) is any one of the groups represented by the general formulas (3) to (4). A repeating unit (B ″) represented by the general formula (11B) and in which R ¹⁰ is any one of the groups represented by the general formulas (3) to (4), When used in combination with the repeating unit (A ″), the polyimide film is superior in terms of the balance between high heat resistance, colorless transparency, and high hardness when induced into a polyimide film using polyamic acid. Can be obtained. Moreover, according to such a method (B), the polyimide obtained has two types of repeating units represented by the above general formula (1) in which X is a group represented by the above general formula (I-2). In addition, at least one of the two or more repeating units is a repeating unit (A) in which R ¹⁰ in the formula (1) is a group represented by the general formula (2). It becomes polyimide.

  In addition, in the above-mentioned method (A) and method (B), although the compound represented by the said general formula (5A) or (5B) is used as tetracarboxylic dianhydride, manufacture of the polyimide of this invention In the method, as the tetracarboxylic dianhydride, at least one selected from the compound represented by the general formula (5A) and the compound represented by the general formula (5B) can be used. A mixture of the compound represented by the general formula (5A) and the compound represented by the general formula (5B) may be used. Even in such a case, instead of the tetracarboxylic dianhydride represented by the general formula (5A), the compound represented by the general formula (5A) and the compound represented by the general formula (5B) A polyimide can be obtained by adopting the same method (preferable conditions are the same) as the method including the steps (I) and (II) described above except that the mixture is used. When a mixture of the compound represented by the general formula (5A) and the compound represented by the general formula (5B) is used, the repeating unit of the polyamic acid is represented by the general formula (11A). In the polyimide finally obtained, X represented by the general formula (1) and X in the formula is represented by the formula (I) -1) and a repeating unit represented by the general formula (1), and X in the formula is a group represented by the formula (I-2). .

  Furthermore, in the method for producing a polyimide of the present invention, in the presence of the polymerization solvent and the reaction accelerator, at least the compound represented by the general formula (5A) and the compound represented by the general formula (5B) are included. It is preferable to employ a method of forming polyimide by heating and reacting one kind of tetracarboxylic dianhydride and the mixture of the aromatic diamine. According to such a method, the formation of the polyamic acid (intermediate) and the subsequent formation (imidation) of the polyimide can proceed almost simultaneously, whereby the polyimide can be prepared more efficiently. Moreover, the temperature conditions at the time of heating in such a method, the kind of reaction accelerator, the amount of use thereof, and the like are simultaneously applied to the steps (I) and (II) by heating using the above-described reaction accelerator. It is preferable to use conditions similar to those described in the case.

  Moreover, the method which can be suitably employ | adopted in order to manufacture the polyimide of this invention is not limited to the manufacturing method of the polyimide of the above-mentioned this invention. As a method that can be suitably employed for producing the polyimide of the present invention, for example, as a polyimide precursor, the following general formula (101):

Wherein ^{(101), R 1, R} 2, R 3, R 10, n , respectively, have the same meanings as ^{R 1, R 2, R 3} , R 10, n in the above formula (11A), ^{Y 1} , Y ² each independently represents one selected from the group consisting of a hydrogen atom, an alkyl group having 1 to 6 carbon atoms and an alkylsilyl group having 3 to 9 carbon atoms. ]
A group in which R ¹⁰ in the formula (101) is a group represented by the above general formula (2), containing at least two types of repeating units represented by the formula: A resin (A) which is a repeating unit (A ′);
The following general formula (102):

Wherein ^{(102), A, R 5} , R 10 has the same meaning as ^A, R ^{5, R 10} in the general formula ^{(11B), Y 1, Y} 2 are each independently a hydrogen atom, C 1 -C 1 type selected from the group which consists of a C6 alkyl group and a C3-C9 alkylsilyl group is shown. ]
A group in which R ¹⁰ in the formula (102) is a group represented by the above general formula (2), containing at least two types of repeating units represented by the formula: A resin (B) which is a repeating unit (A ″);
And the like, and then imidizing it can also be employed (in this method, for example, when Y ¹ and Y ² in the above formula are both hydrogen atoms, the polyimide of the present invention can be used). This method is the same as the preferred embodiment of the production method (the above-described method (A) and method (B)), and a part of the method can be the same as the method for producing the polyimide of the present invention. The aforementioned polyimide precursor may include both the repeating unit represented by the general formula (101) and the repeating unit represented by the general formula (102).

In such resins (A) and (B), Y ¹ and Y ² in the formula are each independently a hydrogen atom, an alkyl group having 1 to 6 carbon atoms (preferably having 1 to 3 carbon atoms), or a carbon number. It is any one of 3 to 9 alkylsilyl groups. Y ¹ and Y ² can change the type of the substituent and the introduction rate of the substituent by appropriately changing the production conditions. When such Y ¹ and Y ² are both hydrogen atoms, the resins (A) and (B) are both polyamic acids, and when this is used, it is easier to produce polyimide. Tend to be.

Further, in such a resin (A) and (B), if ^Y 1, ^{Y 2} in the formula is 1 to 6 carbon atoms (preferably 1 to 3 carbon atoms) alkyl group, storage of the polyimide precursor It tends to be more stable. ^Further, Y 1, if ^{Y 2} represents an alkyl group having 1 to 6 carbon atoms (preferably 1 to 3 carbon ^atoms), and more preferably Y 1, ^{Y 2} is a methyl group or an ethyl group.

Moreover, in such resin (A) and (B), when Y < ¹ >, Y < ² > in a formula is a C3-C9 alkylsilyl group, the solubility of a polyimide precursor will become more excellent. There is a tendency. Thus, when Y < ¹ >, Y < ² > is a C3-C9 alkylsilyl group, it is more preferable that Y < ¹ >, Y < ² > is a trimethylsilyl group or a t-butyldimethylsilyl group.

In such resins (A) and (B), with respect to Y ¹ and Y ² in the formula, the introduction rate of groups other than hydrogen atoms (alkyl groups and / or alkylsilyl groups) is not particularly limited, but Y ¹ When at least a part of Y ² is an alkyl group and / or an alkylsilyl group, 25% or more (more preferably 50% or more, more preferably 75% or more) of the total amount of Y ¹ and Y ² is an alkyl group. And / or an alkylsilyl group (in this case, Y ¹ and Y ² other than the alkyl group and / or the alkylsilyl group are hydrogen atoms). By making 25% or more of the total amount of Y ¹ and Y ² an alkyl group and / or an alkylsilyl group, the storage stability of the polyimide precursor tends to be more excellent.

Such a resin (A) or the polyimide precursor consisting of ^(B), depending on the type of Y 1, ^{Y 2,} 1) is ^Y 1, ^{Y 2} of the polyamic acid (in the general formula of the repeating units 2) Polyamic acid ester (Y ¹ , Y ² is at least partly an alkyl group); 3) Polyamic acid silyl ester (Y ¹ , Y ² is at least part of an alkylsilyl group); it can. Hereinafter, a method for producing a polyimide precursor will be briefly described for each of the above classifications. In addition, the method for manufacturing such a polyimide precursor is not limited to the following manufacturing methods.

