KR20240026123A - Polyamic acid, polyimide and their uses - Google Patents

Abstract

It is a polyamic acid that is a copolymerization product of at least carboxylic acids, diamines, and silsesquioxane derivatives, and the silsesquioxane derivative has two or more dicarboxylic anhydride groups or two or more amino groups, and the silsesquioxane derivative The number of moles of structural units derived from the oxane derivative is within a certain range (for example, when the silsesquioxane derivative has the two or more dicarboxylic acid anhydride groups, the number of moles of structural units derived from the silsesquioxane derivative is set to A polyamic acid that is at least 0.0001 times and not more than 0.09 times the total number of moles of structural units derived from the sesquioxane derivative and the number of moles of structural units derived from the above-mentioned carboxylic acids.

Description

Polyamic acid, polyimide and their uses

The present invention relates to a polyamic acid containing a silsesquioxane compound as a copolymerization component, a polyimide obtained by imidating the same, and uses thereof, such as polyimide films, laminates thereof, flexible electronic devices, etc. I can hear it.

Polyimide film has excellent heat resistance and good mechanical properties, and is widely used in the electrical and electronic fields as a flexible material. However, since general polyimide films are colored yellow-brown, they cannot be applied to areas that require light transmission, such as display devices.

Meanwhile, display devices are becoming thinner and lighter, and more flexible devices are being required. Therefore, attempts are being made to change the substrate material from a glass substrate to a flexible polymer film substrate. However, colored polyimide films cannot be used as a substrate material for liquid crystal displays that display by turning on/off light transmission, and cannot be used in peripheral circuits such as TAB or COF on which the drive circuit of the display device is mounted, or in reflective displays. It could only be applied to a very small number of areas, such as the back side of anti-corrosion or self-luminous display devices.

Against this background, development of colorless and transparent polyimide films is in progress. When using a polyimide film as a flexible electronic circuit board, in addition to colorless transparency, low coefficient of linear expansion (CTE), and low retardation (Rth), it is necessary to maintain resistance to bending and mechanical strength under high temperature conditions during circuit formation. Therefore, high elastic modulus, mechanical strength, and high glass transition temperature (Tg) are required.

As a representative example, there has been an attempt to develop a colorless and transparent polyimide film using fluorinated polyimide resin, semi-cyclic or polycyclic polyimide resin, etc. (Patent Documents 1 to 3). These films have little coloring and are transparent, but the mechanical strength does not increase with colored polyimide films, and in cases where industrial production and applications exposed to high temperatures are assumed, thermal decomposition or oxidation reactions occur. It is not necessarily possible to maintain colorlessness and transparency.

From this point of view, a method of heat treatment while blowing out a gas with a specified oxygen content has been proposed (Patent Document 4), but the manufacturing cost is high in an environment where the oxygen concentration is less than 18%, and industrial production is very difficult. .

In addition, as a means of further improving the properties of organic materials, the so-called organic-inorganic hybridization technology is used to impart the characteristics of inorganic materials, such as high heat resistance, chemical resistance, and high surface hardness, by combining organic and inorganic materials. There is. For example, it is known that CTE, Rth, and Tg can be improved while maintaining transparency by combining transparent polyimide and silica nanoparticles. However, as the mixing amount of silica nanoparticles increases, the film becomes hard and brittle, and the mechanical strength decreases.

On the other hand, silsesquioxane with RSiO _3/21.5 as the basic unit can easily provide an organic-inorganic hybrid cured product by having a substituent in R that can react with organic materials, so studies for practical use are underway. There is (for example, patent document 5). Attempts are being made to improve heat resistance and processability by complexing silsesquioxane, which has high heat resistance and flexibility, with polyimide. It is known that the thermal decomposition temperature is improved by charge transfer interaction between the imide portion of polyimide and silsesquioxane (Non-patent Document 1).

[Patent Document 1] Japanese Patent Publication No. 11-106508 [Patent Document 2] Japanese Patent Publication No. 2002-146021 [Patent Document 3] Japanese Patent Publication No. 2002-348374 [Patent Document 4] Publication No. WO2008/146637 [Patent Document 5] Japanese Patent No. 3653976 [Patent Document 6] Japanese Patent Publication No. 2004-331647 [Patent Document 7] Japanese Patent Publication No. 2006-265243 [Patent Document 8] Japanese Patent Publication No. 2007-302635 [Patent Document 9] WO2003/024870

[Non-patent Document 1] Thermochimica Acta 2004, 417, pp. 133-142 [Non-patent Document 2] European Polymer Journal 2011, 47 (6), pp. 1328-1337 [Non-patent Document 3] Chemistry Letters, 2014, Vol.43, No. 10, pp.1532-1534 [Non-patent Document 4] Chemistry Letters, 2018, Vol.47, No. 12, pp.1530-1533

However, since the flexible silsesquioxane structure reduces the rigidity of the polyimide, silsesquioxane composite polyimide usually has a problem of showing a relatively low elastic modulus and low Tg (Non-patent Document 2).

As described above, it is very difficult to manufacture a colorless and transparent polyimide film that has a low coefficient of linear expansion and high heat resistance while also having high mechanical strength. For semi-cyclic or polyalicyclic polyimides, colorless transparency improves when the monomer component having an alicyclic structure is increased, but mechanical strength decreases due to a decrease in intermolecular interactions, making it difficult to produce it as a film. On the other hand, when an aromatic monomer is introduced, the toughness increases and the mechanical properties of the film improve due to increased intermolecular interactions, but it becomes prone to coloring and the colorless transparency decreases. By introducing a filler (inorganic component) with a close refractive index to the resin component, heat resistance and colorless transparency are improved, the coefficient of linear expansion is lowered, and processing suitability is improved. However, looking at the physical properties of the resin, it becomes hard and brittle, and the mechanical properties deteriorate. .

Therefore, there is a trade-off relationship between practical properties such as heat resistance and mechanical properties and colorlessness (transparency to whiteness), and there has been a demand for a method of producing polyimide films with improved toughness while maintaining other main properties. .

Therefore, the purpose of the present invention is to provide a polyamic acid useful as a raw material for producing a polyimide film with improved toughness while maintaining other main properties. Another object of the present invention is to provide a polyamic acid composition containing this polyamic acid and a polyimide obtained by imidating this polyamic acid. Here, “maintaining other main characteristics” means maintaining “other main characteristics” under three types of firing conditions in the Examples described later, specifically, at least B1 among B1, B2, and B3.

Furthermore, another object of the present invention is to provide a polyimide film with improved toughness while maintaining other main characteristics, a laminate thereof, a flexible electronic device using the polyimide film, and a method for manufacturing the same.

As a result of intensive research to solve the above problem, the present inventors have found that the above object can be achieved by a polyamic acid containing a specific amount of a silsesquioxane compound as a copolymerization component, and have completed the present invention. .

That is, the present invention includes the following contents.

[1] Polyamic acid, which is a copolymerization product of at least carboxylic acids, diamines, and silsesquioxane derivatives,

The silsesquioxane derivative has two or more dicarboxylic anhydride groups or two or more amino groups,

When the silsesquioxane derivative has two or more dicarboxylic acid anhydride groups, the number of moles of structural units derived from the silsesquioxane derivative (provided that the silsesquioxane derivative has more than two dicarboxylic acid anhydride groups) When having an acid anhydride group, this number of moles is the total number of moles of the silsesquioxane derivative divided by the total number of dicarboxylic acid anhydride groups of the silsesquioxane derivative divided by 2) is the number of moles of the silsesquioxane derivative is 0.0001 times or more and 0.09 times or less relative to the sum of the number of moles of structural units derived from and the number of moles of structural units derived from the above carboxylic acids,

When the silsesquioxane derivative has more than two amino groups, the number of moles of structural units derived from the silsesquioxane derivative (however, when the silsesquioxane derivative has more than two amino groups, this number of moles is is the total number of moles of the silsesquioxane derivative divided by the total number of amino groups of the silsesquioxane derivative and doubled) is the number of moles of structural units derived from the silsesquioxane derivative and the number of moles of structural units derived from the diamines A polyamic acid that is 0.0001 times to 0.09 times the total number of moles of structural units.

[2] The polyamic acid according to [1], wherein the silsesquioxane derivative has the two or more dicarboxylic anhydride groups.

[3] The polyamic acid according to [1], wherein the silsesquioxane derivative has the two or more amino groups.

[4] Each of the amino groups has a linking group that connects the amino group to Si that is closest in bond to the amino group among the Si constituting the silsesquioxane derivative,

The polyamic acid according to [3], wherein the linking group each independently has a substituted or unsubstituted aromatic ring bonded to the amino group.

[5] The polyamic acid according to any one of [1] to [4], wherein the polyamic acid does not have a structural unit derived from 3,3',4,4'-biphenyltetracarboxylic dianhydride.

[6] The polyamic acid according to any one of [1] to [5], wherein the silsesquioxane derivative has a double decker structure, a basket structure, a random structure, a ladder structure, or a chair structure.

[7] The polysaccharide according to any one of [1] to [6], wherein the silsesquioxane derivative has a structure represented by the following general formula (hereinafter sometimes referred to as “general formula AA-D1”) Amic acid.

(In the formula, R ¹ is each independently a substituted or unsubstituted, straight-chain or branched alkyl group having 1 to 9 carbon atoms,

A substituted or unsubstituted aryl group with 15 carbon atoms or less, or

Represents a substituted or unsubstituted arylalkyl group having 15 carbon atoms or less,

Q ¹ is each independently a substituted or unsubstituted, straight-chain or branched alkyl group having 1 to 9 carbon atoms,

A substituted or unsubstituted aryl group with 15 carbon atoms or less, or

Represents a substituted or unsubstituted arylalkyl group having 15 carbon atoms or less,

Z ¹ is each independently a structure represented by the general formula (Z1-1),

In the general formula (Z1-1), Or it is a ring made by condensing at least two of these,

X belonging to Z ¹ and Si adjacent to Z ¹ may be connected by a single bond or may be connected by a linking group.)

[8] The polyamic acid according to [7], wherein R ¹ each independently represents a methyl group, an ethyl group, an isobutyl group, an isooctyl group, a trifluoropropyl group, or a phenyl group.

[9] The polyamic acid according to [7] or [8], wherein R ¹ represents a phenyl group.

[10] The polyamic acid according to any one of [7] to [9], wherein Q ¹ each independently represents a methyl group, an ethyl group, or a phenyl group.

[11] The polyamic acid according to any one of [7] to [10], wherein Q ¹ represents a methyl group.

[12] In the general formula (Z1-1), mountain.

[13] The polyamic acid according to any one of [7] to [12], in which X belonging to Z ¹ and Si adjacent to Z ¹ are connected by a single bond.

[14] The polyamic acid according to any one of [7] to [12], in which X belonging to Z ¹ and Si adjacent to Z ¹ are connected by a linking group.

[15] The polyamic acid according to any one of [7] to [14], wherein Z ¹ is one of the three structures shown below.

[16] The polysaccharide according to any one of [1] to [6], wherein the silsesquioxane derivative has a structure represented by the following general formula (hereinafter sometimes referred to as “general formula AA-D2”) Amic acid.

(In the formula, R ¹ is each independently a substituted or unsubstituted, straight-chain or branched alkyl group having 1 to 9 carbon atoms,

A substituted or unsubstituted aryl group with 15 carbon atoms or less, or

Represents a substituted or unsubstituted arylalkyl group having 15 carbon atoms or less,

Z ¹ is each independent,

At least two of Z ¹ are structures represented by the general formula (Z1-1),

In the general formula (Z1-1), Or it is a ring made by condensing at least two of these,

X belonging to Z ¹ and O adjacent to Z ¹ are connected by a linker,

If Z ¹ that is not a structure represented by the general formula (Z1-1) exists, Z ¹ that is not the structure is H or a structure represented by the general formula (Z1-S),

Q ^S1 in the general formula (Z1-S) is each independently a substituted or unsubstituted, straight-chain or branched alkyl group having 1 to 9 carbon atoms,

A substituted or unsubstituted aryl group with 15 carbon atoms or less, or

Represents a substituted or unsubstituted arylalkyl group having 15 carbon atoms or less.)

[17] The polyamic acid according to [16], wherein R ¹ each independently represents a methyl group, an ethyl group, an isobutyl group, an isooctyl group, a trifluoropropyl group, or a phenyl group.

[18] The polyamic acid according to [16] or [17], wherein R ¹ represents a phenyl group.

[19] The polyamic acid according to any one of [16] to [18], wherein X in the general formula (Z1-1) is each independently a substituted or unsubstituted aromatic ring.

[20] The polyamic acid according to any one of [16] to [19], wherein the linking group is a carbonyl group.

[21] The polyamic acid according to any one of [16] to [20], wherein Z ¹ has the structure shown below.

[22] The polyamic acid according to any one of [16] to [21], wherein Q ^S1 in the general formula (Z1-S) each independently represents a methyl group, an ethyl group, or a phenyl group.

[23] The polysaccharide according to any one of [1] to [6], wherein the silsesquioxane derivative has a structure represented by the following general formula (hereinafter sometimes referred to as “general formula AA-C1”) Amic acid.

(In the formula, R ¹ is each independently a substituted or unsubstituted, straight-chain or branched alkyl group having 1 to 9 carbon atoms,

A substituted or unsubstituted aryl group with 15 carbon atoms or less, or

Represents a substituted or unsubstituted arylalkyl group having 15 carbon atoms or less,

Z ¹ is each independent,

At least two of Z ¹ are structures represented by the general formula (Z1-1),

In the general formula (Z1-1), Or it is a ring made by condensing at least two of these,

X belonging to Z ¹ and O adjacent to Z ¹ are connected by a linker,

If Z ¹ that is not a structure represented by the general formula (Z1-1) exists, Z ¹ that is not the structure is H or a structure represented by the general formula (Z1-S),

Q ^S1 in the general formula (Z1-S) is each independently a substituted or unsubstituted, straight-chain or branched alkyl group having 1 to 9 carbon atoms,

A substituted or unsubstituted aryl group with 15 carbon atoms or less, or

Represents a substituted or unsubstituted arylalkyl group having 15 carbon atoms or less.)

[24] The polyamic acid according to [23], wherein R ¹ each independently represents a methyl group, an ethyl group, an isobutyl group, an isooctyl group, a trifluoropropyl group, or a phenyl group.

[25] The polyamic acid according to [23] or [24], wherein R ¹ represents a phenyl group.

[26] The polyamic acid according to any one of [23] to [25], wherein X in the general formula (Z1-1) is each independently a substituted or unsubstituted aromatic ring.

[27] The polyamic acid according to any one of [23] to [26], wherein the linking group is a carbonyl group.

[28] The polyamic acid according to any one of [23] to [27], wherein Z ¹ has the structure shown below.

[29] The polyamic acid according to any one of [23] to [28], wherein Q ^S1 in the general formula (Z1-S) each independently represents a methyl group, an ethyl group, or a phenyl group.

[30] The polysaccharide according to any one of [1] to [6], wherein the silsesquioxane derivative has a structure represented by the following general formula (hereinafter sometimes referred to as “general formula AA-Q1”) Amic acid.

(In the formula, Z ¹ is each independent,

At least two of Z ¹ are structures represented by the general formula (Z1-1),

In the general formula (Z1-1), Or it is a ring made by condensing at least two of these,

X belonging to Z ¹ and O adjacent to Z ¹ are connected by a linker,

If Z ¹ that is not a structure represented by the general formula (Z1-1) exists, Z ¹ that is not the structure is H or a structure represented by the general formula (Z1-S),

Q ^S1 in the general formula (Z1-S) is each independently a substituted or unsubstituted, straight-chain or branched alkyl group having 1 to 9 carbon atoms,

A substituted or unsubstituted aryl group with 15 carbon atoms or less, or

Represents a substituted or unsubstituted arylalkyl group having 15 carbon atoms or less.)

[31] The polyamic acid according to [30], wherein X in the general formula (Z1-1) is each independently a substituted or unsubstituted aromatic ring.

[32] The polyamic acid according to [30] or [31], wherein Q ^S1 in the general formula (Z1-S) each independently represents a methyl group, an ethyl group, or a phenyl group.

[33] The polysaccharide according to any one of [1] to [6], wherein the silsesquioxane derivative has a structure represented by the following general formula (hereinafter sometimes referred to as “general formula AM-D1”) Amic acid.

(In the formula, R ¹ is each independently a substituted or unsubstituted, straight-chain or branched alkyl group having 1 to 9 carbon atoms,

A substituted or unsubstituted aryl group with 15 carbon atoms or less, or

Represents a substituted or unsubstituted arylalkyl group having 15 carbon atoms or less,

Q ¹ is each independently a substituted or unsubstituted, straight-chain or branched alkyl group having 1 to 9 carbon atoms,

A substituted or unsubstituted aryl group with 15 carbon atoms or less, or

Represents a substituted or unsubstituted arylalkyl group having 15 carbon atoms or less,

Z ² is each independently a structure represented by the general formula (Z2-1) or a structure represented by the general formula (Z2-2),

Y in general formula (Z2-1) is a substituted or unsubstituted aromatic ring, a substituted or unsubstituted aliphatic ring with 4 to 10 carbon atoms, or a heterocycle in which at least one carbon constituting these rings is substituted with a hetero atom, Or it is a ring made by condensing at least two of these,

Y belonging to Z ² and Si adjacent to Z ² may be connected by a single bond or may be connected by a linking group,

The amino group belonging to general formula (Z2-2) and Si adjacent to Z ² are connected by a linking group.)

[34] The polyamic acid according to [33], wherein R ¹ each independently represents a methyl group, an ethyl group, an isobutyl group, an isooctyl group, a trifluoropropyl group, or a phenyl group.

[35] The polyamic acid according to [33] or [34], wherein R ¹ represents a phenyl group.

[36] The polyamic acid according to any one of [33] to [35], wherein Q ¹ each independently represents a methyl group, an ethyl group, or a phenyl group.

[37] The polyamic acid according to any one of [33] to [36], wherein Q ¹ represents a methyl group.

[38] The polyamic acid according to any one of [33] to [37], wherein Y in the general formula (Z2-1) is each independently a substituted or unsubstituted aromatic ring.

[39] The polyamic acid according to any one of [33] to [38], in which Y belonging to Z ² and Si adjacent to Z ² are connected by a single bond.

[40] The polyamic acid according to any one of [33] to [39], in which Y belonging to Z ² and Si adjacent to Z ² are connected by a linking group.

[41] The polyamic acid according to any one of [33] to [40], wherein Z ² is one of the two structures shown below.

[42] The polyamic acid according to any one of [33] to [41], wherein Z ² has the structure shown below.

[43] The polysaccharide according to any one of [1] to [6], wherein the silsesquioxane derivative has a structure represented by the following general formula (hereinafter sometimes referred to as “general formula AM-D2”) Amic acid.

(In the formula, R ¹ is each independently a substituted or unsubstituted, straight-chain or branched alkyl group having 1 to 9 carbon atoms,

A substituted or unsubstituted aryl group with 15 carbon atoms or less, or

Represents a substituted or unsubstituted arylalkyl group having 15 carbon atoms or less,

Z ² is each independent,

At least two of Z ² are structures represented by the general formula (Z2-1) or structures represented by the general formula (Z2-2),

Y in general formula (Z2-1) is a substituted or unsubstituted aromatic ring, a substituted or unsubstituted aliphatic ring with 4 to 10 carbon atoms, or a heterocycle in which at least one carbon constituting these rings is substituted with a hetero atom, Or it is a ring made by condensing at least two of these,

Y belonging to Z ² and O adjacent to Z ² are connected by a linker,

The amino group belonging to general formula (Z2-2) and O adjacent to Z ² are connected by a linking group,

If there is a Z 2 that is neither a structure represented by the general formula (Z2-1) nor a structure represented by the general formula (Z2-2), ^{Z 2 other} than these structures is expressed as H or general formula (Z2-S) It is a structure that

Q ^S1 in the general formula (Z2-S) is each independently a substituted or unsubstituted, straight-chain or branched alkyl group having 1 to 9 carbon atoms,

A substituted or unsubstituted aryl group with 15 carbon atoms or less, or

Represents a substituted or unsubstituted arylalkyl group having 15 carbon atoms or less.)

[44] The polyamic acid according to [43], wherein R ¹ each independently represents a methyl group, an ethyl group, an isobutyl group, an isooctyl group, a trifluoropropyl group, or a phenyl group.

[45] The polyamic acid according to [43] or [44], wherein R ¹ represents a phenyl group.

[46] The polyamic acid according to any one of [44] to [46], wherein Y in the general formula (Z2-1) is each independently a substituted or unsubstituted aromatic ring.

[47] The polyamic acid according to any one of [43] to [46], wherein Q ^S1 in the general formula (Z1-S) each independently represents a methyl group, an ethyl group, or a phenyl group.

[48] The polyamic acid according to any one of [43] to [47], wherein at least two of Z ² are any of the three structures shown below.

(In the formula, Q ¹ is each independently a substituted or unsubstituted, straight-chain or branched alkyl group having 1 to 9 carbon atoms,

A substituted or unsubstituted aryl group with 15 carbon atoms or less, or

Represents a substituted or unsubstituted arylalkyl group having 15 carbon atoms or less,

Q ² is Y constituting a single bond, a substituted or unsubstituted, straight-chain or branched alkylene group, a substituted or unsubstituted arylene group, or an alkylene group (specifically, a substituted or unsubstituted, straight-chain or branched alkylene group) It is a group in which the carbon adjacent to is substituted with a hetero atom.)

[49] The polysaccharide according to any one of [1] to [6], wherein the silsesquioxane derivative has a structure represented by the following general formula (hereinafter sometimes referred to as “general formula AM-C1”) Amic acid.

(In the formula, R ¹ is each independently a substituted or unsubstituted, straight-chain or branched alkyl group having 1 to 9 carbon atoms,

A substituted or unsubstituted aryl group with 15 carbon atoms or less, or

Represents a substituted or unsubstituted arylalkyl group having 15 carbon atoms or less,

Z ² is each independent,

At least two of Z ² are each independently a structure represented by the general formula (Z2-1) or a structure represented by the general formula (Z2-2),

Y in general formula (Z2-1) is a substituted or unsubstituted aromatic ring, a substituted or unsubstituted aliphatic ring with 4 to 10 carbon atoms, or a heterocycle in which at least one carbon constituting these rings is substituted with a hetero atom, Or it is a ring made by condensing at least two of these,

Y belonging to Z ² and O adjacent to Z ² are connected by a linker,

The amino group belonging to general formula (Z2-2) and O adjacent to Z ² are connected by a linking group,

If there is a Z ^{2 that is neither a structure represented by the general formula (Z2-1) nor a structure represented by the general formula (Z2-2), Z 2 that} is not one of these structures is expressed as H or the general formula (Z2-S) The structure is displayed,

Q ^S1 in the general formula (Z2-S) is each independently a substituted or unsubstituted, straight-chain or branched alkyl group having 1 to 9 carbon atoms,

A substituted or unsubstituted aryl group with 15 carbon atoms or less, or

Represents a substituted or unsubstituted arylalkyl group having 15 carbon atoms or less.)

