WO2005113647A1

WO2005113647A1 - Polyesterimide having low coefficient of linear thermal expansion and precursor therefor

Info

Publication number: WO2005113647A1
Application number: PCT/JP2004/016627
Authority: WO
Inventors: Masatoshi Hasegawa; Shinsuke Inoue
Original assignee: Manac Inc; Masatoshi Hasegawa; Shinsuke Inoue
Priority date: 2004-05-21
Filing date: 2004-11-10
Publication date: 2005-12-01
Also published as: TW200538489A; JPWO2005113647A1; TWI344967B; JP4627297B2

Abstract

A practically useful polyesterimide which has a low permittivity, low coefficient of linear thermal expansion, and high glass transition temperature and has film toughness sufficient in flexible printed wiring boards; a precursor for the polyesterimide; and a process for producing these. The polyesterimide is characterized by containing repeating units represented by the formula (2): wherein A and B each independently represents a divalent aromatic or alicyclic group or a combination of these, provided that in each of A and B, the two bonds linked to the adjacent atoms are in a para arrangement or an arrangement equivalent thereto.

Description

Specification

Polyesterimide having low coefficient of linear thermal expansion and its precursor

Technical field

The present invention relates to a practically useful polyester imide and a precursor thereof, which have a low dielectric constant, a low coefficient of linear thermal expansion, a high glass transition temperature, and a sufficient film toughness for use in a flexible printed wiring board. And their manufacturing methods.

Background art

[0002] Polyimide has not only excellent heat resistance but also properties such as chemical resistance, radiation resistance, electrical insulation, and excellent mechanical properties. Currently, it is widely used in various electronic devices as materials, protective films for semiconductor elements, inter-layer insulating films for integrated circuits, and the like.

[0003] In general, polyimide is prepared by equimolarly dissolving an aromatic tetracarboxylic dianhydride such as pyromellitic anhydride and an aromatic diamine such as diaminodiphenyl ether in an aprotic polar organic solvent such as dimethylacetamide. A polyimide precursor having a high degree of polymerization obtained by the reaction is formed into a film or the like and cured by heating.

[0004] In order to maintain the heat resistance of polyimide while applying force, the skeletal structure must be rigid in molecular design, and as a result, many polyimides are insoluble in organic solvents and even at glass transition temperatures or higher. Since it does not melt, it is usually not easy to mold the polyimide itself.

[0005] Therefore, when forming a polyimide film or the like, usually, a method is used in which a polyimide precursor having high solubility in an amide-based organic solvent is used. Specifically, a polyimide precursor is coated on a metal substrate with a non-tonic organic solvent solution, dried, and heated at 250 ° C to 350 ° C for dehydration ring closure (imidization) to form a polyimide film. I do.

[0006] The thermal stress generated during the process of cooling the polyimide Z metal substrate laminate to the above-described temperature of the imidig temperature to room temperature often causes serious problems such as curling, film peeling, and cracking. Recently, with the increase in the density of electronic circuits, multilayer wiring boards have been adopted.However, even if the film does not peel or crack, residual stress on the multilayer board significantly increases device reliability. Lower. [0007] The stress generated in the imidani process increases as the difference in linear thermal expansion coefficient between the metal substrate and the polyimide film increases, and as the imidani temperature increases.

[0008] As a measure for reducing the thermal stress, there is a method of reducing the thermal expansion of polyimide. Most polyimides have a linear thermal expansion coefficient in the range of 40 to 90 ppm ZK, which is much higher than the linear thermal expansion coefficient of metal substrates such as copper, 17 ppm / K. Research and development on the low thermal expansion polyimide shown below is underway.

[0009] It is generally reported that the low thermal expansion of polyimide is a necessary condition that its main chain structure is linear, its internal rotation is restricted, and its rigidity is rigid (for example, see Non-Patent Document See 1.)). The polyimide obtained from pyromellitic anhydride and diaminodiphenyl ether exhibits high film toughness due to the ether bond present in the main chain, but does not exhibit a low linear thermal expansion coefficient as high as 40 to 50 ppm ZK.

[0010] Among the practically available low thermal expansion polyimide materials, polyimides, which can also form 3,3 ', 4,4'-biphenyltetracarboxylic dianhydride and paraphenylenediamine, are best known. It is known that this polyimide film has a very low linear thermal expansion coefficient of 5-lOppmZK, depending on the film thickness and manufacturing conditions (for example, see Non-Patent Documents 2 and 3).

On the other hand, in recent years, the operation speed of the microprocessor has been increasing, and the shortening of the rise time of the clock signal has become an important issue in the information processing and communication fields. For this reason, it is used as an insulating film. There is an increasing demand for a polyimide film having a low dielectric constant. In addition, high-density wiring and multilayer substrate fabrication for shortening the electrical wiring length are also advantageous in that the lower the dielectric constant of the insulating film, the thinner the insulating layer can be.

[0012] The above polyimide obtained from 3,3 ', 4,4'-biphenyltetracarboxylic dianhydride and paraphenylenediamine exhibits excellent low thermal expansion properties, but has a high dielectric constant of 3.5. Insufficient in terms of electrical conductivity.

[0013] Introduction of a fluorine substituent into the skeleton is effective for lowering the dielectric constant of polyimide (for example, see Non-patent Document 4.) o For example, 2,2 bis (3,4-dicarboxyphene) F) The fluorinated polyimide film obtained from hexafluoropropanoic acid dianhydride and 2,2'bis (trifluoromethyl) benzidine has a very low dielectric constant of 2.65 estimated from the average refractive index. Indicating a value (e.g., Non-Patent Document 5 reference.) ₀

[0014] It is also a low dielectric constant 〖this effective means of reducing the π electrons replacing the aromatic units cycloaliphatic units (e.g., Non-Patent Document 6 reference.) ₀ For example, 1, 2, Non-aromatic polyimide film obtained from 3,4-cyclobutanetetracarboxylic dianhydride and 4,4'-methylenebis (cyclohexylamine) has a very low dielectric constant of 2.6, which is estimated from the average refractive index. indicating a value (e.g., non-Patent Document 7 reference.) ₀

However, a low dielectric constant (a temporary target value of 3.3 or less as a temporary value) and a low coefficient of thermal expansion (30 ppm ZK or less as a temporary target value) at the same time, while maintaining solder heat resistance. Obtaining imide is not easy in molecular design! ヽ. Polymer materials and inorganic materials having a low dielectric constant other than polyimide are also being studied, but the required characteristics are sufficiently satisfied in terms of dielectric constant, coefficient of linear thermal expansion, heat resistance, and film toughness. is there.

In general, the introduction of a fluorine group into a polyimide structure weakens the intermolecular interaction, and tends to hinder the spontaneous molecular orientation during imidization, which is a cause of low thermal expansion. Excessive introduction of fluorine radicals is disadvantageous in terms of cost. As described above, 2,2 bis (3,4-dicarboxyphenol) hexafluoropropanoic acid dianhydride and 2,2'bis (trifluoromethyl) benzidine are the typical fluorinated polyimide films obtained. Although it has a low dielectric constant, it has a very high linear thermal expansion coefficient of 64 ppm ZK and does not exhibit low thermal expansion characteristics (for example, see Non-Patent Document 5).