1) Polyamic acid As a method that can be suitably used for producing such a polyamic acid, the step (I) described in the method for producing a polyimide of the present invention or the method (B) described above can be used. It is preferable to employ a process for producing a polyamic acid.

2) Polyamic acid ester Next, the method which can be utilized suitably in order to manufacture the said polyamic acid ester is demonstrated. That is, first, at least one tetracarboxylic dianhydride of the tetracarboxylic dianhydrides represented by the general formulas (5A) and (5B) is reacted with an arbitrary alcohol to obtain a diester dicarboxylic acid. Then, it is reacted with a chlorinating reagent (for example, thionyl chloride, oxalyl chloride, etc.) to obtain diester dicarboxylic acid chloride (tetracarboxylic acid derivative). A monomer component containing the diester dicarboxylic acid chloride thus obtained (at least one tetracarboxylic dianhydride of the tetracarboxylic dianhydrides represented by the general formulas (5A) and (5B)). A component containing the diester dicarboxylic acid chloride derived from an anhydride and, optionally, at least one of the tetracarboxylic dianhydrides represented by the general formulas (5A) and (5B)), and the fragrance A mixture of a group diamine is reacted with stirring in a range of -20 to 120 ° C (more preferably -5 to 80 ° C) for 1 to 72 hours, whereby at least a part of Y ¹ and Y ² is an alkyl group. Polyamic acid ester which is resin (A) or resin (B) containing a repeating unit is obtained. When the reaction is carried out at a temperature of 80 ° C. or higher during stirring, the molecular weight tends to fluctuate depending on the temperature history at the time of polymerization, and imidation may proceed due to heat. Tends to be difficult to produce stably. Moreover, the polyimide precursor which consists of the said polyamic acid ester is simply obtained also by carrying out the dehydration condensation of the diester dicarboxylic acid and the said aromatic diamine using a phosphorus-type condensing agent, a carbodiimide condensing agent, etc. Since the polyimide precursor comprising a polyamic acid ester obtained by such a method is stable, it can be purified by reprecipitation by adding a solvent such as water or alcohol.

3) Polyamic acid silyl ester Hereinafter, methods that can be suitably used for producing the polyamic acid silyl ester will be briefly described by dividing them into so-called indirect methods and direct methods.

<Indirect method>
The following method (indirect method) can be adopted as a method that can be suitably used for producing the polyamic acid silyl ester. That is, first, a mixture of the aromatic diamine and a silylating agent are reacted to obtain the silylated aromatic diamine. In addition, you may refine | purify the aromatic diamine silylated by distillation etc. as needed. Next, a mixture of a silylated aromatic diamine or a mixture of a silylated aromatic diamine and an aromatic diamine (not silylated) is dissolved in a dehydrated solvent. Obtain a solution. Next, while stirring the solution, the tetracarboxylic dianhydride component (at least one of the tetracarboxylic dianhydrides represented by the general formulas (5A) and (5B)) is added to the solution. By gradually adding and stirring for ¹ to 72 hours in the range of 0 to 120 ° C. (preferably 5 to 80 ° C.), a resin containing a repeating unit in which at least part of Y ¹ and Y ² is an alkylsilyl group ( The polyimide precursor which consists of a polyamic-acid silyl ester which is A) or resin (B) can be obtained. In addition, when the reaction at such a stirring temperature is 80 ° C. or higher, the molecular weight is likely to vary depending on the temperature history at the time of polymerization, and imidization may proceed due to heat, It tends to be difficult to stably produce a polyimide precursor.

  In addition, it is preferable to use the silylating agent which does not contain a chlorine atom as said silylating agent. By using a silylating agent that does not contain a chlorine atom in this way, it is not necessary to purify the silylated aromatic diamine, so that the process can be further simplified. Examples of such a silylating agent not containing a chlorine atom include N, O-bis (trimethylsilyl) trifluoroacetamide, N, O-bis (trimethylsilyl) acetamide, and hexamethyldisilazane. The silylating agent is particularly preferably N, O-bis (trimethylsilyl) acetamide or hexamethyldisilazane because it does not contain a fluorine atom and is low in cost.

  In addition, an amine catalyst such as pyridine, piperidine or triethylamine can be used in the silylation reaction of the aromatic diamine in order to accelerate the reaction. Such an amine catalyst can be used as it is as a polymerization catalyst for the polyimide precursor.

<Direct method>
First, the method that can be suitably used for producing the polyamic acid described in the section of “1) Polyamic acid” described above is carried out, and the reaction solution obtained after the reaction is directly prepared as a polyamic acid solution. . Thereafter, a silylating agent is mixed with the obtained polyamic acid solution and stirred for 1 to 72 hours in the range of 0 to 120 ° C. (preferably 5 to 80 ° C.), whereby the polyimide comprising the polyamic acid silyl ester is prepared. A precursor resin can be obtained (direct method). When the reaction is carried out at a temperature of 80 ° C. or higher during stirring, the molecular weight tends to fluctuate depending on the temperature history at the time of polymerization, and imidation may proceed due to heat. Tends to be difficult to produce stably. As a silylating agent that can be used in such a direct method, a silylated polyamic acid or a silylating agent that does not contain a chlorine atom can be used because it is not necessary to purify the obtained polyimide. preferable. Examples of such a silylating agent not containing a chlorine atom include N, O-bis (trimethylsilyl) trifluoroacetamide, N, O-bis (trimethylsilyl) acetamide, and hexamethyldisilazane. Further, as such a silylating agent, N, O-bis (trimethylsilyl) acetamide and hexamethyldisilazane are particularly preferable because they do not contain a fluorine atom and are low in cost.

As described above, any of the methods for producing the polyimide precursor described above can be carried out in an organic solvent. Thus, when the polyimide precursor in an organic solvent is manufactured, the varnish of a polyimide precursor can be obtained easily. And the polyimide can be easily obtained by apply | coating the varnish obtained in this way on surfaces, such as a board | substrate, and imidating. As such an imidization method, a method capable of preparing a polyimide by forming an imide bond according to the type of polyimide precursor (particularly the type of Y ¹ and Y ^{2 in} the formula) is appropriately adopted. For example, when the polyimide precursor is a polyamic acid, it is preferable to employ a method similar to the method described in the step (II) described in the polyimide manufacturing method of the present invention.

[Polyimide solution]
The polyimide solution of the present invention contains the polyimide of the present invention and an organic solvent. As an organic solvent used for such a polyimide solution, the same solvent as the polymerization solvent described above can be suitably used. In addition, the polyimide solution of the present invention can be used after the reaction when the polyimide obtained by carrying out the above-described method for producing the polyimide of the present invention is sufficiently soluble in the polymerization solvent (organic solvent) used during the production. The obtained reaction solution may be used as a polyimide solution as it is (for example, as an organic solvent (polymerization solvent), by using a material that can sufficiently dissolve the obtained polyimide, and by forming the polyimide in the solvent, after the reaction The obtained reaction liquid can be used as a polyimide solution as it is.)