[50] The polyamic acid according to [49], wherein R ¹ each independently represents a methyl group, an ethyl group, an isobutyl group, an isooctyl group, a trifluoropropyl group, or a phenyl group.

[51] The polyamic acid according to [49] or [50], wherein R ¹ represents a phenyl group.

[52] The polyamic acid according to any one of [49] to [51], wherein Y in the general formula (Z2-1) is each independently a substituted or unsubstituted aromatic ring.

[53] The polyamic acid according to any one of [49] to [52], wherein Q ^S1 in the general formula (Z1-S) each independently represents a methyl group, an ethyl group, or a phenyl group.

[54] The polyamic acid according to any one of [49] to [53], wherein at least two of Z ² are any of the three structures shown below.

(In the formula, Q ¹ is each independently a substituted or unsubstituted, straight-chain or branched alkyl group having 1 to 9 carbon atoms,

A substituted or unsubstituted aryl group with 15 carbon atoms or less, or

Represents a substituted or unsubstituted arylalkyl group having 15 carbon atoms or less,

Q ² is Y constituting a single bond, a substituted or unsubstituted, straight-chain or branched alkylene group, a substituted or unsubstituted arylene group, or an alkylene group (specifically, a substituted or unsubstituted, straight-chain or branched alkylene group) It is a group in which the carbon adjacent to is substituted with a hetero atom.)

[55] The polysaccharide according to any one of [1] to [6], wherein the silsesquioxane derivative has a structure represented by the following general formula (hereinafter sometimes referred to as “general formula AM-Q1”) Amic acid.

(In the formula, Z ² is each independent,

At least two of Z ² are each independently a structure represented by the general formula (Z2-1) or a structure represented by the general formula (Z2-2),

Y in general formula (Z2-1) is a substituted or unsubstituted aromatic ring, a substituted or unsubstituted aliphatic ring with 4 to 10 carbon atoms, or a heterocycle in which at least one carbon constituting these rings is substituted with a hetero atom, Or it is a ring made by condensing at least two of these,

Y belonging to Z ² and O adjacent to Z ² are connected by a linker,

The amino group belonging to general formula (Z2-2) and O adjacent to Z ² are connected by a linking group,

If there is a Z ^{2 that is neither a structure represented by the general formula (Z2-1) nor a structure represented by the general formula (Z2-2), Z 2 that} is not one of these structures is expressed as H or the general formula (Z2-S) The structure is displayed,

Q ^S1 in the general formula (Z2-S) is each independently a substituted or unsubstituted, straight-chain or branched alkyl group having 1 to 9 carbon atoms,

A substituted or unsubstituted aryl group with 15 carbon atoms or less, or

Represents a substituted or unsubstituted arylalkyl group having 15 carbon atoms or less.)

[56] The polyamic acid according to any one of [55], wherein Y in the general formula (Z2-1) is each independently a substituted or unsubstituted aromatic ring.

[57] The polyamic acid according to [55] or [56], wherein Q ^S1 in the general formula (Z1-S) each independently represents a methyl group, an ethyl group, or a phenyl group.

[58] The silsesquioxane derivative is,

General formula: thiol group-containing trialkoxysilanes a1 represented by R ¹ Si(OR ² ) ₃ ,

(Wherein, R ¹ represents an organic group in which at least one hydrogen of an aliphatic hydrocarbon group with 1 to 8 carbon atoms, an alicyclic hydrocarbon group with 4 to 8 carbon atoms, or an aromatic hydrocarbon group with 6 to 8 carbon atoms is substituted with a thiol group, R ² independently represents a hydrogen atom, an aliphatic hydrocarbon group with 1 to 8 carbon atoms, an alicyclic hydrocarbon group with 4 to 8 carbon atoms, or an aromatic hydrocarbon group with 6 to 8 carbon atoms.)

The thiol group of the condensate B of trialkoxysilanes a2 without a thiol group,

The above reactive group of dicarboxylic acid anhydride C having at least one reactive group selected from vinyl group, alkenyl group, cycloalkenyl group, alkynyl group and acid chloride group

The polyamic acid according to any one of [1] to [6], which is a silsesquioxane derivative formed by reacting with .

[59] The polyamic acid according to any one of [1] to [6] and [58], wherein the silsesquioxane derivative has structural units represented by the following general formulas (1) and (2).

(Wherein, Q ¹ represents an aliphatic hydrocarbon group, an alicyclic hydrocarbon group, or an aromatic hydrocarbon group having 1 to 8 carbon atoms, and Q ² represents a single bond, a hydrocarbon group having 1 to 8 carbon atoms, or a carbon atom of a hydrocarbon group having 1 to 8 carbon atoms. At least one of is an organic group or carbonyl group substituted with oxygen, and It is a small group, and one or more of the hydrogens bonded to them may be substituted with a hydrocarbon group, and 1.0 ≤ m ≤ 2.0, 1.4 ≤ n ≤ 1.6.)

(In the formula, Q ³ represents an aliphatic hydrocarbon group, an alicyclic hydrocarbon group, or an aromatic hydrocarbon group having 1 to 8 carbon atoms, and 1.4≤n≤1.6.)

[60] The molar ratio of the trialkoxysilanes a2 ([moles of a2]/[moles of a1+moles of a2]) or the molar ratio of the structural unit represented by general formula (2) ([structural unit (2)]/ The polyamic acid described in [59] wherein [structural unit (1) + structural unit (2)]) is 0.1 or more and 0.7 or less.

[61] Any one of [1] to [60], wherein the carboxylic acid is at least one selected from the group consisting of alicyclic tetracarboxylic acid anhydride, aromatic tetracarboxylic acid anhydride, tricarboxylic acid, and dicarboxylic acid. Polyamic acid described in .

[62] The poly according to any one of [1] to [61], wherein the carboxylic acids include at least one of pyromellitic dianhydride and 1,2,3,4-cyclobutanetetracarboxylic dianhydride. Amic acid.

[63] The polyamic acid according to any one of [1] to [62], wherein the carboxylic acids include pyromellitic dianhydride.

[64] The polyamic acid according to any one of [1] to [63], wherein the carboxylic acids include 1,2,3,4-cyclobutanetetracarboxylic dianhydride.

[65] The polyamic acid according to any one of [1] to [64], wherein the diamine is at least one selected from the group consisting of aromatic diamines, aliphatic diamines, and alicyclic diamines.

[66] [1] wherein the diamines include at least one of 2,2'-ditrifluoromethyl-4,4'-diaminobiphenyl and 4-amino-N-(4-aminophenyl)benzamide ] The polyamic acid according to any one of [65] to [65].

[67] The polyamic acid according to any one of [1] to [66], wherein the diamine includes 2,2'-ditrifluoromethyl-4,4'-diaminobiphenyl.

[68] The polyamic acid according to any one of [1] to [67], wherein the diamine includes 4-amino-N-(4-aminophenyl)benzamide.

[69] A polyamic acid composition containing the polyamic acid according to any one of [1] to [68] and a solvent.

[70] A polyimide obtained by imidizing the polyamic acid according to any one of [1] to [68].

[71] A polyimide film containing the polyimide described in [70].

[72] A laminate comprising the polyimide film described in [71] and an inorganic substrate.

[73] A process of forming an electronic device on the polyimide film surface of the laminate described in [72],

A method of manufacturing a flexible electronic device including a step of peeling off the inorganic substrate.

[74] A flexible electronic device comprising the polyimide film according to [71] and an electronic device formed on the polyimide film.

According to the present invention, it is possible to provide a polyamic acid useful as a raw material for producing a polyimide film with improved toughness while maintaining other main properties. Additionally, a polyamic acid composition containing this polyamic acid and a polyimide obtained by imidating this polyamic acid can be provided.

Furthermore, according to the present invention, it is possible to provide a polyimide film with improved toughness while maintaining other main characteristics, a laminate thereof, a flexible electronic device using the polyimide film, and a method for manufacturing the same.

Figure 1 is a diagram showing the ¹ H NMR (CDCl ₃ ) spectrum of SQ109 (PGMEA solution) used in Synthesis Example 2-1.
Figure 2 is a diagram showing the ¹ H NMR (CDCl ₃ ) spectrum of PGMEA. Here, δ=2.2 is a peak derived from acetone for instrument cleaning.
Figure 3 is a diagram showing the ¹ H NMR (CDCl ₃ ) spectrum of norbornene anhydride used in Synthesis Example 2-1. Here, δ=2.2 is a peak derived from acetone for instrument cleaning.
FIG. 4 is a diagram showing a ¹ H NMR (CDCl ₃ ) spectrum of the reaction mixture after the reaction in Synthesis Example 2-1.
Figure 5 is a diagram showing the ¹ H NMR (CDCl ₃ ) spectrum of silsesquioxane SQ2 having an acid anhydride group obtained in Synthesis Example 2-2.
Figure 6 is a diagram showing the ¹ H NMR (DMSO-d ₆ ) spectrum of silsesquioxane SQ3 having an acid anhydride group obtained in Synthesis Example 2-3.
Figure 7 is a diagram showing the ¹ H NMR (DMSO-d ₆ ) spectrum of silsesquioxane SQ4 having an acid anhydride group obtained in Synthesis Example 2-4.
Figure 8 is a diagram showing the ¹ H NMR (DMSO-d ₆ ) spectrum of silsesquioxane SQ5 having an acid anhydride group obtained in Synthesis Example 2-5.
Figure 9 is a diagram showing the ¹ H NMR (DMSO-d ₆ ) spectrum of silsesquioxane SQ6 having an acid anhydride group obtained in Synthesis Example 2-6.
Figure 10 is a diagram showing the ¹ H NMR (DMSO-d ₆ ) spectrum of silsesquioxane SQ7 having an acid anhydride group obtained in Synthesis Example 2-7.
Figure 11 is a diagram showing the ¹ H NMR (DMSO-d ₆ ) spectrum of silsesquioxane SQ8 having an acid anhydride group obtained in Synthesis Example 2-8.

The present invention will be described in detail below, but these are one aspect of the present invention, and the present invention is not limited to these contents.

In addition, hereinafter, silsesquioxane derivatives may be referred to as silsesquioxane compounds. That is, the terms silsesquioxane derivative and silsesquioxane compound are used as synonyms. Therefore, silsesquioxane derivatives can be referred to as silsesquioxane compounds.

The polyamic acid of the present invention is a copolymerization product of at least carboxylic acids, diamines, and silsesquioxane derivatives. As will be described later, silsesquioxane derivatives have two or more dicarboxylic acid anhydride groups (hereinafter sometimes simply referred to as “acid anhydride groups”) or two or more amino groups. Below, these will be explained.

<Silsesquioxane derivatives>

Silsesquioxane derivatives have two or more dicarboxylic acid anhydride groups (i.e., acid anhydride groups) or two or more amino groups. As a result, the silsesquioxane derivative can be copolymerized with carboxylic acids and diamines, and as a result, the toughness of the polyimide film can be improved. The detailed reason (i.e., the reason for improving the toughness of polyimide film by copolymerizing silsesquioxane derivatives with carboxylic acids and diamines) is not clear, but the relatively flexible silsesquioxane skeleton compared to inorganic fillers, etc. It is thought that this is because it becomes one domain, making it easier to allow deformation of the polyimide, which is the base material.

In addition, silsesquioxane is a term meaning a siloxane consisting mainly of T units (e.g., type T ₈ consisting of 8 T units, type T ₁₀ consisting of 10 T units, type T 12 consisting of ₁₂ T units). However, there are cases where it is used in a broader sense than this. Specifically, silsesquioxane includes not only siloxanes composed mainly of T units, but also siloxanes mainly composed of 12 or less Q units (e.g., type Q ₈ composed of 8 Q units or type Q 10 composed of ₁₀ Q units). There are cases where it is used as a term to mean something. Incidentally, the T unit is the unit expressed as RSiO _1.5 . The Q unit is a unit expressed as SiO ₂ . In these, R may represent an organic group.

In this specification, “silsesquioxane” of a silsesquioxane derivative is used in a broad sense. That is, “silsesquioxane” of the silsesquioxane derivative includes not only siloxane mainly composed of T units, but also siloxane mainly composed of 12 or less Q units. Accordingly, “silsesquioxane derivatives” also include not only siloxane derivatives mainly composed of T units, but also siloxane derivatives mainly composed of 12 or less Q units.

If the silsesquioxane derivative consists mainly of T units, units other than T units, such as M units (groups represented by R ₃ Si _O0.5 ), D units (units represented by R ₂ SiO), Q units It may be included. “The silsesquioxane derivative is mainly composed of T units” means that the number of T units is greater than the number of units other than T units (for example, the total number of M units, D units, and Q units). Therefore, for example, the silsesquioxane derivative may be composed of 8 T units and 2 D units. Even when the silsesquioxane derivative is mainly composed of Q units, it may also contain units other than Q units, such as M units, D units, and T units. “The silsesquioxane derivative is mainly composed of Q units” means that the number of Q units is greater than the number of units other than Q units (for example, the total number of M units, D units, and T units). Here, R may represent an organic group in the M unit and D unit as well.

The silsesquioxane derivative may have a double decker-type structure, a basket-type structure, a random-type structure, a ladder-type structure, or a chair-type structure. Among them, a double decker-type structure, a basket-type structure, and a random-type structure are preferable. A fully condensed structure (a structure that does not contain silanol groups) is preferable because it can suppress gelation of the polyamic acid solution. For example, a double decker type structure or a basket type structure are more preferable.

The double decker type structure may be ring-closed or ring-opened. Examples of the ring-closed double decker structure include a structure represented by the general formula AA-D1 described later, and a structure represented by the general formula AM-D1 described later. On the other hand, examples of the ring-opened double decker structure include a structure represented by the general formula AA-D2, which will be described later, and a structure represented by the general formula AM-D2, which will be described later.

The basket-type structure may be a complete basket-type structure or an incomplete basket-type structure (for example, an open corner structure, etc.). A complete basket-type structure is a structure in which a closed space is formed within the basket. For example, a complete basket-shaped structure is a structure in which a space is formed surrounded by six quadrilateral planes with four sides made of siloxane bonded Si-O-Si (hereinafter, this complete basket-shaped structure is referred to as a “hexahedral perfect basket-shaped structure”). There are cases where it happens.) It can be. On the other hand, the incomplete basket-type structure is a structure in which an open space is formed inside the basket and outside the basket.

An example of an incomplete basket-type structure is an open corner structure. Examples of the corner open structure include a structure represented by the general formula AA-C1, which will be described later, and a structure represented by the general formula AM-C1, which will be described later.

Silsesquioxane derivatives may have two or more acid anhydride groups. Silsesquioxane derivatives can react with diamines by having two or more acid anhydride groups. The number of acid anhydride groups per molecule of the silsesquioxane derivative may be, for example, 3 or more, 4 or more, 5 or more, or 6 or more. The number of acid anhydride groups per molecule may be, for example, 10 or less, or 8 or less. In particular, when the silsesquioxane derivative has a basket-like structure or a double decker-type structure, the number of acid anhydride groups per molecule is preferably, for example, 2 or more and 8 or less, and more preferably 2, 3, or 4. On the other hand, when the silsesquioxane derivative has a random structure, the number of acid anhydride groups per molecule is preferably 2 to 10, and more preferably 2.5 to 6. If the number of acid anhydride groups is within this range, the resulting polyimide chain is crosslinked appropriately, and the toughness of the polyimide film can be further improved.

In addition, when the silsesquioxane derivative has two or more acid anhydride groups, it does not have two or more amino groups described later.

Such silsesquioxane derivatives may, for example, have a structure represented by the following general formula (hereinafter sometimes referred to as “general formula AA-D1”).

(In the formula, R ¹ is each independently a substituted or unsubstituted, straight-chain or branched alkyl group having 1 to 9 carbon atoms,

A substituted or unsubstituted aryl group with 15 carbon atoms or less, or

Represents a substituted or unsubstituted arylalkyl group having 15 carbon atoms or less,

Q ¹ is each independently a substituted or unsubstituted, straight-chain or branched alkyl group having 1 to 9 carbon atoms,

A substituted or unsubstituted aryl group with 15 carbon atoms or less, or

Represents a substituted or unsubstituted arylalkyl group having 15 carbon atoms or less,

Z ¹ is each independently a structure represented by the general formula (Z1-1),

In the general formula (Z1-1), Or it is a ring made by condensing at least two of these,

X belonging to Z ¹ and Si adjacent to Z 1 may be connected by a single bond or may be connected by a linking group.)

Additionally, the silsesquioxane derivative represented by the general formula AA-D1 includes all geometric isomers within the scope of the general formula AA-D1. For example, as a geometric isomer represented by the general formula AA-D1, a pair of Q ¹ and Z ¹ bonded to Si exist in different directions of bonding to the ring plane, so the sil represented by the general formula AA-D1 Sesquioxane derivatives include these.

Regarding R ¹ , examples of the unsubstituted alkyl group include methyl group, ethyl group, propyl group, butyl group, pentyl group, hexyl group, heptyl group, octyl group, and nonyl group. These (strictly speaking, after the propyl group) may be linear or branched. For example, the propyl group may be an n-propyl group (i.e., 1-propyl group) or an isopropyl group (i.e., 1-methylethyl group). For example, the butyl group may be n-butyl, isobutyl, sec-butyl, or tert-butyl (i.e., 1,1-dimethylethyl). The hexyl group may be, for example, a 1,1,2-trimethylpropyl group. The octyl group may be, for example, a 2,2,4-trimethylpentyl group. Examples of the branched unsubstituted alkyl group include isopropyl group, isobutyl group, sec-butyl group, isooctyl group, 1,1,2-trimethylpropyl group, and 2,2,4-trimethylpentyl group.

Regarding R ¹ , the substituted alkyl group may be, for example, a group in which any number of hydrogen atoms constituting the unsubstituted alkyl group described above are substituted with halogen atoms. The halogen atom is preferably a fluorine atom, that is, F. As a substituted alkyl group, for example -CH ₂ CH ₂ CF ₃ , -CH ₂ CH ₂ CF ₂ CF ₃ , -CH ₂ CH 2 CF ₂ CF ₂ CF ₃ , -CH ₂ CH ₂ CF ₂ CF ₂ CF _{2 CF 3} , - CH ₂ CH ₂ CF ₂ CF ₂ CF ₂ CF ₂ CF ₃ , -CH ₂ CH ₂ CF ₂ CF 2 CF ₂ CF ₂ CF _{2 CF 3} , -CH ₂ CH ₂ CF(CF ₃ ) ₂ , -CH ₂ CH( CF ₃ )CF ₂ CF ₃ , -CH(CF ₃ )CH ₂ CF ₂ CF ₃ , -CH ₂ C(CF ₃ ) ₂ CF ₃ , -C(CF ₃ ) ₂ CH ₂ CF ₃ , -CH ₂ CH ₂ CF ₂ CF(CF ₃ ) ₂ , -CH ₂ CH ₂ CF (CF ₃ )CF ₂ CF ₃ , -CH ₂ CH ₂ C(CF ₃ ) ₂ CF ₃ . In addition to this, -CF ₃ , -CF ₂ CF ₃ , -CF ₂ CF ₂ CF ₃ , -CF(CF ₃ ) ₂ , -CF ₂ CF ₂ CF ₂ CF ₃ , -CF ₂ CF(CF ₃ ) ₂ , -C(CF ₃ ) ₃ , -(CF ₂ ) ₄ CF ₃ , -(CF ₂ ) ₂ CF(CF ₃ ) ₂ , -CF ₂ C(CF ₃ ) ₃ ,-CF(CF ₃ )CF ₂ CF ₂ CF ₃ , -(CF ₂ ) ₅ CF ₃ , -(CF ₂ ) ₃ CF(CF ₃ ) ₂ , -(CF ₂ ) ₄ CF(CF ₃ ) ₂ , -(CF ₂ ) ₇ CF ₃ , -(CF ₂ ) ₅ CF(CF ₃ ) ₂ , -(CF ₂ ) ₆ CF(CF ₃ ) ₂ . Among them, trifluoropropyl group, that is, -CH ₂ CH ₂ CF ₃ is preferable.

The alkyl group (specifically, a substituted or unsubstituted, straight-chain or branched alkyl group having 1 to 9 carbon atoms) for R ¹ may have an unsaturated bond. Examples include vinyl group, 2-propenyl group, 3-butenyl group, 5-hexenyl group, and 7-octenyl group.

The alkyl group (specifically, a substituted or unsubstituted, straight-chain or branched alkyl group with 1 to 9 carbon atoms) for R ¹ preferably has 1 to 8 carbon atoms, and preferably 1, 2, 3, 4 or 8. Here, this carbon number means the carbon number including the substituent.

Regarding R ¹ , examples of unsubstituted aryl groups include phenyl group, 1-naphthyl group, 2-naphthyl group, and fluorenyl group.

Regarding R ¹ , the substituted aryl group may be, for example, a group in which the hydrogen atoms constituting the above-mentioned unsubstituted aryl group are substituted with any number of other atoms and/or other atomic groups. For example, the unsubstituted aryl group described above may be a group in which any number of hydrogen atoms are substituted with an alkyl group (specifically, a substituted or unsubstituted, straight-chain or branched alkyl group having 1 to 9 carbon atoms). The unsubstituted aryl group described above may be a group in which any number of hydrogen atoms are substituted with halogen atoms. The halogen atom is preferably a fluorine atom, that is, F. As a substituted aryl group, for example, o-tolyl group, m-tolyl group, p-tolyl group, 4-ethylphenyl group, 4-propylphenyl group, 4-butylphenyl group, 4-pentylphenyl group, 4-heptylphenyl group, 4-octyl group. Phenyl group, 4-nonylphenyl group, 2,4-dimethylphenyl group, 2,4,6-trimethylphenyl group, 2,4,6-triethylphenyl group, 4-(1-methylethyl)phenyl group, 4-(1,1- Dimethylethyl)phenyl group, 4-(2-ethylhexyl)phenyl group, and 2,4,6-tris(1-methylethyl)phenyl group. In addition, pentafluorophenyl group, 4-fluorophenyl group, 4-chlorophenyl group, and 4-bromophenyl group may be mentioned. In addition, 4-methoxyphenyl group, 4-ethoxyphenyl group, 4-propoxyphenyl group, 4-butoxyphenyl group, 4-pentyloxyphenyl group, 4-heptyloxyphenyl group, 4-(1-methylethoxy)phenyl group, 4 -(2-methylpropoxy)phenyl group, 4-(1,1-dimethylethoxy)phenyl group, 4-ethenylphenyl group, 4-(1-methylethenyl)phenyl group, 4-(3-butenyl)phenyl group You may hear it.

The number of carbon atoms of the aryl group (specifically, a substituted or unsubstituted aryl group with 15 carbon atoms or less) of R ¹ is preferably 12 or less, more preferably 8 or less, and still more preferably 6 or less. This carbon number refers to the carbon number including the substituent.

