JP2013014759A - Polyimide resin molding and method of producing the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a polyimide resin molding excellent in processability, and a method of producing the same.SOLUTION: The method of producing the polyimide resin molding includes: a process for obtaining a polyimide resin solution by imidizing a polyamic acid resin and/or a polyamic acid ester resin in the presence of a solvent; a process for obtaining a polyimide resin by removing the solvent from the polyimide resin solution; and a process for melt-molding the polyimide resin. The polyimide resin includes a repeating unit represented by general formula (1) (wherein Rrepresents a divalent organic group).

Description

  The present invention relates to a polyimide resin molded article excellent in transparency and heat resistance obtained by molding a transparent polyimide resin having a specific skeleton, and a method for producing the same.

Polyimide resins have excellent properties in terms of heat resistance, mechanical properties, chemical resistance, electrical properties, etc., so they are widely used in the automotive, aerospace industry, electrical, electronic, and battery fields. .
However, a polyimide resin is a thermosetting resin that does not have a clear glass transition temperature even though it has excellent heat resistance. When used as a molding material, a special technique such as sintering must be used. In order to obtain a processed product having a complicated shape by the sintering method, a complicated and complicated processing process such as cutting the desired shape from the polyimide block using a cutting machine such as an NC lathe is required. There was a problem.

  Therefore, in order to improve the moldability, a thermoplastic polyimide resin that can be melt-molded at a certain temperature or higher has been developed in the same manner as general-purpose thermoplastic resins. For example, Patent Document 1 describes a thermoplastic polyimide resin having a 3,3 ', 4,4'-diphenyl ether tetracarboxylic acid skeleton as a basic skeleton. Moreover, the method of imidating the polyamic acid resin solution which is a polyimide precursor in a solution, and obtaining a polyimide resin is described.

Patent Document 2 describes a transparent polyimide resin using a dicyclohexyl-3,4,3 ′, 4′-tetracarboxylic dianhydride skeleton, and molding and heating imidization of a polyamic acid solution by a solution casting method. Describes a method for obtaining a transparent polyimide resin molding.
Patent Document 3 describes a method of obtaining a polyimide resin by imidizing a polyamic acid resin having an aliphatic tetracarboxylic acid skeleton in a solution.

JP-A-4-331231 JP-A-8-104750 JP 2005-15629 A

  However, since the polyimide resin described in Patent Document 1 has a high glass transition temperature and crystallinity, a high temperature of 450 ° C. or higher is necessary to obtain a molten state, and there is a problem that a large process load is required. there were. In addition, since the polyimide resin obtained because it has a wholly aromatic skeleton is colored, there is a problem that it is not suitable for a member that requires transparency.

In addition, the technique disclosed in Patent Document 2 is a technique for forming a polyamic acid solution by a solution casting method such as a solution casting method in order to obtain a polyimide resin film. There are problems such as being limited, the time required for drying the solvent, and the cost.
Furthermore, according to the study by the present inventors, a polyimide resin produced by imidizing a polyamic acid resin in a solid state has problems such as low fluidity when melted and a large amount of gel components. Needs improvement.

On the other hand, Patent Document 3 describes a solution casting method in which a polyimide resin is mixed with a solvent in a solution state. However, as in Patent Document 2, only a thin-film structure can be made and its application is limited. However, there are problems such as the time required for drying the solvent and the cost for the drying.
Also, in the method of obtaining a polyimide resin molded body by melt-molding a polyimide resin solution mixed with a solvent, the polyimide resin contains a solvent, so that problems such as significant foaming at the time of melting and generation of flammable gas are caused. Is likely to occur, and this point also needs improvement.

In view of the above, an object of the present invention is to obtain a polyimide resin molded body having excellent properties by using a polyimide resin that can be easily molded in a molten state.
As a result of intensive studies, the present inventors have found that a polyimide resin obtained by imidizing a polyamic acid resin having a specific structure in a solvent is suitable for melt molding, leading to the present invention.
That is, the gist of the present invention is as follows.
[1] A step of imidizing a polyamic acid resin and / or a polyamic acid ester resin in the presence of a solvent to obtain a polyimide resin solution, a step of removing the solvent from the polyimide resin solution to obtain a polyimide resin, and the polyimide resin A method for producing a polyimide resin molded body, comprising a step of melt molding, wherein the polyimide resin includes a repeating unit represented by the following general formula (1).

(In formula (1), R ¹ represents a divalent organic group.)
[2] The method for producing a polyimide resin molded article according to [1], wherein R ¹ is represented by the following formula (2).

(In Formula (2), each of ring A and ring B independently represents an aromatic ring which may have a substituent or an aliphatic ring which may have a substituent, and p and q are Each independently represents an integer of 0 to 10. X represents a direct bond, an oxygen atom, a sulfur atom, an alkylene group which may have a substituent, a sulfonyl group, a sulfinyl group, a sulfide group, a carbonyl group, or a substituent. aromatic group which may have a, -NH-C (= O) -, -. NH-, or _{-O-C n H 2n -O- (} n is an integer of from 1 to 5) shows the proviso, p and q are not both 0. Y ¹ and Y ² are each independently a direct bond, an oxygen atom, a sulfur atom, an alkylene group which may have a substituent, a sulfonyl group, a sulfinyl group, Represents a sulfide group or a carbonyl group, and a plurality of Y ¹ , Y ² , ring A and ring B are May be different.)
[3] X is a direct bond, an oxygen atom, a sulfur atom, an alkylene group that may have a substituent, a sulfonyl group, a sulfinyl group, a sulfide group, a carbonyl group, or an aromatic group that may have a substituent , -NH-, or (n 1 to 5 integer) _-O-C n H 2n -O- is, the production method of the polyimide resin molded article according to claim [2].
[4] A polyimide resin molded article obtained by melt-molding a polyimide resin containing a repeating unit represented by the following general formula (1).

(In formula (1), R ¹ represents a divalent organic group.)
[5] The polyimide resin molded article according to [4], wherein R ¹ is represented by the following formula (2).

(In Formula (2), each of ring A and ring B independently represents an aromatic ring which may have a substituent or an aliphatic ring which may have a substituent, and p and q are Each independently represents an integer of 0 to 10. X represents a direct bond, an oxygen atom, a sulfur atom, an alkylene group which may have a substituent, a sulfonyl group, a sulfinyl group, a sulfide group, a carbonyl group, or a substituent. aromatic group which may have a, -NH-C (= O) -, -. NH-, or _{-O-C n H 2n -O- (} n is an integer of from 1 to 5) shows the proviso, p and q are not both 0. Y ¹ and Y ² are each independently a direct bond, an oxygen atom, a sulfur atom, an alkylene group which may have a substituent, a sulfonyl group, a sulfinyl group, when a sulfide group, or .p or q indicates a carbonyl group is two or more, a plurality of Y ^{1, 2,} ring A and ring B each may be different from one another.)
[6] X is a direct bond, an oxygen atom, a sulfur atom, an alkylene group which may have a substituent, a sulfonyl group, a sulfinyl group, a sulfide group, a carbonyl group or an aromatic group which may have a substituent , —NH—, or —O—C _n H _2n —O— (n is an integer of 1 to 5), [5].

According to the present invention, since a polyimide resin having high fluidity at the time of melting is passed, the processability at the time of melt molding is improved. Moreover, since the polyimide resin according to the present invention can be molded at a lower temperature than a thermoplastic polyimide resin having a wholly aromatic skeleton, the process load is less. Furthermore, since the polyimide resin of the present invention has a low solvent content, the polyimide resin of the present invention is also excellent in that it does not generate foaming or flammable gas during melt molding. Thus, according to this invention, the manufacturing method of a highly practical polyimide molded object can be provided. In addition, according to the present invention, a polyimide resin molded body with less physical non-uniformity such as voids and unevenness and non-uniformity of optical characteristics can be obtained.

The method for producing a polyimide resin molded body according to the present invention includes:
1. A step of imidizing a polyamic acid resin and / or a polyamic acid ester resin in the presence of a solvent to obtain a polyimide resin solution;
2. Removing the solvent from the polyimide resin solution to obtain a polyimide resin;
3. Melt-molding the polyimide resin.
The polyimide resin contains a repeating unit represented by the following general formula (1).

(In Formula (1), R ¹ represents a divalent organic group.)
According to this method, a polyimide resin having high fluidity at the time of melting can be prepared by imidizing the polyamic acid resin or the polyamic acid ester resin in the presence of a solvent, so that the processability at the time of melt molding is improved.
Moreover, since generation | occurrence | production of the water accompanying the spin-drying | dehydration ring closure at the time of shaping | molding a polyimide resin can change polyamic acid resin to a polyimide resin, generation | occurrence | production of the defect of a polyimide resin molded object can be suppressed. And since the polyimide resin with low solvent content is melt-molded, foaming at the time of molding can be suppressed, and a polyimide resin molded body with less physical non-uniformity such as voids and irregularities and non-uniformity of optical properties can be obtained.

[1. Step of obtaining a polyimide resin solution by imidizing a polyamic acid resin and / or a polyamic acid ester resin in the presence of a solvent]
Hereinafter, a process of obtaining a polyimide resin solution by imidizing a polyamic acid resin and / or a polyamic acid ester resin in the presence of a solvent will be described.
<1.1 Polyamic acid resin and / or polyamic acid ester resin>
The polyamic acid resin is obtained by reacting a tetracarboxylic dianhydride represented by the general formula (E1) with a diamine compound represented by the general formula (E2) in a solvent.

R ¹ in the general formula (E2) is not particularly limited as long as it is a divalent organic group, but a group represented by the following general formula (2) is preferable.

In formula (2), ring A and ring B each independently represent an aromatic ring which may have a substituent or an aliphatic ring which may have a substituent. Ring A and ring B may be a single ring or a condensed ring. In addition, when p or q is 2 or more, R ¹ has a plurality of rings A or B, but these rings A or B may be rings having the same structure or different from each other. It may be a ring of structure.

  The aromatic ring is not particularly limited, and examples thereof include an aromatic hydrocarbon ring and an aromatic heterocyclic ring. Examples of the aromatic hydrocarbon ring include benzene ring, naphthalene ring, azulene ring, biphenyl ring, acenaphthylene ring, fluorene ring, phenanthrene ring, anthracene ring, fluoranthene ring, triphenyl ring, terphenyl ring, pyrene ring, chrysene ring. , Naphthacene ring, perylene ring, and pentacene ring, and those having 6 to 30 carbon atoms. Carbon number becomes like this. Preferably it is 6-25, More preferably, it is 6-20. Examples of the aromatic heterocyclic ring include those having 2 to 30 carbon atoms such as a pyrrole ring, a furan ring, a thiophene ring, a pyridine ring, a quinoline ring, and an isoquinoline ring. Carbon number becomes like this. Preferably it is 2-25, More preferably, it is 2-20. Among these, a benzene ring, a biphenylene ring, and a terphenyl ring are preferable.