  Thus, as the organic solvent used in the polyimide solution of the present invention, the same solvents as those described in the above polymerization solvent can be suitably used. In addition, as an organic solvent used for the polyimide solution of the present invention, for example, a halogen-based solvent having a boiling point of 200 ° C. or less (for example, from the viewpoint of transpiration and removability of the solvent when the polyimide solution is used as a coating solution) , Dichloromethane (boiling point 40 ° C), trichloromethane (boiling point 62 ° C), carbon tetrachloride (boiling point 77 ° C), dichloroethane (boiling point 84 ° C), trichloroethylene (boiling point 87 ° C), tetrachloroethylene (boiling point 121 ° C), tetrachloroethane (boiling point) 147 ° C.), chlorobenzene (boiling point 131 ° C.), o-dichlorobenzene (boiling point 180 ° C.), etc.).

  Moreover, as an organic solvent used for such a polyimide solution, N-methyl-2-pyrrolidone, N, N from the viewpoint of solubility, film-forming property, productivity, industrial availability, presence / absence of existing facilities, and price. -Dimethylacetamide, γ-butyrolactone, propylene carbonate, tetramethylurea, 1,3-dimethyl-2-imidazolidinone are preferred, N-methyl-2-pyrrolidone, N, N-dimethylacetamide, γ-butyrolactone, tetramethyl Urea is more preferable, and N, N-dimethylacetamide and γ-butyrolactone are particularly preferable. In addition, you may utilize such an organic solvent individually by 1 type or in combination of 2 or more types.

  Moreover, such a polyimide solution can also be suitably used as a coating solution for producing various processed products. For example, when forming a film, the polyimide solution of the present invention is used as a coating liquid, and this is coated on a substrate to obtain a coating film, and then the solvent is removed to remove the polyimide film. It may be formed. Such a coating method is not particularly limited, and a known method (spin coating method, bar coating method, dip coating method, etc.) can be appropriately used.

  In such a polyimide solution, the content (dissolution amount) of the polyimide is not particularly limited, but is preferably 1 to 75% by mass, and more preferably 10 to 50% by mass. When the content is less than the lower limit, the film thickness after film formation tends to be thin when used for film formation and the like. On the other hand, when the content exceeds the upper limit, a part tends to be insoluble in the solvent. . Furthermore, depending on the purpose of use, such a polyimide solution includes an antioxidant (phenolic, phosphite, thioether, etc.), ultraviolet absorber, hindered amine light stabilizer, nucleating agent, resin additive ( Additives such as fillers, talc, glass fibers, etc.), flame retardants, processability improvers and lubricants may be further added. In addition, it does not restrict | limit especially as these additives, A well-known thing can be utilized suitably, and a commercially available thing may be utilized.

  The polyimide solution of the present invention has been described above. Next, the film of the present invention will be described.

[Polyimide film]
The polyimide film of the present invention is made of the polyimide of the present invention. Thus, the polyimide film of the present invention may be a film made of polyimide described as the polyimide of the present invention.

  The thickness of the polyimide film of the present invention is not particularly limited, but is preferably 1 to 500 μm, and more preferably 10 to 200 μm. If the thickness is less than the lower limit, the strength tends to be reduced and handling tends to be difficult.On the other hand, if the upper limit is exceeded, multiple coatings may be required or processing may be complicated. Tend to occur.

  The form of such a polyimide film is not particularly limited as long as it is in the form of a film, and can be appropriately designed into various shapes (disk shape, cylindrical shape (film processed into a cylindrical shape), etc.) When manufactured using a polyimide solution, the design can be changed more easily.

  The method for preparing such a film of the present invention (polyimide film) is not particularly limited. For example, the reaction solution (polyamic acid solution) obtained by the above step (I) is applied onto a substrate and a solvent is used. A method of preparing a polyimide film by imidization may be adopted after removing the substrate, or a polyimide film is prepared by applying the polyimide solution of the present invention on a substrate and removing the solvent. A method may be adopted.

  Such a polyimide film of the present invention is composed of the polyimide of the present invention, so that it can be sufficiently excellent in transparency and heat resistance, and has sufficiently high hardness. Is also possible. Therefore, such a polyimide film of the present invention includes, for example, a film for a flexible wiring substrate, a film used for a liquid crystal alignment film, a transparent conductive film for organic EL, a film for organic EL lighting, a flexible substrate film, and a substrate for flexible organic EL. Film, flexible transparent conductive film, transparent conductive film, transparent conductive film for organic thin film solar cell, transparent conductive film for dye-sensitized solar cell, flexible gas barrier film, film for touch panel, front film for flexible display, Back film for flexible display, TFT substrate film for flat panel detector, polyimide belt, coating agent, barrier film, sealing material, interlayer insulating material, passivation film, TAB (Tape Auto) ated Bonding) tape, an optical waveguide, a color filter substrate, a semiconductor coating agent, it can be appropriately utilized heat insulating tape, for applications such as wire enamels.

  EXAMPLES Hereinafter, although this invention is demonstrated more concretely based on an Example and a comparative example, this invention is not limited to a following example.

  First, the evaluation method of the characteristics (linear expansion coefficient etc.) of the polyimide which forms the film obtained by each Example and each comparative example is demonstrated.

<Identification of molecular structure>
Identification of the molecular structure of the compound obtained in each example or the like was performed by infrared absorption spectrum measurement (IR measurement). In addition, as a measuring apparatus, IR measuring machine (The JASCO Corporation make, brand name: FT / IR-4100) was used.

<Measurement of total light transmittance, haze (turbidity) and yellowness (YI)>
The total light transmittance value (unit:%), haze (turbidity: HAZE) and yellowness (YI) of the polyimide obtained in each example etc. are used for measuring the film obtained in each example as it is. As a measuring device, the product name “Haze Meter NDH-5000” manufactured by Nippon Denshoku Industries Co., Ltd. or the product name “Spectral Color Meter SD6000” manufactured by Nippon Denshoku Industries Co., Ltd. is used as a measuring device. Was determined by In this measurement, the total light transmittance and haze were measured with a product name “Haze Meter NDH-5000” manufactured by Nippon Denshoku Industries Co., Ltd., and the product name “Spectral Color Meter SD6000 manufactured by Nippon Denshoku Industries Co., Ltd.”. The yellowness was measured. Further, the total light transmittance is obtained by performing measurement in accordance with JIS K7361-1 (issued in 1997), and the haze (turbidity) is obtained by performing measurement in accordance with JIS K7136 (issued in 2000). The yellowness (YI) was determined by performing measurement in accordance with ASTM E313-05 (issued in 2005).

<Measurement of linear expansion coefficient (CTE)>
From the polyimide (film-shaped polyimide) obtained in each example etc., a film having a size of 20 mm in length and 5 mm in width (the thickness of the film does not affect the measured value, so the thickness was produced in each example. The thickness of the film was adopted as it was.) Was formed as a measurement sample, and a thermomechanical analyzer (trade name “TMA8310” manufactured by Rigaku) was used as a measurement device, and a tensile mode (49 mN) in a nitrogen atmosphere. The temperature was increased from room temperature to 200 ° C. (first temperature increase) under the condition of a temperature increase rate of 5 ° C./min, allowed to cool to 30 ° C. or less, and then increased from that temperature to 400 ° C. (2 The temperature is increased for the second time), and the change in the length of the sample in the longitudinal direction at the time of the temperature increase is measured. Next, using the TMA curve obtained by the measurement at the time of the second temperature increase (measurement when the temperature is raised from the temperature at the time of standing to 400 ° C.), 1 in the temperature range of 100 ° C. to 200 ° C. The average value of the change in length per degree C is obtained, and the obtained value is measured as the linear expansion coefficient of polyimide.