Examples of the arylalkyl group for R ¹ , especially the unsubstituted arylalkyl group, include benzyl group and phenethyl group. Regarding R ¹ , the substituted arylalkyl group may be, for example, a group in which the hydrogen atoms constituting the above-mentioned unsubstituted arylalkyl group are substituted with any number of other atoms and/or different atomic groups. For example, the unsubstituted arylalkyl group described above may be a group in which any number of hydrogen atoms are substituted with an alkyl group (specifically, a substituted or unsubstituted, straight-chain or branched alkyl group having 1 to 9 carbon atoms). The unsubstituted arylalkyl group described above may be a group in which hydrogen atoms constituting an arbitrary number of halogen atoms are substituted. The halogen atom is preferably a fluorine atom, that is, F.

The number of carbon atoms of the arylalkyl group (specifically, a substituted or unsubstituted arylalkyl group with 15 carbon atoms or less) for R ¹ is preferably 12 or less, more preferably 10 or less, and still more preferably 8 or less. This carbon number refers to the carbon number including the substituent.

R ¹ is preferably a methyl group, ethyl group, isobutyl group, isooctyl group, trifluoropropyl group, or phenyl group. Among them, the phenyl group is more preferable because there is interaction between aromatic rings and it exhibits high heat resistance.

The description of Q ¹ is omitted because it overlaps with the description of R ¹ . In this way, the description of R ¹ can also be treated as the description of Q ¹ . Since there is a specific most suitable embodiment for Q ¹ , a description of the most suitable embodiment is added. Specifically, Q ¹ is preferably a methyl group, an ethyl group, or a phenyl group, and a methyl group is more preferable because the manufacturing difficulty is relatively low.

Regarding Z ¹ , It is a substituted heterocycle, or a ring made by condensing at least two of these rings.

Examples of unsubstituted aromatic rings include benzene rings and naphthalene rings. Among them, a benzene ring is preferable because the difficulty in manufacturing is relatively low. Meanwhile, the substituted aromatic ring may be, for example, a group in which any number of hydrogen atoms constituting the unsubstituted aromatic ring described above are substituted with a substituted or unsubstituted, straight-chain or branched alkyl group having 1 to 9 carbon atoms. The description of this alkyl group is omitted because it overlaps with the description of R ¹ . Accordingly, the description of R ¹ can also be treated as a description of this alkyl group.

Heterocycles in which at least one carbon constituting the unsubstituted aromatic ring is substituted with a hetero atom include, for example, a pyridine ring, a pyrrole ring, a furan ring, a thiophene ring, and a thiazole ring (for example, a 1,3-thiazole ring). Examples of heteroatoms include nitrogen atoms, oxygen atoms, and sulfur atoms. On the other hand, a heterocycle in which at least one carbon constituting the substituted aromatic ring is substituted with a hetero atom is, for example, a substituted or unsubstituted, straight chain ring having 1 to 9 carbon atoms in an arbitrary number of hydrogen atoms constituting the above-mentioned unsubstituted heterocycle. Alternatively, it may be a structure substituted with a branched alkyl group. The description of this alkyl group is omitted because it overlaps with the description of R ¹ . Accordingly, the description of R ¹ can also be treated as a description of this alkyl group.

Unsubstituted aliphatic rings having 4 to 10 carbon atoms, such as cyclobutane, cyclopentane, cyclohexane, cycloheptane, cyclooctane, cyclononane, cyclodecane, norbornane (i.e., bicyclo[2.2.1]heptane), Cyclo[2.2.2]octane can be mentioned. Among them, because of their relatively high thermal stability, cross-linked aliphatic rings such as norbornane and bicyclo[2.2.2]octane are preferable, and norbornane and bicyclo[2.2.2]octane are more preferable. Norbornane is more preferred. On the other hand, the substituted aliphatic ring may be, for example, a group in which any number of hydrogen atoms constituting the above-mentioned unsubstituted aliphatic ring are substituted with a substituted or unsubstituted, straight-chain or branched alkyl group having 1 to 6 carbon atoms. The description of this alkyl group is omitted because it overlaps with the description of R ¹ . Accordingly, the description of R ¹ can also be treated as a description of this alkyl group.

A heterocycle in which at least one carbon constituting an unsubstituted aliphatic ring having 4 to 10 carbon atoms is substituted with a hetero atom, for example, between the bridgehead atoms of norbornane, specifically the shortest bridge of norbornane. An example is a structure in which the C atom constituting the methylene group between the constituting bridge atoms is replaced with an oxygen atom. That is, a structure in which the methylene group between the bridge atoms of norbornane is substituted with an ether bond can be mentioned. In addition, for example, thiane and dithiane (for example, 1,4-dithiane) may be mentioned. Examples of heteroatoms include nitrogen atoms, oxygen atoms, and sulfur atoms. On the other hand, a heterocycle in which at least one carbon constituting a substituted aliphatic ring having 4 to 10 carbon atoms is substituted with a hetero atom is, for example, a substituted ring having an arbitrary number of hydrogen atoms constituting the above-mentioned unsubstituted heterocycle having 1 to 6 carbon atoms. Alternatively, it may be a group substituted with an unsubstituted, straight-chain or branched alkyl group. The description of this alkyl group is omitted because it overlaps with the description of R ¹ . Accordingly, the description of R ¹ can also be treated as a description of this alkyl group.

Additionally, the number of carbon atoms of the aliphatic ring (specifically, a substituted or unsubstituted aliphatic ring having 4 to 10 carbon atoms) may be, for example, 6 or more, 7 or more, or 8 or more. This carbon number may be 9 or less, and may be 8 or less. This carbon number refers to the carbon number including the substituent.

At least two of these rings (specifically, a substituted or unsubstituted aromatic ring, a substituted or unsubstituted aliphatic ring with 4 to 10 carbon atoms, or a heterocycle in which at least one carbon constituting these rings is substituted with a hetero atom) are condensed. Examples of one ring, that is, a condensed ring, include benzofuran (eg, 1-benzofuran), benzothiophene (eg, 1-benzothiophene), and benzothiazole.

For the reason that yellowing of polyimide (for example, polyimide film) can be further suppressed under high temperature conditions around 400°C, it is preferable that X is a substituted or unsubstituted aromatic ring. From the viewpoint of manufacturing difficulty, an unsubstituted aromatic ring is more preferable. From the viewpoint of being available as a commercial product (e.g. DDSQ manufactured by Nippon Zairyo Ken Co., Ltd.), a substituted or unsubstituted aliphatic ring having 4 to 10 carbon atoms is preferable, and an unsubstituted aliphatic ring having 4 to 10 carbon atoms is preferable. .

X belonging to Z ¹ and Si adjacent to Z ¹ may be connected by a single bond or may be connected by a linking group. As a linking group connecting the two, for example, a substituted or unsubstituted, straight-chain or branched alkylene group, a substituted or unsubstituted arylene group, a group represented by the following structural formula (CS), an ester group (i.e., an ester bond), an amide group ( That is, amide bond) and any combination of two or more thereof. Here, each connector may be independent. In other words, each connector may have a unique structure.

(In the formula, Q ¹ is each independently a substituted or unsubstituted, straight-chain or branched alkyl group having 1 to 9 carbon atoms,

A substituted or unsubstituted aryl group with 15 carbon atoms or less, or

Represents a substituted or unsubstituted arylalkyl group having 15 carbon atoms or less,

n is an integer from 0 to 8,

Q ² is a single bond, substituted or unsubstituted, straight-chain or branched alkylene group, substituted or unsubstituted arylene group, or It is a group in which the adjacent carbon is substituted with a hetero atom,

The O shown at the end is connected to Si adjacent to Z ¹ , and the Q ² shown at the end is connected to X.)

“Q ² shown at the end is connected to X” means that when Q ² shown at the end is a single bond, Si adjacent to ^{Q 2 shown} at the end is connected to In the case where the carbon adjacent to

Regarding linking groups, unsubstituted, straight-chain or branched alkylene groups, such as methylene group, ethylene group, n-propylene group, n-butylene group, tert-butylene group, n-pentylene group, n-hexylene group, n- Heptylene group and n-octylene group can be mentioned.

The substituted, straight-chain or branched alkylene group may be, for example, a group in which any number of hydrogen atoms constituting the unsubstituted alkylene group described above are substituted with halogen atoms. Examples of the halogen atom include a fluorine atom.

The number of carbon atoms of the alkylene group (specifically, substituted or unsubstituted, straight-chain or branched alkylene group) is preferably 10 or less, more preferably 6 or less, and still more preferably 3 or less. This carbon number refers to the carbon number including the substituent.

Regarding the linking group, examples of the unsubstituted arylene group include o-phenylene group, m-phenylene group, p-phenylene group, and naphthylene group (eg, 2,6-naphthylene group).

The substituted arylene group may be, for example, a group in which any number of hydrogen atoms constituting the unsubstituted arylene group described above are substituted with an alkyl group (for example, a methyl group).

The number of carbon atoms of the arylene group (specifically, the substituted or unsubstituted arylene group) is preferably 15 or less, more preferably 12 or less, and still more preferably 7 or less. This carbon number refers to the carbon number including the substituent.

Regarding the linking group represented by structural formula (CS), the description of Q ¹ is omitted because it overlaps with the description of R ¹ . In this way, the description of R ¹ can also be treated as the description of Q 1 . Since there is a specific most suitable embodiment for Q ¹ , a description of the most suitable embodiment is added. Specifically, Q ¹ is preferably a methyl group, ethyl group, isopropyl group, isobutyl group, sec-butyl group, tert-butyl group, or phenyl group.

n is an integer from 0 to 8. Since n can lower the coefficient of linear expansion (CTE) of polyimide (for example, polyimide film), n is preferably 5 or less, more preferably 3 or less, and even more preferably 1 or less, that is, 0 or 1.

Regarding the linking group represented by structural formula (CS), the description of the alkylene group (specifically, a substituted or unsubstituted, straight-chain or branched alkylene group) of Q ² refers to the alkylene group (specifically, a substituted or unsubstituted, straight-chain) described above. or branched alkylene group), so it is omitted because it overlaps with the description. Accordingly, the description of the alkylene group described above can also be treated as an explanation of the alkylene group of Q ² .

Regarding the linking group represented by structural formula (CS), the description of the arylene group (specifically, a substituted or unsubstituted arylene group) of Q ² overlaps with the description of the arylene group (specifically, a substituted or unsubstituted arylene group) described above. It is omitted because it is Accordingly, the description of the arylene group described above can also be treated as a description of the arylene group of Q ² .

Regarding the linking group represented by the structural formula (CS), Q ² is a group in which the carbon adjacent to (For example, methylene group, ethylene group, n-propylene group, n-butylene group, tert-butylene group, n-pentylene group, n-hexylene group, n-heptylene group, n-octylene group) Examples of this include groups in which the carbon adjacent to Among them, an n-butylene group, that is, a group in which the carbon adjacent to Also in this case, the carbon number of this group (i.e. Q2) is 3.

Regarding the linking group represented by structural formula (CS), Q ² is a hetero atom, for example, a nitrogen atom, an oxygen atom, or a sulfur atom. Among these, an oxygen atom and a sulfur atom are preferable, and an oxygen atom is more preferable.

As the linking group, a combination of a substituted or unsubstituted arylene group and an amide group is preferable, and a combination of a p-phenylene group and an amide group is more preferable. Specifically, the following structure is preferable. Additionally, the structural formula below shows that the p-phenylene group is bonded to Si. It indicates that the amide group is bonded to X. In other words, it indicates that the carbon constituting the amide group is bonded to X.

When both (that is, X belonging to Z ¹ and Si adjacent to Z ¹ ) are connected by this linking group, Z ¹ preferably has the following structure.

Both (i.e., X belonging to Z ¹ and Si adjacent to Z ¹ ) are preferably connected by a single bond. This is because the two are connected by a single bond, so that yellowing of polyimide (for example, polyimide film) under high temperature conditions can be further suppressed.

When both are connected by a single bond, the following structure is preferable as the structure represented by general formula (Z1-1). That is, when both are connected by a single bond, Z ¹ preferably has the following structure.

Silsesquioxane derivatives represented by the general formula AA-D1 are described, for example, in Japanese Patent Application Laid-Open No. 2004-331647 (the corresponding patent publication is Japanese Patent Application Publication No. 448334) and Japanese Patent Application Laid-Open No. 2006-265243 (this). The corresponding patent publication is Japanese Patent No. 5082258), Japanese Patent Laid-Open No. 2007-302635 (the corresponding patent publication is Japanese Patent No. 4946169), and WO2003/024870. You can.

For example, based on these documents, a compound in which all Z ¹ in the general formula AA-D1 is a hydrogen atom was prepared, and this compound (i.e., a compound having a SiH group containing H as Z ¹ and Si adjacent to Z ¹ ) was prepared. A silsesquioxane derivative represented by the general formula AA-D1 can be produced by reacting a compound having an acid anhydride group with a silsesquioxane derivative. In this reaction, for example, hydrosilylation can be used. That is, a reaction in which a compound having a SiH group is added to an unsaturated bond such as a carbon-carbon double bond along with cleavage of the Si-H bond can be used. When hydrosilylation is used, the compound having an acid anhydride group may have an unsaturated bond such as a carbon-carbon double bond (eg, a vinyl group). On the other hand, in the reaction between a compound having a SiH group and a compound having an acid anhydride group, a coupling reaction is performed, specifically, a coupling reaction between a compound having a SiH group and an aryl halide using a noble metal catalyst such as ruthenium, platinum, palladium, and rhodium. You can also use it. When using a coupling reaction, a compound having an acid anhydride group or a compound having a functional group that can be converted to an acid anhydride group may have an aryl halide structure. Examples of functional groups that can be converted to acid anhydride groups include diester groups.

In addition, among the silsesquioxane derivatives represented by the general formula AA-D1, for example, the following silsesquioxane derivatives can be obtained as commercial products (for example, DDSQ manufactured by Nippon Dairy Science Ken Co., Ltd.).

The silsesquioxane derivative may, for example, have a structure represented by the following general formula (hereinafter sometimes referred to as “general formula AA-D2”).

(In the formula, R ¹ is each independently a substituted or unsubstituted, straight-chain or branched alkyl group having 1 to 9 carbon atoms,

A substituted or unsubstituted aryl group with 15 carbon atoms or less, or

Represents a substituted or unsubstituted arylalkyl group having 15 carbon atoms or less,

Z ¹ is each independent,

At least two of Z ¹ are structures represented by the general formula (Z1-1),

In the general formula (Z1-1), Or it is a ring made by condensing at least two of these,

X belonging to Z ¹ and O adjacent to Z ¹ are connected by a linker,

If Z ¹ that is not a structure represented by the general formula (Z1-1) exists, Z ¹ that is not the structure is H or a structure represented by the general formula (Z1-S),

Q ^S1 in the general formula (Z1-S) is each independently a substituted or unsubstituted, straight-chain or branched alkyl group having 1 to 9 carbon atoms,

A substituted or unsubstituted aryl group with 15 carbon atoms or less, or

Represents a substituted or unsubstituted arylalkyl group having 15 carbon atoms or less.)

Additionally, silsesquioxane derivatives represented by the general formula AA-D2 include all geometric isomers within the scope of the general formula AA-D2. For example, as a geometric isomer represented by the general formula AA-D2, a pair of R ¹ and OZ ¹ bonded to Si exist in different directions of bonding to the ring plane, so the sil represented by the general formula AA-D2 Sesquioxane derivatives include these.

The description of R ¹ in the general formula AA-D2 is omitted because it overlaps with the description of R ¹ in the general formula AA-D1. Accordingly, the description of R ¹ in the general formula AA-D1 can also be treated as an explanation of R ¹ in the general formula AA-D2. Therefore, for example, R ¹ is preferably a methyl group, ethyl group, isobutyl group, isooctyl group, trifluoropropyl group, or phenyl group, and more preferably a phenyl group.

It is a structure in which at least two of Z ¹ are represented by the general formula (Z1-1). In other words, out of four Z ^1s , two may be represented by the general formula (Z1-1), three may be represented by the general formula (Z1-1), and four may be represented by the general formula (Z1-1). Any structure that works is fine.

Regarding Z ¹ , It is a substituted heterocycle, or a ring made by condensing at least two of these rings. The explanation of Accordingly, the explanation of X of general formula (Z1-1) in general formula AA-D1 can also be treated as the explanation of Therefore, it is preferable that From the viewpoint of difficulty in production, an unsubstituted aromatic ring is more preferable.

A linking group ^{that connects} I can hear it. Additionally, each connecting group may be independent. In other words, each connector may have a unique structure.

(In the formula, Q ¹ is each independently a substituted or unsubstituted, straight-chain or branched alkyl group having 1 to 9 carbon atoms,

A substituted or unsubstituted aryl group with 15 carbon atoms or less, or

Represents a substituted or unsubstituted arylalkyl group having 15 carbon atoms or less,

n is an integer from 0 to 8,

Q ² is a single bond, substituted or unsubstituted, straight-chain or branched alkylene group, substituted or unsubstituted arylene group, or It is a group in which the adjacent carbon is substituted with a hetero atom,

Si, shown at the end, is connected to O adjacent to Z ¹ , and Q ² , shown at the end, is connected to X.)

“Q ² shown at the end is connected to X” means that when Q ² shown at the end is a single bond, Si adjacent to ^{Q 2 shown} at the end is connected to In the case where the carbon adjacent to

When the linking group is a substituted or unsubstituted, straight-chain or branched alkylene group, the description of the alkylene group as the linking group is the description of the alkylene group (specifically, the substituted or unsubstituted, straight-chain or branched alkylene group) of the general formula AA-D1. It is omitted because it is redundant. Accordingly, the description of the alkylene group of the general formula AA-D1 can also be treated as an explanation of this alkylene group (that is, the alkylene group of the general formula AA-D2).

When the linking group is a substituted or unsubstituted arylene group, the description of the arylene group as the linking group is omitted because it overlaps with the description of the arylene group (specifically, the substituted or unsubstituted arylene group) of the general formula AA-D1. Accordingly, the description of the arylene group of the general formula AA-D1 can also be treated as an explanation of this arylene group (that is, the arylene group of the general formula AA-D2).

Regarding the linking group represented by structural formula (C), the description of Q ¹ is omitted because it overlaps with the description of R ¹ . In this way, the description of R ¹ can also be treated as the description of Q ¹ . Since there is a specific most suitable embodiment for Q ¹ , a description of the most suitable embodiment is added. Specifically, Q ¹ is preferably a methyl group, ethyl group, isopropyl group, isobutyl group, sec-butyl group, tert-butyl group, or phenyl group.

n is an integer from 0 to 8. n is preferably 5 or less, more preferably 3 or less, and even more preferably 1 or less, that is, 0 or 1, for the reason that the coefficient of linear expansion (CTE) of polyimide (for example, polyimide film) can be lowered.

Regarding the linking group represented by structural formula (C), the alkylene group (specifically, substituted or unsubstituted, straight-chain or branched alkylene group) of Q ² is described as the alkylene group (specifically, substituted or unsubstituted) of general formula AA-D1. It is omitted because it overlaps with the description of (cyclic, straight-chain, or branched alkylene group). Accordingly, the description of the alkylene group of general formula AA-D1 can also be treated as the description of the alkylene group of Q ² .

Regarding the linking group represented by structural formula (C), the description of the arylene group (specifically, the substituted or unsubstituted arylene group) of Q ² is that of the arylene group (specifically, the substituted or unsubstituted arylene group) of the general formula AA-D1. It is omitted because it is redundant with the explanation. Accordingly, the description of the arylene group of general formula AA-D1 can also be treated as the description of the arylene group of Q ² .

Regarding the linking group represented by structural formula (C), Q ² is a group in which the carbon adjacent to Specific examples of an alkylene group (e.g., methylene group, ethylene group, n-propylene group, n-butylene group, tert-butylene group, n-pentylene group, n-hexylene group, n-heptylene group, n-octylene group) A group in which the carbon constituting (specifically, the carbon adjacent to X) is substituted with a hetero atom can be mentioned. Among them, an n-butylene group, that is, a group in which the carbon adjacent to Also, in this case, the number of carbon atoms of this group (i.e. Q ² ) is 3.

Regarding the linking group represented by structural formula (C), Q ² is a hetero atom, for example, a nitrogen atom, an oxygen atom, or a sulfur atom. Among these, an oxygen atom and a sulfur atom are preferable, and an oxygen atom is more preferable.

As the linking group, a carbonyl group is preferable. When the linking group is a carbonyl group, the following structure is preferable as the structure represented by general formula (Z1-1). That is, when the linking group is a carbonyl group, Z ¹ preferably has the following structure.

Z ¹ , which is not a structure represented by the general formula (Z1-1), is H, that is, a hydrogen atom, or a structure represented by the general formula (Z1-S). If Z ¹ is H, gelation of the polyamic acid solution may easily occur. For the reason that gelation of the polyamic acid solution can be suppressed, the structure represented by the general formula (Z1-S) is preferable.

Regarding Q ^S1 in the general formula (Z1-S), the description of Q ^S1 is omitted because it overlaps with the description of R ¹ . In this way, the description of R ¹ can also be treated as the description of Q ^S1 . Since there is a specific most suitable embodiment for Q ^S1 , a description of the most suitable embodiment is added. Specifically, Q ^S1 is preferably a methyl group, ethyl group, or phenyl group from the viewpoint of raw material availability.

Regarding the specific combination of four Z ^1s , it is preferable that the four Z ^1s have a structure represented by the general formula (Z1-1).

The silsesquioxane derivative represented by the general formula AA-D2 can be produced, for example, based on the method described in the literature listed in the description of the production of the silsesquioxane derivative represented by the general formula AA-D1.

For example, based on these documents, a compound was prepared in which all Z ¹ in the general formula AA-D2 is a hydrogen atom or a sodium atom, and this compound (i.e., H or Na as Z ¹ and O adjacent to Z ¹ was prepared) A silsesquioxane derivative represented by the general formula AA-D2 can be produced by the procedure of reacting a compound having a silanol group (a compound having a silanol group) with an acid chloride having an acid anhydride group, such as trimellitic anhydride chloride. In addition, in the general formula AA-D2, compounds in which all Z ¹ is a hydrogen atom can also be obtained as a commercial product (for example, SO1460 manufactured by Hybrid Plastics).

Instead of this procedure, for example, a compound in the general formula AA-D2 is prepared in which all Z ¹ 's are hydrogen atoms or sodium atoms, and this compound (i.e., a compound containing H or Na as Z ¹ and O adjacent to Z ¹ General formula AA is obtained by reacting a compound having a silanol group) with an organodichlorosilane having a SiH group, such as methyldichlorosilane, and reacting the product (i.e., a product having a SiH group) with a compound having an acid anhydride group. A silsesquioxane derivative represented by -D1 can also be prepared.

In addition, a compound in which all Z ¹ in the general formula AA-D2 is a hydrogen atom or a sodium atom is prepared, and this compound (i.e., a compound having a silanol group containing H or Na as Z ¹ and O adjacent to Z ¹ A silsesquioxane derivative represented by the general formula AA-D1 can also be produced by a ring closure reaction (end capping reaction) between a compound) and a dichlorosilane derivative having an acid anhydride group.