As described above, introduction of an alicyclic unit into the polyimide skeleton reduces π electrons, and is effective for lowering the dielectric constant. However, the introduction of an alicyclic unit generally has a problem in that the linearity and rigidity of the polyimide main chain skeleton are reduced and the coefficient of linear thermal expansion is increased. For example, when a highly flexible alicyclic diamine such as 4,4'-methylenebis (cyclohexylamine) is used, polymerization proceeds easily with various acid dianhydrides, and a polyimide precursor having a high degree of polymerization is produced. Although produced, the polyimide film obtained by the ring closure reaction does not exhibit low thermal expansion characteristics.

For example, 1,2,3,4-cyclobutanetetracarboxylic dianhydride and 4,4′-methylenebis (cyclohexylamine) force The obtained polyimide film has a low dielectric constant as described above, but has a linear thermal expansion. The coefficient is as high as 70 ppm ZK, and does not show low thermal expansion characteristics.

[0019] On the other hand, while aiming to exhibit low thermal expansion characteristics while maintaining a low dielectric constant, When trans-1,4-cyclohexanediamine, which is a rigid alicyclic diamine, is used instead of diamine, a strong salt is formed during the polymerization of the polyimide precursor, and the polymerization reaction often does not proceed. Occurs.

[0020] For example, 1,2,3,4-cyclobutanetetracarboxylic dianhydride and polyimide having trans 1,4-sixoxyhexandiamine power have a rigid and relatively linear skeleton, and therefore have a low dielectric constant. In addition, the development of low thermal expansion characteristics is expected. However, in practice, it is difficult to polymerize a polyimide precursor for the above reasons.

[0021] In contrast, in the polyimide precursor polymerization reaction of 1,2,3,4-cyclobutanetetracarboxylic dianhydride with 2,2'bis (trifluoromethyl) benzidine, the above-mentioned salt formation is suppressed. It does not occur at all and a high molecular weight product can be easily obtained. Furthermore, the polyimide film has a low dielectric constant (2.66), a low thermal expansion coefficient (21PpmZK) and high glass transition temperature (356 ° C) satisfying simultaneously (e.g., Non-Patent Document 5 reference.) ₀

The only drawback is that the elongation at break of this polyimide film is as low as about 3%, but the film toughness is not so high. This is mainly due to the fact that the structure of the polyimide chain, which is indispensable for the development of a low coefficient of thermal expansion, has a linear and rigid structure, resulting in poor entanglement between polymer chains. This is a problem that is always associated with low thermal expansion polyimides. Polyimides that have a low coefficient of thermal expansion, a low dielectric constant, and a film toughness that is all sufficient to be applied to flexible printed wiring boards have been known.

Non-Patent Document 1: Polymer, 28, 2282 (1987)

Non-Patent Document 2: Macromolecules, 29, 7897 (1996)

(* 3): Polyimiaes: Fundamentals and Applications, Marcel Dekker, New York, 1996, p207)

Non-Patent Document 4: Macromolecules, 24, 5001 (1991)

Non-Patent Document 5: High Performance Polymers, 15, 47 (2003)

Non-Patent Document 6: Macromolecules, 32, 4933 (1999)

Non-Patent Document 7: Reactive and Functional Polymers, 30, 61 (1996)

Disclosure of the invention

Problems the invention is trying to solve The present invention provides a practically useful polyester imide and a precursor thereof, which has a low dielectric constant, a low coefficient of linear thermal expansion, a high glass transition temperature, and also has sufficient film toughness for flexible printed wiring board applications. And a method for producing them.

Means for solving the problem

In view of the above problems, as a result of intensive studies, it has been found that the polyesterimide represented by the formula (2) satisfies the above-mentioned required characteristics, and the present invention has been completed.

That is, the present invention is as follows.

1) Equation (1):

Where:

A and B are each independently a divalent aromatic group, an alicyclic group or a combination thereof. However, the bonding positions of the divalent groups are all in the para-position or a relation equivalent thereto. A polyesterimide precursor comprising a repeating unit represented by the formula:

2) A is

[0030] is selected from a divalent aromatic group or an alicyclic group represented by

[0032] A force selected from a divalent aromatic group or an alicyclic group represented by the following formula. However, the steric structure of the cyclohexane ring in A and B is the chair-type trans configuration described in 1) above. The polyesterimide precursor according to the above.

3) The polyesterimide precursor according to the above 1) or 2), wherein an intrinsic viscosity in N, N-dimethylacetamide at 30 ° C. and a concentration of 0.5% by weight is 0.3 dLZg or more.

4) An organic solvent solution containing the polyesterimide precursor described in 1) to 3) above.

5) Equation (2):

Where

A and B are each independently a divalent aromatic group, an alicyclic group or a combination thereof. However, the bonding positions of the divalent groups are all in the para-position or a relation equivalent thereto. Polyester imide characterized by containing a repeating unit

6) A is

[0035]

[0036] selected from a divalent aromatic group or an alicyclic group represented by

[0038] A force selected from a divalent aromatic group or an alicyclic group represented by the formula: where the steric structure of the cyclohexane ring in A and B is a chair-type trans configuration, as described in 5) above. The polyesterimide as described.

7) A method for producing a polyesterimide film,

(i) preparing an organic solvent solution of the polyesterimide precursor according to 1) to 3) above;

(ii) applying the solution obtained in (i) on a substrate and drying to form a polyesterimide precursor film; and

(iii) The precursor film is subjected to a thermal dehydration cyclization reaction or a cyclization reaction using a dehydration ring closure reagent

And producing a polyesterimide film.

8) A polyesterimide film obtained by the method described in 7) above.

9) The polyesterimide film according to 8) above, which has a dielectric constant lower than 3.3, a linear thermal expansion coefficient lower than 30 ppm ZK, a glass transition temperature of 300 ° C or higher, and sufficient toughness.

10) An electronic device comprising the polyesterimide film described in 8) or 9) above.

Generally, in order for a polymer film to exhibit sufficient film toughness, entanglement between polymer chains is necessary, and the degree of entanglement increases with an increase in the degree of polymerization of the polymer. Also, if the main chain does not include any internally rotatable bending bonds even if it has a high molecular weight, the polymer chains cannot be entangled and the membrane becomes fragile. Polyimide skeleton Introducing an ether bond into the polymer has a great effect on improving the film toughness. On the other hand, it reduces the rigidity and linearity of the main chain and hinders the development of low thermal expansion characteristics.

In order to achieve both low thermal expansion characteristics and film toughness, the present invention focused on ester bonds.

Ester bonds are relatively hindered from conformational changes, where the internal rotation barrier is higher than ether bonds, and are expected to provide some degree of flexibility to the main chain.