The aliphatic ring is not particularly limited, but includes a cyclobutane ring, cyclopentane ring, cyclohexane ring, cycloheptane ring, cyclooctane ring, norbornane ring, norbornene ring, hydrindane ring, decahydronaphthalene ring, adamantane ring, etc. The thing of carbon numbers 3-30 is mentioned. Preferably carbon number is 3-25. Among these, a cyclohexane ring, a cyclopentane ring, and a norbornane ring are preferable.
Regarding the aromatic ring or aliphatic ring that is ring A or ring B, the position of bonding to Y ¹ , Y ² , or X is not particularly limited.

Examples of the substituent that the aromatic ring or the aliphatic ring may have include a halogen atom, an alkyl group, an alkoxy group, and a hydroxyl group. Examples of the halogen atom include a fluorine atom, a bromine atom, and a chlorine atom. Examples of the alkyl group include those having 1 to 20 carbon atoms such as a methyl group, an ethyl group, a propyl group, an isopropyl group, a butyl group, and a tertiary butyl group. Examples of the alkoxy group include those having 1 to 20 carbon atoms such as a methoxy group, an ethoxy group, a propoxy group, an isopropoxy group, a butoxy group, and a tertiary butoxy group.

In the formula (2), p and q are each independently an integer of 0 or more, preferably 1 or more, and on the other hand, an integer of 10 or less, preferably 5 or less.
In the formula (2), X is a direct bond, an oxygen atom, a sulfur atom, an alkylene group which may have a substituent, a sulfonyl group, a sulfinyl group, a sulfide group, a carbonyl group, and an aromatic which may have a substituent. Represents a group, —NH—C (═O) —, —NH—, or —O—C _n H _2n —O—. However, n represents an integer of 1 to 5, and neither p nor q is 0.
Among these, a direct bond, an oxygen atom, a sulfur atom, an alkylene group which may have a substituent, a sulfonyl group, a sulfinyl group, a sulfide group, a carbonyl group, an aromatic group which may have a substituent, —NH— or —O—C _n H _2n —O— is preferable, and a direct bond, an oxygen atom, an alkylene group which may have a substituent, a sulfinyl group, or a sulfonyl group is more preferable. Particularly preferred is an atom, an alkylene group which may have a substituent, or a sulfinyl group.

Although there is no special restriction | limiting as an alkylene group, It is preferable that it is a C1-C20 alkylene group, and it is more preferable that it is a C1-C10 alkylene group. Specific examples of the alkylene group include a methylene group, an ethylene group, a propylene group, a butylene group, a pentylene group, a hexylene group, and a 2,2-propanediyl group.
The aromatic group is not particularly limited, and examples thereof include an aromatic hydrocarbon group and an aromatic heterocyclic group. Examples of the aromatic hydrocarbon group include those having 6 to 30 carbon atoms such as a phenylene group, a biphenylene group, a naphthylene group, a phenanthrene group, a triphenylene group, a terphenylene group, a pyrenylene group, and a fluorene group. Examples of the aromatic heterocyclic group include those having 2 to 30 carbon atoms such as a pyridylene group and a quinolylene group. Among these, a phenylene group, a naphthylene group, and a pyridylene group are preferable.

Examples of the substituent that the alkylene group or aromatic group may have include an alkyl group having 1 to 5 carbon atoms, a hydroxy group, an alkoxy group, an amino group, a carboxyl group, and an epoxy group. These substituents may be further substituted with a halogen atom such as a fluorine atom or a chlorine atom.
Y ¹ and Y ² each independently represent a direct bond, an oxygen atom, a sulfur atom, an alkylene group which may have a substituent, a sulfonyl group, a sulfinyl group, a sulfide group, or a carbonyl group. Among these, a direct bond or an oxygen atom is preferable. When p or q is 2 or more, R ¹ includes a plurality of Y ¹ and Y ^2, and the plurality of Y ¹ and Y ² may have the same structure or different structures. There may be. Here, as the alkylene group which may have a substituent, the same groups as those mentioned for X can be used.

It is preferable that the ring A and the ring B have the same structure, and it is also preferable that Y ¹ and Y ² have the same structure.
More preferable examples of R ¹ include those represented by the following general formula (3) or (4).

Equation (3) corresponds to the case where p = 2 and q = 2 in Equation (2). In Formula (3), Ring A, Ring B, Ring C, and Ring D represent the same structure as Ring A and Ring B in Formula (2). Y ¹ , Y ² , Y ³ , and Y ⁴ represent the same structure as Y ¹ and Y ² in Formula (2). Similarly to formula (2), ring A, ring B, ring C and ring D may be different from each other, and Y ¹ , Y ² , Y ³ and Y ⁴ may be different from each other. It is also preferable that the ring A and the ring B have the same structure, and it is also preferable that the ring C and the ring D have the same structure. It is also preferable that Y ¹ and Y ² have the same structure, and it is also preferable that Y ³ and Y ⁴ have the same structure.
In formula (3), ring A, ring B, ring C and ring D are preferably aromatic rings which may have a substituent, and are phenylene groups which may be substituted with a halogen atom. Is more preferable, and a phenylene group is particularly preferable. Y ¹ and Y ² are preferably a direct bond, an oxygen atom, or a sulfur atom. Preferable examples of Y ³ and Y ⁴ include direct bonding.

Equation (4) corresponds to the case where p = 1 and q = 1 in Equation (2). In Formula (4), Ring A and Ring B represent the same structure as Ring A and Ring B in Formula (2). Y ¹ and Y ² represent the same structure as Y ¹ and Y ² in Formula (2). Here, it is also preferable that the ring A and the ring B have the same structure, and it is also preferable that Y ¹ and Y ² have the same structure.
In the formula (4), the ring A and the ring B are preferably an aromatic ring which may have a substituent or an aliphatic ring which may have a substituent, and is substituted with a halogen atom. More preferred is a phenylene group, and particularly preferred is a phenylene group. Preferred examples of ^{Y 1} and ^{Y 2} is a direct bond.

Specific examples of the diamine compound (H ₂ N—R ¹ —NH ₂ ) represented by the general formula (E2) include the diamine compounds shown below. That is, a divalent substituent obtained by removing two primary amino groups from the diamine compound shown below can be used as R ¹ . Specific examples of such diamine compounds include 1,4-phenylenediamine, 1,2-phenylenediamine, 1,3-phenylenediamine, 4,4′-diaminodiphenyl ether, 3,4′-diaminodiphenyl ether, 1, 4-bis (4-aminophenoxy) benzene, 1,3-bis (4-aminophenoxy) benzene, 2,2-bis (4- (4-aminophenoxy) phenyl) propane, 2,2-bis (4- (4-aminophenoxy) phenyl) hexafluoropropane, bis (4- (4-aminophenoxy) phenyl) sulfone, bis (4- (3-aminophenoxy) phenyl) sulfone, 1,3-bis (4-aminophenoxy) ) Neopentane, 4,4'-diamino-3,3'-dimethylbiphenyl, 4,4'-diamino-2,2'-dimethyl Rubiphenyl, 4,4′-diamino-2,2′-bis (trifluoromethyl) biphenyl, 4,4′-bis (4-aminophenoxy) biphenyl, 4,4′-diamino-3,3′-dihydroxy Biphenyl,
Bis (4-amino-3-carboxyphenyl) methane, 4,4′-diaminodiphenylsulfone, bis (4- (4-aminophenoxy) phenyl) sulfone, 4,4′-diaminodiphenyl sulfide, N- (4- Aminophenoxy) -4-aminobenzamine, 1,4-diaminocyclohexane, 4,4'-methylenebis (cyclohexylamine), 4,4'-methylenebis (2-methylcyclohexylamine), N- (4-aminophenyl) Examples include -4-aminobenzamide and N, N′-bis (4-aminophanyl) terephthalamide. Among these, 4,4′-diaminodiphenyl ether, 1,3-bis (4-aminophenoxy) benzene, 2,2-bis (4- (4-aminophenoxy) phenyl) propane, 2,2-bis (4- (4-aminophenoxy) phenyl) hexafluoropropane, bis (4- (4-aminophenoxy) phenyl) sulfone, 4,4′-diamino-3,3′-dimethylbiphenyl or 4,4′-methylenebis (cyclohexylamine) Having a divalent substituent obtained by removing an amino group from R) as R ¹ is preferable in that the transparency, heat resistance, and mechanical strength of the polyimide resin described later can be achieved simultaneously, and more preferably, 4,4′-diaminodiphenyl ether, 2,2-bis (4- (4-aminophenoxy) phenyl) propane, 2, Obtained by removing the amino group from -bis (4- (4-aminophenoxy) phenyl) hexafluoropropane, bis (4- (4-aminophenoxy) phenyl) sulfone or 4,4'-methylenebis (cyclohexylamine) It is a divalent substituent.

  The polyamic acid ester resin is formed by ring-opening the tetracarboxylic dianhydride represented by the general formula (E1) using an alcohol such as methanol, ethanol, isopropanol, n-propanol, isobutanol or n-butanol. Diesterification can be performed by reacting the obtained diester with a diamine compound represented by the general formula (E2) in a solvent.

The alcohol used for the diesterification is not particularly limited, but usually an alkyl alcohol is used. The alcohol usually has 1 or more carbon atoms, and is usually 14 or less, preferably 10 or less, more preferably 4 or less, and even more preferably 2 or less.
Furthermore, the polyamic acid ester resin can also be obtained by esterifying the carboxylic acid group of the polyamic acid resin obtained as described above by reacting with the alcohol as described above.

As the alcohol used for the esterification, the same alcohol as used for the diesterification can be used.
In the reaction for obtaining a polyamic acid resin or a polyamic acid ester resin, only one diamine compound may be used, or a mixture of two or more diamine compounds may be used.
The tetracarboxylic dianhydride represented by the general formula (E1) is mixed with other tetracarboxylic dianhydrides to such an extent that the colorlessness, transparency and various physical properties of the polyimide resin according to the present invention are not impaired. May be. 1 type may be sufficient as the tetracarboxylic dianhydride mixed, and 2 or more types may be sufficient as it.