Prepare a compound in which all Z ¹ 's in the general formula AA-D2 are hydrogen atoms or sodium atoms, and this compound (i.e., a compound having a silanol group containing H or Na as Z ¹ and O adjacent to Z ¹ ) A substance represented by the general formula AA-D2 is carried out by reacting an organochlorosilane having a SiH group, such as dimethylchlorosilane, and reacting the product (i.e., a product having a SiH group) with a compound having an acid anhydride group. Sesquioxane derivatives can also be prepared.

The reaction between a compound having a silanol group (i.e., a compound having a silanol group containing H as Z ¹ and O adjacent to Z ¹ ) and an acid chloride having an acid anhydride group such as trimellitic anhydride chloride, or a SiH group Prior to reaction with the organochlorosilane, a portion of the silanol group may be capped. For capping, a compound having a silanol group can be reacted with, for example, a triorganochlorosilane such as triphenylchlorosilane. In the reaction between a product having a SiH group and a compound having an acid anhydride group, hydrosilylation can be used, for example. That is, a reaction in which a product having a SiH group is added to an unsaturated bond such as a carbon-carbon double bond along with cleavage of the Si-H bond can be used. When hydrosilylation is used, the compound having an acid anhydride group may have an unsaturated bond such as a carbon-carbon double bond (eg, a vinyl group). On the other hand, in the reaction between a product having a SiH group and a compound having an acid anhydride group, there is a coupling reaction, specifically, a coupling reaction between a product having a SiH group and an aryl halide using a noble metal catalyst such as ruthenium, platinum, palladium, and rhodium. You can also use . When using a coupling reaction, a compound having an acid anhydride group or a compound having a functional group that can be converted to an acid anhydride group may have an aryl halide structure. Examples of functional groups that can be converted to acid anhydride groups include diester groups.

In addition, needless to say, this description (specifically, a description of the production of silsesquioxane derivatives represented by the general formula AA-D2, including descriptions of various reactions) contains silsesquioxane derivatives with structures other than the general formula AA-D2. It can also be appropriately treated as an explanation for producing sesquioxane derivatives.

The silsesquioxane derivative may, for example, have a structure represented by the following general formula (hereinafter sometimes referred to as “general formula AA-C1”).

(In the formula, R ¹ is each independently a substituted or unsubstituted, straight-chain or branched alkyl group having 1 to 9 carbon atoms,

A substituted or unsubstituted aryl group with 15 carbon atoms or less, or

Represents a substituted or unsubstituted arylalkyl group having 15 carbon atoms or less,

Z ¹ is each independent,

At least two of Z ¹ are structures represented by the general formula (Z1-1),

In the general formula (Z1-1), Or it is a ring made by condensing at least two of these,

X belonging to Z ¹ and O adjacent to Z ¹ are connected by a linker,

If Z ¹ that is not a structure represented by the general formula (Z1-1) exists, Z ¹ that is not the structure is H or a structure represented by the general formula (Z1-S),

Q ^S1 in the general formula (Z1-S) is each independently a substituted or unsubstituted, straight-chain or branched alkyl group having 1 to 9 carbon atoms,

A substituted or unsubstituted aryl group with 15 carbon atoms or less, or

Represents a substituted or unsubstituted arylalkyl group having 15 carbon atoms or less.)

Additionally, silsesquioxane derivatives represented by the general formula AA-C1 include all geometric isomers within the scope of the general formula AA-C1. For example, as a geometric isomer represented by the general formula AA-C1, a pair of R ¹ and OZ ¹ bonded to Si exist in different directions of bonding to the ring plane, so the sil represented by the general formula AA-C1 Sesquioxane derivatives include these.

The description of R ¹ in the general formula AA-C1 is omitted because it overlaps with the description of R ¹ in the general formula AA-D1. Accordingly, the description of R ¹ of the general formula AA-D1 can also be treated as an explanation of R ¹ of the general formula AA-C1. Therefore, for example, R ¹ is preferably a methyl group, ethyl group, isobutyl group, isooctyl group, trifluoropropyl group, or phenyl group, and more preferably a phenyl group.

It is a structure in which at least two of Z ¹ are represented by the general formula (Z1-1). That is, a structure in which two of the three Z ^1s are represented by the general formula (Z1-1) may be sufficient, and a structure in which three Z 1s are represented by the general formula (Z1-1) may be used.

Regarding Z ¹ , It is a substituted heterocycle, or a ring made by condensing at least two of these rings. The explanation of X in general formula (Z1-1) in general formula AA-C1 is omitted because it overlaps with the explanation of Accordingly, the explanation of X of general formula (Z1-1) in general formula AA-D1 can also be treated as the explanation of Therefore, it is preferable that From the viewpoint of difficulty in production, an unsubstituted aromatic ring is more preferable.

A linking group ^{that connects} I can hear it. Additionally, each connecting group may be independent. In other words, each connector may have a unique structure.

(In the formula, Q ¹ is each independently a substituted or unsubstituted, straight-chain or branched alkyl group having 1 to 9 carbon atoms,

A substituted or unsubstituted aryl group with 15 carbon atoms or less, or

Represents a substituted or unsubstituted arylalkyl group having 15 carbon atoms or less,

n is an integer from 0 to 8,

Q ² is a single bond, substituted or unsubstituted, straight-chain or branched alkylene group, substituted or unsubstituted arylene group, or It is a group in which the adjacent carbon is substituted with a hetero atom,

Si, shown at the end, is connected to O adjacent to Z ¹ , and Q ² , shown at the end, is connected to X.)

“Q ² shown at the end is connected to X” means that when Q ² shown at the end is a single bond, Si adjacent to ^{Q 2 shown} at the end is connected to In the case where the carbon adjacent to

The description of the connecting group is omitted because it overlaps with the description of the connecting group of general formula AA-D2. Accordingly, the description of the linking group of general formula AA-D2 can also be treated as the explanation of the linking group of general formula AA-C1. Therefore, for example, a carbonyl group is preferred as the linking group. When the linking group is a carbonyl group, the following structure is preferable as the structure represented by general formula (Z1-1). That is, when the linking group is a carbonyl group, Z ¹ preferably has the following structure.

Z ¹ , which is not a structure represented by the general formula (Z1-1), is H, that is, a hydrogen atom, or a structure represented by the general formula (Z1-S). If Z ¹ is H, gelation of the polyamic acid solution may easily occur. For the reason that gelation of the polyamic acid solution can be suppressed, the structure represented by the general formula (Z1-S) is preferable.

Regarding Q ^S1 in the general formula (Z1-S), the description of Q ^S1 is omitted because it overlaps with the description of R ¹ . In this way, the description of R ¹ can also be treated as the description of Q ^S1 . Since there is a specific most suitable embodiment for Q ^S1 , a description of the most suitable embodiment is added. Specifically, Q ^S1 is preferably a methyl group, ethyl group, or phenyl group from the viewpoint of raw material availability.

Regarding the specific combination of three Z ¹ , it is preferable that two of Z ¹ have the following structures and one has the structure represented by the general formula (Z1-S).

The silsesquioxane derivative represented by the general formula AA-C1 can be prepared by, for example, the same procedures as those described in the general formula AA-D2, except that all Z ^1s in the general formula AA-C1 are hydrogen atoms. It can be manufactured. Compounds in which all Z ^1s in the general formula AA-C1 are hydrogen atoms can be produced, for example, based on the methods described in the following documents.

Chemistry Letters, 2014, Vol. 43, No. 10, pp. 1532-1534

In addition, in the general formula AA-C1, compounds in which all Z ¹ is a hydrogen atom can also be obtained as commercial products (for example, SO1450 or SO1458 manufactured by Hybrid Plastics).

The silsesquioxane derivative may, for example, have a structure represented by the following general formula (hereinafter sometimes referred to as “general formula AA-Q1”).

(In the formula, Z ¹ is each independent,

At least two of Z ¹ are structures represented by the general formula (Z1-1),

In the general formula (Z1-1), Or it is a ring made by condensing at least two of these,

X belonging to Z ¹ and O adjacent to Z ¹ are connected by a linker,

If Z ¹ that is not a structure represented by the general formula (Z1-1) exists, Z ¹ that is not the structure is H or a structure represented by the general formula (Z1-S),

Q ^S1 in the general formula (Z1-S) is each independently a substituted or unsubstituted, straight-chain or branched alkyl group having 1 to 9 carbon atoms,

A substituted or unsubstituted aryl group with 15 carbon atoms or less, or

Represents a substituted or unsubstituted arylalkyl group having 15 carbon atoms or less.)

It is a structure in which at least two of Z ¹ are represented by the general formula (Z1-1). All eight Z ^1s may have this structure, but it is preferable that 2 to 6 of the 8 Z ^1s have this structure, more preferably 2 to 4 have this structure, and 2 or 3 have this structure. It is more desirable.

Regarding Z ¹ , It is a substituted heterocycle, or a ring made by condensing at least two of these rings. The explanation of X in general formula (Z1-1) in general formula AA-Q1 is omitted because it overlaps with the explanation of Accordingly, the explanation of X of general formula (Z1-1) in general formula AA-D1 can also be treated as the explanation of Therefore, it is preferable that From the viewpoint of difficulty in production, an unsubstituted aromatic ring is more preferable.

A linking group ^{that connects} You can raise your flag. Additionally, each connecting group may be independent. In other words, each connector may have a unique structure.

(In the formula, Q ¹ is each independently a substituted or unsubstituted, straight-chain or branched alkyl group having 1 to 9 carbon atoms,

A substituted or unsubstituted aryl group with 15 carbon atoms or less, or

Represents a substituted or unsubstituted arylalkyl group having 15 carbon atoms or less,

n is an integer from 0 to 8,

Q ² is a single bond, substituted or unsubstituted, straight-chain or branched alkylene group, substituted or unsubstituted arylene group, or It is a group in which the adjacent carbon is substituted with a hetero atom,

Si, shown at the end, is connected to O adjacent to Z ¹ , and Q ² , shown at the end, is connected to X.)

“Q ² shown at the end is connected to X” means that when Q ² shown at the end is a single bond, Si adjacent to ^{Q 2 shown} at the end is connected to In the case where the carbon adjacent to

The description of the connecting group is omitted because it overlaps with the description of the connecting group of general formula AA-D2. Accordingly, the description of the linking group of general formula AA-D2 can also be treated as the explanation of the linking group of general formula AA-Q1.

Z ¹ , which is not a structure represented by the general formula (Z1-1), is H, that is, a hydrogen atom, or a structure represented by the general formula (Z1-S). If Z ¹ is H, gelation of the polyamic acid solution may easily occur. For the reason that gelation of the polyamic acid solution can be suppressed, the structure represented by the general formula (Z1-S) is preferable.

Regarding Q ^S1 in the general formula (Z1-S), the description of Q ^S1 is omitted because it overlaps with the description of R ¹ in the general formula AA-D1. Accordingly, the description of R ¹ in the general formula AA-D1 can also be treated as the description of Q ^S1 . Since there is a specific most suitable embodiment for Q ^S1 , a description of the most suitable embodiment is added. Specifically, Q ^S1 is preferably a methyl group, ethyl group, or phenyl group from the viewpoint of raw material availability.

The silsesquioxane derivative represented by the general formula AA-Q1 can be prepared by, for example, the same procedures as those described in the general formula AA-D2, except that all Z ^1s in the general formula AA-Q1 are hydrogen atoms. It can be manufactured. The compound in which all Z ¹ in the general formula AA-Q1 is a hydrogen atom is obtained by protonating the tetramethylammonium salt corresponding to the compound in which all Z ¹ is a hydrogen atom using an acid, for example, based on the method described in the following document. It can be manufactured.

Chemistry Letters, 2018, Vol. 47, no. 12, pp. 1530-1533

Additionally, in the general formula AA-Q1, tetramethylammonium salts corresponding to compounds in which all Z ¹ are hydrogen atoms can also be obtained as commercial products (for example, MS0860 from Hybrid Plastics).

Examples of silsesquioxane derivatives with random structures will be described later.

Silsesquioxane derivatives may have two or more amino groups. If the silsesquioxane derivative has two or more amino groups, it may react with carboxylic acids. The number of amino groups per molecule of the silsesquioxane derivative may be, for example, 3 or more, 4 or more, 5 or more, or 6 or more. The number of amino groups per molecule may be, for example, 10 or less, or 8 or less. In particular, when the silsesquioxane derivative has a basket-like structure, the number of amino groups per molecule is preferably, for example, 2 or more and 8 or less. On the other hand, when the silsesquioxane derivative has a random structure, the number of amino groups per molecule is preferably 2 to 10, and more preferably 2.5 to 6. If the number of amino groups is within this range, the resulting polyimide chain is crosslinked appropriately, so the toughness of the polyimide film can be further improved.

Additionally, when the silsesquioxane derivative has two or more amino groups, it does not have the two or more acid anhydride groups described above.

Each amino group preferably has a linking group that connects the amino group to Si that is closest in bonding to the amino group among the Si constituting the silsesquioxane derivative. Since the description of the linking group is explained in detail in the silsesquioxane derivative represented by the general formula AM-D1 described later, the description is limited here to avoid duplication. Examples of the linking group include the structure described by Z ² in the general formula AM-D1 described later. That is, it is a linking group that connects protons (an amino group and a proton of Si that is bond-closest to the amino group among Si constituting the silsesquioxane derivative), such as a substituted or unsubstituted, straight-chain or branched alkylene group, or a substituted or unsubstituted alkylene group. Examples include an arylene group, a group represented by the structural formula (CS) described later, an ester group (i.e., an ester bond), an amide group (i.e., an amide bond), and any combination of two or more thereof. In addition, when the amino group is bonded to the ring represented by Y (see general formula AM-D1 described later), the linking group may further have a ring represented by Y. That is, in this case, the linking group is a substituted or unsubstituted, straight-chain or branched alkylene group, a substituted or unsubstituted arylene group, a group represented by the structural formula (CS) described later, an ester group (i.e., ester bond), and an amide group. (i.e., amide bond) or any combination of two or more thereof, and may further have a ring represented by Y. Here, when Y is a substituted or unsubstituted aromatic ring, an amino group may be bonded to the substituted or unsubstituted aromatic ring. Additionally, each connecting group may be independent. In other words, each connector may have a unique structure.

It is preferable that the linking groups each independently have a substituted or unsubstituted aromatic ring bonded to an amino group. This is because, compared to the case where the linking group has an aliphatic ring instead of an aromatic ring, yellowing of the polyimide (for example, polyimide film) under high temperature conditions can be further suppressed. The description of the substituted or unsubstituted aromatic ring is explained in detail in the silsesquioxane derivative represented by the general formula AM-D1 described later, so it is omitted here to avoid duplication.

The silsesquioxane derivative may, for example, have a structure represented by the following general formula (hereinafter sometimes referred to as “general formula AM-D1”).

(In the formula, R ¹ is each independently a substituted or unsubstituted, straight-chain or branched alkyl group having 1 to 9 carbon atoms,

A substituted or unsubstituted aryl group with 15 carbon atoms or less, or

Represents a substituted or unsubstituted arylalkyl group having 15 carbon atoms or less,

Q ¹ is each independently a substituted or unsubstituted, straight-chain or branched alkyl group having 1 to 9 carbon atoms,

A substituted or unsubstituted aryl group with 15 carbon atoms or less, or

Represents a substituted or unsubstituted arylalkyl group having 15 carbon atoms or less,

Z ² is each independently a structure represented by the general formula (Z2-1) or a structure represented by the general formula (Z2-2),

Y in general formula (Z2-1) is a substituted or unsubstituted aromatic ring, a substituted or unsubstituted aliphatic ring with 4 to 10 carbon atoms, or a heterocycle in which at least one carbon constituting these rings is substituted with a hetero atom, Or it is a ring made by condensing at least two of these,

Y belonging to Z ² and Si adjacent to Z ² may be connected by a single bond or may be connected by a linking group,

The amino group belonging to general formula (Z2-2) and Si adjacent to Z ² are connected by a linking group.)

Additionally, silsesquioxane derivatives represented by the general formula AM-D1 include all geometric isomers within the scope of the general formula AM-D1. For example, as a geometric isomer represented by the general formula AM-D1, a pair of Q ¹ and Z ² bonded to Si exist in different geometrical isomers in the direction of bonding to the ring plane, and are represented by the general formula AM-D1. Sesquioxane derivatives include these.

The description of R ¹ in the general formula AM-D1 is omitted because it overlaps with the description of R ¹ in the general formula AA-D1. Accordingly, the description of R ¹ of the general formula AA-D1 can also be treated as an explanation of R ¹ of the general formula AM-D1. Therefore, for example, R ¹ is preferably a methyl group, ethyl group, isobutyl group, isooctyl group, trifluoropropyl group, or phenyl group, and more preferably a phenyl group.

The description of Q ¹ is omitted because it overlaps with the description of R ¹ . In this way, the description of R ¹ can also be treated as the description of Q ¹ . Since there is a specific most suitable embodiment for Q ¹ , a description of the most suitable embodiment is added. Specifically, Q ¹ is preferably a methyl group, an ethyl group, or a phenyl group, and a methyl group is more preferable because the difficulty of production is relatively low.

Regarding Z ² , Y in the general formula (Z2-1) is a substituted or unsubstituted aromatic ring, a substituted or unsubstituted aliphatic ring having 4 to 10 carbon atoms, and at least one of the carbons constituting these rings is a hetero atom. It is a substituted heterocycle, or a ring made by condensing at least two of these rings. The explanation of Y in general formula (Z2-1) in general formula AM-D1 is omitted because it overlaps with the explanation of X in general formula (Z1-1) in general formula AA-D1. Accordingly, the explanation of Therefore, for the reason that yellowing of polyimide (for example, polyimide film) can be further suppressed under high temperature conditions, for example, around 400°C, it is preferable that Y is a substituted or unsubstituted aromatic ring. From the viewpoint of difficulty in production, an unsubstituted aromatic ring is more preferable.

Y belonging to Z ² and Si adjacent to Z ² may be connected by a single bond or may be connected by a linking group. As a linking group connecting the two, for example, a substituted or unsubstituted, straight-chain or branched alkylene group, a substituted or unsubstituted arylene group, a group represented by the following structural formula (CS), an ester group (i.e., an ester bond), an amide group (i.e. , amide bond) and any combination of two or more thereof. Additionally, each connecting group may be independent. In other words, each connector may have a unique structure.

(In the formula, Q ¹ is each independently a substituted or unsubstituted, straight-chain or branched alkyl group having 1 to 9 carbon atoms,

A substituted or unsubstituted aryl group with 15 carbon atoms or less, or

Represents a substituted or unsubstituted arylalkyl group having 15 carbon atoms or less,

n is an integer from 0 to 8,

Q ² is adjacent to Y constituting a single bond, a substituted or unsubstituted, straight-chain or branched alkylene group, a substituted or unsubstituted arylene group, or an alkylene group (specifically, a substituted or unsubstituted, straight-chain or branched alkylene group). is a group in which the carbon is substituted with a hetero atom,

The O shown at the end is connected to Si adjacent to Z ² , and the Q ² shown at the end is connected to Y.)

“Q ² shown at the end is connected to Y” means that when Q ² shown at the end is a single bond, Si adjacent to Q ² shown at the end is connected to Y, and Q ² shown at the end is an alkylene group, arylene group, or alkylene group. When the carbon adjacent to Y constituting the group is a group substituted with a hetero atom, it means that the alkylene group, arylene group, or group in which the carbon adjacent to Y constituting the alkylene group is substituted with a hetero atom is connected to Y.

The description of the connecting group in the general formula AM-D1 is omitted because it overlaps with the description of the connecting group in the general formula AA-D1. Accordingly, the description of the linking group in the general formula AA-D1 can also be treated as a description of the linking group in the general formula AM-D1.

Therefore, for example, as the linking group, a combination of a substituted or unsubstituted arylene group and an amide group is preferable, and a combination of a p-phenylene group and an amide group is more preferable. Specifically, the following structure is preferable. Additionally, the structural formula below indicates that the p-phenylene group is bonded to Si. It indicates that the amide group is bonded to Y. In other words, it indicates that the carbon constituting the amide group is bonded to Y.

When both (that is, Y belonging to Z ² and Si adjacent to Z ² ) are connected by this linking group, Z ² preferably has the following structure. In this structure, the position of the amino group may be the ortho position, the meta position, or the para position. Among them, the para position is preferable.

Both (i.e., Y belonging to Z ² and Si adjacent to Z ² ) are preferably connected by a single bond. This is because the two are connected by a single bond, so that yellowing of polyimide (for example, polyimide film) under high temperature conditions can be further suppressed.

When both are connected by a single bond, the following structure is preferable as the structure represented by general formula (Z2-1). That is, when both are connected by a single bond, Z ² preferably has the following structure. In this structure, the position of the amino group may be the ortho position, the meta position, or the para position. Among them, the para position is preferable.

That is, Z ² preferably has the following structure.

Regarding Z ² , the amino group belonging to the general formula (Z2-2) and Si adjacent to Z ² are connected by a linking group. As a linking group connecting the two, for example, a substituted or unsubstituted, straight-chain or branched alkylene group, a substituted or unsubstituted arylene group, a group represented by the above-mentioned structural formula (CS), an ester group (i.e., an ester bond), an amide group ( That is, amide bond) and any combination of two or more thereof. Additionally, each connecting group may be independent. In other words, each connector may have a unique structure.

The description of the linking group of general formula (Z2-2) in general formula AM-D1 is omitted because it overlaps with the description of the linking group in general formula AA-D1. Accordingly, the description of the linking group in the general formula AA-D1 can also be treated as an explanation of the linking group of the general formula (Z2-2) in the general formula AM-D1. Since there is a specific most suitable example specific to the linking group of the general formula (Z2-2) in the general formula AM-D1, a description of the most suitable specific example is added. Specifically, the linking group of general formula (Z2-2) in general formula AM-D1 is preferably a substituted or unsubstituted, straight-chain or branched alkylene group, and has 6 or less carbon atoms for the reason that the difficulty of production is relatively low. An unsubstituted straight-chain alkylene group is more preferable, and an n-propylene group, that is, a trimethylene group, is more preferable.

It is preferable that both Z ² have a structure represented by the general formula (Z2-1), or that both Z ² have a structure represented by the general formula (Z2-2).

The silsesquioxane derivative represented by the general formula AM-D1 can be produced, for example, based on the method described in the literature listed in the description of the production of the silsesquioxane derivative represented by the general formula AA-D1. For example, it can be produced in the same manner as the procedure described in general formula AA-D1, except that a compound having an amino group is used instead of the compound having an acid anhydride group. Additionally, in compounds having an amino group, the amino group may be protected.

In addition, among the silsesquioxane derivatives represented by the general formula AM-D1, it is described that the following silsesquioxane derivatives used in the examples described later were manufactured in Japanese Patent Application Laid-Open No. 2006-265243.

The silsesquioxane derivative may, for example, have a structure represented by the following general formula (hereinafter sometimes referred to as “general formula AM-D2”).