<Measurement of 5% weight loss temperature>
The 5% weight loss temperature of the compound obtained in each example, etc., was measured using a thermogravimetric analyzer (“TG / DTA220” manufactured by SII Nanotechnology Co., Ltd.) using the polyimide film produced in each example. The temperature is raised from room temperature to 40 ° C. while flowing nitrogen gas, and the starting temperature is 40 ° C. and 10 ° C./min. The temperature was determined by measuring the temperature at which the weight of the sample used was reduced by 5%.

<Measurement of pencil hardness>
Pencil hardness was measured using the polyimide film obtained in each example. That is, with respect to the polyimide film obtained in each example etc., the hardness of the surface of the polyimide film was measured using a pencil hardness tester (trade name “TQC Pencil Scratch Hardness Tester”) manufactured by Cortemac Co., Ltd. in 1999. It was determined by measuring in accordance with the method specified in JIS K5600-5-4 issued in 1987.

<Measurement of glass transition temperature (Tg)>
The value (unit: ° C.) of the glass transition temperature (Tg) of the polyimide obtained in each example or the like uses a thermomechanical analyzer (trade name “TMA8310” or “TMA8311” manufactured by Rigaku) as a measuring device. Furthermore, a sample having a size of 20 mm in length and 5 mm in width cut out from the polyimide film obtained in each example or the like as a measurement sample (the thickness of the sample does not affect the measured value, and thus was obtained in the example. The TMA curve was obtained by measuring under the tension condition (49 mN) and the heating rate of 5 ° C./min under a nitrogen atmosphere, and the TMA curve was changed due to the glass transition. It calculated | required by extrapolating the curve before and behind that point.

Example 1
<Preparation process of tetracarboxylic dianhydride>
In accordance with the method described in Synthesis Example 1, Example 1 and Example 2 of International Publication No. 2011/099518, the following general formula (12):

Tetracarboxylic dianhydride represented by the formula (norbornane-2-spiro-α-cyclopentanone-α′-spiro-2 ″ -norbornane-5,5 ″, 6,6 ″ -tetracarboxylic acid dianhydride Anhydride: hereinafter referred to as “CpODA” in some cases).

<Polyimide preparation process>
Under a nitrogen atmosphere, in a 50 mL screw tube, 4,4′-diamino-2,2′-dimethylbiphenyl (hereinafter referred to as “m-Tol” in some cases) represented by the above general formula (7) which is an aromatic diamine. 1.06 g (5.00 mmol), an aromatic diamine represented by the following general formula (13):

1.74 g (5.00 mmol) of 9,9-bis (4-aminophenyl) fluorene represented by the formula (hereinafter sometimes referred to as “FDA”) and the above general formula (12) By introducing 3.84 g (10.0 mmol) of tetracarboxylic dianhydride (CpODA), a mixture of two aromatic diamines (m-Tol and FDA) and the tetracarboxylic dianhydride are introduced into the screw tube. (CpODA) was introduced. Next, 15.4 g of dimethylacetamide (N, N-dimethylacetamide) as an organic solvent, 11.1 g of γ-butyrolactone as an organic solvent, and 0.1% of triethylamine as a reaction accelerator are placed in the screw tube. By introducing 051 g (0.50 mmol), the mixture of the two aromatic diamines (m-Tol and FDA), the tetracarboxylic dianhydride (CpODA), and the organic solvent (N, N-dimethylacetamide) And γ-butyrolactone) and a reaction accelerator (triethylamine) were mixed to obtain a mixed solution.

  The mixed liquid thus obtained was stirred for 3 hours under a nitrogen atmosphere at 180 ° C. for 3 hours to obtain a viscous uniform light yellow reaction liquid. Thus, the polyimide derived from the mixture (m-Tol and FDA) of aromatic diamine and the said tetracarboxylic dianhydride (CpODA) was prepared by the heating process, and the reaction liquid (polyimide solution) was obtained. .

<Preparation process of polyimide film>
Next, the reaction solution was spin-coated on a glass plate (length: 75 mm, width 50 mm, thickness 1.3 mm) to form a coating film on the glass plate. Thereafter, the glass plate on which the coating film has been formed is put into an oven, and in a nitrogen atmosphere, first, the temperature condition (first temperature condition) is set at 60 ° C. for 4 hours, and then the temperature condition (first condition) The temperature of the second temperature (firing temperature) is changed to 250 ° C. and left to stand for 1 hour to cure the coating film to obtain a polyimide-coated glass coated with a polyimide thin film (polyimide film) on a glass plate. It was. Next, the polyimide-coated glass thus obtained is immersed in water at 90 ° C. for 0.5 hours, and the polyimide film is recovered by peeling off the polyimide film from the glass substrate. A film (polyimide film) was obtained. The film thickness of the polyimide film thus obtained was 70 μm.

In addition, in order to identify the molecular structure of the compound forming the film thus obtained, an IR spectrum was measured using an IR measuring device (trade name: FT / IR-4100, manufactured by JASCO Corporation). However, since the C═O stretching vibration of imide carbonyl and CpODA was observed at 1700 cm ⁻¹ and 1774 cm ⁻¹ , the C = O stretching vibration of the carbonyl group of CpODA was observed, and the compound constituting the obtained film was polyimide. It was confirmed. Moreover, the evaluation result of the characteristic of the obtained polyimide film is shown in Table 1.

(Comparative Example 1)
A mixture of two kinds of aromatic diamines, m-Tol (4,4′-diamino-2,2′-dimethylbiphenyl) and FDA (9,9-bis (4-aminophenyl) fluorene), is introduced into the screw tube. Instead, by introducing 3.48 g (10.0 mmol) of FDA alone, only FDA is introduced as an aromatic diamine into the screw tube,
The amount of dimethylacetamide (N, N-dimethylacetamide) used was changed from 15.4 g to 16.4 g,
The amount of γ-butyrolactone used was changed from 11.1 g to 12.9 g,
A colorless transparent film (polyimide film) made of polyimide was obtained in the same manner as in Example 1 except that the second temperature condition for curing the coating film was changed from 250 ° C to 300 ° C. The film thickness of the polyimide film thus obtained was 32 μm.

In addition, in order to identify the molecular structure of the compound forming the film thus obtained, an IR spectrum was measured using an IR measuring device (trade name: FT / IR-4100, manufactured by JASCO Corporation). where, C = O stretching vibration of an imide carbonyl and CpODA is ^1702cm -1, since it was observed in 1774 cm ^-1, it is the compound constituting the resulting film is a polyimide was confirmed. Table 1 shows the evaluation results of the properties of the obtained polyimide film.