The tetracarboxylic dianhydride that may be mixed is not limited as long as the object of the present invention is not impaired. For example, ethylenetetracarboxylic dianhydride, butanetetracarboxylic dianhydride, cyclopentanetetracarboxylic dianhydride, 1,2,4,5-cyclohexanetetracarboxylic dianhydride, 1,2,3,4 -Cyclohexanetetracarboxylic dianhydride, pyromellitic dianhydride, 1,1-bis (2,3-dicarboxyphenyl) ethane dianhydride, bis (2,3-dicarboxyphenyl) methane dianhydride, Bis (3,4-dicarboxyphenyl) methane dianhydride, 3,3 ′, 4,4′-biphenyltetracarboxylic dianhydride, 2,2-bis (3,4-dicarboxyphenyl) propane dianhydride 2,2-bis (2,3-dicarboxyphenyl) propane dianhydride, 2,2-bis (3,4-dicarboxyphenyl) -1,1,1,3,3,3-hexene Fluoropropane dianhydride, 2,2-bis (2,3-dicarboxyphenyl) -1,1,1,3,3,3-hexafluoropropane dianhydride, bis (3,4-dicarboxyphenyl) Sulfone dianhydride, bis (3,4-dicarboxyphenyl) ether dianhydride, bis (2,3-dicarboxyphenyl) ether dianhydride, 3,3 ′, 4,4′-benzophenone tetracarboxylic acid Anhydride, 2,2 ′, 3,3′-benzophenonetetracarboxylic dianhydride, 4,4- (p-phenylenedioxy) diphthalic dianhydride, 4,4- (m-phenylenedioxy) diphthal Acid dianhydride, 1,2,5,6-naphthalenedicarboxylic dianhydride, 1,4,5,8-naphthalenedicarboxylic dianhydride, 2,3,6,7-naphthalenedicarboxylic dianhydride, 1, 2, , 4-Benzenetetracarboxylic dianhydride, 2,2 ′, 6,6′-biphenyltetracarboxylic dianhydride, 3,4,9,10-perylenetetracarboxylic dianhydride, 2,3,6 , 7-anthracenetetracarboxylic dianhydride, 1,2,7,8-phenanthrenetetracarboxylic dianhydride, and the like.

In addition, tetracarboxylic dianhydrides having an aromatic ring such as pyromellitic dianhydride and tetracarboxylic dianhydrides having a rigid skeleton such as 1,2,4,5-cyclohexanetetracarboxylic dianhydride If excessively used, solubility of the resulting polyimide resin in a solvent, colorlessness, transparency, and various physical properties may be impaired.
The reaction of the tetracarboxylic dianhydride represented by the general formula (E1) and the diamine compound represented by the general formula (E2) can be carried out under conventionally known conditions. There are no particular limitations on the order of addition or addition method of the tetracarboxylic dianhydride and the diamine compound. For example, a polyamic acid resin can be obtained by sequentially adding a tetracarboxylic dianhydride and a diamine compound to a solvent and stirring at an appropriate temperature.

The amount of the diamine compound is usually 0.8 mol or more, preferably 1 mol or more with respect to 1 mol of tetracarboxylic dianhydride. On the other hand, it is 1.2 mol or less normally, Preferably it is 1.1 mol or less. By making the quantity of a diamine compound into such a range, the yield of the polyamic acid resin obtained can be improved.
The concentration of the tetracarboxylic dianhydride and the diamine compound in the solvent can be appropriately set according to the reaction conditions and the viscosity of the polyamic acid resin solution. For example, the total weight of the tetracarboxylic dianhydride and the diamine compound is not particularly limited, but is usually 1% by weight or more, preferably 5% by weight or more with respect to the total amount of solution, while usually 70%. % By weight or less, preferably 30% by weight or less. By setting the amount of the reaction substrate in such a range, a polyamic acid resin can be obtained at a low cost and in a high yield.

  The reaction temperature is not particularly limited, but is usually 0 ° C. or higher, preferably 20 ° C. or higher, and is usually 100 ° C. or lower, preferably 80 ° C. or lower. The reaction time is not particularly limited, but is usually 1 hour or more, preferably 2 hours or more, while it is usually 100 hours or less, preferably 24 hours or less. By performing the reaction under such conditions, a polyamic acid resin can be obtained at a low cost and in a high yield. The pressure during the reaction may be normal pressure, increased pressure, or reduced pressure. The atmosphere may be air or an inert atmosphere.

Solvents used in this reaction include hydrocarbon solvents such as hexane, cyclohexane, heptane, benzene, toluene, xylene and mesitylene; carbon tetrachloride, methylene chloride, chloroform, 1,2-dichloroethane, chlorobenzene, dichlorobenzene and fluorobenzene. Halogenated hydrocarbon solvents such as diethyl ether, tetrahydrofuran, 1,4-dioxane and methoxybenzene; ether solvents such as acetone, methyl ethyl ketone, cyclohexanone and methyl isobutyl ketone; N, N-dimethylformamide, N Amide solvents such as N, dimethylacetamide and N-methyl-2-pyrrolidone; aprotic polar solvents such as dimethyl sulfoxide; pyridine, picoline, lutidine, quinoline and i Heterocyclic solvents such as quinoline; phenol solvents such as phenol and cresol; lactone solvents such as γ-butyrolactone, γ-valerolactone, and δ-valerolactone, etc., but are not particularly limited. . As the solvent, one kind of substance can be used, or two or more kinds of substances can be mixed and used.

  The polyamic acid resin or polyamic acid ester resin obtained by reacting the tetracarboxylic dianhydride represented by the general formula (E1) with the diamine compound represented by the general formula (E2) mainly includes the following general A repeating unit represented by the formula (B1), (B2), or (B3) is included.

In the general formulas (B1), (B2), and (B3), R ² is not limited as long as the polyimide resinization described later is performed, but is usually a portion obtained by removing a hydroxyl group from a hydrogen atom or an alcohol used for the esterification. . Specifically, the C1-C14 alkyl group which may have a substituent is shown. Although there is no special restriction | limiting as an alkyl group, Usually, it is a C1-C14 alkyl group, A C1-C10 alkyl group is preferable, a methyl group, an ethyl group, n-propyl group, isopropyl group, n- A butyl group or an isobutyl group is more preferable, and a methyl group or an ethyl group is still more preferable. Examples of the substituent that the alkyl group may have include a halogen atom.

In the polyamic acid resin or polyamic acid ester resin obtained in the present invention, the abundance ratio of the repeating structure represented by the general formulas (B1), (B2), and (B3) is not particularly limited.
The polyimide resin according to the present invention can be obtained by imidizing the polyamic acid resin or polyamic acid ester resin thus obtained by the method described later.

<1.2 Imidization>
The polyamic acid resin or polyamic acid ester resin described above is subjected to dehydration cyclization or dealcoholization cyclization (hereinafter collectively referred to as imidization) in the presence of a solvent to produce a polyimide resin. This method is preferable in that a polyimide resin having high fluidity upon melting can be obtained.
The imidization can be performed using any conventionally known method, and examples thereof include thermal imidization by thermal cyclization and chemical imidization by chemical cyclization. These imidization reactions may be used alone or in combination.

(1.2.1 Heat imidization)
Below, the method of the heat imidation in a solution is demonstrated.
A polyimide resin solution can be obtained by heating a polyamic acid resin or a polyamic acid ester resin in the presence of a solvent.
Examples of the solvent used when imidizing the polyamic acid resin or the polyamic acid ester resin include the solvents used in the reaction for obtaining the polyamic acid resin or the polyamic acid ester resin. Among them, amide solvents such as N, N-dimethylformamide, N, N-dimethylacetamide and N-methyl-2-pyrrolidone are highly soluble in polyamic acid resin, polyamic acid ester resin and polyimide resin, and have a boiling point. This is preferable because the imidization reaction proceeds efficiently.

In this case, water (or alcohol) generated by the imidization reaction inhibits the ring closure reaction, and thus is preferably discharged out of the reaction system. For example, a method may be used in which water is discharged out of the system by mixing an azeotropic solvent such as toluene or xylene and azeotroping with water.
The concentration of the polyamic acid resin or polyamic acid ester resin in the imidization reaction solution is not particularly limited, but is usually 5% by weight or more, preferably 10% by weight or more, more preferably 20% by weight or more, and usually 80% by weight or less. Preferably it is 60 weight% or less, More preferably, it is 40 weight% or less. 20% by weight or more is preferable in terms of high production efficiency, and 40% by weight or less is preferable in that the solution viscosity is easy to handle in ordinary manufacturing equipment.

  The imidation reaction temperature is not particularly limited, but is usually 50 ° C or higher, preferably 80 ° C or higher, more preferably 120 ° C or higher, and usually 300 ° C or lower, preferably 280 ° C or lower, more preferably 250 ° C or lower. . It is preferable in that the imidization reaction proceeds efficiently when the temperature is 120 ° C or higher, and it is preferable in that the side reaction other than the imidization reaction is suppressed when the temperature is 250 ° C or lower. The pressure during the reaction may be normal pressure, increased pressure, or reduced pressure. The atmosphere may be air or an inert atmosphere.

  Moreover, tertiary amines etc. can also be added as a catalyst which accelerates | stimulates imidation. Specifically, trimethylamine, triethylamine, tripropylamine, tributylamine, tritanolamine, N, N-dimethylethanolamine, N, N-diethylethanolamine, triethylenediamine, N-methylpyrrolidine, N-ethylpyrrolidine, N- Methylpiperidine, N-ethylpiperidine, imidazole, pyridine, quinoline, isoquinoline, and the like can be used as a catalyst. The amount of the catalyst used is preferably from 0.1 to 100 mol%, more preferably from 1 to 10 mol%, based on the carboxyl group or ester group. When the amount of the catalyst used is in such a range, the reaction can be performed at a low cost and with a high yield.

(1.2.2 Chemical imidization)
The case where chemical imidation is used as the imidation method will be described below.
A polyimide resin solution can be obtained by chemically imidizing a polyamic acid resin or a polyamic acid ester resin in the presence of a solvent.
Examples of the solvent used when imidizing the polyamic acid resin or the polyamic acid ester resin include the solvent for the heating imidization.

The concentration of the polyamic acid resin or polyamic acid ester resin in the imidization reaction solution is not particularly limited, but is usually 5% by weight or more, preferably 10% by weight or more, more preferably 20% by weight or more, and usually 80% by weight or less. Preferably it is 60 weight% or less, More preferably, it is 40 weight% or less. 20% by weight or more is preferable in terms of high production efficiency, and 40% or less is preferable in that the solution viscosity is easy to handle with ordinary manufacturing equipment. The imidation reaction temperature is not particularly limited, but is usually 50 ° C or higher, preferably 80 ° C or higher, more preferably 120 ° C or higher, and usually 300 ° C or lower, preferably 280 ° C or lower, more preferably 250 ° C or lower. . It is preferable in that the imidization reaction proceeds efficiently by being 120 ° C. or higher, and it is preferable in that the side reaction other than the imidization reaction is suppressed by being 250 ° C. or lower. The pressure during the reaction may be normal pressure, increased pressure, or reduced pressure. The atmosphere may be air or an inert atmosphere.
Further, a tertiary amine or the like can be added as a catalyst for promoting imidization in the same manner as in the heating imidization.