(In the formula, R ¹ is each independently a substituted or unsubstituted, straight-chain or branched alkyl group having 1 to 9 carbon atoms,

A substituted or unsubstituted aryl group with 15 carbon atoms or less, or

Represents a substituted or unsubstituted arylalkyl group having 15 carbon atoms or less,

Z ² is each independent,

At least two of Z ² are structures represented by the general formula (Z2-1) or structures represented by the general formula (Z2-2),

Y in general formula (Z2-1) is a substituted or unsubstituted aromatic ring, a substituted or unsubstituted aliphatic ring with 4 to 10 carbon atoms, or a heterocycle in which at least one carbon constituting these rings is substituted with a hetero atom, Or it is a ring made by condensing at least two of these,

Y belonging to Z ² and O adjacent to Z ² are connected by a linker,

The amino group belonging to general formula (Z2-2) and O adjacent to Z ² are connected by a linking group,

If there is a Z ^{2 that is neither a structure represented by the general formula (Z2-1) nor a structure represented by the general formula (Z2-2), Z 2 that} is not one of these structures is expressed as H or the general formula (Z2-S) The structure is displayed,

Q ^S1 in the general formula (Z2-S) is each independently a substituted or unsubstituted, straight-chain or branched alkyl group having 1 to 9 carbon atoms,

A substituted or unsubstituted aryl group with 15 carbon atoms or less, or

Represents a substituted or unsubstituted arylalkyl group having 15 carbon atoms or less.)

Additionally, silsesquioxane derivatives represented by the general formula AM-D2 include all geometric isomers within the scope of the general formula AM-D2. For example, as a geometric isomer represented by the general formula AM-D2, a pair of R ¹ and OZ ² bonded to Si exist in different directions of bonding to the ring plane, so the sil represented by the general formula AM-D2 Sesquioxane derivatives include these.

The description of R ¹ in the general formula AM-D2 is omitted because it overlaps with the description of R ¹ in the general formula AA-D1. Accordingly, the description of R ¹ in the general formula AA-D1 can also be treated as the description of R ¹ in the general formula AM-D2. Therefore, for example, R ¹ is preferably a methyl group, ethyl group, isobutyl group, isooctyl group, trifluoropropyl group, or phenyl group, and more preferably a phenyl group.

At least two of Z ² are each independently a structure represented by the general formula (Z2-1) or a structure represented by the general formula (Z2-2). In other words, two of the four Z ^2s may each independently have a structure represented by the general formula (Z2-1) or a structure represented by the general formula (Z2-2), and three of them may each independently have the general formula (Z2-1). A structure represented by or a structure represented by the general formula (Z2-2) may be used, or the four structures may each be independently represented by the general formula (Z2-1) or a structure represented by the general formula (Z2-2).

Regarding Z ² , Y in the general formula (Z2-1) is a substituted or unsubstituted aromatic ring, a substituted or unsubstituted aliphatic ring having 4 to 10 carbon atoms, and at least one of the carbons constituting these rings is a hetero atom. It is a substituted heterocycle, or a ring made by condensing at least two of these rings. The explanation of Y in general formula (Z2-1) in general formula AM-D2 is omitted because it overlaps with the explanation of X in general formula (Z1-1) in general formula AA-D1. Accordingly, the explanation of Therefore, it is preferable that From the viewpoint of difficulty in production, an unsubstituted aromatic ring is more preferable.

As a linking group connecting Y belonging to Z ² and O adjacent to Z ² , for example, a substituted or unsubstituted, straight-chain or branched alkylene group, a carbonyl group, a substituted or unsubstituted arylene group, or a group represented by the following structural formula (C) I can hear it. Additionally, each connecting group may be independent. In other words, each connector may have a unique structure.

(In the formula, Q ¹ is each independently a substituted or unsubstituted, straight-chain or branched alkyl group having 1 to 9 carbon atoms,

A substituted or unsubstituted aryl group with 15 carbon atoms or less, or

Represents a substituted or unsubstituted arylalkyl group having 15 carbon atoms or less,

n is an integer from 0 to 8,

Q ² is Y constituting a single bond, a substituted or unsubstituted, straight-chain or branched alkylene group, a substituted or unsubstituted arylene group, or an alkylene group (specifically, a substituted or unsubstituted, straight-chain or branched alkylene group) is a group in which the carbon adjacent to is substituted with a hetero atom,

Si shown at the end is connected to O adjacent to Z ² , and Q ² shown at the end is connected to Y.)

“Q ² shown at the end is connected to Y” means that when Q ² shown at the end is a single bond, Si adjacent to Q ² shown at the end is connected to Y, and Q ² shown at the end is an alkylene group, arylene group, or alkylene group. When the carbon adjacent to Y constituting the group is a group substituted with a hetero atom, it means that the alkylene group, arylene group, or group in which the carbon adjacent to Y constituting the alkylene group is substituted with a hetero atom is connected to Y.

The description of the connecting group is omitted because it overlaps with the description of the connecting group of general formula AA-D2. Accordingly, the description of the linking group of general formula AA-D2 can also be treated as the explanation of the linking group of general formula AM-D2. Therefore, for example, a carbonyl group is preferred as the linking group. When the linking group is a carbonyl group, the following structure is preferable as the structure represented by general formula (Z2-1). That is, when the linking group is a carbonyl group, Z ² preferably has the following structure. In this structure, the position of the amino group may be the ortho position, the meta position, or the para position. Among them, the para position is preferable.

In addition, as the linking group, a group represented by structural formula (C) is also preferred. When the linking group is a group represented by structural formula (C), Z ² preferably has the following structure. In this structure, the position of the amino group may be the ortho position, the meta position, or the para position. Among them, the para position is preferable.

Regarding Z ² , examples of the linking group that connects the amino group belonging to the general formula (Z2-2) and O adjacent to Z ² include the linking group of the general formula (Z2-1). That is, examples thereof include substituted or unsubstituted, straight-chain or branched alkylene groups, carbonyl groups, substituted or unsubstituted arylene groups, and groups represented by structural formula (C). Additionally, each connecting group may be independent. In other words, each connector may have a unique structure.

The description of the linking group of the general formula (Z2-2) in the general formula AM-D2 is omitted because it overlaps with the explanation of the linking group of the general formula AA-D2. Accordingly, the description of the linking group of the general formula AA-D2 can also be treated as an explanation of the linking group of the general formula (Z2-2) in the general formula AM-D2. Therefore, for example, a group represented by structural formula (C) is preferred. When the linking group is a group represented by structural formula (C), Z ² preferably has the following structure.

Z 2 , which is neither a structure represented by the general formula (Z2-1) nor a structure represented by the general formula ( ^Z2-2 ), is H, that is, a hydrogen atom, or a structure represented by the general formula (Z2-S). If Z ² is H, gelation of the polyamic acid solution may easily occur. For the reason that gelation of the polyamic acid solution can be suppressed, the structure represented by the general formula (Z2-S) is preferable.

Regarding Q ^S1 in the general formula (Z2-S), the description of Q ^S1 is omitted because it overlaps with the description of R ¹ . In this way, the description of R ¹ can also be treated as the description of Q ^S1 . Since there is a specific most suitable embodiment for Q ^S1 , a description of the most suitable embodiment is added. Specifically, Q ^S1 is preferably a methyl group, ethyl group, or phenyl group from the viewpoint of raw material availability.

Regarding the specific combination of four Z ² , a structure in which all four Z ² are represented by the general formula (Z2-1), or a structure in which all four Z ² are represented by the general formula (Z2-2) It is desirable to be

The silsesquioxane derivative represented by the general formula AM-D2 can be produced by the same procedures as those described in the general formula AA-D2, except that a compound having an amino group is used instead of the compound having an acid anhydride group. Additionally, in compounds having an amino group, the amino group may be protected.

The silsesquioxane derivative may, for example, have a structure represented by the following general formula (hereinafter sometimes referred to as “general formula AM-C1”).

(In the formula, R ¹ is each independently a substituted or unsubstituted, straight-chain or branched alkyl group having 1 to 9 carbon atoms,

A substituted or unsubstituted aryl group with 15 carbon atoms or less, or

Represents a substituted or unsubstituted arylalkyl group having 15 carbon atoms or less,

Z ² is each independent,

At least two of Z ² are each independently a structure represented by the general formula (Z2-1) or a structure represented by the general formula (Z2-2),

Y in general formula (Z2-1) is a substituted or unsubstituted aromatic ring, a substituted or unsubstituted aliphatic ring with 4 to 10 carbon atoms, or a heterocycle in which at least one carbon constituting these rings is substituted with a hetero atom, Or it is a ring made by condensing at least two of these,

Y belonging to Z ² and O adjacent to Z ² are connected by a linker,

The amino group belonging to general formula (Z2-2) and O adjacent to Z ² are connected by a linking group,

If there is a Z ^{2 that is neither a structure represented by the general formula (Z2-1) nor a structure represented by the general formula (Z2-2), Z 2 that} is not one of these structures is expressed as H or the general formula (Z2-S) The structure is displayed,

Q ^S1 in the general formula (Z2-S) is each independently a substituted or unsubstituted, straight-chain or branched alkyl group having 1 to 9 carbon atoms,

A substituted or unsubstituted aryl group with 15 carbon atoms or less, or

Represents a substituted or unsubstituted arylalkyl group having 15 carbon atoms or less.)

Additionally, silsesquioxane derivatives represented by the general formula AM-C1 include all geometric isomers within the scope of the general formula AM-C1. For example, as a geometric isomer represented by the general formula AM-C1, a pair of R ¹ and OZ ² bonded to Si have different bonding directions to the ring plane, so there is a geometric isomer represented by the general formula AM-C1. Sesquioxane derivatives include these.

The description of R ¹ in the general formula AM-C1 is omitted because it overlaps with the description of R ¹ in the general formula AA-D1. Accordingly, the description of R ¹ in the general formula AA-D1 can also be treated as a description of R 1 in the general formula AM-C1. Therefore, for example, R ¹ is preferably a methyl group, ethyl group, isobutyl group, isooctyl group, trifluoropropyl group, or phenyl group, and more preferably a phenyl group.

At least two of Z ² are each independently a structure represented by the general formula (Z2-1) or a structure represented by the general formula (Z2-2). In other words, two of the three Z ^2s may each independently have a structure represented by the general formula (Z2-1) or a structure represented by the general formula (Z2-2), and the three Z 2s may each have a structure independently expressed by the general formula (Z2-1). A structure represented by or a structure represented by the general formula (Z2-2) may be used.

Regarding Z ² , Y in the general formula (Z2-1) is a substituted or unsubstituted aromatic ring, a substituted or unsubstituted aliphatic ring having 4 to 10 carbon atoms, and at least one of the carbons constituting these rings is a hetero atom. It is a substituted heterocycle, or a ring made by condensing at least two of these rings. The explanation of Y in general formula (Z2-1) in general formula AM-C1 is omitted because it overlaps with the explanation of X in general formula (Z1-1) in general formula AA-D1. Accordingly, the explanation of Therefore, for the reason that yellowing of polyimide (for example, polyimide film) can be further suppressed under high temperature conditions, for example, around 400°C, it is preferable that Y is a substituted or unsubstituted aromatic ring. From the viewpoint of difficulty in production, an unsubstituted aromatic ring is more preferable.

A linking group connecting Y belonging to Z ² and O adjacent to Z ² , such as a substituted or unsubstituted, straight-chain or branched alkylene group, a carbonyl group, a substituted or unsubstituted arylene group, represented by the following structural formula (C) You can raise your flag. Additionally, each connecting group may be independent. In other words, each connector may have a unique structure.

(In the formula, Q ¹ is each independently a substituted or unsubstituted, straight-chain or branched alkyl group having 1 to 9 carbon atoms,

A substituted or unsubstituted aryl group with 15 carbon atoms or less, or

Represents a substituted or unsubstituted arylalkyl group having 15 carbon atoms or less,

n is an integer from 0 to 8,

Q ² is Y constituting a single bond, a substituted or unsubstituted, straight-chain or branched alkylene group, a substituted or unsubstituted arylene group, or an alkylene group (specifically, a substituted or unsubstituted, straight-chain or branched alkylene group) is a group in which the carbon adjacent to is substituted with a hetero atom,

Si shown at the end is connected to O adjacent to Z ² , and Q ² shown at the end is connected to Y.)

“Q ² shown at the end is connected to Y” means that when Q ² shown at the end is a single bond, Si adjacent to Q ² shown at the end is connected to Y, and Q ² shown at the end is an alkylene group, arylene group, or alkylene group. When the carbon adjacent to Y constituting the group is a group substituted with a hetero atom, it means that the alkylene group, arylene group, or group in which the carbon adjacent to Y constituting the alkylene group is substituted with a hetero atom is connected to Y.

The description of the connecting group is omitted because it overlaps with the description of the connecting group of general formula AA-D2. Accordingly, the description of the linking group of general formula AA-D2 can also be treated as the explanation of the linking group of general formula AM-C1. Therefore, for example, a carbonyl group is preferred as the linking group. When the linking group is a carbonyl group, the following structure is preferable as the structure represented by general formula (Z2-1). That is, when the linking group is a carbonyl group, Z ² preferably has the following structure. In this structure, the position of the amino group may be the ortho position, the meta position, or the para position. Among them, the para position is preferable.

In addition, as the linking group, a group represented by structural formula (C) is also preferred. When the linking group is a group represented by structural formula (C), Z ² preferably has the following structure. In this structure, the position of the amino group may be the ortho position, the meta position, or the para position. Among them, the para position is preferable.

Regarding Z ² , examples of the linking group that connects the amino group belonging to the general formula (Z2-2) and O adjacent to Z ² include the linking group of the general formula (Z2-1). That is, examples thereof include substituted or unsubstituted, straight-chain or branched alkylene groups, carbonyl groups, substituted or unsubstituted arylene groups, and groups represented by structural formula (C). Additionally, each connecting group may be independent. In other words, each connector may have a unique structure.

The description of the linking group of the general formula (Z2-2) in the general formula AM-C1 is omitted because it overlaps with the explanation of the linking group of the general formula AA-D2. Accordingly, the description of the linking group of general formula AA-D2 can also be treated as the explanation of the linking group of general formula (Z2-2) in general formula AM-C1. Therefore, for example, a group represented by structural formula (C) is preferred. When the linking group is a group represented by structural formula (C), Z ² preferably has the following structure.

It is preferable that at least two of Z ² have a structure represented by the general formula (Z2-1), or that at least two of Z ² have a structure represented by the general formula (Z2-2).

Z 2 , which is neither a structure represented by the general formula (Z2-1) nor a structure represented by the general formula ( ^Z2-2 ), is H, that is, a hydrogen atom, or a structure represented by the general formula (Z2-S). If Z ² is H, gelation of the polyamic acid solution may easily occur. For the reason that gelation of the polyamic acid solution can be suppressed, the structure represented by the general formula (Z2-S) is preferable.

Regarding Q ^S1 in the general formula (Z2-S), the description of Q ^S1 is omitted because it overlaps with the description of R ¹ . In this way, the description of R ¹ can also be treated as the description of Q ^S1 . Since there is a specific most suitable embodiment for Q ^S1 , a description of the most suitable embodiment is added. Specifically, Q ^S1 is preferably a methyl group, ethyl group, or phenyl group from the viewpoint of raw material availability.

Regarding the specific combination of three Z ² , it is preferable that two of Z ² have the following structures and one has the structure represented by the general formula (Z2-S). In the structure below, the position of the amino group may be an ortho position, a meta position, or a para position. Among them, the para position is preferable.

Regarding the specific combination of three Z ² , it is also preferable that two of Z ² have the following structures and one has the structure represented by the general formula (Z2-S). In the structure below, the position of the amino group may be an ortho position, a meta position, or a para position. Among them, the para position is preferable.

Regarding the specific combination of three Z ² , it is also preferable that two of Z ² have the following structures and one has the structure represented by the general formula (Z2-S).

The silsesquioxane derivative represented by the general formula AM-C1 can be produced by the same procedures as those described in the general formula AA-C1, except that a compound having an amino group is used instead of the compound having an acid anhydride group. Additionally, in compounds having an amino group, the amino group may be protected.

The silsesquioxane derivative may, for example, have a structure represented by the following general formula (hereinafter sometimes referred to as “general formula AM-Q1”).

(In the formula, Z ² is each independent,

At least two of Z ² are each independently a structure represented by the general formula (Z2-1) or a structure represented by the general formula (Z2-2),

Y in general formula (Z2-1) is a substituted or unsubstituted aromatic ring, a substituted or unsubstituted aliphatic ring with 4 to 10 carbon atoms, or a heterocycle in which at least one carbon constituting these rings is substituted with a hetero atom, Or it is a ring made by condensing at least two of these,

Y belonging to Z ² and O adjacent to Z ² are connected by a linker,

The amino group belonging to general formula (Z2-2) and O adjacent to Z ² are connected by a linking group,

If there is a Z ^{2 that is neither a structure represented by the general formula (Z2-1) nor a structure represented by the general formula (Z2-2), Z 2 that} is not one of these structures is expressed as H or the general formula (Z2-S) The structure is displayed,

Q ^S1 in the general formula (Z2-S) is each independently a substituted or unsubstituted, straight-chain or branched alkyl group having 1 to 9 carbon atoms,

A substituted or unsubstituted aryl group with 15 carbon atoms or less, or

Represents a substituted or unsubstituted arylalkyl group having 15 carbon atoms or less.)

At least two of Z ² are each independently a structure represented by the general formula (Z2-1) or a structure represented by the general formula (Z2-2). A structure in which all eight Z ^2s are independently represented by the general formula (Z2-1) or a structure in which the general formula (Z2-2) may be used is acceptable, but 2 to 6 of the 8 Z ^2s are each independently expressed by the general formula. A structure represented by (Z2-1) or a structure represented by the general formula (Z2-2) may be used, and 2 to 4 structures each independently represented by the general formula (Z2-1) or the general formula (Z2-2) may be used. ) may be used, or two or three structures may each be independently represented by the general formula (Z2-1) or structures represented by the general formula (Z2-2).

Regarding Z ² , Y in the general formula (Z2-1) is a substituted or unsubstituted aromatic ring, a substituted or unsubstituted aliphatic ring having 4 to 10 carbon atoms, and at least one of the carbons constituting these rings is a hetero atom. It is a substituted heterocycle, or a ring made by condensing at least two of these rings. The explanation of Y in general formula (Z2-1) in general formula AM-Q1 is omitted because it overlaps with the explanation of X in general formula (Z1-1) in general formula AA-D1. Accordingly, the explanation of Therefore, for the reason that yellowing of polyimide (for example, polyimide film) can be further suppressed under high temperature conditions, for example, around 400°C, it is preferable that Y is a substituted or unsubstituted aromatic ring. From the viewpoint of difficulty in production, an unsubstituted aromatic ring is more preferable.

A linking group connecting Y belonging to Z ² and O adjacent to Z ² , such as a substituted or unsubstituted, straight-chain or branched alkylene group, a carbonyl group, a substituted or unsubstituted arylene group, represented by the following structural formula (C) You can raise your flag. Additionally, each connecting group may be independent. In other words, each connector may have a unique structure.

(In the formula, Q ¹ is each independently a substituted or unsubstituted, straight-chain or branched alkyl group having 1 to 9 carbon atoms,

A substituted or unsubstituted aryl group with 15 carbon atoms or less, or

Represents a substituted or unsubstituted arylalkyl group having 15 carbon atoms or less,

n is an integer from 0 to 8,

Q ² is a single bond, a substituted or unsubstituted, straight-chain or branched alkylene group, a substituted or unsubstituted arylene group, or an alkylene group (specifically, a substituted or unsubstituted, straight-chain or branched alkylene group). It is a group in which the adjacent carbon is substituted with a hetero atom,

Si shown at the end is connected to O adjacent to Z ² , and Q ² shown at the end is connected to Y.)

“Q ² shown at the end is connected to Y” means that when Q ² shown at the end is a single bond, Si adjacent to Q ² shown at the end is connected to Y, and Q ² shown at the end is an alkylene group, arylene group, or alkylene group. When the carbon adjacent to Y constituting the group is a group substituted with a hetero atom, it means that the alkylene group, arylene group, or group in which the carbon adjacent to Y constituting the alkylene group is substituted with a hetero atom is connected to Y.

The description of the connecting group is omitted because it overlaps with the description of the connecting group of general formula AA-D2. Accordingly, the description of the linking group of general formula AA-D2 can also be treated as the explanation of the linking group of general formula AM-Q1.

Regarding Z ² , examples of the linking group that connects the amino group belonging to the general formula (Z2-2) and O adjacent to Z ² include the linking group of the general formula (Z2-1). That is, examples thereof include substituted or unsubstituted, straight-chain or branched alkylene groups, carbonyl groups, substituted or unsubstituted arylene groups, and groups represented by structural formula (C). Additionally, each connecting group may be independent. In other words, each connector may have a unique structure.

The description of the linking group of the general formula (Z2-2) in the general formula AM-Q1 is omitted because it overlaps with the explanation of the linking group of the general formula AA-D2. Accordingly, the description of the linking group of general formula AA-D2 can also be treated as the explanation of the linking group of general formula (Z2-2) in general formula AM-Q1.

Z 2 , which is neither a structure represented by the general formula (Z2-1) nor a structure represented by the general formula ( ^Z2-2 ), is H, that is, a hydrogen atom, or a structure represented by the general formula (Z2-S). If Z ² is H, gelation of the polyamic acid solution may easily occur. For the reason that gelation of the polyamic acid solution can be suppressed, the structure represented by the general formula (Z2-S) is preferable.

Regarding Q ^S1 in the general formula (Z2-S), the description of Q ^S1 is omitted because it overlaps with the description of R ¹ in the general formula AA-D1. Accordingly, the description of R ¹ in the general formula AA-D1 can also be treated as the description of Q ^S1 . Since there is a specific most suitable embodiment for Q ^S1 , a description of the most suitable embodiment is added. Specifically, Q ^S1 is preferably a methyl group, ethyl group, or phenyl group from the viewpoint of raw material availability.

The silsesquioxane derivative represented by the general formula AM-Q1 can be produced by the same procedures as those described in the general formula AA-Q1, except that a compound having an amino group is used instead of a compound having an acid anhydride group. Additionally, in compounds having an amino group, the amino group may be protected.

<Example of silsesquioxane derivative with random structure_Silsesquioxane Compound A>

An example of a silsesquioxane derivative having a random structure includes silsesquioxane compound A, which has two or more acid anhydride groups and is described below. Additionally, silsesquioxane compound A is a novel silsesquioxane compound.

The novel silsesquioxane compound A is a thiol group of condensate B, which is a thiol group-containing silsesquioxane compound, and at least one reactive group selected from a vinyl group, an alkenyl group, a cycloalkenyl group, an alkynyl group, and an acid chloride group. It is a silsesquioxane compound formed by reacting with the reactive group of dicarboxylic acid anhydride C.