  As is clear from the results shown in Table 1, the polyimide of the present invention (Example 1) was confirmed to have a sufficiently high level of transparency from the values of total light transmittance, HAZE and YI. Furthermore, it was confirmed that a sufficiently high level of heat resistance was obtained from a 5% weight loss temperature. Moreover, from the comparison of the polyimide obtained in Example 1 (the polyimide of the present invention) and the polyimide obtained in Comparative Example 1, when m-Tol is mixed with aromatic diamine (Example 1). Further, it has been found that the pencil hardness can be further improved. From such a result, according to the polyimide of the present invention (Example 1), it was confirmed that it was possible to make the hardness higher while having sufficiently high transparency and heat resistance.

(Example 2)
1.06 g (5.00 mmol) of 4,4′-diamino-2,2′-dimethylbiphenyl (m-Tol), which is an aromatic diamine, and 9,9-bis (4- Instead of introducing 1.74 g (5.00 mmol) of aminophenyl) fluorene (FDA), 0.707 g (3.33 mmol) of 4,4′-diamino-2,2′-dimethylbiphenyl (m-Tol), The following general formula (14):

By introducing 1.95 g (6.67 mmol) of 1,3-bis (3-aminophenoxy) benzene (hereinafter, sometimes referred to as “APB-N”) represented by the following formula, Introducing a mixture of aromatic diamines (m-Tol and APB-N);
The amount of dimethylacetamide (N, N-dimethylacetamide) used was changed from 15.4 g to 13.1 g,
A colorless transparent film (polyimide film) made of polyimide was obtained in the same manner as in Example 1 except that the amount of γ-butyrolactone used was changed from 11.1 g to 12.9 g. The film thickness of the polyimide film thus obtained was 15 μm.

In addition, in order to identify the molecular structure of the compound forming the film thus obtained, an IR spectrum was measured using an IR measuring device (trade name: FT / IR-4100, manufactured by JASCO Corporation). where, C = O stretching vibration of an imide carbonyl and CpODA is ^{1703 cm} -1, since it was observed in 1774 cm ^-1, it is the compound constituting the resulting film is a polyimide was confirmed. The evaluation results of the properties of the obtained polyimide film are shown in Table 2.

(Comparative Example 2)
Instead of introducing a mixture of two aromatic diamines (m-Tol and APB-N) into the screw tube, 2.92 g (10.0 mmol) of APB-N alone was introduced into the screw tube. As an aromatic diamine, only APB-N is introduced,
The amount of dimethylacetamide (N, N-dimethylacetamide) used was changed from 13.1 g to 1.4 g,
A colorless transparent film (polyimide film) made of polyimide was obtained in the same manner as in Example 2 except that the amount of γ-butyrolactone used was changed from 12.9 g to 11.1 g. The film thickness of the polyimide film thus obtained was 63 μm.

In addition, in order to identify the molecular structure of the compound forming the film thus obtained, an IR spectrum was measured using an IR measuring device (trade name: FT / IR-4100, manufactured by JASCO Corporation). where, C = O stretching vibration of an imide carbonyl and CpODA is ^{1703 cm} -1, since it was observed 1777cm ^-1, it is the compound constituting the resulting film is a polyimide was confirmed. The evaluation results of the properties of the obtained polyimide film are shown in Table 2.

  As is clear from the results shown in Table 2, the polyimide of the present invention (Example 2) was confirmed to have a sufficiently high level of transparency from the values of total light transmittance, HAZE and YI. Furthermore, it was confirmed that a sufficiently high level of heat resistance was obtained from a 5% weight loss temperature. Moreover, from the contrast of the polyimide obtained in Example 2 (the polyimide of the present invention) and the polyimide obtained in Comparative Example 2, when m-Tol is mixed with aromatic diamine (Example 2). Further, it has been found that the pencil hardness can be further improved. From such a result, according to the polyimide (Example 2) of the present invention, it was confirmed that it was possible to make the hardness higher while having sufficiently high transparency and heat resistance.

(Example 3)
1.06 g (5.00 mmol) of 4,4′-diamino-2,2′-dimethylbiphenyl (m-Tol), which is an aromatic diamine, and 9,9-bis (4- Instead of introducing 1.74 g (5.00 mmol) of aminophenyl) fluorene (FDA), 0.707 g (3.33 mmol) of 4,4′-diamino-2,2′-dimethylbiphenyl (m-Tol), The following general formula (15):

By introducing 2.88 g (6.67 mmol) of bis [4- (3-aminophenoxy) phenyl] sulfone (hereinafter sometimes referred to as “BAPS-M”) represented by A mixture of aromatic diamines (m-Tol and BAPS-M),
A colorless transparent film (polyimide film) made of polyimide was obtained in the same manner as in Example 1 except that the amount of dimethylacetamide (N, N-dimethylacetamide) used was changed from 15.4 g to 18.5 g. The film thickness of the polyimide film thus obtained was 22 μm.

In addition, in order to identify the molecular structure of the compound forming the film thus obtained, an IR spectrum was measured using an IR measuring device (trade name: FT / IR-4100, manufactured by JASCO Corporation). where, C = O stretching vibration of an imide carbonyl and CpODA is ^1702cm -1, since it was observed in 1776 cm ^-1, it is the compound constituting the resulting film is a polyimide was confirmed. Table 3 shows the evaluation results of the properties of the obtained polyimide film.

(Comparative Example 3)
Instead of introducing a mixture of two kinds of aromatic diamines (m-Tol and BAPS-M) into the screw tube, 4.32 g (10.0 mmol) of BAPS-M was introduced alone, thereby In addition, only BAPS-M is introduced as an aromatic diamine,
A colorless transparent film (polyimide film) made of polyimide was obtained in the same manner as in Example 3 except that the amount of dimethylacetamide (N, N-dimethylacetamide) used was changed from 18.5 g to 3.9 g. The film thickness of the polyimide film thus obtained was 50 μm.

In addition, in order to identify the molecular structure of the compound forming the film thus obtained, an IR spectrum was measured using an IR measuring device (trade name: FT / IR-4100, manufactured by JASCO Corporation). where, C = O stretching vibration of an imide carbonyl and CpODA is ^{1704 cm} -1, since it was observed in 1776 cm ^-1, it is the compound constituting the resulting film is a polyimide was confirmed. Table 3 shows the evaluation results of the properties of the obtained polyimide film.

  As is clear from the results shown in Table 3, the polyimide of the present invention (Example 3) was confirmed to have a sufficiently high level of transparency from the values of total light transmittance, HAZE and YI. Furthermore, it was confirmed that a sufficiently high level of heat resistance was obtained from a 5% weight loss temperature. Moreover, from the contrast of the polyimide obtained in Example 3 (polyimide of the present invention) and the polyimide obtained in Comparative Example 3, when m-Tol is mixed with aromatic diamine (Example 3). Further, it has been found that the pencil hardness can be further improved. From these results, it was confirmed that according to the polyimide of the present invention (Example 3), it was possible to make the hardness higher while having sufficiently high transparency and heat resistance.