  N, N-2-substituted carbodiimide such as N, N-dicyclohexylcarbodiimide or N, N-diphenylcarbodiimide; acid anhydride such as acetic anhydride or trifluoroacetic anhydride; chloride such as thionyl chloride or tosyl chloride Acetyl chloride, acetyl bromide, propionyl iodide, acetyl fluoride, propionyl chloride, propionyl bromide, propionyl iodide, propionyl fluoride, isobutyryl chloride, isobutyryl bromide, isobutyryl iodide, isobutyryl fluoride Ride, n-butyryl chloride, n-butyryl bromide, n-butyryl iodide, n-butyryl fluoride, mono-, di-, tri-chloroacetyl chloride, mono-, di-, tri- Lomoacetyl chloride, mono-, di-, tri-iodoacetyl chloride, mono-, di-, tri-fluoroacetyl chloride, chloroacetic anhydride, phenylphosphonic dichloride, thionyl chloride, thionyl bromide, thionyl iodide or thionyl fluoride Halide compounds such as rides; phosphorus trichloride, triphenyl phosphite, or phosphorous compounds such as diethyl phosphoric acid / BR> V anide can be added. The amount of these dehydrating condensing agents to be used is usually 0.5 mol, preferably 1 mol or more, and usually 20 mol or less, preferably 10 mol or less, relative to 1 mol of the polyamic acid resin or polyamic acid ester resin skeleton. These can be used alone or in combination of two or more.

  Further, the polyamic acid resin or polyamic acid ester resin used in the present invention, the polyimide resin obtained by the present invention and the polyimide resin may be end-capped as necessary. By end-capping, the polyamic acid resin or polyamic acid ester resin and polyimide resin terminal polymerizability are lowered, and this is preferable in that the viscosity of the polyimide resin solution or the melt viscosity of the polyimide resin is stabilized.

The terminal sealing method is not limited, and any conventionally known method may be used. You may seal in any step which prepares a polyamic acid resin, a polyamic acid ester resin, and a polyimide resin. A preferable method includes a method using a terminal blocking agent. For example, when sealing with a terminal blocking agent, as the terminal blocking agent, any conventionally known blocking agent may be used. For example, the terminal blocking agent used when sealing a terminal amino group is used. As acid anhydrides such as phthalic anhydride, 1,2-cyclohexanedicarboxylic anhydride, 4-methylcyclohexane-1,2-dicarboxylic anhydride or (2-methyl-2-propenyl) succinic anhydride; And organic acid chlorides such as benzoic acid chloride. In addition, examples of the terminal blocking agent for sealing the terminal acid anhydride group include amine compounds such as 3-aminophenylacetylene, aniline, and cyclohexylamine.

<1.3 Composition of polyimide resin solution>
The concentration of the polyimide resin in the polyimide resin solution obtained by imidation of the polyamic acid or polyamic acid ester according to the present invention is not particularly limited, but is usually 1% by weight or more, preferably 5% by weight or more, Usually, it is 80% by weight or less, preferably 50% by weight or less. By adjusting the concentration of the polyimide resin in the solution within this range, an extreme increase in viscosity during the reaction can be suppressed, and good workability can be achieved in the subsequent solidification process.

The viscosity of the polyimide resin solution obtained by imidation of the polyamic acid or polyamic acid ester according to the present invention is not particularly limited, but is usually 10 mPa · s or more, preferably 1.0 × 10 ² mPa · s or more. On the other hand, it is usually 5.0 × 10 ⁴ mPa · s or less, preferably 2.0 × 10 ⁴ mPa · s or less. By adjusting the viscosity of the polyimide resin solution within the above range, it is preferable in that the solvent can be easily removed from the polyimide resin solution described later.

The viscosity of the polyimide resin solution is measured at 25 ° C. using an E-type viscometer. The viscosity can be measured by a known method, for example, according to the method described in International Publication No. 99/60622.
Thus, the polyimide resin preferable for melt molding can be prepared by adjusting the substance composition ratio in the polyimide resin solution.

  In the polyimide resin solution obtained by imidization of polyamic acid or polyamic acid ester according to the present invention, the ratio of the unreacted polyamic acid resin or polyamic acid ester resin to the polyimide resin is not particularly limited, but is usually 30% by weight or less. , Preferably 20% by weight or less, more preferably 10% by weight or less. When more than 30% by weight of polyamic acid resin or polyamic acid ester resin is contained in the polyimide resin solution, white turbidity may occur due to phase separation of the polyimide resin and the polyamic acid resin or polyamic acid ester resin. Moreover, when the polyimide resin obtained from the polyimide resin solution which phase-separated nonuniformly is used for melt molding, a molded object also becomes non-uniform | heterogenous and an unevenness | corrugation, white turbidity, etc. may arise in a molded object.

The ratio of the polyamic acid resin or the polyamic acid ester resin to the polyimide resin in the polyimide resin solution is represented by the following formula. Ratio of polyamic acid resin or polyamic acid ester resin in polyimide resin solution to polyimide resin = (substance amount of polyamic acid resin or polyamic acid ester resin in polyimide resin solution) / (polyamic acid resin or polyamic acid in polyimide resin solution) Substance amount of ester resin + substance amount of polyimide resin in polyimide resin solution) × 100
The substance amount of the polyamic acid resin or polyamic acid ester resin in the polyimide resin solution is the weight of the polyamic acid resin or polyamic acid ester resin component contained in the polyimide resin solution represented by the general formulas (B1), (B2) and (B3). ) Divided by the average molecular weight of each repeating unit represented by

The substance amount of the polyimide resin in the polyimide resin solution is obtained by dividing the weight of the polyamic acid resin or polyamic acid ester resin component contained in the polyimide resin solution by the molecular weight of the repeating unit represented by the general formula (1). It is done. Various methods for measuring the amount of polyamic acid resin or polyamic acid ester resin in polyimide resin solution are known, including nuclear magnetic resonance spectroscopy (NMR), Fourier transform infrared spectroscopy (FT-IR method), and imide ring closure. Quantitative determination of water content, method of neutralization titration of carboxylic acid contained in polyamic acid (see JP 2009-269958 A), measurement of luminescence intensity or absorption intensity by labeling specific functional groups (See Japanese Patent No. 4529760).

[Step of removing polyimide from polyimide resin solution to obtain polyimide resin]
The process of obtaining the polyimide resin from the polyimide resin solution is not particularly limited as long as the organic solvent or water contained in the polyimide resin solution can be removed. For example, the polyimide resin solution has a low solubility of the polyimide resin. A method for removing a solvent such as an organic solvent and water by precipitating a polyimide resin by adding a solution therein, separating the deposited polyimide resin according to the present invention, and heating and / or depressurizing the polyimide resin solution. Can be mentioned.

  The solvent for precipitating the polyimide resin can be appropriately selected depending on the type of the polyimide resin, but ethers such as diethyl ether or diisopropyl ether; ketones such as acetone, methyl ethyl ketone, isobutyl ketone or methyl isobutyl ketone; methanol, ethanol or isopropyl alcohol And alcohol. Of these, alcohols such as isopropyl alcohol are preferable in that precipitates can be obtained efficiently, the boiling point is low, and drying is easy.

The temperature at which the polyimide resin is deposited can be suitably selected as appropriate, but is usually 5 ° C. or higher, preferably 10 ° C. or higher, and usually 80 ° C. or lower, preferably 60 ° C. or lower, more preferably 50 ° C. or lower. It is. The time at which the polyimide resin is deposited is not particularly limited, but is usually 30 minutes or longer, preferably 1 hour or longer, and is usually 3 hours or shorter, preferably 2 hours or shorter.
The pressure at the time of polyimide resin deposition may be normal pressure, increased pressure, or reduced pressure. The atmosphere may be air or an inert atmosphere.

  Examples of the method for separating the polyimide resin during precipitation from the solvent include filtration, centrifugation, and sedimentation. Especially, filtration is preferable at the point which can collect | recover polyimide resins efficiently. It is preferable to remove the solvent remaining in the polyimide resin with respect to the solvent and the separated polyimide resin. The method for removing the solvent is not particularly limited as long as the solvent is removed, and specifically, hot air heating, vacuum drying, infrared heating, microwave heating, heating by contact using a hot plate or a hot roll, etc. The processing method is mentioned. Among these, vacuum drying is preferable because the polyimide resin can be efficiently dried in a short time.

A suitable temperature can be appropriately used for removing the solvent, but it is usually 40 ° C. or higher, preferably 60 ° C. or higher, and usually 300 ° C. or lower, preferably 250 ° C. or lower, more preferably 200 ° C. or lower. is there. The time for removing the solvent is not particularly limited, but is usually 30 minutes or longer, preferably 1 hour or longer, and is usually 3 hours or shorter, preferably 2 hours or shorter.
The pressure at the time of removing the solvent is not particularly limited, but is usually 0.01 MPa or more, and usually less than atmospheric pressure, preferably 0.09 MPa or less, more preferably 0.08 MPa or less when drying under reduced pressure.
When the amount of the solvent is small, the solvent such as an organic solvent or water may be removed by heating and / or reducing the pressure of the obtained polyimide resin solution without performing the operation of extracting the polyimide resin.

<2.1 Polyimide resin>
The polyimide resin according to the present invention obtained in the above step includes a repeating unit represented by the following general formula (1).

In the formula (1), R ¹ represents a divalent organic group. Incidentally, the polyimide resin according to the present invention have the general formula (1) for containing a plurality of repeating units represented by include organic groups R ¹ of a plurality of divalent. Here, the plurality of divalent organic groups R ¹ may all have the same structure or different structures.
Thus, the polyimide resin of the present invention is less colored compared to a polyimide resin composed of an aromatic ring such as biphenyl, or a tetracarboxylic acid residue having a monocyclic aliphatic ring as a skeleton, and The effect of improving solubility can be obtained. Moreover, the polyimide resin according to the present invention has relatively high solubility, and the solution concentration can be freely adjusted. Furthermore, the polyimide resin according to the present invention is relatively excellent in heat resistance and transparency.

R ¹ is not particularly limited as long as it is a divalent organic group, but not only a group represented by the general formula (2) can obtain a resin film having high transparency and heat resistance, It is preferable in that coloring due to deterioration of the resin film over time can be reduced and solubility in an organic solvent is improved. In order to obtain these effects, the ratio of the repeating unit represented by the general formula (1) to all the repeating units contained in the polyimide resin is preferably 50% by weight or more, more preferably 70%. % By weight or more, more preferably 90% by weight or more, and most preferably 95% by weight or more.

In formula (2), ring A and ring B each independently represent an aromatic ring which may have a substituent or an aliphatic ring which may have a substituent. Ring A and ring B may be a single ring or a condensed ring. In addition, when p or q is 2 or more, R ¹ has a plurality of rings A or B, but these rings A or B may be rings having the same structure or different from each other. It may be a ring of structure.