Condensate B is a thiol group-containing trialkoxysilane a1 represented by the general formula: R ¹ Si(OR ² ) ₃ ,

(In the formula, R ¹ represents an organic group in which at least one hydrogen of an aliphatic hydrocarbon group, an alicyclic hydrocarbon group, or an aromatic hydrocarbon group having 1 to 8 carbon atoms is substituted with a thiol group, and R ² independently represents a hydrogen atom and 1 carbon atom. Represents ~8 aliphatic hydrocarbon group, alicyclic hydrocarbon group, or aromatic hydrocarbon group.)

It is a condensate B of trialkoxysilanes a2 without a thiol group.

Additionally, the structure of silsesquioxane compound A may be partially specified as two repeating units. That is, the novel silsesquioxane compound A preferably has structural units represented by the following general formulas (1) and (2).

(Wherein, Q ¹ represents an aliphatic hydrocarbon group, an alicyclic hydrocarbon group, or an aromatic hydrocarbon group having 1 to 8 carbon atoms, and Q ² represents a single bond, a hydrocarbon group having 1 to 8 carbon atoms, or a carbon atom of a hydrocarbon group having 1 to 8 carbon atoms. At least one of is an organic group or carbonyl group substituted with oxygen, and , one or more of the hydrogens bonded to them may be substituted with a hydrocarbon group, and 1.0≤m≤2.0 and 1.4≤n≤1.6.)

(In the formula, Q ³ represents an aliphatic hydrocarbon group, an alicyclic hydrocarbon group, or an aromatic hydrocarbon group having 1 to 8 carbon atoms, and 1.4≤n≤1.6.)

The novel silsesquioxane compound A can be suitably produced, for example, by a production method sequentially including the following steps.

General formula: thiol group-containing trialkoxysilanes a1 represented by R ¹ Si(OR ² ) ₃ ,

(In the formula, R ¹ represents an organic group in which at least one hydrogen of an aliphatic hydrocarbon group, an alicyclic hydrocarbon group, or an aromatic hydrocarbon group having 1 to 8 carbon atoms is substituted with a thiol group, and R ² independently represents a hydrogen atom and 1 carbon atom. Represents ~8 aliphatic hydrocarbon group, alicyclic hydrocarbon group, or aromatic hydrocarbon group.)

A first step of obtaining a reaction mixture x by hydrolyzing trialkoxysilanes a2 without a thiol group and water using an acidic catalyst,

A second process of removing the acidic catalyst from the reaction mixture x to obtain a reaction mixture y,

A third step of obtaining condensate B having a thiol group by mixing and condensing the reaction mixture y with a polar solvent containing a basic catalyst, and

A fourth step of reacting the condensate B with dicarboxylic anhydride C having at least one reactive group selected from vinyl, alkenyl, cycloalkenyl, alkynyl, and acid chloride groups.

In addition, a commercially available thiol group-containing silsesquioxane compound (condensate B) and a dicarboxylic acid anhydride having at least one reactive group selected from vinyl group, alkenyl group, cycloalkenyl group, alkynyl group, and acid chloride group. It can also be obtained by reacting C.

<Condensate B (silsesquioxane compound containing thiol group)>

Condensate B is a condensate of trialkoxysilanes a1 containing a thiol group and trialkoxysilanes a2 without a thiol group. As the condensate B, for example, the organic-inorganic hybrid resin Composeran SQ (product name: SQ107 or SQ109, Arakawa Chemical Industry Co., Ltd.) can be used. Alternatively, condensate B synthesized by a method including the first to third steps above can be used.

<First process>

The first step is hydrolyzing a thiol group-containing trialkoxysilane a1 represented by the general formula: R ¹ Si(OR ² ) ₃ , a thiol group-free trialkoxysilane a2, and water using an acidic catalyst. This is the process of obtaining reaction mixture x by reacting.

(In the formula, R ¹ represents an organic group in which at least one hydrogen of an aliphatic hydrocarbon group, an alicyclic hydrocarbon group, or an aromatic hydrocarbon group having 1 to 8 carbon atoms is substituted with a thiol group, and R ² independently represents a hydrogen atom and 1 carbon atom. Represents ~8 aliphatic hydrocarbon group, alicyclic hydrocarbon group, or aromatic hydrocarbon group.)

Here, “carbon number 1 to 8” modifies an aliphatic hydrocarbon group, an alicyclic hydrocarbon group and an aromatic hydrocarbon group, but in terms of the relationship with the minimum carbon number, it more accurately refers to an aliphatic hydrocarbon group with a carbon number of 1 to 8 and a carbon number of 4 to 8. refers to an alicyclic hydrocarbon group or an aromatic hydrocarbon group having 6 to 8 carbon atoms. Additionally, limitations on the number of carbon atoms such as “carbon number 1 to 8” mean the number of carbon atoms of the entire organic group including the substituent.

More specifically, in the above general formula, R ¹ is a hydrocarbon group of 1 to 8 carbon atoms having a linear or branched chain or an aliphatic ring, or at least one aromatic hydrocarbon group of 6 to 8 carbon atoms, which may have a hydrocarbon group. It represents an organic group in which hydrogen is replaced by a thiol group. As R ¹ , a straight-chain hydrocarbon group is preferable from the viewpoint of providing flexibility to the polymer chain, and an alicyclic hydrocarbon group or aromatic hydrocarbon group is preferable from the viewpoint of improving heat resistance.

R ² independently represents a hydrogen atom, a hydrocarbon group with 1 to 8 carbon atoms having a straight or branched chain, or an aliphatic ring, or an aromatic hydrocarbon group with 6 to 8 carbon atoms, which may have a hydrocarbon group. R ² is preferably an alkyl group having 1 to 4 carbon atoms from the viewpoint of reactivity in the hydrolysis reaction. In particular, a methyl group or an ethyl group is preferred.

Specific examples of thiol group-containing trialkoxysilanes a1 (hereinafter referred to as component (a1)) include 3-mercaptopropyltrimethoxysilane, 3-mercaptopropyltriethoxysilane, and 3-mercaptopropyltripropoxysilane. , 3-Mercaptopropyltributoxysilane, 1,4-dimercapto-2-(trimethoxysilyl)butane, 1,4-dimercapto-2-(triethoxysilyl)butane, 1,4 -Dimercapto-2-(tripropoxysilyl)butane, 1,4-dimercapto-2-(tributoxysilyl)butane, 2-mercaptomethyl-3-mercaptopropyltrimethoxysilane, 2 -Mercaptomethyl-3-mercaptopropyltriethoxysilane, 2-mercaptomethyl-3-mercaptopropyltripropoxysilane, 2-mercaptomethyl-3-mercaptopropyltributoxysilane, 1,2 -Dimercaptoethyltrimethoxysilane, 1,2-dimercaptoethyltriethoxysilane, 1,2-dimercaptoethyltripropoxysilane, 1,2-dimercaptoethyltributoxysilane, etc. can be mentioned, and any of the above exemplary compounds can be used alone or in appropriate combinations. Among the above exemplary compounds, 3-mercaptopropyltrimethoxysilane is particularly preferable because it has high hydrolysis reactivity and is easy to obtain.

Trialkoxysilanes a2 (hereinafter referred to as component (a2)) that do not have a thiol group include compounds represented by the general formula: R ³ Si(OR ² ) ₃ .

(In the formula, R ³ represents an aliphatic hydrocarbon group having 1 to 8 carbon atoms, an alicyclic hydrocarbon group or an aromatic hydrocarbon group, and R ² independently represents a hydrogen atom, an aliphatic hydrocarbon group having 1 to 8 carbon atoms, an alicyclic hydrocarbon group or an aromatic hydrocarbon group. It represents a hydrocarbon group.)

More specifically, R ³ represents a hydrocarbon group of 1 to 8 carbon atoms having a linear or branched chain or an aliphatic ring, or an aromatic hydrocarbon group of 6 to 8 carbon atoms which may have a hydrocarbon group. R ² is the same as described for component (a1), but may be the same or different from R ² in component (a1).

Specific examples of component (a2) include methyltrimethoxysilane, methyltriethoxysilane, ethyltrimethoxysilane, ethyltriethoxysilane, phenyltrimethoxysilane, and phenyltriethoxysilane. Component (a2) can be used individually or in combination of two or more. Since the amount of thiol groups can be adjusted by using these, the degree of crosslinking of the finally obtained polyimide can be adjusted or the ratio of inorganic components in the polyimide can be increased.

The molar ratio ([moles of a2]/[moles of a1 + moles of a2]) of trialkoxysilanes a2 in alkoxysilanes is preferably 0.1 or more and 0.7 or less, and more preferably 0.2 or more and 0.7 or less. As the molar ratio increases, the amount of thiol groups contained per molecule decreases, and as the molar ratio decreases, the amount of thiol groups increases. By falling within this range, the obtained polyimide chain is crosslinked appropriately, and the effect of improving physical properties is also sufficient.

Condensate B, which is a thiol group-containing silsesquioxane, can be obtained by hydrolyzing component (a1) and component (a2) and then condensing them. In the first step, the alkoxy group contained in component (a1) or component (a2) becomes a silanol group through a hydrolysis reaction, and alcohol is produced as a by-product.

The amount of water required for the hydrolysis reaction is preferably 0.4 to 10 in terms of a molar ratio ([number of moles of water used in the hydrolysis reaction]/[total number of moles of each alkoxy group contained in component (a1) and component (a2)]). When this molar ratio is 0.4 or more and less than 0.5, some alkoxy groups remain in the obtained thiol group-containing silsesquioxane, but adhesion to inorganic materials can be improved. Additionally, in the case of 0.5 to 10, substantially no alkoxy group remains in the obtained thiol group-containing silsesquioxane, and it is easy to produce a thick film cured product.

In addition to component (a1) and component (a2), dialkoxysilanes and/or tetraalkoxysilanes may be additionally used within a range that does not impair the effect of the present invention (for example, 50 mol% or less).

As the catalyst used in the hydrolysis reaction, a conventionally known acidic catalyst that can function as a hydrolysis catalyst can be used arbitrarily. However, since it is necessary to substantially remove the acid catalyst after the hydrolysis reaction, it is preferable that it is easy to remove. Examples of such include formic acid, which has a low boiling point and can be removed by reduced pressure, and solid acid catalysts, which can be easily removed by methods such as filtration.

Examples of solid acid catalysts include cation exchange resins, activated clay, and carbon-based solid acids. Among them, cation exchange resins are preferable because they have high catalytic activity and are easy to obtain. As the cation exchange resin, a strong acid type cation exchange resin or a weak acid type cation exchange resin can be used. As strong acid type ion exchange resins, Diaion SK series, Copper UBK series, Copper PK series, Copper HPK25/PCP series (all brand names manufactured by Mitsubishi Chemical Corporation), Amberlight IR120B, Copper IR124, Copper 200CT, Copper 252 , Amber Jet 1020, Copper 1024, Copper 1060, Copper 1220, Amberlist 15DRY, Copper 15JWET, Copper 16WET, Copper 31WET, Copper 35WET (all brand names manufactured by Organo Co., Ltd.), etc. Examples include the Aion WK series, WK40 (all brand names manufactured by Mitsubishi Chemical Corporation), Amberlight FPC3500, and IRC76 (all brand names manufactured by Organo Co., Ltd.). The type of ion exchange resin used can be arbitrarily selected depending on the reaction rate, suppression of side reactions, etc., but a strongly acidic ion exchange resin is particularly preferable from the viewpoint of reactivity.

The amount of the acid catalyst added is preferably 0.1 to 25 parts by mass, more preferably 1 to 10 parts by mass, based on a total of 100 parts by mass of component (a1) and component (a2). If it is 25 parts by mass or less, it becomes easy to remove in a later process and tends to be economically advantageous. On the other hand, if it is 0.1 part by mass or more, the reaction can proceed appropriately, and the reaction time tends not to become excessively long.

The reaction temperature and time can be set arbitrarily depending on the reactivity of component (a1) or component (a2), but is usually about 0 to 100°C, preferably 20 to 60°C and about 1 minute to 2 hours. The hydrolysis reaction can be carried out in the presence or absence of a solvent, but it is preferable not to use a solvent. When using a solvent, the type of solvent is not particularly limited, and one or more types of arbitrary solvents can be selected and used, but it is preferable to use the same solvent as the solvent used in the condensation reaction described later.

<Second process>

The second process is a process of obtaining reaction mixture y by removing the acidic catalyst from the reaction mixture x. That is, after completion of the hydrolysis reaction in the first step, it is necessary to substantially remove the acid catalyst from the system. If it is not removed, the reaction may not proceed in the condensation reaction described later, the silanol group may not be completely consumed, or the system may gel due to abnormal high molecular weight, so the desired thiol group-containing silsesquioxane (condensate) B) cannot be obtained.

The method for removing the acid catalyst can be appropriately selected from various known methods depending on the catalyst used. For example, as described above, when formic acid is used, it can be easily removed by reduced pressure, and when a solid acid catalyst is used, it can be easily removed by methods such as filtration at the end of the condensation reaction.

In addition, after the hydrolysis reaction is completed and the acid catalyst is removed from the system, or at the same time as the acid catalyst is removed, by-produced alcohol or unnecessary water may be removed by a method such as pressure reduction. Additionally, by diluting it with a solvent used in the condensation reaction after removal, it is possible to make it easier to add the hydrolysis reactant in the subsequent condensation reaction.

<Third process>

The third step is a step of obtaining condensate B having a thiol group by mixing and condensing the reaction mixture y with a polar solvent containing a basic catalyst. In the condensation reaction, water is by-produced between the above-mentioned silanol groups, and alcohol is by-produced between the silanol groups and alkoxy groups to form a siloxane bond. For the condensation reaction, any conventionally known basic catalyst that can function as a dehydration condensation catalyst can be used.

The basic catalyst is preferably one with high basicity, and specific examples include alkali salts such as sodium hydroxide (NaOH), potassium hydroxide (KOH), calcium hydroxide (Ca(OH) ₂ ), and 1,8-diazabicyclo[5.4.0]unde. Organic amines such as car-7-ene and 1,5-diazabicyclo[4.3.0]nona-5-ene, and ammonium hydroxides such as tetramethylammonium hydroxide and tetrabutylammonium hydroxide. You can. The above exemplary compounds can be used alone or in appropriate combinations. Among the above exemplary compounds, tetramethylammonium hydroxide is particularly preferable because it has high catalytic activity and is easy to obtain. In addition, when these basic catalysts are used as aqueous solutions, the hydrolysis reaction proceeds even in the condensation reaction process, so it is necessary to adjust the amount of water used during hydrolysis appropriately, such as reducing it in advance by the amount of water contained in the basic catalyst. There is.

The amount of basic catalyst added is preferably 0.01 to 5 parts by mass, more preferably 0.1 to 2 parts by mass, based on a total of 100 parts by mass of component (a1) and component (a2). If the amount of basic catalyst added is 5 parts by mass or less, the cured product produced using the obtained thiol group-containing silsesquioxane (condensate B) becomes difficult to color, and when the catalyst is removed, the removal process tends to become easy. There is. On the other hand, if it is 0.01 part by mass or more, the reaction can proceed appropriately, and the reaction time tends not to become excessively long.

The reaction temperature can be set arbitrarily depending on the reactivity of component (a1) or component (a2), but is usually about 40 to 150°C, preferably about 60 to 100°C. The condensation reaction is preferably carried out in the presence of a polar solvent, and does not contain a non-polar solvent such as toluene from the viewpoint of the stability of the resulting silsesquioxane compound A and its copolymer, an amic acid solution, and the quality of the resulting film. This is more preferable.

As a polar solvent, a polar solvent showing compatibility with water is preferable, and glycol ethers are particularly preferable. Moreover, among glycol ethers, dialkyl glycol ether-based solvents are particularly preferable. Examples of dialkyl glycol ether solvents that are compatible with water include ethylene glycol dimethyl ether, diethylene glycol dimethyl ether, triethylene glycol dimethyl ether, diethylene glycol methyl ethyl ether, and diethylene glycol diethyl ether. Additionally, glycol ether acetate-based solvents such as propylene glycol monomethyl ether acetate (PGMEA), dipropylene glycol monomethyl ether acetate, and propylene glycol monoethyl ether acetate can also be used.

Additionally, the condensation reaction can be performed by setting the reaction temperature and sequentially adding a solution containing the hydrolyzate obtained from the hydrolysis reaction to the polar solvent to which the dehydration condensation catalyst has been added. The addition method can be appropriately selected from various known methods. The time required for addition can be arbitrarily set depending on the reactivity of component (a1) or component (a2), but is usually about 30 minutes to 12 hours.

When carrying out the condensation reaction by the above method, it is preferable to carry out the reaction until the unreacted silanol groups are substantially eliminated. If unreacted silanol groups remain, the storage stability of the resulting thiol group-containing silsesquioxane (condensate B) or the composition containing condensate B is undesirable because the storage stability or heat resistance is reduced.

In addition, it is preferable to proceed so that the total molar ratio of unreacted alkoxy groups ([total number of moles of unreacted alkoxy groups]/[total number of moles of each alkoxy group contained in component (a1) or component (a2)]) is 0.2 or less. And it is more desirable to set it to substantially 0. When this molar ratio exceeds 0 and is 0.2 or less, some alkoxy groups remain in the resulting thiol group-containing silsesquioxane (condensate B), but this is preferable because adhesion to inorganic materials improves. By setting the molar ratio to 0, substantially no alkoxy groups remain, making it easy to produce a thick film cured product, and because the basket-like structure contained in the resulting thiol group-containing silsesquioxane (condensate B) is maximized, hardening This is particularly desirable because the heat resistance of water is improved. In addition, when it is not 0, the amount of random silsesquioxane contained in the obtained condensate B increases, and the molecular weight (Mw) of the condensate B tends to increase.

The condensation reaction is preferably carried out by solvent dilution so that the total concentration of component (a1) and component (a2) is about 2 to 80 mass%, and more preferably 15 to 75 mass%. It is preferable to use a solvent having a boiling point higher than that of the water and alcohol produced by the condensation reaction because these can be distilled off within the reaction system. When the concentration is 2% by mass or more, it is preferable because a sufficient amount of thiol group-containing silsesquioxane (condensate B) is contained in the resulting curable composition. If it is 80% by mass or less, it becomes difficult to gel during the reaction, and the molecular weight of the resulting condensate B tends to be appropriate.

It is preferable to remove the used catalyst after completion of the condensation reaction because the stability of the thiol group-containing silsesquioxane (condensate B) or the polyimide comprising the condensate B is improved. The removal method can be appropriately selected from various known methods depending on the catalyst used. For example, when tetramethylammonium hydroxide is used, after the condensation reaction is completed, it can be removed by methods such as adsorption and removal with a cation exchange resin.

<Fourth process>

The fourth step is a step of reacting the condensate B with dicarboxylic anhydride C having at least one type of reactive group selected from vinyl group, alkenyl group, cycloalkenyl group, alkynyl group, and acid chloride group.

As dicarboxylic acid anhydride C (hereinafter referred to as component (C)), a dicarboxylic acid anhydride having a functional group capable of reacting with a thiol group is used. For example, a dicarboxylic acid anhydride having a vinyl group, an acrylic group, a methacryl group, an allyl group, an alkenyl group, a cycloalkenyl group, an alkynyl group, or an acid chloride group can be used. More preferably, a dicarboxylic acid anhydride having a vinyl group, alkenyl group, cycloalkenyl group, alkynyl group, or acid chloride group can be used. In particular, the dicarboxylic acid anhydride C has the following structure.

Among these, the following compounds and compounds having an acid chloride group are particularly preferable because they have high reactivity. Additionally, when using dicarboxylic anhydride C with low reactivity, it is difficult to completely proceed with the reaction using UV light alone, so it is preferable to use an oxidation catalyst such as oxygen or iron chloride in combination.

In addition, among the dicarboxylic anhydrides C, phthalic anhydride compounds having an aromatic ring structure are preferable from the viewpoint of increasing the heat resistance of the resulting polyimide and suppressing yellowing under high temperature conditions, and having an alicyclic structure in the structure Maleic anhydride and cyclohexanedicarboxylic anhydride having , are preferred in that they can increase colorless transparency.

For the reaction between thiol group-containing silsesquioxane (condensate B) and dicarboxylic acid anhydride C, a thiol-ene reaction or a reaction between a thiol group and an acid chloride group can be used.

In the case of thiol-ene reaction, it is known that the reaction mechanism varies depending on the type of carbon-carbon double bond and the presence or absence of a radical polymerization initiator. That is, when a compound having a vinyl group or an allyl group with low radical polymerizability is used as component (C), only the en-thiol reaction proceeds, and the thiol group in the condensate B and the carbon-carbon double bond in component (C) It is preferable that the reaction occurs at an almost 1:1 (molar ratio). On the other hand, when a compound having a highly radically polymerizable acrylic or methacryl group is used as component (C), and especially when a radical polymerization initiator is used together, the polymerization reaction of the carbon-carbon double bond in component (C) also proceeds in parallel. Since the thiol group in the condensate B and the carbon-carbon double bond in component (C) react at about 1:1 to 100 (molar ratio), the effect of the invention may not be fully obtained. From the above viewpoint, when component (C) having a vinyl group or an allyl group with low radical polymerizability is used, the molar ratio ([number of moles of thiol group contained in condensate B]/[carbon contained in component (C)- It is preferable to mix so that the mole number of carbon double bonds] is 0.9 to 2.5, and more preferably 1.0. When this molar ratio is 0.9 or more, it is difficult for carbon-carbon double bonds to remain after ultraviolet curing, and weather resistance tends to improve. In addition, when it is 2.5 or less, the crosslinking density of the cured product becomes sufficient and heat resistance tends to be improved.

As an initiator for the thiol-ene reaction, an ultraviolet light source, organic material, inorganic material, or oxygen can be used. As an ultraviolet light source, for example, a high-pressure mercury lamp, a halogen lamp, a xenon lamp, or an ultraviolet LED can be used.

The initiator that can be used is not particularly limited, and conventionally known photocationic initiators, radical photoinitiators, oxidizing agents, etc. can be arbitrarily selected. Examples of photocationic initiators include sulfonium salts, iodonium salts, metallocene compounds, and benzointosylate, which are compounds that generate acid upon irradiation of ultraviolet rays. Commercially available products thereof include, for example, Cyracure UVI-6970. , UVI-6974, UVI-6990 (all brand names manufactured by Union Carbide, USA), Irgacure 264 (manufactured by BASF), and CIT-1682 (manufactured by Nippon Soda Co., Ltd.). The amount of the photocationic polymerization initiator used is usually about 10 parts by mass or less, preferably 1 to 5 parts by mass, per 100 parts by mass of the composition.

Examples of the photoradical initiator include Darocure 1173, Irgacure 651, Irgacure 184, Irgacure 907 (all brand names manufactured by BASF), benzophenone, etc., 5 parts by mass with respect to 100 parts by mass of the composition. or less, preferably 0.1 to 2 parts by mass. Additionally, the reaction can be promoted by adding an oxidizing agent such as iron oxide or iron chloride. However, in base film applications requiring high heat resistance and transparency, it is preferable to carry out the reaction using an ultraviolet light source or oxygen without using a photoreaction initiator or photosensitizer.