Example 4
1.06 g (5.00 mmol) of 4,4′-diamino-2,2′-dimethylbiphenyl (m-Tol), which is an aromatic diamine, and 9,9-bis (4- Instead of introducing 1.74 g (5.00 mmol) of aminophenyl) fluorene (FDA), 0.705 g (3.33 mmol) of 4,4′-diamino-2,2′-dimethylbiphenyl (m-Tol), The following general formula (16):

By introducing 2.88 g (6.67 mmol) of bis [4- (4-aminophenoxy) phenyl] sulfone (hereinafter sometimes referred to as “BAPS”) represented by the following formula, A mixture of group diamines (m-Tol and BAPS),
A colorless transparent film (polyimide film) made of polyimide was obtained in the same manner as in Example 1 except that the amount of dimethylacetamide (N, N-dimethylacetamide) used was changed from 15.4 g to 18.5 g. The film thickness of the polyimide film thus obtained was 45 μm.

In addition, in order to identify the molecular structure of the compound forming the film thus obtained, an IR spectrum was measured using an IR measuring device (trade name: FT / IR-4100, manufactured by JASCO Corporation). where, C = O stretching vibration of an imide carbonyl and CpODA is ^{1700 cm} -1, since it was observed in 1774 cm ^-1, it is the compound constituting the resulting film is a polyimide was confirmed. Table 4 shows the evaluation results of the properties of the obtained polyimide film.

(Comparative Example 4)
Instead of introducing a mixture of two aromatic diamines (m-Tol and BAPS) into the screw tube, 4.32 g (10.0 mmol) of BAPS alone was introduced, and as an aromatic diamine in the screw tube. Introduced only BAPS, and
A colorless transparent film (polyimide film) made of polyimide was obtained in the same manner as in Example 4 except that the amount of dimethylacetamide (N, N-dimethylacetamide) was changed from 18.5 g to 21.5 g. The film thickness of the polyimide film thus obtained was 31 μm.

In addition, in order to identify the molecular structure of the compound forming the film thus obtained, an IR spectrum was measured using an IR measuring device (trade name: FT / IR-4100, manufactured by JASCO Corporation). where, C = O stretching vibration of an imide carbonyl and CpODA is ^1702cm -1, since it was observed in 1774 cm ^-1, it is the compound constituting the resulting film is a polyimide was confirmed. Table 4 shows the evaluation results of the properties of the obtained polyimide film.

  As is apparent from the results shown in Table 4, the polyimide of the present invention (Example 4) was confirmed to have a sufficiently high level of transparency from the values of total light transmittance and HAZE, and It was confirmed to have a sufficiently high level of heat resistance from the 5% weight loss temperature. Moreover, from the contrast of the polyimide obtained in Example 4 (polyimide of the present invention) and the polyimide obtained in Comparative Example 4, when m-Tol is mixed with an aromatic diamine (Example 4). Further, it has been found that the pencil hardness can be further improved. From such a result, according to the polyimide of the present invention (Example 4), it was confirmed that it was possible to make the hardness higher while having sufficiently high transparency and heat resistance.

(Example 5)
<Preparation process of tetracarboxylic dianhydride>
In accordance with the method described in Example 1 of WO2015 / 163314, the following general formula (111):

A tetracarboxylic dianhydride represented by the formula (hereinafter sometimes referred to as “BzDA”) was prepared.

<Polyimide preparation process>
Under a nitrogen atmosphere, 0.84 g of 4,4′-diamino-2,2′-dimethylbiphenyl (m-Tol) represented by the above general formula (7), which is an aromatic diamine, in a 50 mL screw tube ( 3.96 mmol), 0.74 g (3.96 mmol) of 4,4′-diaminodiphenyl ether (hereinafter sometimes referred to as “DDE”), which is an aromatic diamine, and the above general formula (111) By introducing 3.25 g (8.00 mmol) of tetracarboxylic dianhydride (BzDA), a mixture of two aromatic diamines (m-Tol and DDE) and the tetracarboxylic dianhydride are introduced into the screw tube. (BzDA) was introduced. Next, 11.1 g of dimethylacetamide (N, N-dimethylacetamide) as an organic solvent, 8.4 g of γ-butyrolactone as an organic solvent, and 0.03 of triethylamine as a reaction accelerator are placed in the screw tube. By introducing 040 g (0.40 mmol), the mixture of the two aromatic diamines (m-Tol and DDE), the tetracarboxylic dianhydride (BzDA), and the organic solvent (N, N-dimethylacetamide) And γ-butyrolactone) and a reaction accelerator (triethylamine) were mixed to obtain a mixed solution.

  The mixed liquid thus obtained was stirred for 6 hours under a nitrogen atmosphere at a temperature of 180 ° C. for 6 hours to obtain a viscous uniform light yellow reaction liquid. Thus, a polyimide derived from a mixture of aromatic diamines (m-Tol and DDE) and the tetracarboxylic dianhydride (BzDA) was prepared by a heating step, and a reaction solution (polyimide solution: charging raw materials). The polyimide concentration determined from the amount was 20% by mass).

<Preparation process of polyimide film>
Next, the reaction solution was spin-coated on a glass plate (length: 75 mm, width 50 mm, thickness 1.3 mm) to form a coating film on the glass plate. Thereafter, the glass plate on which the coating film has been formed is put into an oven, and in a nitrogen atmosphere, first, the temperature condition (first temperature condition) is set at 60 ° C. for 4 hours, and then the temperature condition (first condition) The temperature of the second temperature (firing temperature) is changed to 250 ° C. and left to stand for 1 hour to cure the coating film to obtain a polyimide-coated glass coated with a polyimide thin film (polyimide film) on a glass plate. It was. Next, the polyimide-coated glass thus obtained is immersed in water at 90 ° C. for 0.5 hours, and the polyimide film is recovered by peeling off the polyimide film from the glass substrate. A film (polyimide film) was obtained. The film thickness of the polyimide film thus obtained was 60 μm.

In addition, in order to identify the molecular structure of the compound forming the film thus obtained, an IR spectrum was measured using an IR measuring device (trade name: FT / IR-4100, manufactured by JASCO Corporation). However, since the C═O stretching vibration of imidecarbonyl was observed at 1704 cm ⁻¹ and 1776 cm ⁻¹ , it was confirmed that the compound constituting the obtained film was polyimide. Table 5 shows the evaluation results of the properties of the obtained polyimide film.

(Comparative Example 5)
Instead of introducing a mixture of two aromatic diamines (m-Tol and DDE) into the screw tube, 1.98 g (9.9 mmol) of DDE alone was introduced into the screw tube as an aromatic diamine. Introduced only DDE, and changed the amount of tetracarboxylic dianhydride (BzDA) represented by the above general formula (111) from 3.25 g to 4.06 g (10.0 mmol), and dimethylacetamide (N , N-dimethylacetamide) was changed from 11.1 g to 13.7 g, γ-butyrolactone was used from 8.4 g to 10.4 g, and triethylamine was used from 0.040 g. A colorless transparent film made of polyimide (polyimid) as in Example 5 except that the amount was changed to 0.051 g (0.50 mmol). Film) was obtained. The film thickness of the polyimide film thus obtained was 5 μm.

In addition, in order to identify the molecular structure of the compound forming the film thus obtained, an IR spectrum was measured using an IR measuring device (trade name: FT / IR-4100, manufactured by JASCO Corporation). However, since the C═O stretching vibration of imidecarbonyl was observed at 1704 cm ⁻¹ and 1774 cm ⁻¹ , it was confirmed that the compound constituting the obtained film was polyimide. Table 5 shows the evaluation results of the properties of the obtained polyimide film.