[0041] Further, since the ester bond has a lower polarizability per unit volume than the amide bond or the imide bond, introduction of the ester bond into the polyimide is also advantageous for low dielectric constant. Generally, ester groups are expected to contribute to a decrease in water absorption, which largely affects the dielectric constant, in view of the fact that polyesters exhibit lower water absorption than polyimide / polyamide.

[0042] The tetracarboxylic dianhydride monomer used in the production of the polyesterimide of the present invention can be easily synthesized from a diol imparting rigidity or linearity such as hydroquinone and trimellitic anhydride chloride. And the resulting monomer is also of high purity. In addition, the raw materials used can be obtained at low cost, which is advantageous in terms of the production cost of polyesterimide. Brief Description of Drawings

FIG. 1 is an infrared absorption spectrum of the ester group-containing tetracarboxylic dianhydride described in Example 1.

FIG. 2 is an infrared absorption spectrum of the ester group-containing tetracarboxylic dianhydride described in Example 2.

FIG. 3 is an infrared absorption spectrum of the polyesterimide precursor film described in Example 3.

FIG. 4 is an infrared absorption spectrum of the polyesterimide film described in Example 3.

FIG. 5 is an infrared absorption spectrum of the polyesterimide precursor film described in Example 4.

FIG. 6 is an infrared absorption spectrum of the polyesterimide film described in Example 4.

FIG. 7 is an infrared absorption spectrum of the polyesterimide precursor film described in Example 5.

FIG. 8 is an infrared absorption spectrum of the polyesterimide film described in Example 5. BEST MODE FOR CARRYING OUT THE INVENTION

Hereinafter, the present invention will be described in detail.

The synthesis of the tetracarboxylic dianhydride monomer represented by the formula (3) is performed as follows. First, a diol is dissolved in a dehydrated organic solvent such as tetrahydrofuran or N, N-dimethylformamide, and a tertiary amine such as pyridine / triethylamine is added as a deoxidizing agent. To this solution, a solution of trimellitic anhydride chloride in a molar amount twice as much as that of the diol used was gradually added dropwise while cooling with ice, and the mixture was stirred at room temperature for 24 hours to obtain the desired formula (3):

[0047] In the formula, A is a divalent aromatic group, an alicyclic group or a combination thereof, provided that the bonding positions of the divalent groups are all in the para-position or a relation equivalent thereto. The tetracarboxylic dianhydride monomer represented can be obtained. After completion of the reaction, the tertiary amine hydrochloride contained in the above reaction solution is removed by filtration, the reaction solvent is distilled off under reduced pressure, and recrystallization is repeated using an appropriate solvent to obtain a high-molecular-weight polymer that can be used for polymerization. A pure ester group-containing acid dianhydride monomer is obtained.

[0048] To remove the hydrochloride component more strictly, the product is dissolved in chloroform and ethyl acetate, and the mixture is shaken with water to extract and remove the hydrochloride salt. Alternatively, drop the reaction solution into a large amount of water and wash the precipitated product. Since the anhydride groups are partially hydrolyzed by these operations, they are subjected to thermal ring closure at 200 ° C. in vacuum, and finally recrystallized from an appropriate solvent.

[0049] Ring closure treatment of the ester group-containing tetracarboxylic dianhydride monomer can also be performed by dissolving in a dehydrating agent such as acetic anhydride and heating and refluxing it. When used for applications, it is preferable to thermally close the ring.

[0050] Preferable to satisfy the required properties of the polyesterimide according to the present invention! / ヽ diol is an aromatic or Z or alicyclic dihydroxy compound having two hydroxy groups at each terminal. However, in these compounds, the bonding positions of the hydroxy group, the aromatic group, and the z or alicyclic group are all related to the para-position or a position corresponding thereto. In charge.

[0051] In the present invention, the "para position or a relation corresponding thereto" means a relation such that one bonding position is point-symmetric or line-symmetric with respect to the other bonding position. For example, a 6-membered ring such as benzene and cyclohexane means 1,4, and a 10-membered ring such as a naphthalene ring means 2,6 or 1,5. (Although the number representing the substitution position may vary depending on the precedence in the nomenclature, the relationship between the two is maintained irrespective of the number.) The diol of the present invention is in the para-position or By having a corresponding relationship, a straight and rigid structure is provided.

[0052] Preferred aromatic dihydroxy conjugates include, specifically, monocyclic and condensed polycyclic carbons having 6 to 24 carbon atoms and having two hydroxyl groups in a para position or a relationship corresponding thereto. Hydrogen groups, which may optionally be interconnected directly or by a bridging member (in which case, the two hydroxyl groups are each terminally present). Here, the bridging member is a spacer group having 116 atoms, and may be, for example, alkylene, ONH—, carbonyl, sulfiel, sulfol, or a combination thereof. Further, they may be optionally substituted by one or more halogen, hydroxyl, or alkyl having 14 to 14 carbons, alkyl or alkoxy.

[0053] More preferable aromatic dihydroxy conjugates include, for example, hydroquinone, 4,4'-biphenol, and 4, A "-dihydroxy-terphenyl.

Preferred alicyclic dihydroxy conjugates are, specifically, monocyclic or polycyclic carbons having 6 to 24 carbon atoms having two hydroxyl groups in para-position or a relationship corresponding thereto. Hydrogen groups, which may optionally be interconnected directly or by a bridging member (in which case, the two hydroxyl groups are each terminally present). Here, the bridging member is a spacer group having 116 atoms, and may be, for example, alkylene, ONH—, carbol, sulfiel, sulfol, or a combination thereof. In addition, they may be optionally substituted by one or more halogen, hydroxyl, or alkyl having 1 to 14 carbon atoms, alkyl or alkoxy, and / or one or more of O NH—, It is interrupted by Carbol, Sulfiel, or Sulfol. [0055] More preferred alicyclic dihydroxy conjugates include, for example, trans 1,4-cyclohexanediol.

Subsequently, the polymerization of the polyesterimide precursor is performed as follows. First, a diamine component is dissolved in a polymerization solvent, and a tetracarboxylic dianhydride powder represented by the formula (3) is gradually added thereto. Using a mechanical stirrer, 10 to 40 ° C, preferably Stir at room temperature for 0.5-48 hours. At this time, the monomer concentration is 5 to 40% by weight, preferably 10 to 35% by weight. By performing polymerization in this monomer concentration range, a uniform and high polymerization degree polyesterimide precursor solution can be obtained.

The polyesterimide precursor of the present invention has an intrinsic viscosity of 0.3 dL / g or more measured in N, N-dimethylacetamide at 30 ° C. at a concentration of 0.5% by weight, and It is preferably in the range of 0.3-6. OdL / g, depending on the desired use of OdL / g.