In the case of the reaction between the thiol group and the acid chloride group, it is preferable to add a dicarboxylic acid anhydride having an acid chloride group in an amount equivalent to or more than the sum of the thiol group amount and the silanol group amount of silsesquioxane (condensate B). If the amount of dicarboxylic acid anhydride having an acid chloride group added is small, the by-produced hydrochloric acid becomes a catalyst and condensation occurs between silanol groups, so gelation tends to occur, and as the amount of dicarboxylic acid anhydride added is large, the harmful effects are reduced. It becomes easy to reduce. Additionally, in that case, unreacted acid chloride groups may copolymerize with polyamic acid to produce polyamidoimide.

Additionally, in the case of a reaction between a thiol group and an acid chloride group, hydrochloric acid is generated as a by-product, so a base may be added as a pH adjuster. As the base, organic bases, tertiary amines and inorganic bases can be used. Examples of organic bases include N,N-dimethylacetamide, N,N-diethylacetamide, N,N-dimethylformamide, N,N-diethylformamide, N-methyl-2-pyrrolidone, Examples include 1,3-dimethyl-2-imidazolidinone, imidazole, N-methylcaprolactam, imidazole, N,N-dimethylaniline, and N,N-diethylaniline. Examples of tertiary amines include pyridine, collidine, lutidine, and triethylamine. Examples of inorganic bases include potassium hydroxide, sodium hydroxide, potassium carbonate, sodium carbonate, potassium bicarbonate, and sodium bicarbonate. However, in base film applications requiring high heat resistance and transparency, it is preferable to carry out the reaction using a volatile base. By removing hydrochloric acid by adding a base or heating the solution, gelation due to excessive reaction of silsesquioxane can be suppressed.

Solvents used in the reaction include the following. Benzene, toluene, xylene, mesitylene, pentane, hexane, heptane, octane, nonane, decane, N,N-dimethylacetamide, N,N-diethylacetamide, N,N-dimethylformamide, N,N- Diethylformamide, N-methyl-2-pyrrolidone, 1,3-dimethyl-2-imidazolidinone, imidazole, N-methylcaprolactam, dimethylsulfoxide, diethylsulfoxide, dimethylsulfone, dimethylsulfoxide Ethyl sulfone, hexamethyl sulfonamide, cresol, phenol, xylenol, diethylene glycol dimethyl ether (diglyme), triethylene glycol dimethyl ether (triglyme), tetraglyme, propylene glycol monomethyl ether acetate (PGMEA) , dioxane, tetrahydrofuran and γ-butyrolactone. You may use a mixture of at least two of these. In particular, considering productivity and optical properties of the film, it is preferable to use N,N-dimethylacetamide, N-methyl-2-pyrrolidone, or γ-butyrolactone as the main component of the organic solvent. In addition to these organic solvents, poor solvents such as toluene and xylene may be used to the extent that the polyimide resin or its precursor does not precipitate.

The silsesquioxane compound A having an acid anhydride group obtained in the fourth step can be used as is as a solution after the reaction, but it can also be used as a powder by filtering and separating foreign substances and gel-like substances, or by distilling off the solvent.

<Structure of silsesquioxane compound A having an acid anhydride group>

The silsesquioxane compound A obtained as described above preferably has structural units represented by the following general formulas (1) and (2), and has structural units represented by the general formulas (1) and (2). It is more desirable to have only one.

(Wherein, Q ¹ represents an aliphatic hydrocarbon group, an alicyclic hydrocarbon group, or an aromatic hydrocarbon group having 1 to 8 carbon atoms, and Q ² represents a single bond, a hydrocarbon group having 1 to 8 carbon atoms, or a carbon atom of a hydrocarbon group having 1 to 8 carbon atoms. at least one of which is an organic group or carbonyl group substituted with oxygen, and and one or more of the hydrogens bonded to them may be substituted with a hydrocarbon group, and 1.0≤m≤2.0 and 1.4≤n≤1.6.)

(In the formula, Q ³ represents an aliphatic hydrocarbon group, an alicyclic hydrocarbon group, or an aromatic hydrocarbon group having 1 to 8 carbon atoms, and 1.4≤n≤1.6.)

More specifically, Q ¹ in the general formula (1) represents a hydrocarbon group of 1 to 8 carbon atoms having a straight chain or branched chain or an aliphatic ring, or an aromatic hydrocarbon group of 6 to 8 carbon atoms that may have a hydrocarbon group. . As Q ¹ , a straight-chain hydrocarbon group is preferable from the viewpoint of providing flexibility to the polymer chain, and an alicyclic hydrocarbon group or aromatic hydrocarbon group is preferable from the viewpoint of improving heat resistance.

Specific examples of Q ¹ include a hydrocarbon group or an aromatic hydrocarbon group where the Si atom and the S atom of the compound exemplified as thiol group-containing trialkoxysilane a1 are bonded.

Q ² is a hydrocarbon group having 1 to 8 carbon atoms having a single bond, a straight chain, or a branched chain, an oxygen-containing hydrocarbon group in which at least one carbon atom is replaced with oxygen, or a carbonyl group. As Q ² , a straight-chain hydrocarbon group is preferable from the viewpoint of providing flexibility to the polymer chain, and a single bond, an alicyclic hydrocarbon group, or an aromatic hydrocarbon group is preferable from the viewpoint of improving heat resistance.

X is a carbon-carbon bond, or a complex of 4-10 fats, an aromatic epidemic of 6 to 10 carbon atoms, or a portion of the carbon constituting them with oxygen or sulfur, and binding to these hydrogen One or more may be substituted with a hydrocarbon group. As for In particular, when X is an aromatic hydrocarbon group, it is preferable from the viewpoint of increasing heat resistance and suppressing discoloration under high temperature conditions.

Specific examples of Q ² and Additionally, an example of a case where

Regarding m, it is 1.0≤m≤2.0, and m is preferably 1 from the viewpoint of small steric hindrance and increased reactivity of the dicarboxylic anhydride group. When m is 1.0<m<2.0 (i.e., other than an integer), as component (a1), one having one thiol group and one having two thiol groups are used in combination.

Regarding n, 1.4≤n≤1.6, and from the viewpoint of forming a more uniform three-dimensional structure, n is preferably 1.5. The assumption that n is other than 1.5 is intended to allow a small amount of not only trialkoxysilane but also dialkoxysilane and tetraalkoxysilane to be mixed in the raw materials.

In addition, Q ³ in the general formula (2) represents a hydrocarbon group of 1 to 8 carbon atoms having a straight chain or branched chain, or an aliphatic ring, or an aromatic hydrocarbon group of 6 to 8 carbon atoms, which may have a hydrocarbon group. As Q ³ , a short-chain or branched-chain hydrocarbon group or an aromatic hydrocarbon group is preferable from the viewpoint of suppressing crystallization and improving heat resistance. Specific examples of Q ³ include a hydrocarbon group or an aromatic hydrocarbon group bonded to the Si atom of a compound exemplified as trialkoxysilane a2.

In the silsesquioxane compound A having structural units represented by general formulas (1) and (2), the molar ratio of the structural units represented by general formula (2) ([structural unit (2)]/[structural unit ( 1) + structural unit (2)]) is preferably 0.1 or more and 0.7 or less, and more preferably 0.2 or more and 0.7 or less. As the molar ratio increases, the amount of thioether group or thioester group contained per molecule decreases, and as the value decreases, the amount of thioether group or thioester group increases. By falling within this range, the obtained polyimide chain is crosslinked appropriately, and the effect of improving physical properties is also sufficient.

The number of acid anhydride groups (number of functional groups) per molecule of silsesquioxane compound A is preferably 2 to 10, and more preferably 2.5 to 6. If the number of functional groups is within this range, the polyimide chain obtained is appropriately crosslinked, and the effect of improving physical properties is sufficient.

The molecular weight of silsesquioxane compound A is preferably 400 to 5000, and more preferably 600 to 3000. If the molecular weight is within this range, non-uniformity of the obtained polyimide is unlikely to occur and it is easy to obtain a uniform crosslinked structure.

General formulas (1) and (2) are easy to obtain randomly combined, but by combining them regularly, they can be formed into basket-shaped (including double decker-type), partially open basket-shaped, or ladder-shaped real sets. This can be done with a quinoxane compound.

As a method of obtaining silsesquioxane compound A of this structure, in the condensate B (thiol group-containing silsesquioxane compound) step, a silsesquioxane compound in the form of a basket or a partially open basket or ladder is obtained. A method of placing it or a method of using a commercially available thiol group-containing silsesquioxane compound having this structure is included.

Condensate B can be synthesized by dehydration condensation of dialkylsilanediol or dehydrochlorination reaction of dialkylsilanediol and dialkyldichlorosilane. By adjusting the catalyst, solvent, or substrate concentration used, the production rate of a specific structure can be increased. A specific structure can be isolated by purifying the obtained product by methods such as recrystallization, solvent washing, and column separation. The method is not particularly limited, but for example, review articles ((1) “Silicon’s expanding application fields and technology trends”, by Yoshiaki Ono, Chemical Industry Daily, (2) “Science of Silicon”, Nobuo Matsumoto (松本)信雄), Electronic Information and Communications Society, (3) 「Latest application technology of silicon」, Makoto Kumada, supervised by Tadashi Wada, CMC Shutpan, (4) 「Selection and optimality of silicon compounds Utilization Technology", Technical Information Association edition, (5) "Organosilicon Science in the 21st Century", supervised by Kohei Tamao, CMC Shotpan, (6) "Development of Chemistry and Application of Silsesquioxane Materials", Ito The method described in Maki Supervision, CMC Shotpan, etc. can be adopted. T ^H ₈ , a type of basket-like structure, can be synthesized, for example, by hydrolysis of trichlorosilane in the presence of iron chloride (Bull. Chem. Soc. Jpn., 73, 215 (2000)). Various derivatives can be synthesized by further chemically modifying T ^H ₈ to the starting material. For example, in the case of introducing an organic group by hydrosilylation of T ^H ₈ , an organic group is introduced by reacting an alkenyl compound in the presence of a platinum catalyst. When T ^H ₈ is reacted with chlorine, T ^Cl ₈ is obtained, and when methyl orthoformate is further reacted, a methoxy group can be introduced. T ^Ph ₄ T ^Ph ₃ (ONa) ₃ , which has a double decker structure, is produced almost quantitatively when trimethoxy(phenyl)silane is hydrolyzed in the presence of sodium hydroxide. A method of synthesizing condensate B having a ladder-like structure is a method of hydrolyzing trichloro(phenyl)silane followed by an alkali equilibration reaction using potassium hydroxide as a catalyst (Chem. Rev., 95, 1409 (1995) )), or a method of synthesis by hydrolytic polycondensation of trichloro(phenyl)silane using a correlation transfer catalyst (Journal of the Silicon Chemical Society, (8), 16 (1997)).

<Polyamic acid>

The polyamic acid of the present invention is, at least as described above, a copolymerization product of a silsesquioxane derivative (i.e., a silsesquioxane compound), carboxylic acids, and diamines.

In particular, when a silsesquioxane compound having an acid anhydride group exceeding 2 is used as the silsesquioxane compound, a crosslinked structure can be formed in the polyimide as a copolymerization component.

Regarding polyimide, there is generally a trade-off relationship between practical properties such as heat resistance and mechanical properties and colorlessness (transparency to whiteness), and in particular, a method of producing a polyimide film with improved toughness while maintaining other main properties The emergence of was being demanded.

By using a polyamic acid containing a silsesquioxane compound as a copolymerization component, a polyimide film with improved toughness can be produced while maintaining other main properties, and therefore, the polyamic acid of the present invention is particularly useful as a raw material thereof. . A polyimide film can be obtained, for example, by including a step of synthesizing polyamic acid in a solution, a step of forming a polyamic acid solution into a film, and a step of imidizing the polyamic acid.

<Synthesis of polyamic acid>

For the synthesis of polyamic acid, for example, at least carboxylic acids, diamines, and silsesquioxane compounds can be reacted in a solvent. That is, at least carboxylic acids and diamines can be used as monomer components other than the silsesquioxane compound.

There are no particular restrictions on the carboxylic acids, and include alicyclic tetracarboxylic anhydride, aromatic tetracarboxylic anhydride, tricarboxylic acid, and dicarboxylic acid commonly used in polyimide synthesis, polyamidoimide synthesis, and polyamide synthesis. etc. can be used. From the viewpoint of heat resistance, aromatics are preferable, and from the viewpoint of transparency, alicyclics are preferable. These may be used individually, or two or more types may be used together.

Examples of the alicyclic tetracarboxylic acid anhydride in the present invention include 1,2,3,4-cyclobutanetetracarboxylic acid, 1,2,3,4-cyclopentanetetracarboxylic acid, and 1,2,3,4. -Cyclohexanetetracarboxylic acid, 1,2,4,5-cyclohexanetetracarboxylic acid, 3,3',4,4'-bicyclohexyltetracarboxylic acid, bicyclo[2,2,1] Heptane-2,3,5,6-tetracarboxylic acid, bicyclo[2,2,2]octane-2,3,5,6-tetracarboxylic acid, bicyclo[2,2,2]oct- 7-N-2,3,5,6-tetracarboxylic acid, tetrahydroanthracene-2,3,6,7-tetracarboxylic acid, tetradecahydro-1,4:5,8:9,10- Trimethanoanthracene-2,3,6,7-tetracarboxylic acid, decahydronaphthalene-2,3,6,7-tetracarboxylic acid, decahydro-1,4:5,8-dimethanonaphthalene -2,3,6,7-tetracarboxylic acid, decahydro-1,4-ethano-5,8-methanonaphthalene-2,3,6,7-tetracarboxylic acid, norbornane-2 -Spiro-α-cyclopentanone-α'-spiro-2''-norbornane-5,5'',6,6''-tetracarboxylic acid (aka "norbornane-2-spiro-2 '-cyclopentanone-5'-spiro-2''-norbornane-5,5'',6,6''-tetracarboxylic acid"), methylnorbornane-2-spiro-α-cyclo Pentanone-α'-spiro-2''-(methylnorbornane)-5,5'',6,6''-tetracarboxylic acid, norbornane-2-spiro-α-cyclohexanone- α'-spiro-2''-norbornane-5,5'',6,6''-tetracarboxylic acid (aka "norbornane-2-spiro-2'-cyclohexanone-6'- Spiro-2''-norbornane-5,5'',6,6''-tetracarboxylic acid"), methylnorbornane-2-spiro-α-cyclohexanone-α'-spiro-2 ''-(methylnorbornane)-5,5'',6,6''-tetracarboxylic acid, norbornane-2-spiro-α-cyclopropanone-α'-spiro-2''- norbornane-5,5'',6,6''-tetracarboxylic acid, norbornane-2-spiro-α-cyclobutanone-α'-spiro-2''-norbornane-5, 5'',6,6''-tetracarboxylic acid, norbornane-2-spiro-α-cycloheptanone-α'-spiro-2''-norbornane-5,5'',6, 6''-Tetracarboxylic acid, norbornane-2-spiro-α-cyclooctanone-α'-spiro-2''-norbornane-5,5'',6,6''-tetracar Boxylic acid, norbornane-2-spiro-α-cyclononanone-α'-spiro-2''-norbornane-5,5'',6,6''-tetracarboxylic acid, norbornane -2-spiro-α-cyclodecanone-α'-spiro-2''-norbornane-5,5'',6,6''-tetracarboxylic acid, norbornane-2-spiro-α -Cycloundecanone-α'-spiro-2''-norbornane-5,5'',6,6''-tetracarboxylic acid, norbornane-2-spiro-α-cyclododecanone-α '-spiro-2''-norbornane-5,5'',6,6''-tetracarboxylic acid, norbornane-2-spiro-α-cyclotridecanone-α'-spiro-2 ''-norbornane-5,5'',6,6''-tetracarboxylic acid, norbornane-2-spiro-α-cyclotetradecanone-α'-spiro-2''-norborne I-5,5'',6,6''-tetracarboxylic acid, norbornane-2-spiro-α-cyclopentadecanone-α'-spiro-2''-norbornane-5,5 '',6,6''-tetracarboxylic acid, norbornane-2-spiro-α-(methylcyclopentanone)-α'-spiro-2''-norbornane-5,5'', 6,6''-Tetracarboxylic acid, norbornane-2-spiro-α-(methylcyclohexanone)-α'-spiro-2''-norbornane-5,5'',6,6 Tetracarboxylic acids such as ''-tetracarboxylic acid and their acid anhydrides can be mentioned. Among these, dianhydrides having two acid anhydride structures are suitable, especially 1,2,3,4-cyclobutanetetracarboxylic dianhydride, 1,2,3,4-cyclohexanetetracarboxylic dianhydride, 1,2,4,5-cyclohexanetetracarboxylic dianhydride is preferred, 1,2,3,4-cyclobutanetetracarboxylic dianhydride, 1,2,4,5-cyclohexanetetracarboxyl Acid dianhydride is more preferable, and 1,2,3,4-cyclobutanetetracarboxylic dianhydride is still more preferable. In addition, these may be used individually, or two or more types may be used together.

Examples of the aromatic tetracarboxylic anhydride in the present invention include 4,4'-(2,2-hexafluoroisopropylidene)diphthalic acid, 4,4'-oxydiphthalic acid, and bis(1,3-dioxo-). 1,3-dihydro-2-benzofuran-5-carboxylic acid) 1,4-phenylene, bis (1,3-dioxo-1,3-dihydro-2-benzofuran-5-yl) Benzene-1,4-dicarboxylate, 4,4'-[4,4'-(3-oxo-1,3-dihydro-2-benzofuran-1,1-diyl)bis(benzene-1 ,4-diyloxy)]dibenzene-1,2-dicarboxylic acid, 3,3',4,4'-benzophenonetetracarboxylic acid, 4,4'-[(3-oxo-1, 3-dihydro-2-benzofuran-1,1-diyl)bis(toluene-2,5-diyloxy)]dibenzene-1,2-dicarboxylic acid, 4,4'-[(3- oxo-1,3-dihydro-2-benzofuran-1,1-diyl)bis(1,4-xylene-2,5-diyloxy)]dibenzene-1,2-dicarboxylic acid, 4 ,4'-[4,4'-(3-oxo-1,3-dihydro-2-benzofuran-1,1-diyl)bis(4-isopropyl-toluene-2,5-diyloxy) ]Dibenzene-1,2-dicarboxylic acid, 4,4'-[4,4'-(3-oxo-1,3-dihydro-2-benzofuran-1,1-diyl)bis(naphthalene) -1,4-diyloxy)]dibenzene-1,2-dicarboxylic acid, 4,4'-[4,4'-(3H-2,1-benzoxathiol-1,1-dioxide- 3,3-diyl)bis(benzene-1,4-diyloxy)]dibenzene-1,2-dicarboxylic acid, 4,4'-benzophenonetetracarboxylic acid, 4,4'-[( 3H-2,1-benzoxathiol-1,1-dioxide-3,3-diyl)bis(toluene-2,5-diyloxy)]dibenzene-1,2-dicarboxylic acid, 4,4 '-[(3H-2,1-benzoxathiol-1,1-dioxide-3,3-diyl)bis(1,4-xylene-2,5-diyloxy)]dibenzene-1,2- Dicarboxylic acid, 4,4'-[4,4'-(3H-2,1-benzoxathiol-1,1-dioxide-3,3-diyl)bis(4-isopropyl-toluene-2, 5-diyloxy)]dibenzene-1,2-dicarboxylic acid, 4,4'-[4,4'-(3H-2,1-benzoxathiol-1,1-dioxide-3,3 -diyl)bis(naphthalene-1,4-diyloxy)]dibenzene-1,2-dicarboxylic acid, 3,3',4,4'-benzophenonetetracarboxylic acid, 3,3', 4,4'-benzophenonetetracarboxylic acid, 3,3',4,4'-diphenylsulfonetetracarboxylic acid, 3,3',4,4'-biphenyltetracarboxylic acid, 2,3 ,3',4'-biphenyltetracarboxylic acid, pyromellitic acid, 4,4'-[spiro(xanthene-9,9'-fluorene)-2,6-diylbis(oxycarbonyl)] Tetracarboxylic acids such as diphthalic acid, 4,4'-[spiro(xanthene-9,9'-fluorene)-3,6-diylbis(oxycarbonyl)]diphthalic acid, and their acid anhydrides. You can. In addition, aromatic tetracarboxylic acids may be used individually or two or more types may be used in combination.

Tricarboxylic acids include trimellitic acid, 1,2,5-naphthalene tricarboxylic acid, diphenyl ether-3,3',4'-tricarboxylic acid, and diphenyl sulfone-3,3',4'. -Aromatic tricarboxylic acids such as tricarboxylic acid, or hydrogenated products of these aromatic tricarboxylic acids such as hexahydrotrimellitic acid, ethylene glycol bistrimellitate, propylene glycol bistrimellitate, and 1,4-butanediol. Alkylene glycol bistri mellitate, such as bistri mellitate and polyethylene glycol bistri mellitate, and monoanhydrides and esters thereof. Among these, monoanhydrides having one acid anhydride structure are suitable, and trimellitic acid anhydride and hexahydrotrimellitic acid anhydride are particularly preferable. In addition, these may be used individually or in combination of plurality.

As dicarboxylic acids, aromatic dicarboxylic acids such as terephthalic acid, isophthalic acid, orthophthalic acid, naphthalenedicarboxylic acid, 4,4'-oxydibenzenecarboxylic acid, or 1,6-cyclohexanedicarboxylic acid. Hydrogenated products of the above aromatic dicarboxylic acids, such as oxalic acid, succinic acid, glutaric acid, adipic acid, heptanoic acid, octanoic acid, azelaic acid, sebacic acid, undecanoic acid, dodecanoic acid, 2- Examples include methylsuccinic acid and acid chlorides or esters thereof. Among these, aromatic dicarboxylic acids and their hydrogenated products are suitable, and terephthalic acid, 1,6-cyclohexanedicarboxylic acid, and 4,4'-oxydibenzenecarboxylic acid are particularly preferable. In addition, dicarboxylic acids may be used individually or in combination of multiple dicarboxylic acids.

As carboxylic acids, it is particularly preferable that they are one or more compounds represented by the chemical formulas selected below.

That is, it is preferable that the polyamic acid has a structural unit derived from one or more of these compounds. Additionally, the polyamic acid does not need to have a structural unit derived from 3,3',4,4'-biphenyltetracarboxylic dianhydride, that is, BPDA.

The diamines in the present invention are not particularly limited, and aromatic diamines, aliphatic diamines, and alicyclic diamines commonly used in polyimide synthesis, polyamidoimide synthesis, and polyamide synthesis can be used. Aromatic diamines are preferable from the viewpoint of heat resistance, and alicyclic diamines are preferable from the viewpoint of transparency. Diamines may be used individually or two or more types may be used in combination.