  As is clear from the results shown in Table 5, the polyimide of the present invention (Example 5) was confirmed to have a sufficiently high level of transparency from the values of total light transmittance and HAZE. It was confirmed to have a sufficiently high level of heat resistance from the 5% weight loss temperature. Moreover, from the contrast of the polyimide obtained in Example 5 (the polyimide of the present invention) and the polyimide obtained in Comparative Example 5, when m-Tol is mixed with an aromatic diamine (Example 5). Further, it has been found that the pencil hardness can be further improved. From these results, it was confirmed that according to the polyimide of the present invention (Example 5), it was possible to make the hardness higher while having sufficiently high transparency and heat resistance.

(Example 6)
In the screw tube, 0.84 g (3.96 mmol) of 4,4′-diamino-2,2′-dimethylbiphenyl (m-Tol), which is an aromatic diamine, and 4,4′-diamino, which is an aromatic diamine. Instead of introducing 0.79 g (3.96 mmol) of diphenyl ether (DDE), 1.05 g (4.95 mmol) of 4,4′-diamino-2,2′-dimethylbiphenyl (m-Tol), aromatic diamine By introducing 1.12 g (4.95 mmol) of 4,4′-diaminobenzanilide (Seika Co., Ltd. (former name: Wakayama Seika Co., Ltd.): hereinafter sometimes referred to as “DABAN”) A mixture of two aromatic diamines (m-Tol and DABAN) is introduced into the screw tube, and the tetracarboxylic acid dicarboxylic acid represented by the above general formula (111) is introduced. The amount of water (BzDA) charged was changed from 3.25 g to 4.06 g (10.0 mmol), the amount of dimethylacetamide (N, N-dimethylacetamide) used was changed from 11.1 g to 8.3 g, Except that the amount of γ-butyrolactone used was changed from 8.4 g to 6.3 g and the amount of triethylamine used was changed from 0.040 g to 0.025 g (0.25 mmol), the same as in Example 5. A colorless transparent film (polyimide film) made of polyimide was obtained. The film thickness of the polyimide film thus obtained was 50 μm.

In addition, in order to identify the molecular structure of the compound forming the film thus obtained, an IR spectrum was measured using an IR measuring device (trade name: FT / IR-4100, manufactured by JASCO Corporation). However, since the C═O stretching vibration of imidecarbonyl was observed at 1703 cm ⁻¹ and 1773 cm ⁻¹ , it was confirmed that the compound constituting the obtained film was polyimide. Table 6 shows the evaluation results of the properties of the obtained polyimide film.

(Comparative Example 6)
Instead of introducing a mixture of two aromatic diamines (m-Tol and DABAN) into the screw tube, 2.70 g (11.9 mmol) of DABAN alone was introduced into the screw tube as an aromatic diamine. Introduced only DABAN, and changed the amount of tetracarboxylic dianhydride (BzDA) represented by the above general formula (111) from 4.06 g to 4.88 g (12.0 mmol), and dimethylacetamide (N , N-dimethylacetamide) was changed from 11.1 g to 10.1 g, γ-butyrolactone was changed from 6.3 g to 7.6 g, and triethylamine was used from 0.025 g. A colorless transparent film made of polyimide in the same manner as in Example 6 except that the amount was changed to 0.061 g (0.50 mmol). Was obtained (polyimide film). The film thickness of the polyimide film thus obtained was 42 μm.

In addition, in order to identify the molecular structure of the compound forming the film thus obtained, an IR spectrum was measured using an IR measuring device (trade name: FT / IR-4100, manufactured by JASCO Corporation). However, since the C═O stretching vibration of imidecarbonyl was observed at 1701 cm ⁻¹ and 1772 cm ⁻¹ , it was confirmed that the compound constituting the obtained film was polyimide. Table 6 shows the evaluation results of the properties of the obtained polyimide film.

  As is clear from the results shown in Table 6, it was confirmed that the polyimide of the present invention (Example 6) has a sufficiently high level of transparency from the values of total light transmittance and HAZE, and It was confirmed to have a sufficiently high level of heat resistance from the 5% weight loss temperature. Moreover, from the comparison of the polyimide obtained in Example 6 (the polyimide of the present invention) and the polyimide obtained in Comparative Example 6, when m-Tol is mixed with aromatic diamine (Example 6). Further, it has been found that the pencil hardness can be further improved. From such a result, according to the polyimide of the present invention (Example 6), it was confirmed that it was possible to make the hardness higher while having sufficiently high transparency and heat resistance.

(Example 7)
In the screw tube, 0.84 g (3.96 mmol) of 4,4′-diamino-2,2′-dimethylbiphenyl (m-Tol) represented by the general formula (7) which is an aromatic diamine and 4 Instead of introducing a mixture of 0.79 g (3.96 mmol) of 4,4'-diaminodiphenyl ether (DDE) with 2.10 g (9.90 mmol) of m-Tol and 1.98 g (9.90 mmol) of DDE. ), And instead of introducing 3.25 g (8.00 mmol) of tetracarboxylic dianhydride (BzDA) represented by the following general formula (111), 4.06 g (10.0 mmol) of BzDA And 1,2,4,5-cyclohexanetetracarboxylic dianhydride (Tokyo Chemical Industry Co., Ltd .: hereinafter referred to as “HPMDA”) 2.24 g (10.0 mmo) ), The amount of dimethylacetamide (N, N-dimethylacetamide) used was changed from 11.1 g to 23.7 g, the amount of γ-butyrolactone was changed from 8.4 g to 17.9 g, A colorless transparent film (polyimide film) made of polyimide was obtained in the same manner as in Example 5 except that the amount of triethylamine used was changed from 0.040 g (0.40 mmol) to 0.051 g (0.50 mmol). The film thickness of the polyimide film thus obtained was 20 μm.

In addition, in order to identify the molecular structure of the compound forming the film thus obtained, an IR spectrum was measured using an IR measuring device (trade name: FT / IR-4100, manufactured by JASCO Corporation). However, since the C═O stretching vibration of imidecarbonyl was observed at 1704 cm ⁻¹ and 1774 cm ⁻¹ , it was confirmed that the compound constituting the obtained film was polyimide. Table 7 shows the evaluation results of the properties of the obtained polyimide film.

(Comparative Example 7)
Instead of introducing a mixture of two aromatic diamines (m-Tol and DDE) into the screw tube, 1.59 g (7.92 mmol) of DDE alone was introduced into the screw tube as an aromatic diamine. Introduced only DDE and changed the amount of tetracarboxylic dianhydride (BzDA) represented by the following general formula (111) from 4.06 g (10.0 mmol) to 1.63 g (4.00 mmol). The amount of 1,2,4,5-cyclohexanetetracarboxylic dianhydride (HPMDA) used was changed from 2.24 g (10.0 mmol) to 0.90 g (4.00 mmol), and dimethylacetamide (N, N -Dimethylacetamide) was changed from 23.7 g to 9.4 g, and γ-butyrolactone was used from 17.9 g to 7.1 g. Furthermore, a colorless transparent film (polyimide film) made of polyimide was performed in the same manner as in Example 7 except that the amount of triethylamine used was changed from 0.040 g (0.40 mmol) to 0.020 g (0.20 mmol). Got. The film thickness of the polyimide film thus obtained was 51 μm.