[0058] Since the polyesterimide precursor having a higher degree of polymerization tends to be obtained as the monomer concentration is higher, it is preferable to start the polymerization at the highest possible concentration, particularly for applications where the polyesterimide film requires high toughness. . In this polymerization reaction, the molar ratio between the acid dianhydride component and the diamine component is preferably such that the acid dianhydride component and the diamine component = 0.7 to 1.3. 1. 05 range power preferred! / ヽ.

[0059] As the polymerization solvent, N, N-dimethylacetamide, N, N-getylacetamide, N, N-dimethylformamide, N-methyl-2-pyrrolidone, hexamethylphosphoramide, dimethylenoles Norefoxide, γ-butyrolataton, 1,3 dimethyl-2 imidazolidinone, 1,2 dimethoxetane bis (2-methoxyethyl) ether, terahydrofuran, 1,4 dioxane, picoline, pyridine, acetone, chloroform, toluene, Aprotic solvents such as xylene, and protic solvents such as phenol, ο-cresol, m-cresol, p-cresol, o-chlorophenol, _m- chlorophenol, and p-chlorophenol can be used. These solvents may be used alone or in combination of two or more.

[0060] Preferable to satisfy the required properties of the polyesterimide according to the present invention! / Diamine component is an aromatic and Z or alicyclic diamine compound having two amino groups at the respective terminals. However, in these compounds, the bonding positions of the amino group, the aromatic group and the Z or alicyclic group are all in the para-position or a relation equivalent thereto. Book The diamine component of the invention has a linear or rigid structure by having a para-position or a relation equivalent thereto.

[0061] Preferred diamine components are p-phenylenediamine, benzidine, 4,4 'diaminobenzalide, 1,4 diaminocyclohexane or 4-aminobenzoic acid ^ aminophenol, which may be one in some cases. It may be substituted with the above halogen, hydroxyl, or alkyl having 14 to 14 carbon atoms, alkyl halide or alkoxy. Specifically, 2-methyl-1,4-phenylenediamine, 2-trifluoromethyl-1,4-phenylenediamine, benzidine, o-tolidine, m-trizine, 2,2'bis (trifluoromethyl) benzene Gin, 3,3'-dihydroxybenzidine, 3,3'-dimethoxybenzidine, 4,4'diaminobenzalide, trans 1,4 diaminocyclohexane or 4-aminobenzoic acid 4'-aminophenol are preferred, for example. No. In the polyesterimide according to the present invention, it is preferable to use these diamine components in an amount of 70 to 100% by mole of the diamine components used.

[0062] The aromatic diamine which can be partially used in the range without significantly impairing the required properties of the polyesterimide according to the present invention is not particularly limited, but m-phenylenediamine, 2,4-diaminotoluene, 2,4 -Diaminoxylene, 2,4-diaminodulene, 4,4'-Diaminodiphenylmethane, 4,4'-Methylenebis (2-methyla-line), 4,4'-Methylenebis (2-ethyla-line), 4,4'-Methylenebis ( 2, 6-dimethyla-phosphine), 4, 4'-methylene bis (2,6-diethyl aniline), 4, 4'-diaminodiphenyl ether, 3, 4'-diaminodidiphenyl ether, 3, 3'-diaminodiphenyl- Diether, 2, 4 '-diaminodiphenyl-ether, 4, 4' diaminodiphenylsulfone, 3, 3 '-diaminodiphenyl-sulfone, 4, 4'-diaminobenzophenone, 3, 3 ' Aminobenzophenone, 1,4-bis (4-aminophenoxy) benzene, 1,3-bis (4-aminophenoxy) benzene, 1,3-bis (3-aminophenoxy) benzene, 4,4'bis (4-aminophenoxy) biphenyl, bis (4- (3-aminophenoxy) phenyl) sulfone, bis (4- (4-aminophenoxy) phenyl) sulfone, 2,2-bis (4- (4aminophenyloxy) phenyl) propane, 2, Examples thereof include 2-bis (4- (4-aminophosphenoxy) phenyl) hexafluoropropane, 2,2bis (4-aminophenyl) hexafluoropropane, and p-terphenylenediamine. Also these Can be used in combination of two or more.

[0063] The aliphatic diamine that can be partially used within a range that does not significantly impair the required properties of the polyesterimide is not particularly limited, but cis 1,4-diaminocyclohexane, 1,4-diaminocyclohexane (trans / cis Mixture), 1,3-diaminocyclohexane, isophoronediamine, 1,4-cyclohexanebis (methylamine), 2,5 bis (aminomethyl) bicyclo [2.2.1] heptane, 2,6-bis (Aminomethyl) bicyclo [2.2.1] heptane, 3,8 bis (aminomethyl) tricyclo [5.2.1.0] decane, 1,3-diaminoadamantane, 4,4'-methylenebis (cyclohexylamine ), 4,4'-methylenebis (2-methylcyclohexylamine), 4,4'-methylenebis (2-ethylcyclohexylamine), 4,4'-methylenebis (2,6-dimethyl) Lecyclohexylamine), 4,4'-methylenebis (2,6-getyl cyclohexylamine), 2,2-bis (4-aminocyclohexyl) propane, 2,2bis (4aminocyclohexyl) hexaflu Olopropane, 1,3 propanediamine, 1,4-tetramethylenediamine, 1,5 pentamethylenediamine, 1,6-hexamethylenediamine, 1,7 heptamethylenediamine, 1,8 And rangenamine and 1,9 nonamethylenediamine. Two or more of these can be used in combination.

In order to maintain high thermal stability and high glass transition temperature, it is preferable to use an alicyclic diamine such as 1,4 diaminocyclohexane as the aliphatic diamine.

[0065] In general, when an aliphatic diamine is subjected to a polymerization reaction of a polyesterimide precursor, a salt is formed at an early stage of the polymerization, which may hinder the progress of the polymerization. Among the aliphatic diamines, especially with the combination of trans 1,4-diaminocyclohexane and most of the tetracarboxylic dianhydrides, stronger salts are formed and often the polymerization does not proceed at all!

When the tetracarboxylic dianhydride represented by the formula (3) according to the present invention is used while reacting, it quickly reacts with trans 1,4-diaminocyclohexane to give a high polymerization degree. A polyesterimide precursor can be easily obtained. Therefore, there is no need for a complicated pre-polymerization treatment step for silylizing aliphatic diamine with a silylating agent such as chlorotrimethylsilane.

Further, in order to exhibit a low dielectric constant and a low coefficient of linear thermal expansion and to reduce the water absorption, a diamine containing an ester bond such as 4-aminobenzoic acid 4′-aminophenol is used as the aromatic diamine. It is also preferable to use the

[0068] An acid dianhydride component other than the tetracarboxylic dianhydride represented by the formula (3) is partially added to the polyesterimide according to the present invention in a range not significantly impairing the required properties and polymerization reactivity. Can be used for The copolymeric dianhydride component is not particularly limited, but may be pyromellitic dianhydride, 3,3 ', 4,4'-biphenyltetracarboxylic dianhydride, 3,3', 4,4 ' Benzophenone tetracarboxylic dianhydride, 3, 3 ', 4, 4'-biphenyl ether tetracarboxylic dianhydride, 3, 3', 4, 4'-biphenyl sulfone tetracarboxylic dianhydride 2,2'bis (3,4-dicarboxyphenyl) hexafluoropropanoic dianhydride, 2,2'bis (3,4-dicarboxyphenyl) propanoic dianhydride, Examples include 1,4,5,8-naphthalenetetracarboxylic dianhydride. These may be used alone or in combination of two or more as copolymer components.