The aromatic ring is not particularly limited, and examples thereof include an aromatic hydrocarbon ring and an aromatic heterocyclic ring. Examples of the aromatic hydrocarbon ring include benzene ring, naphthalene ring, azulene ring, biphenyl ring, acenaphthylene ring, fluorene ring, phenanthrene ring, anthracene ring, fluoranthene ring, triphenyl ring, terphenyl ring, pyrene ring, chrysene ring. , Naphthacene ring, perylene ring, and pentacene ring, and those having 6 to 30 carbon atoms. Carbon number becomes like this. Preferably it is 6-25, More preferably, it is 6-20. Examples of the aromatic heterocyclic ring include those having 2 to 30 carbon atoms such as a pyrrole ring, a furan ring, a thiophene ring, a pyridine ring, a quinoline ring, and an isoquinoline ring. Carbon number becomes like this. Preferably it is 2-25, More preferably, it is 2-20. Among these, a benzene ring, a biphenylene ring, and a terphenyl ring are preferable.

The aliphatic ring is not particularly limited, but includes a cyclobutane ring, cyclopentane ring, cyclohexane ring, cycloheptane ring, cyclooctane ring, norbornane ring, norbornene ring, hydrindane ring, decahydronaphthalene ring, adamantane ring, etc. The thing of carbon numbers 3-30 is mentioned. Preferably carbon number is 3-25. Among these, a cyclohexane ring, a cyclopentane ring, and a norbornane ring are preferable.
Regarding the aromatic ring or aliphatic ring that is ring A or ring B, the position of bonding to Y ¹ , Y ² , or X is not particularly limited.

  Examples of the substituent that the aromatic ring or the aliphatic ring may have include a halogen atom, an alkyl group, an alkoxy group, and a hydroxyl group. Examples of the halogen atom include a fluorine atom, a bromine atom, and a chlorine atom. Examples of the alkyl group include those having 1 to 20 carbon atoms such as a methyl group, an ethyl group, a propyl group, an isopropyl group, a butyl group, and a tertiary butyl group. Examples of the alkoxy group include those having 1 to 20 carbon atoms such as a methoxy group, an ethoxy group, a propoxy group, an isopropoxy group, a butoxy group, and a tertiary butoxy group.

In the formula (2), p and q are each independently an integer of 0 or more, preferably 1 or more, and on the other hand, an integer of 10 or less, preferably 5 or less.
In the formula (2), X is a direct bond, an oxygen atom, a sulfur atom, an alkylene group which may have a substituent, a sulfonyl group, a sulfinyl group, a sulfide group, a carbonyl group, and an aromatic which may have a substituent. Represents a group, —NH—C (═O) —, —NH—, or —O—C _n H _2n —O—. However, n represents an integer of 1 to 5, and neither p nor q is 0.
Among these, a direct bond, an oxygen atom, a sulfur atom, an alkylene group which may have a substituent, a sulfonyl group, a sulfinyl group, a sulfide group, a carbonyl group, an aromatic group which may have a substituent, —NH— or —O—C _n H _2n —O— is preferable, and a direct bond, an oxygen atom, an alkylene group which may have a substituent, a sulfinyl group, or a sulfonyl group is more preferable. Particularly preferred is an atom, an alkylene group which may have a substituent, or a sulfinyl group.

Although there is no special restriction | limiting as an alkylene group, It is preferable that it is a C1-C20 alkylene group, and it is more preferable that it is a C1-C10 alkylene group. Specific examples of the alkylene group include a methylene group, an ethylene group, a propylene group, a butylene group, a pentylene group, a hexylene group, and a 2,2-propanediyl group.
The aromatic group is not particularly limited, and examples thereof include an aromatic hydrocarbon group and an aromatic heterocyclic group. Examples of the aromatic hydrocarbon group include those having 6 to 30 carbon atoms such as a phenylene group, a biphenylene group, a naphthylene group, a phenanthrene group, a triphenylene group, a terphenylene group, a pyrenylene group, and a fluorene group. Examples of the aromatic heterocyclic group include those having 2 to 30 carbon atoms such as a pyridylene group and a quinolylene group. Among these, a phenylene group, a naphthylene group, and a pyridylene group are preferable.

Examples of the substituent that the alkylene group or aromatic group may have include an alkyl group having 1 to 5 carbon atoms, a hydroxy group, an alkoxy group, an amino group, a carboxyl group, and an epoxy group. These substituents may be further substituted with a halogen atom such as a fluorine atom or a chlorine atom.
Y ¹ and Y ² each independently represent a direct bond, an oxygen atom, a sulfur atom, an alkylene group which may have a substituent, a sulfonyl group, a sulfinyl group, a sulfide group, or a carbonyl group. Among these, a direct bond or an oxygen atom is preferable. When p or q is 2 or more, R ¹ includes a plurality of Y ¹ and Y ^2, and the plurality of Y ¹ and Y ² may have the same structure or different structures. There may be. Here, as the alkylene group which may have a substituent, the same groups as those mentioned for X can be used.

It is preferable that the ring A and the ring B have the same structure, and it is also preferable that Y ¹ and Y ² have the same structure.
More preferable examples of R ¹ include those represented by the following general formula (3) or (4).

Equation (3) corresponds to the case where p = 2 and q = 2 in Equation (2). In Formula (3), Ring A, Ring B, Ring C, and Ring D represent the same structure as Ring A and Ring B in Formula (2). Y ¹ , Y ² , Y ³ , and Y ⁴ represent the same structure as Y ¹ and Y ² in Formula (2). Similarly to formula (2), ring A, ring B, ring C and ring D may be different from each other, and Y ¹ , Y ² , Y ³ and Y ⁴ may be different from each other. It is also preferable that the ring A and the ring B have the same structure, and it is also preferable that the ring C and the ring D have the same structure. It is also preferable that Y ¹ and Y ² have the same structure, and it is also preferable that Y ³ and Y ⁴ have the same structure.
In formula (3), ring A, ring B, ring C and ring D are preferably aromatic rings which may have a substituent, and are phenylene groups which may be substituted with a halogen atom. Is more preferable, and a phenylene group is particularly preferable. Y ¹ and Y ² are preferably a direct bond, an oxygen atom, or a sulfur atom. Preferable examples of Y ³ and Y ⁴ include direct bonding.

Equation (4) corresponds to the case where p = 1 and q = 1 in Equation (2). In Formula (4), Ring A and Ring B represent the same structure as Ring A and Ring B in Formula (2). Y ¹ and Y ² represent the same structure as Y ¹ and Y ² in Formula (2). Here, it is also preferable that the ring A and the ring B have the same structure, and it is also preferable that Y ¹ and Y ² have the same structure. In the formula (4), the ring A and the ring B are preferably an aromatic ring which may have a substituent or an aliphatic ring which may have a substituent, and is substituted with a halogen atom. More preferred is a phenylene group, and particularly preferred is a phenylene group. Preferred examples of ^{Y 1} and ^{Y 2} is a direct bond.

Specific examples of R ¹ include structural units of diamine compounds shown below. That is, a divalent substituent obtained by removing two primary amino groups from the diamine compound shown below can be used as R ¹ . Specific examples of such diamine compounds include 1,4-phenylenediamine, 1,2-phenylenediamine, 1,3-phenylenediamine, 4,4′-diaminodiphenyl ether, 3,4′-diaminodiphenyl ether, 1, 4-bis (4-aminophenoxy) benzene, 1,3-bis (4-aminophenoxy) benzene, 2,2-bis (4- (4-aminophenoxy) phenyl) propane, 2,2-bis (4- (4-aminophenoxy) phenyl) hexafluoropropane, bis (4- (4-aminophenoxy) phenyl) sulfone, bis (4- (3-aminophenoxy) phenyl) sulfone, 1,3-bis (4-aminophenoxy) ) Neopentane, 4,4'-diamino-3,3'-dimethylbiphenyl, 4,4'-diamino-2,2'-dimethyl Rubiphenyl, 4,4′-diamino-2,2′-bis (trifluoromethyl) biphenyl, 4,4′-bis (4-aminophenoxy) biphenyl, 4,4′-diamino-3,3′-dihydroxy Biphenyl, bis (4-amino-3-carboxyphenyl) methane, 4,4′-diaminodiphenylsulfone, bis (4- (4-aminophenoxy) phenyl) sulfone, 4,4′-diaminodiphenylsulfide, N- ( 4-aminophenoxy) -4-aminobenzamine, 1,4-diaminocyclohexane, 4,4'-methylenebis (cyclohexylamine), 4,4'-methylenebis (2-methylcyclohexylamine), N- (4-amino Phenyl) -4-aminobenzamide, N, N′-bis (4-aminophanyl) terephthalamide and the like. . Among these, 4,4′-diaminodiphenyl ether, 1,3-bis (4-aminophenoxy) benzene, 2,2-bis (4- (4-aminophenoxy) phenyl) propane, 2,2-bis (4- (4-aminophenoxy) phenyl) hexafluoropropane, bis (4- (4-aminophenoxy) phenyl) sulfone, 4,4′-diamino-3,3′-dimethylbiphenyl or 4,4′-methylenebis (cyclohexylamine) It is preferable to have a divalent substituent obtained by removing an amino group from R) as R ¹ in that the transparency, heat resistance, and mechanical strength of the polyimide resin can be achieved at the same time, more preferably 4, 4′-diaminodiphenyl ether, 2,2-bis (4- (4-aminophenoxy) phenyl) propane, 2,2-bis Divalent compounds obtained by removing amino groups from 4- (4-aminophenoxy) phenyl) hexafluoropropane, bis (4- (4-aminophenoxy) phenyl) sulfone or 4,4′-methylenebis (cyclohexylamine) It is a substituent.

<2.2 Properties of polyimide resin>
The weight average molecular weight (Mw) in terms of polystyrene of the polyimide resin according to the present invention is usually 1.0 × 10 ³ or more, preferably 5.0 × 10 ³ or more, more preferably 1.0 × 10 ⁴ or more. On the other hand, it is usually 1.0 × 10 ⁶ or less, preferably 8.0 × 10 ⁵ or less, more preferably 5.0 × 10 ⁵ or less. This range is preferable in that solubility, solution viscosity, melt viscosity, and the like are in a range that can be easily handled by ordinary production equipment. The weight average molecular weight in terms of polystyrene of the polyimide resin according to the present invention can be determined by gel permeation chromatography (GPC).

The number average molecular weight (Mn) of the polyimide resin according to the present invention is usually 5.0 × 10 ² or more, preferably 2.5 × 10 ³ or more, more preferably 5.0 × 10 ³ or more. On the other hand, it is usually 5.0 × 10 ⁴ or less, preferably 4.0 × 10 ⁴ or less, and more preferably 2.5 × 10 ⁴ or less. This range is preferable in that solubility, solution viscosity, melt viscosity, and the like are in a range that can be easily handled by ordinary production equipment. The number average molecular weight of the polyimide resin according to the present invention can be measured by the same method as the weight average molecular weight.

The molecular weight distribution (PDI, (weight average molecular weight / number average molecular weight (Mw / Mn))) of the polyimide resin according to the present invention is usually 1 or more, preferably 1.1 or more, more preferably 1.2 or more. On the other hand, it is usually 3 or less, preferably 2.8 or less, more preferably 2.5 or less.
It is preferable that the molecular weight distribution is in this range in that a highly uniform solution and molded product can be obtained. The molecular weight distribution of the polyimide resin according to the present invention can be measured by the same method as the weight average molecular weight.