In addition, in order to identify the molecular structure of the compound forming the film thus obtained, an IR spectrum was measured using an IR measuring device (trade name: FT / IR-4100, manufactured by JASCO Corporation). However, since the C═O stretching vibration of imidecarbonyl was observed at 1703 cm ⁻¹ and 1773 cm ⁻¹ , it was confirmed that the compound constituting the obtained film was polyimide. Table 7 shows the evaluation results of the properties of the obtained polyimide film.

  As is clear from the results shown in Table 7, it was confirmed that the polyimide of the present invention (Example 7) had a sufficiently high level of transparency from the values of total light transmittance and HAZE. It was confirmed to have a sufficiently high level of heat resistance from the 5% weight loss temperature. Moreover, from the contrast of the polyimide obtained in Example 7 (the polyimide of the present invention) and the polyimide obtained in Comparative Example 7, when m-Tol is mixed with aromatic diamine (Example 7). Further, it has been found that the pencil hardness can be further improved. From such a result, according to the polyimide of the present invention (Example 7), it was confirmed that it was possible to make the hardness higher while having sufficiently high transparency and heat resistance.

  As described above, according to the present invention, polyimide having sufficiently high heat resistance and transparency and capable of further improving the hardness, and the polyimide are efficiently and reliably produced. It is possible to provide a method for producing polyimide that can be used. Furthermore, according to this invention, it also becomes possible to provide the polyimide solution and polyimide film which are obtained using the said polyimide.

  Therefore, the polyimide of the present invention is, for example, a flexible wiring board, a heat-resistant insulating tape, an electric wire enamel, a semiconductor protective coating, a liquid crystal alignment film, an organic EL substrate, an organic EL transparent electrode substrate, an organic EL lighting film, an organic EL TFT substrate, solar cell transparent electrode substrate, electronic paper transparent electrode substrate, various gas barrier film substrates, touch panel film, flexible display front film, flexible display back film, etc. It is.

Claims (6)

The following general formula (1):
[In the formula (1), X represents the following general formula (I-1):
(In Formula (I-1), R ¹ , R ² , and R ³ each independently represent one selected from the group consisting of a hydrogen atom, an alkyl group having 1 to 10 carbon atoms, and a fluorine atom, and n Represents an integer of 0 to 12.)
And a group represented by the following general formula (I-2):
(In formula (I-2), A is 1 selected from the group consisting of a divalent aromatic group which may have a substituent and has 6 to 30 carbon atoms to form an aromatic ring. And R ⁵ is independently selected from the group consisting of a hydrogen atom and an alkyl group having 1 to 10 carbon atoms.)
Any one group selected from the group consisting of groups represented by:
R ¹⁰ represents an arylene group having 6 to 40 carbon atoms. ]
Containing two or more types of repeating units represented by:
In at least one of the two or more repeating units, R ¹⁰ in the formula (1) is represented by the following general formula (2):
The polyimide characterized by being the repeating unit (A) which is group represented by these.   2. The polyimide according to claim 1, wherein the content of the repeating unit (A) is 25 to 75 mol% in a molar ratio with respect to the total amount of the repeating unit represented by the general formula (1). Of the two or more types of repeating units, at least one of the repeating units other than the repeating unit (A) is such that R ¹⁰ in the formula (1) is represented by the following general formulas (3) to (4):
[Q in the formula (3) has the _{formula: -C 6 H 4 -, -} CONH-C 6 H 4 -NHCO -, - NHCO-C 6 H 4 -CONH -, - O-C 6 H 4 -CO _{-C 6 H 4 -O -, -} OCO-C 6 H 4 -COO -, - OCO-C 6 H 4 -C 6 H 4 -COO -, - OCO -, - NC 6 H 5 -, - CO- _{C 4 H 8 N 2 -CO -} , - C 13 H 10 -, - O -, - S -, - CO -, - CONH -, - SO 2 -, - C (CF 3) 2 -, - C ( _{, - - CH 3) 2 CH} 2 -, - (CH 2) 2 -, - (CH 2) 3 -, - (CH 2) 4 -, - (CH 2) 5 -, - O-C 6 H 4 _{-C (CH 3) 2 -C 6} H 4 -O -, - O-C 6 H 4 -SO 2 -C 6 H 4 -O -, - C (CH 3) 2 -C 6 H 4 -C ( CH _{3) -,} - shows the _{O-C 6 H 4 -C 6} H 4 -O- and _{-O-C 6} H 1 kind selected from the group consisting of groups represented by 4 -O-. ]
The polyimide according to claim 1, wherein the polyimide is a repeating unit (B) that is any one of the groups represented by the formula: In the presence of a polymerization solvent,
The following general formula (5A):
[In Formula (5A), R ¹ , R ² , and R ³ each independently represent one selected from the group consisting of a hydrogen atom, an alkyl group having 1 to 10 carbon atoms, and a fluorine atom, and n is 0. An integer of ~ 12 is shown. ]
And a compound represented by the following general formula (5B):
[In the formula (5B), A represents a kind selected from the group consisting of a divalent aromatic group which may have a substituent and has 6 to 30 carbon atoms to form an aromatic ring. And R ⁵ is independently selected from the group consisting of a hydrogen atom and an alkyl group having 1 to 10 carbon atoms. ]
At least one tetracarboxylic dianhydride selected from the compounds represented by:
The following general formula (6):
_{^{H 2 N-R 10 -NH 2}} (6)
[In formula (6), R ¹⁰ represents an arylene group having 6 to 40 carbon atoms. ]
And at least one of the aromatic diamines contains the following general formula (7):
A mixture of aromatic diamines that are 4,4′-diamino-2,2′-dimethylbiphenyl represented by:
By reacting
The following general formula (1):
[In the formula (1), X represents the following general formula (I-1):
(In Formula (I-1), R ¹ , R ² , and R ³ each independently represent one selected from the group consisting of a hydrogen atom, an alkyl group having 1 to 10 carbon atoms, and a fluorine atom, and n Represents an integer of 0 to 12.)
And a group represented by the following general formula (I-2):
(In formula (I-2), A is 1 selected from the group consisting of a divalent aromatic group which may have a substituent and has 6 to 30 carbon atoms to form an aromatic ring. And R ⁵ is independently selected from the group consisting of a hydrogen atom and an alkyl group having 1 to 10 carbon atoms.)
Any one group selected from the group consisting of groups represented by:
R ¹⁰ represents an arylene group having 6 to 40 carbon atoms. ]
Containing two or more types of repeating units represented by:
In at least one of the two or more repeating units, R ¹⁰ in the formula (1) is represented by the following general formula (2):
A polyimide production method comprising obtaining a polyimide which is a repeating unit (A) which is a group represented by the formula:   A polyimide solution comprising the polyimide according to any one of claims 1 to 3 and an organic solvent.   It is a film which consists of a polyimide as described in any one of Claims 1-3, The polyimide film characterized by the above-mentioned.