[0069] A polymer dissolution promoter often added during the polymerization of the polyesterimide precursor, that is, a metal salt such as lithium bromide / lithium chloride, need not be used at all in the polyesterimide precursor polymerization reaction according to the present invention. ,. These metal salts should not be used because even if trace amounts of metal ions remain in the polyesterimide film, the reliability as an electronic device is significantly reduced.

[0070] The polyesterimide precursor solution applied on the substrate is dried in a range of 40 ° C to 180 ° C. The obtained polyesterimide precursor film is heat-treated on a substrate in air, in an atmosphere of an inert gas such as nitrogen, or in a vacuum, at a temperature of 200 ° C to 430 ° C, preferably 250 ° C to 400 ° C. Thus, a polyesterimide film is obtained.

[0071] Imido-dani can also be performed chemically using a dehydration cyclization reagent. That is, a polyesterimide film can also be obtained by immersing the polyesterimide precursor film formed on the substrate in acetic anhydride containing a basic catalyst such as pyridine or triethylamine at room temperature for one minute and several hours.

[0072] In the obtained polyesterimide film, additives such as an acid stabilizer, a terminal blocking agent, a filler, a silane coupling agent, a photosensitizer, a photopolymerization initiator, and a sensitizer may be added, if necessary. May be mixed.

Example [0073] Hereinafter, the present invention will be described specifically with reference to Examples, but the present invention is not limited thereto. In addition, the analytical value in each example was calculated | required by the following method.

[0074] 贿

A 0.5% by weight solution of the polyesterimide precursor in N, N-dimethylacetamide was measured at 30 ° C. using an Ostwald viscometer.

[0075] Glass transition temperature

The dynamic viscoelasticity was measured from the loss peak at a frequency of 0.1Ηζ and a heating rate of 5 ° CZ.

[0076] 5. / o weight loss temperature

The thermogravimetric change of the polyesterimide film was measured at a heating rate of 10 ° CZ, and the temperature at which the weight was reduced by 5% was determined.

[0077] Linear heat coefficient

From the thermomechanical analysis, the coefficient of linear thermal expansion was determined as the average value in the range of 100 to 200 ° C from the elongation of the test piece at a load of 0.5 gZ, a film thickness of 1 μm, and a heating rate of 5 ° CZ.

[0078] Birefringence

Abbe refraction of the refractive index in the direction ( _n ) parallel to the polyesterimide film ( _n ) and the direction ( _n ) perpendicular to the polyesterimide film

m out

Using a measuring thorium lamp, the wavelength is 589, and determine the birefringence (Δη = η−η) from the difference between these refractive indices.

in out

[0079] Invitation rate, invitation tangent

The dielectric constant and the dielectric loss tangent were measured by preparing an electrode pattern by depositing gold on a polyesterimide film cut into a circular shape with a diameter of 5 cm, and sandwiching it with a dielectric measurement electrode 16451B manufactured by Agilent Technologies, Inc. The measurement was performed at a relative humidity of 46% by connecting to a high-precision LCR meter 4285A manufactured by Technology One.

Further, based on the average refractive index of the polyesterimide film [n = (2n + n) Z3], the following formula

av m out

Calculated the dielectric constant (ε) at 1 MHz. ε = 1.Ι Χ η ²

av

[0080] Water absorption

The polyesterimide film was vacuum-dried at 50 ° C for 24 hours, immersed in water at 25 ° C for 24 hours, and calculated as an increase in weight after wiping off excess water. [0081] Mechanical Special

The Young's modulus, breaking strength and breaking elongation of the polyesterimide film were determined by performing a tensile test on a 30 mm × 3 mm test piece using Tensilon manufactured by Toyo Baldwin Co. at a tensile speed of 8 mmZ.

Synthesis of Tetracarboxylic Dianhydride Containing Ester

(Example 1)

In a well-dried three-necked flask equipped with a stirrer, 20 mmol (3.7240 g) of 4, A'-biphenol is dissolved in a mixed solvent of 22 mL of anhydrous N, N-dimethylformamide and 200 mmol (16 mL) of anhydrous pyridine, and the reaction vessel is closed with a septum cap. Sealed. While cooling in an ice bath, a solution of trimellitic anhydride chloride (40 mmol, 8.4221 g) in anhydrous N, N-dimethylformamide (51 mL) was slowly added dropwise to this solution with a syringe, and the mixture was further stirred at room temperature for several hours. did. After the completion of the reaction, the reaction solution was concentrated by an evaporator and dropped into water to obtain a precipitate. As a result, the ring is partially hydrolyzed and the ring is opened.The crude product obtained for ring closing is vacuum-dried at 200 ° C for 24 hours. It was recrystallized from (volume ratio 8Z2). The crystals separated by filtration were further dried in vacuum at 200 ° C. for 24 hours. From the infrared absorption spectrum (FIG. 1), it was confirmed that the target tetracarboxylic dianhydride was obtained, and that the thermal ring closure was completely performed.

(Example 2)

In a well-dried three-necked flask equipped with a stirrer, 20 mmol (2.221 g) of hydroquinone was dissolved in a mixed solvent of 50 mL of anhydrous N, N-dimethylformamide and 200 mmol (16 mL) of anhydrous pyridine, and the reaction vessel was sealed with a septum cap. While cooling in an ice bath, a solution of trimellitic anhydride chloride 40 mmol (8.4221 g) in anhydrous N, N-dimethylformamide (51 mL) was slowly added dropwise to this solution with a syringe, and the mixture was further added at room temperature for several hours. Stirred. After completion of the reaction, the reaction solution was concentrated by an evaporator and dropped into water to obtain a precipitate. Since the ring was opened by partial hydrolysis, the crude product obtained for ring closing was vacuum-dried at 200 ° C for 24 hours and recrystallized from 1,4-dioxane. The crystals separated by filtration were further dried in vacuum at 200 ° C. for 24 hours. From the infrared absorption spectrum (FIG. 2), it was confirmed that the desired tetracarboxylic dianhydride was obtained and that the thermal ring closure was completely performed. [0084] Polymerization, imidization of polyesterimide precursor and evaluation of polyesterimide film properties (Example 3)

0814 g) was placed in a well-dried sealed reaction vessel equipped with a stirrer, and dissolved in 15 mL of N, N-dimethylacetamide sufficiently dehydrated with Molecular Sieves 4A. 10 mmol (5.3439 g) of the tetracarboxylic dianhydride powder described in 1 was gradually added. Five minutes later, 1 lmL of the solvent was diluted with kamitol because the solution viscosity increased rapidly. The mixture was further stirred at room temperature for 24 hours to obtain a transparent, uniform and viscous polyesterimide precursor solution.