The melt elongation (μm) by thermomechanical analysis (TMA) of the polyimide resin according to the present invention (measurement condition: measurement temperature 270 ° C., tensile load 10 g, holding time 60 minutes, sample shape 4 mm × 5 mm, thickness 45 μm) is usually It is 1.0 × 10 ² or more, preferably 1.0 × 10 ³ or more, more preferably 1.8 × 10 ³ or more. On the other hand, it is usually 1.0 × 10 ⁵ or less, preferably 5.0 × 10 ⁴ or less, more preferably 1.0 × 10 ⁴ or less. By being 1.0 × 10 ² or more, it is preferable in terms of easy melt molding. 1.0 × 10 ⁵ or less is preferable in that sagging during molding is suppressed. The thermomechanical analysis (TMA) of the polyimide resin according to the present invention can be measured by a method described in a known document (Japanese Patent Laid-Open No. 2003-155341).

The concentration of the residual solvent in the polyimide resin according to the present invention is not particularly limited, but is usually 20% by weight or less, preferably 10% by weight or less, more preferably 1% by weight or less, and further preferably 0.5% by weight. % Or less, particularly preferably 0.1% by weight or less. On the other hand, there is no limit on the lower limit. It is preferable to adjust the concentration of the solvent in the polyimide resin within this range because problems such as remarkable foaming at the time of melting described later and generation of flammable gas do not occur.
The density | concentration of the solvent in a polyimide resin can be measured by well-known literature (Unexamined-Japanese-Patent No. 2006-70130).

The concentration of the polyimide resin in the polyimide resin according to the present invention is not particularly limited, but is usually 50% by weight or more, preferably 80% by weight or more, while the upper limit is not limited. By adjusting the concentration of the polyimide resin within this range, foaming and coloring at the time of melting can be suppressed, and good workability can be achieved.
The ratio of the unreacted polyamic acid resin or polyamic acid ester resin to the polyimide resin in the polyimide resin is not particularly limited, but is usually 30% by weight or less, preferably 20% by weight or less, more preferably 10% by weight or less. is there. When 30% or more of the polyamic acid resin or the polyamic acid ester resin is contained in the polyimide resin, the polyimide resin and the polyamic acid resin or the polyamic acid ester resin may be phase-separated to cause white turbidity in the polyimide resin. . Moreover, when the polyimide resin phase-separated inhomogeneously is used for melt molding, the molded body may also be non-uniform and unevenness or white turbidity may occur in the molded body.

The glass transition temperature (Tg) of the polyimide resin by differential scanning calorimetry (DSC method) is usually 150 ° C. or higher, preferably 200 ° C. or higher, more preferably 250 ° C. or higher. A glass transition temperature of 150 ° C. or higher is preferable in that the heat resistance of the polyimide resin molded article obtained in the present invention can be improved.
The coefficient of thermal expansion of the polyimide resin is preferably 100 ppm / K or less, more preferably 70 ppm / K or less in the range of 100 to 200 ° C. A coefficient of thermal expansion in such a range is preferable in that a molded body with high dimensional accuracy can be manufactured.

The polyimide resin obtained in the present invention is transparent, has little coloration, has heat resistance, and can have high mechanical strength. In the present specification, being colorless or transparent means that the transmittance of a light beam at 400 nm is usually 60% or more, preferably 70% or more, particularly preferably 80% or more when formed into a target shape. It means what is. The polyimide resin obtained in the present invention having a high light transmittance is suitably used in a device that requires translucency, such as a photoelectric conversion element. In this specification, the total light transmittance at 400 nm according to JIS K 7361-1 is used as the transmittance.

The yellowness [yellow index (YI)] of the polyimide resin obtained in the present invention when the film thickness is 50 ± 5 μm is usually −10 or more, preferably −5 or more, more preferably −1. That's it. On the other hand, it is usually 20 or less, preferably 15 or less, more preferably 10 or less, and further preferably 5 or less.
Although the polyimide resin obtained in the present invention depends on a molding method for melt molding, it preferably has the following mechanical strength.
The tensile strength of the polyimide resin according to the present invention is not particularly limited, but is usually 50 MPa or more, preferably 70 MPa or more, and is usually 400 MPa or less, preferably 300 MPa or less.
The tensile elastic modulus of the polyimide resin according to the present invention is not particularly limited, but is usually 1000 MPa or more, preferably 1500 MPa, while it is usually 20 Gpa or less, preferably 10 Gpa or less.

The tensile elongation of the polyimide resin according to the present invention is not particularly limited, but is usually 10% GL or more, preferably 20% GL, and is usually 300% GL or less, preferably 200% GL or less. When the polyimide resin has such mechanical strength, a more durable molded body can be obtained.
The polyimide resin according to the present invention preferably has the following melt properties.
The melt viscosity of the polyimide resin is not particularly limited, but is usually 1.0 × 10 ¹ Pa · s or more, preferably 1.0 × 10 ² Pa · s or more at 330 ° C. On the other hand, it is usually 1.0 × 10 ⁷ Pa · s or less, preferably 1.0 × 10 ⁵ Pa · s or less, more preferably 1.0 × 10 ⁴ Pa · s or less, and further preferably 5.0 × 10 ^3. Pa · s or less, particularly preferably 3.0 × 10 ³ Pa · s or less. Polyimide having a melt viscosity of 1.0 × 10 ¹ Pa · s or higher is preferable in that it has high toughness and is suitable for use as a molded product. A polyimide having a melt viscosity of 1.0 × 10 ⁷ Pa · s or less is preferable in that it has good fluidity and is suitable for molding.
The melt viscosity of the polyimide resin obtained in the present invention can be measured by the method of a known document (Japanese Patent Laid-Open No. 1-297427).

Moreover, in order to control the fluidity | liquidity at the time of the polyimide resin melting of the below-mentioned process, the additive may be added to the polyimide resin which concerns on this invention. For example, a coupling agent such as a silane coupling agent or a titanium coupling agent can be added to the polyimide resin according to the present invention.
Examples of the silane coupling agent include γ-aminopropyltriethoxysilane, γ-aminopropyltrimethoxysilane, γ-aminopropyltripropoxysilane, γ-aminopropyltributoxysilane, γ-aminoethyltriethoxysilane, γ -Aminoethyltrimethoxysilane, γ-aminoethyltripropoxysilane, γ-aminoethyltributoxysilane, γ-aminobutyltriethoxysilane, γ-aminobutyltrimethoxysilane, γ-aminobutyltripropoxysilane, and γ- Examples include aminobutyl tributoxysilane.

Examples of the titanium coupling agent include γ-aminopropyltriethoxytitanium, γ-aminopropyltrimethoxytitanium, γ-aminopropyltripropoxytitanium, γ-aminopropyltributoxytitanium, γ-aminoethyltriethoxytitanium, γ -Aminoethyltrimethoxytitanium, gamma-aminoethyltripropoxytitanium, gamma-aminoethyltributoxytitanium, gamma-aminobutyltriethoxytitanium, gamma-aminobutyltrimethoxytitanium, gamma-aminobutyltripropoxytitanium, and gamma- Examples include aminobutyl tributoxy titanium.

The polyimide resin according to the present invention may contain one type of coupling agent or may contain two or more types of coupling agents. The amount of the coupling agent contained in the polyimide resin according to the present invention is preferably 0.1% by mass or more and 3% by mass or less with respect to the polyimide resin from the viewpoint of improving the physical properties of the obtained film.
In addition, if necessary, for example, an inorganic filler or an organic filler such as powder, granule, plate, or fiber can be blended within a range that does not impair the object of the invention.

  Examples of inorganic fillers include oxides such as silica, diatomaceous earth, barium ferrite, beryllium oxide, pumice or pumice balloon; hydroxides such as aluminum hydroxide, magnesium hydroxide or basic magnesium carbonate; calcium carbonate, Carbonates such as magnesium carbonate, dolomite or dosonite; sulfates and sulfites such as calcium sulfate, barium sulfate, ammonium sulfate or calcium sulfite; talc, clay, mica, asbestos, glass fiber, glass balloon, glass beads, calcium silicate, Silicates such as montmorillonite or bentonite; carbons such as carbon fiber, carbon black, graphite or carbon hollow sphere; molybdenum sulfide, zinc borate, barium metaborate, calcium borate, sodium borate or boron Powder-like, granular, plate-like, or fibrous inorganic fillers such as fibers; Powder-like, granular, fibrous, or whisker-like metal fillers such as metal elements, metal compounds, and alloys; silicon carbide, silicon nitride, Examples thereof include powder fillers such as zirconia, aluminum nitride, titanium carbide, and potassium titanate, granular, fibrous, or whisker-like ceramic fillers.

On the other hand, examples of the organic filler include shell fibers such as fir shells, carbon nanotubes, fullerenes, wood flour, cotton, jute, paper strips, cellophane pieces, aromatic polyamide fibers, cellulose fibers, nylon fibers, polyester fibers, Examples thereof include polypropylene fiber, thermosetting resin powder, and rubber.
As a filler, what was processed into flat form, such as a nonwoven fabric, may be used, and a plurality of materials may be mixed and used. Furthermore, if desired, various additives commonly used for resins, such as lubricants, colorants, stabilizers, antioxidants, ultraviolet absorbers, antistatic agents, flame retardants, plasticizers or release agents, You may mix | blend with the polyimide resin which concerns on invention. These various fillers and additive components may be added at any stage of any process for producing the polyimide resin.

[3. Process of melt-molding polyimide resin]
A process for obtaining a polyimide resin molded body by melting and molding the polyimide resin according to the present invention will be described.
First, the process of melting the polyimide resin of the present invention will be described.
The melting temperature is not particularly limited as long as it is equal to or higher than the melting point of the polyimide resin of the present invention, but is preferably performed at a temperature equal to or higher than the melting point and lower than the decomposition temperature of the polyimide resin.

  Further, if desired, inorganic fillers, organic fillers, metal fillers, lubricants, colorants, stabilizers, antioxidants, ultraviolet absorbers, antistatic agents, as long as the object of the present invention is not impaired. A flame retardant, a plasticizer, a mold release agent, etc. can be mix | blended. The polyimide resin of the present invention may be used as a thermoplastic resin, and may be prepared by mixing the above fillers and various additive components used as desired, and kneading with a kneader, or may be prepared in advance with a thermoplastic resin and desired Depending on the conditions, the additive component used may be quantitatively supplied to the extruder and kneaded, and the filler may be prepared by side-feeding and kneading the filler in the melted portion.

Furthermore, you may laminate with the polyimide resin of this invention which softened what processed the filler into flat form, such as a nonwoven fabric. The kneading machine is not particularly limited as long as it can knead the polyimide resin, the filler, and the additive. For example, a screw extruder such as a single-screw extruder or a multi-screw extruder, an elastic extruder, a hydro extruder, or the like. Non-screw extruders such as dynamic extruders, ram-type continuous extruders, roll-type extruders, and gear-type extruders can be exemplified.