[0085] The polyesterimide precursor solution did not precipitate or gel at all even when left at room temperature and 20 ° C for one month, and showed extremely high solution storage stability. The intrinsic viscosity of the polyesterimide precursor measured with an Ostwald viscometer in N, N-dimethylacetamide at 30 ° C. at a concentration of 0.5% by weight was 1.12 dLZg.

[0086] The polyesterimide precursor solution was applied to a glass substrate, and dried at 60 ° C for 2 hours. The resulting polyesterimide precursor film was thermally imidized on the substrate at 250 ° C under reduced pressure for 2 hours. After that, the substrate force was removed to remove residual stress, and heat treatment was further performed at 350 ° C for 1 hour to obtain a transparent polyesterimide film having a thickness of 20 m.

[0087] The polyesterimide film did not break even in the 180 ° bending test, and showed toughness.

In addition, the polymer did not show any solubility in any organic solvent. As a result of dynamic viscoelasticity measurement of this polyesterimide film, no clear glass transition point (determined from the loss peak in the dynamic viscoelasticity curve) was observed, and a force showing no thermoplasticity was observed. . This shows that this polyesterimide film is extremely high and has dimensional stability. The coefficient of linear thermal expansion showed a very low coefficient of linear thermal expansion of 7.4 ppm ZK. This is considered to be due to a high degree of in-plane orientation of the polyesterimide chain, judging also a very large birefringence value (Δη = 0.187). The dielectric constant estimated from the average refractive index is 3.26, a typical wholly aromatic low thermal expansion polyesterimide composed of 3,3 ', 4,4'-biphenyltetracarboxylic dianhydride and ρ-phenylenediamine. It was lower than the dielectric constant (3.5). This result is the effect of introducing an ester group into the polyesterimide skeleton. The 5% weight loss temperature was 470 ° C in nitrogen and 463 ° C in air. Thus this Polyester Luimide exhibited a very low coefficient of linear thermal expansion, excellent dimensional stability, high thermal stability, and sufficient film toughness. The infrared absorption spectra of the obtained polyesterimide precursor film and polyesterimide film are shown in FIGS. 3 and 4, respectively.

(Example 4)

0814 g) of P-phenylenediamine (OmmoKl. 0814 g) was placed in a well-dried sealed reaction vessel equipped with a stirrer, and dissolved in 15 mL of N, N-dimethylacetamide thoroughly dehydrated with Molecular Sieves 4A. 10 mmol (4.5828 g) of the tetracarboxylic dianhydride powder described in Example 2 was gradually added. Since the solution viscosity increased rapidly, 52 mL of the mixture was diluted with a suitable solvent, and one hour later, 52 mL of the solution was diluted. The mixture was further stirred at room temperature for 24 hours to obtain a transparent, uniform and viscous polyesterimide precursor solution.

[0089] Even if this polyesterimide precursor solution was left at room temperature and 20 ° C for one month, no precipitation or gelation occurred, and extremely high solution storage stability was exhibited. The intrinsic viscosity of the polyesterimide precursor measured with an Ostwald viscometer at 30 ° C and 0.5% by weight in N, N dimethylacetamide was 5.19 dLZg, and an extremely high molecular weight product was obtained.

[0090] The polyesterimide precursor solution was applied to a glass substrate, and dried at 60 ° C for 2 hours. A polyesterimide precursor film obtained was thermally imidized on the substrate at 250 ° C under reduced pressure for 2 hours. After that, the substrate force was removed to remove residual stress, and heat treatment was further performed at 350 ° C for 1 hour to obtain a transparent polyesterimide film having a thickness of 20 m.

[0091] The polyesterimide film did not break even in the 180 ° bending test, and showed toughness.

In addition, the polymer did not show any solubility in any organic solvent. As a result of dynamic viscoelasticity measurement of this polyesterimide film, no clear glass transition point (determined from the loss peak in the dynamic viscoelasticity curve) was observed, and a force showing no thermoplasticity was observed. . This shows that this polyesterimide film is extremely high and has dimensional stability. The coefficient of linear thermal expansion was 3.2 ppmZK, which was as low as silicon. Judging from the extremely large birefringence value (Δη = 0.219), this is thought to be due to the high degree of in-plane orientation of the polyesterimide chains. The dielectric constant estimated from the average refractive index is 3.22, a semi-aromatic low thermal expansion polyester which has 3,3 ', 4,4'-biphenyltetracarboxylic dianhydride and 1,4-cyclohexanediamine. Comparable with the dielectric constant of imide (3.15) Value. The 5% weight loss temperature was 481 ° C in nitrogen and 463 ° C in air. Thus, the polyesterimide exhibited a coefficient of linear thermal expansion as low as silicon, excellent dimensional stability, high thermal stability, and sufficient film toughness. The infrared absorption spectra of the obtained polyesterimide precursor film and polyesterimide film are shown in FIGS. 5 and 6, respectively.

(Example 5)

According to the method described in Example 4, polymerization was conducted from 2,2′bis (trifluoromethyl) benzidine and the tetracarboxylic dianhydride described in Example 2 to obtain a transparent, uniform and viscous polyesterimide precursor. A body solution was obtained.

[0093] The polyesterimide precursor solution did not precipitate or gel at all even when left at room temperature and 20 ° C for one month, and showed extremely high solution storage stability. The intrinsic viscosity of the polyesterimide precursor measured with an Ostwald viscometer at 30 ° C. and 0.5% by weight in N, N-dimethylacetamide was 2.93 dLZg, which was an extremely high molecular weight substance.

[0094] This polyesterimide precursor solution was applied to a glass substrate, and dried at 60 ° C for 2 hours. The resulting polyesterimide precursor film was thermally imidized on the substrate at 250 ° C under reduced pressure for 2 hours. After that, the substrate force was removed to remove residual stress, and heat treatment was further performed at 350 ° C for 1 hour to obtain a transparent polyesterimide film having a thickness of 20 m.

[0095] The polyesterimide film did not break even in the 180 ° bending test, and showed toughness.

As a result of dynamic viscoelasticity measurement of this polyesterimide film, the glass transition temperature was 360 ° C or higher. The coefficient of linear thermal expansion was relatively low at 30 ppm ZK, indicating a linear coefficient of thermal expansion. Judging from the large birefringence value (Δη = 0.135), this is considered to be due to the in-plane orientation of the polyesterimide chains. The dielectric constant estimated from the average refractive index was relatively low at 2.99. The 5% weight loss temperature was 487 ° C in nitrogen and 479 ° C in air. Thus, the polyesterimide exhibited relatively low coefficient of linear thermal expansion, high glass transition temperature, relatively low dielectric constant, high thermal stability, and good film toughness. FIGS. 7 and 8 show infrared absorption spectra of the obtained polyesterimide precursor film and polyesterimide film, respectively.

[0096] (Example 6) According to the method described in Example 4, polymerization was carried out from trans 1,4-diaminocyclohexane and the tetracarboxylic dianhydride described in Example 2. Although a salt was formed in the early stage of the polymerization, the salt was not so strong and was gradually dissolved by stirring, and after 24 hours, a clear, uniform and viscous polyesterimide precursor solution was obtained. This polyesterimide precursor solution did not precipitate or gel at all even when left at room temperature and 20 ° C. for one month, and showed extremely high solution storage stability. The intrinsic viscosity of the polyesterimide precursor measured in an N, N-dimethylacetamide at 30 ° C. and a concentration of 0.5% by weight with an Ostwald viscometer was 0.52 dLZg. Casting and thermal imidation were performed according to the method described in Example 4 to obtain a polyesterimide film having high transparency.

(Example 7)

According to the method described in Example 4 except that N-methyl-2-pyrrolidone was used instead of N, N-dimethylacetamidoamide as the polymerization solvent, trans 1,4-diaminocyclohexane and described in Example 2 were used. Was polymerized from tetracarboxylic dianhydride. The strength of the salt formed at the beginning of the polymerization was not so strong, but gradually dissolved by stirring, and after 20 hours, a transparent, uniform and viscous polyesterimide precursor solution was obtained.

[0098] The polyesterimide precursor solution did not precipitate or gel at all even when left at room temperature and 20 ° C for one month, and showed extremely high solution storage stability. The intrinsic viscosity of the polyester imide precursor measured with an Ostwald viscometer at 30 ° C. and 0.5% by weight in N, N dimethylacetamide was 1.14 dLZg, which was a high molecular weight product.

[0099] The polyesterimide precursor solution was applied to a glass substrate and dried at 60 ° C for 2 hours. The obtained polyesterimide precursor film was placed on the substrate at 250 ° C under reduced pressure for 1 hour and further at 300 ° C. After performing thermal imidation for 1 hour, the substrate was peeled off to remove residual stress, and heat treatment was further performed at 350 ° C for 1 hour to obtain a highly transparent polyesterimide film having a thickness of 20 m.

[0100] The polyesterimide film did not break even in the 180 ° bending test, and showed toughness.

As a result of dynamic viscoelasticity measurement of this polyesterimide film, no clear glass transition point was observed, and the film showed no thermoplasticity at all. This indicates that the polyesterimide film is extremely high and has dimensional stability. The linear thermal expansion coefficient is 13ppm It showed ZK and very low linear thermal expansion coefficient. Judging from the large birefringence value (Δη = 0.135), this is considered to be due to the in-plane orientation of the polyesterimide chain. The dielectric constant estimated from the average refractive index was relatively low at 3.04. As for mechanical properties, the Young's modulus was 5.6 GPa, the breaking strength was 0.18 GPa, indicating high elasticity and high strength, and the breaking elongation was 4.1%. The 5% weight loss temperature was 471 ° C in nitrogen and 428 ° C in air. Thus, the polyesterimide exhibited a low coefficient of linear thermal expansion near copper substrates, a high glass transition temperature, a very high Young's modulus, a relatively low dielectric constant, high thermal stability, and good film toughness.

(Example 8)

According to the method described in Example 4, polymerization was carried out using 4,4 ′ diaminobenzalide and the tetracarboxylic dianhydride described in Example 2 to obtain a transparent, uniform and viscous polyester imid. A precursor solution was obtained.

[0102] The polyesterimide precursor solution did not precipitate or gel at all even when left at room temperature and 20 ° C for one month, and showed extremely high solution storage stability. The intrinsic viscosity of the polyesterimide precursor measured with an Ostwald viscometer at 30 ° C. and 0.5% by weight in N, N-dimethylacetamide was 2.37 dLZg, which was an extremely high molecular weight substance.

[0103] This polyesterimide precursor solution was applied to a glass substrate and dried at 60 ° C for 2 hours. The obtained polyesterimide precursor film was placed on the substrate at 250 ° C under reduced pressure for 1 hour and further at 300 ° C. After performing thermal imidation for 1 hour, the substrate was peeled off to remove residual stress, and heat treatment was further performed at 350 ° C. for 1 hour to obtain a transparent polyesterimide film having a thickness of 20 m.

[0104] The polyesterimide film did not break even in the 180 ° bending test, and showed toughness.

As a result of dynamic viscoelasticity measurement of this polyesterimide film, no clear glass transition point was observed, and the film showed no thermoplasticity at all. This indicates that the polyesterimide film has extremely high dimensional stability. The coefficient of linear thermal expansion was as low as 6. Oppm ZK. Judging from the large birefringence value (Δη = 0.196), this is considered to be due to the in-plane orientation of the polyesterimide chain. The dielectric constant estimated from the average refractive index was 3.26, and the water absorption was 2.06%. The 5% weight loss temperature was 480 ° C in nitrogen and 470 ° C in air. Like this polyester immi The metal exhibited a very low coefficient of linear thermal expansion, high glass transition temperature, relatively low dielectric constant, high thermal stability, and good film toughness.

(Example 9)

4-Aminobenzoic acid 4'-aminofurol (APAB) lOmmol is placed in a well-dried closed reaction vessel with a stirrer, dissolved in N, N-dimethylacetamide sufficiently dehydrated with molecular sieves 4A, and then dissolved in this solution. Then, 10 mmol of the tetracarboxylic dianhydride powder described in Example 2 was gradually dried. The mixture was stirred at room temperature for 48 hours while appropriately diluting with the same solvent to obtain a transparent, uniform and viscous polyesterimide precursor solution.

This polyesterimide precursor solution did not precipitate or gel at all even when left at room temperature and 20 ° C. for one month, and showed extremely high solution storage stability. The intrinsic viscosity of the polyesterimide precursor measured in an N, N-dimethylacetamide at 30 ° C. and a concentration of 0.5% by weight with an Ostwald viscometer was 2.81 dLZg, which was an extremely high polymer.

The polyesterimide precursor solution was applied to a glass substrate and dried at 60 ° C. for 1 hour. The polyesterimide precursor film obtained was dried on the substrate at 250 ° C. under reduced pressure for 1 hour and further at 300 ° C. After performing thermal imidization at C for 1 hour and removing the substrate force, a final heat treatment was performed at 350 ° C for 1 hour to obtain a transparent polyesterimide film having a film thickness of 20 μm.

[0108] The polyesterimide film did not break even in the 180 ° bending test, and showed toughness.