Next, the process of shaping the polyimide resin melt will be described. The polyimide resin of the present invention obtained above is an injection molding method, an extrusion molding method, a hollow molding method, a compression molding method, a lamination molding method, a roll processing method, a stretching processing method, a stamp processing method, a hot press method or T-. It is molded into a desired molded product by various molding methods such as a die method. In particular, since the polyimide of the present invention is colorless and transparent, a transparent heat-resistant film can be produced by an extrusion molding method, a lamination molding method, a stretching method, or the like. Further, by using an injection molding method or the like, various molded products such as lenses and light guide plates can be manufactured. The reaction temperature at that time is not particularly limited, but is usually not lower than the glass transition temperature, and is usually not higher than the decomposition temperature.
When molding is performed without using a mold, such as extrusion molding, roll processing method, stretching processing method, etc., the atmosphere may be in the air or in an inert atmosphere, and the pressure may be any of normal pressure, pressurized pressure, or reduced pressure. .

<3.1 Polyimide resin molding>
The polyimide resin molded body obtained by the present invention can produce a three-dimensional molded body such as a sheet having a film thickness of 1 mm or more, a lens, and a light cover that cannot be molded by a general casting method.
Therefore, the polyimide resin molded body obtained by the present invention is excellent in transparency and mechanical properties that cannot be achieved by existing polyimide resins, and has a three-dimensionally complicated shape. In addition, when a film is produced by a general solution casting method, the arrangement of polymer chains and functional groups on the surface of the film differs depending on the presence or absence of contact with the support on the front and back of the film. Contact angle, adhesiveness, surface smoothness, etc.) may be different. However, according to the present invention, there is no time for contact with the support or the like in the heated state, or the time is short, which is preferable in that the difference in performance between the front side and the back side of the film hardly occurs.

Although there is no special restriction | limiting in the density | concentration of the residual solvent in the polyimide resin molding which concerns on this invention, Usually, 10 weight% or less, Preferably it is 5 weight% or less, More preferably, it is 1 weight% or less, More preferably, it is 0.00. It is 5% by weight or less, particularly preferably 0.1% by weight or less. On the other hand, there is no limit on the lower limit. By adjusting the concentration of the solvent in the polyimide resin molded product within this range, it is desirable because adverse effects due to the solvent that volatilizes in subsequent manufacturing processes of electronic devices and the like can be suppressed.
The glass transition temperature (Tg) of the polyimide resin molding according to the present invention by differential scanning calorimetry (DSC method) is usually 170 ° C. or higher, preferably 200 ° C. or higher, more preferably 250 ° C. or higher. It is preferable for the glass transition temperature to be 170 ° C. or higher because it can cope with higher temperature processes in various subsequent electronic device manufacturing processes. The coefficient of thermal expansion of the polyimide resin is usually 70 ppm / K or less, preferably 50 ppm / K or less, more preferably 30 ppm or less, and particularly preferably 20 ppm or less in the range of 100 to 200 ° C. It is desirable that the coefficient of thermal expansion be in such a range because positional deviation, warpage, and the like can be suppressed in subsequent manufacturing processes such as electronic devices.

  The polyimide resin molded body according to the present invention is transparent, has little coloration, has heat resistance, and can have high mechanical strength. When formed into the target shape, the transmittance of light of 400 nm is usually 60% or more, preferably 70% or more, and particularly preferably 80% or more. The light transmittance in such a range is desirable because it does not hinder light emission and absorption in an electronic device using the polyimide resin molded body obtained in the present invention.

The yellowness [yellow index (YI)] of the polyimide resin molded product according to the present invention when the film thickness is 50 ± 5 μm is usually −10 or more, preferably −5 or more, more preferably − 1 or more. On the other hand, it is usually 20 or less, preferably 15 or less, more preferably 10 or less, and further preferably 5 or less. It is desirable that the yellowness is in such a range because it does not hinder light emission and light absorption in an electronic device using the polyimide resin molding obtained in the present invention.

The polyimide resin molded body according to the present invention depends on a molding method for melt molding, but preferably has the following mechanical strength. The tensile strength of the polyimide resin according to the present invention is not particularly limited, but is usually 50 MPa or more, preferably 70 MPa or more, and is usually 400 MPa or less, preferably 300 MPa or less.
The tensile elastic modulus of the polyimide resin according to the present invention is not particularly limited, but is usually 1000 MPa or more, preferably 1500 MPa, while it is usually 20 Gpa or less, preferably 10 Gpa or less.

  The tensile elongation of the polyimide resin according to the present invention is not particularly limited, but is usually 10% GL or more, preferably 20% GL or more, and is usually 400% GL or less, preferably 300% GL or less. . When the polyimide resin molding has such mechanical strength, a more durable electronic device or the like can be obtained.

<3.2 Applications of polyimide resin molding>
The polyimide resin obtained in the present invention can be made into an almost colorless and transparent polyimide resin molded body having various shapes by the above-described various molding methods. As a result, not only film applications, which are typical uses of polyimide resins, but also a wide range of applications are possible. For example, flexible solar cell member, display member, IC packaging tray, IC manufacturing tray, IC socket, wafer carrier, connector, socket, hard disk carrier, liquid crystal display carrier, crystal oscillator manufacturing tray, copier separation claw , Heat insulating bearings for photocopiers, gears for photocopiers, thrust washers, transmission rings, piston rings, oil seal rings, bearing retainers, pump gears, conveyor chains, slide bushes for stretch machines, heat-resistant insulation tape, heat-resistant adhesive tape, high-density magnetic It can be used for production of a recording base, a film for a capacitor or a flexible printed circuit board, and the like. Moreover, it is used also for manufacture of the molded product of the structural member reinforced with glass fiber, carbon fiber, etc., the bobbin of a small coil, or the terminal insulation tube, for example.

  Further, it can be used for the production of laminated materials such as insulating spacers, magnetic head spacers or transformer spacers. Moreover, it can be used for manufacture of enamel coating materials such as electric wire / cable insulation coating materials, low-temperature storage tanks, space insulation materials, and integrated circuits. Furthermore, it can also be used for the production of heat-resistant yarns, woven fabrics or nonwoven fabrics.

Examples The present invention will be described more specifically with reference to the following examples. However, the present invention is not limited to the following examples unless it exceeds the gist.
[Thermomechanical analysis (TMA)]
Using a thermomechanical analyzer (manufactured by SII, TMA / SS6000), sample deformation was measured under measurement conditions 1 and 2, and a softening temperature and a melt elongation were obtained. The deformation start temperature of the test piece under the measurement condition 1 was defined as the softening temperature, and the deformation amount of the sample after 60 minutes under the measurement condition 2 was defined as the melt elongation (μm).
Measurement conditions 1: Measurement temperature range 50 ° C. to 400 ° C. (temperature increase rate: 10 ° C./min), tensile load: 5 g, sample shape 4 mm × 10 mm, thickness 45 μm.
Measurement condition 2: Measurement temperature 270 ° C., tensile load 10 g, holding time 60 minutes, sample shape 4 mm × 5 mm, thickness 45 μm.

[Melting test]
0.1 g of polyimide resin was placed in a fluororesin molding frame, and the polyimide resin was heated and melted at 280 ° C. for about 5 minutes with a heating press (small heating press 180E manufactured by Imoto Seisakusho). Then, it was melt-molded by heating and compressing at 280 ° C. for about 2 minutes at a pressure of 30 MPa. As a result, a case where a molded body having a shape of a forming frame was obtained was marked with ◯, and a case where a molding defect (insufficient flow) was observed was marked with x. In each test, four samples were molded, and the melt moldability was evaluated by the number of samples with a circle.

[Tensile modulus, tensile strength, tensile elongation]
A polyimide resin piece or a polyimide melt-molded product is cut into a strip shape having a width of 5 mm to form a test piece, and a tensile tester (STA-1225, manufactured by Orientec Co., Ltd.) is used, and the tensile speed is 10 mm / min, and the chuck distance is 10 mm. , Measured in a 50% RH environment. The tensile elastic modulus was determined from the initial slope of the stress-strain curve, and the tensile strength and tensile elongation were determined from the maximum stress and elongation.

[Residual solvent amount measurement]
It measured according to the following measurement conditions using the differential thermal-thermogravimetry apparatus (TG / DTA6200 by SII). Measurement conditions: A polyimide resin piece or 20 mg of a polyimide melt-molded product was heated from 40 ° C. to 100 ° C. at a rate of temperature increase of 20 ° C./min, and then allowed to stand at 100 ° C. for 30 minutes. Then, it heated from 100 degreeC to 350 degreeC with the temperature increase rate of 10 degree-C / min, and the weight reduction from 150 degreeC to 300 degreeC was defined as residual solvent content.

[Molecular weight measurement]
The polystyrene equivalent weight average molecular weight of the polyimide resin according to the present invention was determined by gel permeation chromatography (GPC) by the following method. First, GPC of standard polystyrene was measured under the following conditions to prepare a calibration curve. Subsequently, GPC of the sample (polyimide) was measured under the same conditions, and an average molecular weight in terms of polystyrene was obtained.
Measurement condition:
Column: 3 Shodex AD-80M / S Precolumn: 1 Shodex KF-G Solvent: N, N-dimethylformamide (including LiBr 50 mmol / l)
Flow rate: 1.0 ml / min
Temperature: Column 35 ° C
Sample concentration: 0.5% by weight
Detector: UV detector Calibration sample: Monodisperse standard polystyrene [Melt property measurement]
Using a Shimadzu elevated flow tester (manufactured by Shimadzu Corporation, CFT-500A), the flow start temperature and melt viscosity of the polyimide were measured under the following measurement conditions. The temperature at which the molten resin began to flow out of the orifice was defined as the flow start temperature. Further, the temperature at which sufficient melt fluidity (1.0 × 10 ⁵ Pa · s or less) was expressed was defined as the required flow temperature.
Measurement conditions: Measurement temperature range 200 ° C. to 350 ° C. (temperature increase rate: 3 ° C./min) Load 40 kg, internal diameter 2 mm, length 10 mm orifice, sample amount 1.3 grams.

<Synthesis example>
(First Step: Synthesis of 1,1′-bicyclohexane-3,3 ′, 4,4′-tetracarboxylic acid-3,3 ′, 4,4′-dianhydride (H-BPDA))

  150 g of 1,1′-biphenyl-3,3 ′, 4,4′-tetracarboxylic dianhydride (manufactured by Mitsubishi Chemical Corporation) was dissolved in a solution obtained by dissolving 83.3 g of sodium hydroxide in 593 g of water. An aqueous solution of 1,1′-biphenyl-3,3 ′, 4,4′-tetracarboxylic acid tetrasodium salt was prepared, and this salt was nuclear hydrogenated at 10 MPaG and 120 ° C. using a ruthenium / carbon catalyst. Subsequently, 429 g of a 49% sulfuric acid aqueous solution was added dropwise, and the precipitated solid was filtered to obtain 157 g of dicyclohexyl-3,3 ′, 4,4′-tetracarboxylic acid (H-BTC) (yield 81%).