As a result of dynamic viscoelasticity measurement (at room temperature up to 500 ° C) of the polyesterimide film, no clear glass transition point was observed. It was clear from the results that the dimensional stability was extremely high. The coefficient of linear thermal expansion was 3.3 ppmZK, an extremely low value equivalent to that of a silicon substrate. The extremely high birefringence value (Δη = 0.1990) suggests that this result is due to the high degree of in-plane orientation of the polyester imide chains. The water absorption was 0.75%, which was much lower than that of ordinary polyimide commercial products (water absorption 2.9%). The dielectric constant measured at a frequency of 1 MHz with a high-precision LCR meter was 3.22, which was close to the dielectric constant 3.26 estimated from the average refractive index. The dielectric loss tangent was 0.025, which was a relatively low value. As for the tensile properties, the Young's modulus was 7.1 lGPa and the breaking strength was 0.22 GPa, which was extremely high elasticity and high strength, and the breaking elongation was 11%. The 5% weight loss temperature was 471 ° C in nitrogen and 452 ° C in air. Thus, the polyesterimide has a relatively low dielectric constant and And a very low coefficient of linear thermal expansion comparable to that of a silicon substrate, a very high Young's modulus, and a very low water absorption, and had sufficient film toughness.

(Example 10)

In a well-dried closed reaction vessel with a stirrer, 7 mmol of APAB and 3 mmol of 4,4'-oxydiamine were dissolved and dissolved in N, N-dimethylacetamide sufficiently dehydrated with molecular sieves 4A. 10 mmol of the tetracarboxylic dianhydride powder described in 2 was gradually added. The mixture was stirred at room temperature for 28 hours while appropriately diluting with the same solvent to obtain a transparent, uniform and viscous polyesterimide precursor solution.

This polyesterimide precursor solution did not precipitate or gel at all even when left at room temperature and 20 ° C. for one month, and showed extremely high solution storage stability. The intrinsic viscosity of the polyesterimide precursor measured with an Ostwald viscometer at 30 ° C. and 0.5% by weight in N, N-dimethylacetamide was 1.08 dLZg, which was a high polymer.

[0111] The polyesterimide precursor solution was applied to a glass substrate, and dried at 60 ° C for 1 hour. The resulting polyesterimide precursor film was placed on the substrate at 250 ° C under reduced pressure for 1 hour and further at 300 ° C. After performing thermal imidization at C for 1 hour and removing the substrate force, a final heat treatment was performed at 350 ° C for 1 hour to obtain a transparent polyesterimide film having a film thickness of 20 μm.

[0112] The polyesterimide film did not break even in the 180 ° bending test, and showed toughness.

As a result of dynamic viscoelasticity measurement (at room temperature to 500 ° C) of the polyesterimide film, the glass transition point was 395 ° C. In addition, even at a temperature equal to or higher than the glass transition temperature, the storage elastic modulus of the polyesterimide film was hardly reduced, indicating that the dimensional stability was high! The linear thermal expansion coefficient was 14.8 ppm ZK, almost the same value as that of a copper substrate. From the extremely high birefringence value (Δη = 0.1699), this result is considered to be due to the high degree of in-plane orientation of the polyesterimide chains. The water absorption was 0.66%, an extremely low value. The dielectric constant estimated from the average refractive index was 3.20. As for the tensile properties, the Young's modulus was 6.28 GPa and the breaking strength was 0.295 GPa, which was extremely high elasticity and strength, and the breaking elongation was 36%. The 5% weight loss temperature was 487 ° C in nitrogen and 485 ° C in air. Thus, the present polyesterimide has a relatively low dielectric constant, a low linear thermal expansion coefficient almost equal to that of a copper substrate, and an extremely high dielectric constant. It exhibited a high glass transition temperature, a very high Young's modulus and a very low water absorption, and had sufficient film toughness.

[0113] (Comparative Example 1)

An ester group-containing tetracarboxylic dianhydride was synthesized from 2,2′-biphenol and twice the molar amount of trimellitic anhydride chloride. This is the isomer of the tetracarboxylic dianhydride described in Example 1. From this acid dianhydride and p-phenylenediamine, a polyesterimide precursor was polymerized according to the methods shown in Examples 3 and 4. The intrinsic viscosity of the polyesterimide precursor measured in an N, N-dimethylacetamide at 30 ° C. and a concentration of 0.5% by weight with a Ostwald viscometer was 0.53 dLZg. This polyesterimide precursor solution was applied to a glass substrate, and dried at 60 ° C for 2 hours.The obtained polyesterimide precursor film was thermally imidized at 300 ° C for 1 hour under reduced pressure on the substrate. A transparent and tough polyesterimide film with a thickness of 20 m was obtained.

The linear thermal expansion coefficient of this polyesterimide film was as high as 66 ppmZK, and the required characteristics according to the present invention were satisfied. This is because the benzene rings are greatly twisted due to steric hindrance that cannot be caused by the 2,2'-biphenyl bond force in the acid dianhydride and the S-para bond. This is because spontaneous in-plane orientation was hardly induced.

Industrial applicability

[0115] The polyesterimide of the present invention has a low dielectric constant, a low coefficient of linear thermal expansion, a high glass transition temperature, and a sufficient film toughness. In addition to these, it preferably has a low water absorption. Since they can be held together, as precision electronic materials, for example, electronic devices such as flexible printed wiring boards, cover materials (protective films) for electronic circuits on flexible printed wiring boards, protective films for semiconductor devices, or interlayer insulating films for integrated circuits, In particular, it is suitable for use on flexible printed wiring boards. Particularly, the polyesterimide film of the present invention is laminated with a laminate, for example, amorphous silicon, by utilizing an extremely low linear thermal expansion coefficient comparable to that of a copper substrate or a silicon substrate as described in Example 410. It is also useful to use it as a base film for solar cells.

Claims

The scope of the claims

[1] Expression (1)

Where

A is

Is selected from divalent aromatic groups or alicyclic groups represented by

The force selected from a divalent aromatic group or an alicyclic group represented by the formula: wherein the steric structure of the cyclohexane ring in A and B is a chair-type trans configuration. Imide precursor.

[3] In N, N-dimethylacetamide, the intrinsic viscosity at 30 ° C. and a concentration of 0.5% by weight is 0.5%. 3. The polyesterimide precursor according to claim 1, which is 3 dLZg or more.

An organic solvent solution containing the polyesterimide precursor according to claim 13. Equation (2):

Where

Α and Β are each independently a divalent aromatic group, an alicyclic group or a combination thereof. However, the bonding positions of the divalent groups are all in the para-position or a relation equivalent thereto. Polyester imide characterized by containing a repeating unit

A is

Is selected from divalent aromatic groups or alicyclic groups represented by

The force selected from a divalent aromatic group or an alicyclic group represented by <H.However, the steric structure of the cyclohexane ring in A and B is in a chair-type trans configuration. Polyester imide. [7] A method for producing a polyesterimide film,

(i) preparing a solution of the polyesterimide precursor according to claim 13 in an organic solvent;

And producing a polyesterimide film.

[8] A polyesterimide film obtained by the method according to claim 7.

[9] The polyesterimide film according to claim 8, having a dielectric constant lower than 3.3, a linear thermal expansion coefficient lower than 30 ppmZK, a glass transition temperature of 300 ° C or higher, and sufficient film toughness.

[10] An electronic device comprising the polyesterimide film according to claim 8 or 9.