  To a 300 ml three-necked flask equipped with a thermometer, a stirrer, and a Dimroth condenser, 33.7 g (0.98 mol) of the obtained H-BTC and 90 g of acetic anhydride were added under nitrogen. The mixture was heated with stirring and reacted at reflux temperature (130 ° C. to 140 ° C.) for 3 hours. After the reaction, the reaction solution was cooled to 10 ° C., and the solid was filtered to obtain white crystals. The obtained crystals were washed with toluene and dried with a vacuum drier to obtain 1,1′-bicyclohexane-3,3 ′, 4,4′-tetracarboxylic acid-3,3 ′, 4, 23.5 g (yield 78%) of a 4′-dianhydride (H-BPDA) -containing composition was obtained.

(Second step: preparation of polyamic acid ester resin solution)
12.3 g (40.0 mmol) of H-BPDA obtained in the first step was added to 53.4 g of N, N-dimethylacetamide and stirred at room temperature under a nitrogen stream. To this, 0.065 g (2.02 mmol) of methanol and 0.0037 g (0.04 mmol) of dimethylaminoethanol dissolved in 3.0 g of N, N-dimethylacetamide were added and stirred at 70 ° C. for 2 hours. . Thereafter, 4,4′-diaminodiphenyl ether (manufactured by Wako Pure Chemical Industries, Ltd.) dissolved in 23 g of N, N-dimethylacetamide was added, and the mixture was heated and stirred at 70 ° C. for 2 hours and further at 80 ° C. for 4 hours. A polyamic acid ester resin solution was obtained.

<Example 1>
(Step A: Step of obtaining a polyimide resin solution by imidizing a polyamic acid ester resin in the presence of a solvent)
In a four-necked flask equipped with a dry nitrogen gas inlet tube, a condenser, a Dean-Stark agglomerator filled with toluene, and a stirrer, 50 g of the polyamic acid ester resin solution obtained in the synthesis example, 7.5 g of toluene, and 0. 09 g was added. Next, the inside of the three-necked flask was set to a nitrogen atmosphere, the internal temperature was heated to 190 ° C., and water generated accompanying imidization was removed azeotropically with toluene. When heating, refluxing and stirring were continued for 6 hours, generation of water was not observed. Subsequently, heating was performed for 1 hour while removing toluene and triethylamine to obtain a polyimide resin solution.

(Step B: Step of removing the solvent from the polyimide resin solution to obtain a polyimide resin)
The polyimide resin solution obtained in the above step A was dropped into isopropyl alcohol, and the precipitated polyimide resin was collected by filtration and then dried at 80 ° C. under reduced pressure for 3 hours to obtain a polyimide resin solid. 2 g of the resulting polyimide resin solid was added to 8 g of dimethylacetamide (DMAc
) To obtain a polyimide resin solution. The obtained polyimide resin solution was cast on a glass plate with a thickness of 100 μm using a film applicator, and dried at 80 ° C. under reduced pressure for 30 minutes to form a film. Thereafter, it was dried at 230 ° C. for 1 hour and further at 300 ° C. for 1 hour in a nitrogen atmosphere to prepare a polyimide resin film. The obtained polyimide resin film was peeled from the glass plate to obtain a polyimide resin piece. About the obtained polyimide resin piece, it measured as above-mentioned about the measurement of various polyimide resin piece physical properties (Thermomechanical analysis (TMA), tensile elastic modulus, tensile strength, tensile elongation, residual solvent amount). The results are shown in Table 1.
Moreover, the melt-molding test using the obtained polyimide resin piece was done as described above. The results are shown in Table 1.

<Comparative Example 1>
(The process of removing the solvent from the polyamic acid ester resin solution, and then obtaining the polyimide resin by heating polyimide)
The polyamic acid ester resin solution obtained in the synthesis example was cast to a thickness of 100 μm on a glass plate using a film applicator, dried at 80 ° C. for 30 minutes under reduced pressure to form a film, and then 230 ° C. in a nitrogen atmosphere. A polyimide resin film was prepared by heating imidization for 1 hour at 300 ° C. for 1 hour. The obtained polyimide resin film was peeled from the glass plate to obtain a polyimide resin piece. About the obtained polyimide resin piece, it measured as above-mentioned about the measurement of various polyimide resin piece physical properties (Thermomechanical analysis (TMA), tensile elastic modulus, tensile strength, tensile elongation, residual solvent amount). The results are shown in Table 1.
Moreover, the melt-molding test using the obtained polyimide resin piece was done as described above. The results are shown in Table 1.

From the results in Table 1, it can be seen that the polyimide resin of Example 1 was excellent in fluidity at the time of melting and was molded according to the shape of the molding frame. On the other hand, the polyimide resin of Comparative Example 1 was poor in fluidity at the time of melting, many molding defects were observed, and the intended molded article could not be obtained. When the sample was visually observed, many gel components were present in the molded product.
From the above results, it can be seen that according to the method for manufacturing a polyimide resin molded body according to the present invention, a molded body having a desired shape can be manufactured by a process with less load.

<Example 2>
(Process to obtain polyimide resin by removing solvent from polyimide resin solution)
The polyimide resin solution obtained in Example 1 (Step A) was dropped into isopropyl alcohol, and the precipitated polyimide resin was collected by filtration and then dried at 200 ° C. under reduced pressure for 3 hours to obtain a polyimide resin solid. . The melt property measurement was performed with respect to the obtained polyimide resin. The results are shown in Table 2.

(Polyimide resin molding)
0.4 g of the obtained polyimide resin solid is sandwiched between two polyimide films (Kapton manufactured by Toray DuPont), and the polyimide resin is heated and melted at 310 ° C. for about 5 minutes with a heating press (small heating press 180E manufactured by Imoto Seisakusho). did. Then, after heating and compressing at 310 ° C. for about 2 minutes at a pressure of 30 MPa, cooling was performed to obtain a polyimide resin molded body. About the obtained polyimide resin molding, it measured as described above about the measurement of various polyimide resin molding physical properties. The results are shown in Table 2.

<Comparative example 2>
(The process of removing the solvent from the polyamic acid ester resin solution, and then obtaining the polyimide resin by heating polyimide)
The polyamic acid ester resin solution obtained in the synthesis example was cast on a fluororesin tray, dried at 80 ° C. for 30 minutes under reduced pressure, and then heated at 230 ° C. for 1 hour and further at 300 ° C. for 1 hour in a nitrogen atmosphere. A polyimide resin piece was obtained by imidization. Melt property measurement was performed on the obtained polyimide resin piece. The results are shown in Table 2. When 0.5 g of the obtained polyimide resin solid was molded in the same manner as in Example 2, the polyimide resin molded body had a shape necessary for measurement because irregularities were observed on the surface of the molded body due to poor fluidity of the polyimide resin. The measurement was impossible because

From Table 2, it can be seen that the polyimide resin of Example 2 exhibits sufficient fluidity at a practical temperature and is excellent in fluidity at the time of melting. Moreover, it turns out that the polyimide resin molding obtained by thermoplastic molding has sufficient mechanical strength to use for manufacture of an electronic device etc. On the other hand, the polyimide resin of Comparative Example 2 does not melt unless the temperature is raised, and the fluidity at the time of melting is poor.
From the above results, it can be seen that the method for producing a polyimide resin molded body according to the present invention can be used for manufacturing various devices, and a molded body having a desired shape can be manufactured by a process with less load.

Claims (6)

A step of imidizing a polyamic acid resin and / or a polyamic acid ester resin in the presence of a solvent to obtain a polyimide resin solution, a step of removing the solvent from the polyimide resin solution to obtain a polyimide resin, and melt-molding the polyimide resin A process for producing a polyimide resin molded body, wherein the polyimide resin comprises a repeating unit represented by the following general formula (1).

(In formula (1), R ¹ represents a divalent organic group.) R ¹ is represented by the following formula (2), the production method of the polyimide resin molded article according to claim 1.

(In Formula (2), each of ring A and ring B independently represents an aromatic ring which may have a substituent or an aliphatic ring which may have a substituent, and p and q are Each independently represents an integer of 0 to 10. X represents a direct bond, an oxygen atom, a sulfur atom, an alkylene group which may have a substituent, a sulfonyl group, a sulfinyl group, a sulfide group, a carbonyl group, or a substituent. aromatic group which may have a, -NH-C (= O) -, -. NH-, or _{-O-C n H 2n -O- (} n is an integer of from 1 to 5) shows the proviso, p and q are not both 0. Y ¹ and Y ² are each independently a direct bond, an oxygen atom, a sulfur atom, an alkylene group which may have a substituent, a sulfonyl group, a sulfinyl group, when a sulfide group, or .p or q indicates a carbonyl group is two or more, a plurality of Y ^{1, 2,} ring A and ring B each may be different from one another.) X is a direct bond, an oxygen atom, a sulfur atom, an alkylene group which may have a substituent, a sulfonyl group, a sulfinyl group, a sulfide group, a carbonyl group, an aromatic group which may have a substituent, -NH -, or (n 1 to 5 integer) _-O-C n H 2n -O- is, the production method of the polyimide resin molded article according to claim 2. A polyimide resin molded article obtained by melt-molding a polyimide resin containing a repeating unit represented by the following general formula (1).

(In formula (1), R ¹ represents a divalent organic group.) The polyimide resin molded body according to claim 4, wherein R ¹ is represented by the following formula (2).

(In Formula (2), each of ring A and ring B independently represents an aromatic ring which may have a substituent or an aliphatic ring which may have a substituent, and p and q are Each independently represents an integer of 0 to 10. X represents a direct bond, an oxygen atom, a sulfur atom, an alkylene group which may have a substituent, a sulfonyl group, a sulfinyl group, a sulfide group, a carbonyl group, or a substituent. aromatic group which may have a, -NH-C (= O) -, -. NH-, or _{-O-C n H 2n -O- (} n is an integer of from 1 to 5) shows the proviso, p and q are not both 0. Y ¹ and Y ² are each independently a direct bond, an oxygen atom, a sulfur atom, an alkylene group which may have a substituent, a sulfonyl group, a sulfinyl group, when a sulfide group, or .p or q indicates a carbonyl group is two or more, a plurality of Y ^{1, 2,} ring A and ring B each may be different from one another.) X is a direct bond, an oxygen atom, a sulfur atom, an alkylene group which may have a substituent, a sulfonyl group, a sulfinyl group, a sulfide group, a carbonyl group, an aromatic group which may have a substituent, -NH -, or (n 1 to 5 integer) _-O-C n H 2n -O- is, polyimide resin molded article according to claim 5.