As aromatic diamines, for example, 2,2'-dimethyl-4,4'-diaminobiphenyl, 1,4-bis[2-(4-aminophenyl)-2-propyl]benzene, 1,4-bis( 4-amino-2-trifluoromethylphenoxy)benzene, 2,2'-ditrifluoromethyl-4,4'-diaminobiphenyl, 4,4'-bis(4-aminophenoxy)bi Phenyl, 4,4'-bis(3-aminophenoxy)biphenyl, bis[4-(3-aminophenoxy)phenyl]ketone, bis[4-(3-aminophenoxy)phenyl]sulfide, bis [4-(3-aminophenoxy)phenyl]sulfone, 2,2-bis[4-(3-aminophenoxy)phenyl]propane, 2,2-bis[4-(3-aminophenoxy)phenyl] -1,1,1,3,3,3-hexafluoropropane, m-phenylenediamine, o-phenylenediamine, p-phenylenediamine, m-aminobenzylamine, p-aminobenzylamine, 4- Amino-N-(4-aminophenyl)benzamide, 3,3'-diaminodiphenyl ether, 3,4'-diaminodiphenyl ether, 4,4'-diaminodiphenyl ether, 2,2' -Trifluoromethyl-4,4'-diaminodiphenyl ether, 3,3'-diaminodiphenyl sulfide, 3,4'-diaminodiphenyl sulfide, 4,4'-diaminodiphenyl Sulfide, 3,3'-diaminodiphenyl sulfoxide, 3,4'-diaminodiphenyl sulfoxide, 4,4'-diaminodiphenyl sulfoxide, 3,3'-diaminodiphenyl sulfone, 3,4'-diaminodiphenylsulfone, 4,4'-diaminodiphenylsulfone, 3,3'-diaminobenzophenone, 3,4'-diaminobenzophenone, 4,4'-diaminobenzo Phenone, 3,3'-diaminodiphenylmethane, 3,4'-diaminodiphenylmethane, 4,4'-diaminodiphenylmethane, bis[4-(4-aminophenoxy)phenyl]methane, 1,1-bis[4-(4-aminophenoxy)phenyl]ethane, 1,2-bis[4-(4-aminophenoxy)phenyl]ethane, 1,1-bis[4-(4-amino) Phenoxy)phenyl]propane, 1,2-bis[4-(4-aminophenoxy)phenyl]propane, 1,3-bis[4-(4-aminophenoxy)phenyl]propane, 2,2-bis [4-(4-aminophenoxy)phenyl]propane, 1,1-bis[4-(4-aminophenoxy)phenyl]butane, 1,3-bis[4-(4-aminophenoxy)phenyl] Butane, 1,4-bis[4-(4-aminophenoxy)phenyl]butane, 2,2-bis[4-(4-aminophenoxy)phenyl]butane, 2,3-bis[4-(4 -Aminophenoxy)phenyl]butane, 2-[4-(4-aminophenoxy)phenyl]-2-[4-(4-aminophenoxy)-3-methylphenyl]propane, 2,2-bis[4 -(4-aminophenoxy)-3-methylphenyl]propane, 2-[4-(4-aminophenoxy)phenyl]-2-[4-(4-aminophenoxy)-3,5-dimethylphenyl] Propane, 2,2-bis[4-(4-aminophenoxy)-3,5-dimethylphenyl]propane, 2,2-bis[4-(4-aminophenoxy)phenyl]-1,1,1 ,3,3,3-hexafluoropropane, 1,4-bis(3-aminophenoxy)benzene, 1,3-bis(3-aminophenoxy)benzene, 1,4-bis(4-aminophenoxy) si) benzene, 4,4'-bis(4-aminophenoxy)biphenyl, bis[4-(4-aminophenoxy)phenyl]ketone, bis[4-(4-aminophenoxy)phenyl]sulfide , bis[4-(4-aminophenoxy)phenyl]sulfoxide, bis[4-(4-aminophenoxy)phenyl]sulfone, bis[4-(3-aminophenoxy)phenyl]ether, bis[4 -(4-aminophenoxy)phenyl]ether, 1,3-bis[4-(4-aminophenoxy)benzoyl]benzene, 1,3-bis[4-(3-aminophenoxy)benzoyl]benzene, 1,4-bis[4-(3-aminophenoxy)benzoyl]benzene, 4,4'-bis[(3-aminophenoxy)benzoyl]benzene, 1,1-bis[4-(3-aminophenok) Si) phenyl] propane, 1,3-bis [4- (3-aminophenoxy) phenyl] propane, 3,4'-diaminodiphenyl sulfide, 2,2-bis [3- (3-aminophenok) C)phenyl]-1,1,1,3,3,3-hexafluoropropane, bis[4-(3-aminophenoxy)phenyl]methane, 1,1-bis[4-(3-aminophenok) Si) phenyl] ethane, 1,2-bis [4- (3-aminophenoxy) phenyl] ethane, bis [4- (3-aminophenoxy) phenyl] sulfoxide, 4,4'-bis [3- (4-aminophenoxy)benzoyl]diphenyl ether, 4,4'-bis[3-(3-aminophenoxy)benzoyl]diphenyl ether, 4,4'-bis[4-(4-amino-α ,α-dimethylbenzyl)phenoxy]benzophenone, 4,4'-bis[4-(4-amino-α,α-dimethylbenzyl)phenoxy]diphenylsulfone, bis[4-{4-(4- Aminophenoxy)phenoxy}phenyl]sulfone, 1,4-bis[4-(4-aminophenoxy)phenoxy-α,α-dimethylbenzyl]benzene, 1,3-bis[4-(4-amino) Phenoxy) phenoxy-α,α-dimethylbenzyl]benzene, 1,3-bis[4-(4-amino-6-trifluoromethylphenoxy)-α,α-dimethylbenzyl]benzene, 1,3 -bis[4-(4-amino-6-fluorophenoxy)-α,α-dimethylbenzyl]benzene, 1,3-bis[4-(4-amino-6-methylphenoxy)-α,α -dimethylbenzyl]benzene, 1,3-bis[4-(4-amino-6-cyanophenoxy)-α,α-dimethylbenzyl]benzene, 3,3'-diamino-4,4'-dipe Noxybenzophenone, 4,4'-diamino-5,5'-diphenoxybenzophenone, 3,4'-diamino-4,5'-diphenoxybenzophenone, 3,3'-diamino -4-phenoxybenzophenone, 4,4'-diamino-5-phenoxybenzophenone, 3,4'-diamino-4-phenoxybenzophenone, 3,4'-diamino-5'-phenoc Cybenzophenone, 3,3'-diamino-4,4'-divinoxybenzophenone, 4,4'-diamino-5,5'-diviphenoxybenzophenone, 3,4'-diamino- 4,5'-Dibiphenoxybenzophenone, 3,3'-Diamino-4-biphenoxybenzophenone, 4,4'-Diamino-5-biphenoxybenzophenone, 3,4'-Diamino -4-biphenoxybenzophenone, 3,4'-diamino-5'-biphenoxybenzophenone, 1,3-bis(3-amino-4-phenoxybenzoyl)benzene, 1,4-bis( 3-amino-4-phenoxybenzoyl)benzene, 1,3-bis(4-amino-5-phenoxybenzoyl)benzene, 1,4-bis(4-amino-5-phenoxybenzoyl)benzene, 1, 3-bis(3-amino-4-biphenoxybenzoyl)benzene, 1,4-bis(3-amino-4-biphenoxybenzoyl)benzene, 1,3-bis(4-amino-5-biphenok) Cibenzoyl)benzene, 1,4-bis(4-amino-5-biphenoxybenzoyl)benzene, 2,6-bis[4-(4-amino-α,α-dimethylbenzyl)phenoxy]benzonitrile, 4,4'-[9H-fluorene-9,9-diyl]bisaniline (aka "9,9-bis(4-aminophenyl)fluorene"), spiro(xanthene-9,9'-fluorene )-2,6-diylbis(oxycarbonyl)]bisaniline, 4,4'-[spiro(xanthene-9,9'-fluorene)-2,6-diylbis(oxycarbonyl)]bis Aniline, 4,4'-[spiro(xanthene-9,9'-fluorene)-3,6-diylbis(oxycarbonyl)]bisaniline, 5-amino-2-(p-aminophenyl)benzo Oxazole, 6-amino-2-(p-aminophenyl)benzoxazole, 5-amino-2-(m-aminophenyl)benzoxazole, 6-amino-2-(m-aminophenyl)benzoxazole , 2,2'-p-phenylenebis(5-aminobenzoxazole), 2,2'-p-phenylenebis(6-aminobenzooxazole), 1-(5-aminobenzooxazolo)- 4-(6-Aminobenzoxazolo)benzene, 2,6-(4,4'-diaminodiphenyl)benzo[1,2-d:5,4-d']bisoxazole, 2,6- (4,4'-diaminodiphenyl)benzo[1,2-d:4,5-d']bisoxazole, 2,6-(3,4'-diaminodiphenyl)benzo[1,2 -d:5,4-d']bisoxazole, 2,6-(3,4'-diaminodiphenyl)benzo[1,2-d:4,5-d']bisoxazole, 2, 6-(3,3'-diaminodiphenyl)benzo[1,2-d:5,4-d']bisoxazole, 2,6-(3,3'-diaminodiphenyl)benzo[1 ,2-d:4,5-d']bisoxazole, etc. are mentioned. In addition, part or all of the hydrogen atoms on the aromatic ring of the aromatic diamine may be substituted with a halogen atom, an alkyl group or alkoxyl group having 1 to 3 carbon atoms, or a cyano group, and the hydrogen of the alkyl group or alkoxyl group having 1 to 3 carbon atoms may be substituted. Some or all of the atoms may be replaced with halogen atoms.

Examples of alicyclic diamines include 1,4-diaminocyclohexane, 1,4-diamino-2-methylcyclohexane, 1,4-diamino-2-ethylcyclohexane, and 1,4-diamino-2. -n-propylcyclohexane, 1,4-diamino-2-isopropylcyclohexane, 1,4-diamino-2-n-butylcyclohexane, 1,4-diamino-2-isobutylcyclohexane, 1,4-diamino-2-sec-butylcyclohexane, 1,4-diamino-2-tert-butylcyclohexane, 4,4'-methylenebis(2,6-dimethylcyclohexylamine), 9, 10-bis(4-aminophenyl)adenine, 2,4-bis(4-aminophenyl)cyclobutane-1,3-dicarboxylic acid dimethyl, etc.

As diamines, it is particularly preferable to include 4,4'-diamino-2,2'-bis(trifluoromethyl)biphenyl (TFMB) or 4,4'-diaminobenzanilide (DABA), 4 ,4'-diamino-2,2'-bis(trifluoromethyl)biphenyl (TFMB) or 4,4'-diaminobenzanilide (DABA) is more preferable.

When the silsesquioxane compound, that is, the silsesquioxane derivative, has two or more acid anhydride groups, the number of moles of structural units derived from the silsesquioxane derivative (provided, that the acid anhydride group having more than two silsesquioxane derivatives When having a group, this number of moles is the total number of moles of the silsesquioxane derivative divided by the total number of acid anhydride groups of the silsesquioxane derivative and doubled) is the number of moles of the structural unit derived from the silsesquioxane derivative and the number of moles of the structural unit derived from the silsesquioxane derivative It is 0.0001 times or more than the total number of moles of structural units derived from boxylic acids. Here, “the total number of acid anhydride groups of the silsesquioxane derivative” means the number of acid anhydride groups per molecule of the silsesquioxane derivative.

That is, the molar content of the structural unit derived from the silsesquioxane derivative (specifically, the molar content based on the divalent monomer, that is, the molar content in divalent conversion) is 0.0001 mol% or more. The molar content rate is a value obtained by the following calculation.

(nA/(nA+nD))×100

(Here, nA is the total number of moles of structural units derived from silsesquioxane derivatives divided by the total number of acid anhydride groups and doubled, and nD is the number of moles of structural units derived from carboxylic acids.)

In addition, here too, the “total number of acid anhydride groups” means the number of acid anhydride groups per molecule of silsesquioxane derivative.

When the mole number of the structural unit derived from the silsesquioxane derivative is 0.0001 times or more, the toughness of the polyimide film can be effectively improved. The number of moles of the structural unit derived from the silsesquioxane derivative is preferably 0.001 times or more, more preferably 0.005 times or more, and still more preferably 0.01 times or more.

On the other hand, the number of moles of structural units derived from the silsesquioxane derivative is 0.09 times or less. That is, the molar content of the structural unit derived from the silsesquioxane derivative is 0.09 mol% or less. By being 0.09 times or less, the degree of increase in CTE derived from silsesquioxane derivatives can be suppressed. In other words, CTE can be maintained. In other words, a significant increase in CTE can be suppressed. Additionally, the thermal decomposition temperature and glass transition temperature can be maintained. In other words, a significant decrease in thermal decomposition temperature or glass transition temperature can be suppressed. Moreover, the toughness of the polyimide film can be effectively improved. In addition, when the silsesquioxane derivative has a SiOH group (e.g., a residual SiOH group), gelation of the polyamic acid solution tends to occur (this tendency is particularly prevalent in the silsesquioxane derivative with a random structure). (strongly in ), by setting the molar number of structural units derived from the silsesquioxane derivative to 0.09 times or less, gelation of the polyamic acid solution can be suppressed or reduced. In other words, the temporal stability of the polyamic acid solution can be improved. The number of moles of structural units derived from the silsesquioxane derivative is preferably 0.08 times or less. The number of moles of structural units derived from the silsesquioxane derivative may be 0.07 times or less, and may be 0.06 times or less.

When a silsesquioxane compound, that is, a silsesquioxane derivative, has two or more amino groups, the number of moles of structural units derived from the silsesquioxane derivative (provided, that the silsesquioxane derivative has more than two amino groups) In this case, this number of moles is the total number of moles of the silsesquioxane derivative divided by the total number of amino groups of the silsesquioxane derivative and doubled) is the number of moles of structural units derived from the silsesquioxane derivative and the number of moles derived from diamines It is 0.0001 times more than the total number of moles of structural units. Here, “total number of amino groups of silsesquioxane derivative” means the number of amino groups per molecule of silsesquioxane derivative.

That is, the molar content of the structural unit derived from the silsesquioxane derivative (specifically, the molar content based on the divalent monomer, that is, the molar content in divalent conversion) is 0.0001 mol% or more. The molar content rate is a value obtained by the following calculation.

(nA/(nA+nD))×100

(Here, nA is the total number of moles of structural units derived from silsesquioxane derivatives divided by the total number of amino groups and doubled, and nD is the number of moles of structural units derived from diamines.)

Also, here, the “total number of amino groups” means the number of amino groups per molecule of silsesquioxane derivative.

When the mole number of the structural unit derived from the silsesquioxane derivative is 0.0001 times or more, the toughness of the polyimide film can be effectively improved. The number of moles of the structural unit derived from the silsesquioxane derivative is preferably 0.001 times or more, more preferably 0.005 times or more, and still more preferably 0.01 times or more.

On the other hand, the number of moles of structural units derived from the silsesquioxane derivative is 0.09 times or less. That is, the molar content of the structural unit derived from the silsesquioxane derivative is 0.09 mol% or less. By being 0.09 times or less, the degree of increase in CTE derived from silsesquioxane derivatives can be suppressed. In other words, CTE can be maintained. In other words, a significant increase in CTE can be suppressed. Additionally, the thermal decomposition temperature and glass transition temperature can be maintained. In other words, a significant decrease in thermal decomposition temperature or glass transition temperature can be suppressed. Moreover, the toughness of the polyimide film can be effectively improved. In addition, when the silsesquioxane derivative has a SiOH group (e.g., a residual SiOH group), gelation of the polyamic acid solution tends to occur (this tendency is particularly prevalent in the silsesquioxane derivative with a random structure). (strongly in ), by setting the molar number of structural units derived from the silsesquioxane derivative to 0.09 times or less, gelation of the polyamic acid solution can be suppressed or reduced. In other words, the temporal stability of the polyamic acid solution can be improved. The number of moles of structural units derived from the silsesquioxane derivative is preferably 0.08 times or less. The number of moles of structural units derived from the silsesquioxane derivative may be 0.07 times or less, and may be 0.06 times or less.

The solvent used in the synthesis of polyamic acid can be any solvent that dissolves polyamic acid and its monomers, and examples include aprotic solvents, phenol-based solvents, ether and glycol-based solvents.

Specifically, aprotic solvents include N,N-dimethylformamide, N,N-dimethylacetamide, N-methyl-2-pyrrolidone, N-methylcaprolactam, 1,3-dimethylimidazolidinone, Amide-based solvents such as tetramethylurea; Lactone-based solvents such as γ-butyrolactone and γ-valerolactone; Phosphorus-containing amide-based solvents such as hexamethylphosphoricamide and hexamethylphosphinetriamide; Sulfur-containing solvents such as dimethyl sulfone, dimethyl sulfoxide, and sulfolane; Ketone-based solvents such as cyclohexanone and methylcyclohexanone; Tertiary amine-based solvents such as picoline and pyridine; and ester-based solvents such as acetic acid (2-methoxy-1-methylethyl).

Examples of phenol-based solvents include phenol, o-cresol, m-cresol, p-cresol, 2,3-xylenol, 2,4-xylenol, 2,5-xylenol, and 2,6-xylenol. , 3,4-xylenol, 3,5-xylenol, etc. Examples of ether and glycol-based solvents include 1,2-dimethoxyethane, bis(2-methoxyethyl)ether, 1,2-bis(2-methoxyethoxy)ethane, and bis[2-(2-methoxyethyl). Toxy)ethyl]ether, tetrahydrofuran, 1,4-dioxane, etc. are mentioned.

Among them, from the viewpoint of solubility and film formation, it is preferable that the solvent contains N-methyl-2-pyrrolidone, N,N'-dimethylacetamide, or γ-butyrolactone as a main component. The above-described solvents may be used individually or in combination of two or more types.

As conditions during synthesis, the reaction temperature is preferably -30 to 200°C, more preferably 20 to 180°C, and especially preferably 20 to 100°C. Stirring can be continued at room temperature (20-25°C) or an appropriate reaction temperature, and the end point of the reaction can be set when the viscosity of the polyimide precursor becomes constant. The reaction can usually be completed in 3 to 100 hours.

<Polyamic acid composition>

The polyamic acid composition of the present invention contains the polyamic acid and solvent as described above. It is possible for the polyamic acid composition to contain a solvent different from the solvent used during synthesis, but from the viewpoint of avoiding a complicated manufacturing process, it is preferable to contain the solvent used during synthesis. Therefore, it is preferable that the main component of the solvent contained in the polyamic acid composition is N-methyl-2-pyrrolidone, N,N'-dimethylacetamide, or γ-butyrolactone.

The content of polyamic acid is preferably 5 to 30% by mass, and more preferably 10 to 20% by mass, in the polyamic acid composition from the viewpoint of film thickness at the time of film formation. If the content is within this range, a thin film with excellent handleability can be obtained.

The polyamic acid composition may further contain optional ingredients such as an adhesion agent, a surfactant, a leveling agent, an antioxidant, a UV absorber, a chemical imidizing agent, a colorant, and a bluing agent. Additionally, fillers that can be included in the polyimide film may be further included.

<Polyimide>

The polyimide of the present invention is obtained by imidizing the polyamic acid described above. Polyimide can be obtained, for example, by heating the polyamic acid. By heating, the carboxyl groups of the polyamic acid are each dehydrated and ring-closed, and the polyamic acid is imidized to form a polyimide structure.

Polyimide can be obtained by heating polyamic acid in a solvent. The heating temperature for imidizing the polyamic acid in the solvent is preferably 150 to 220°C.

In addition, polyimide can be provided as a film-shaped or film-shaped molded body by applying a polyamic acid composition containing a solvent to a substrate and heating it, as described later. The heating temperature when imidizing polyamic acid is preferably 250 to 400°C when the solvent is dry to a certain extent. Coloration due to oxidation of terminal amino groups can be suppressed by adding a terminal amino group sealant to a polyamic acid composition containing a solvent and heat treating it. The terminal amino group sealant is not particularly limited as long as it is a compound that reacts with an amino group to form a chemical bond, but for example, acetic anhydride can be used.

Additionally, polyimide can also be obtained by chemical imidization instead of thermal imidization. In that case, it is preferable to use a tertiary amine as the imidization accelerator. As the tertiary amine, heterocyclic tertiary amine is more preferable. Preferred specific examples of heterocyclic tertiary amines include pyridine, 2,5-diethylpyridine, picoline, quinoline, and isoquinoline.

<Polyimide film>

The polyimide film of the present invention contains the polyimide described above. When the polyimide film is composed of two or more layers, at least one layer may contain the polyimide of the present invention.

A polyimide film can be obtained, for example, by casting a polyamic acid solution on a substrate, heating it to volatilize the solvent to form a uniform green film with a thickness of 1 to 100 μm, and imidizing this. Substrates used when forming a film by this casting method include polymer films, glass plates, silicone rubber plates, and metal plates.

As a polymer film, for example, polyethylene terephthalate film A4100 (manufactured by Toyobo Corporation) can be used. In addition, when obtaining a green film of a certain thickness, a method of adjusting the concentration of the polyamic acid solution, a method of adjusting the gap between the coaters, or a method of repeating casting and laminating to achieve the desired film thickness can be adopted. Thereby, a substrate with a desired film thickness can be created. Additionally, the obtained green film can be thermally imidized by heat treatment to obtain a polyimide film.

The polyimide film may have a single-layer structure or a laminated structure of two or more layers. In view of the physical strength of the polyimide film and the ease of peeling from the inorganic substrate, a laminated structure of two or more layers is preferable, and a laminated structure of three or more layers is not a problem. In addition, in this specification, the physical properties (yellowness index, total light transmittance, haze, etc.) when the polyimide film has a laminated structure of two or more layers refer to the values of the entire polyimide film, unless otherwise specified.

The thickness of the polyimide film is preferably 5 μm or more, and more preferably 7 μm or more. The upper limit of the thickness of the polyimide film is not particularly limited, but for use as a flexible electronic device, it is preferably 200 μm or less, more preferably 90 μm or less, and still more preferably 50 μm or less. If it is too thin, film production and transportation will be difficult, and if it is too thick, roll transportation, etc. will be difficult.

The total light transmittance of the polyimide film in the present invention is preferably 75% or more, more preferably 85% or more, further preferably 87% or more, and even more preferably 88% or more. The upper limit of the total light transmittance of the polyimide film is not particularly limited, but for use as a flexible electronic device, it is preferably 98% or less, and more preferably 97% or less.

The haze of the polyimide film in the present invention is preferably 1.0 or less, more preferably 0.8 or less, further preferably 0.5 or less, and even more preferably 0.3 or less.

The yellowness index (hereinafter also referred to as “yellow index” or “YI”) of the polyimide film in the present invention is preferably 20 or less, more preferably 15 or less, further preferably 10 or less, and further more preferably 10 or less. Preferably it is 5 or less. The lower limit of the yellowness index of the polyimide film is not particularly limited, but for use as a flexible electronic device, it is preferably 0.1 or more, more preferably 0.2 or more, and even more preferably 0.3 or more.

The thickness direction retardation (Rth) of the polyimide film in the present invention is preferably 500 nm or less, more preferably 300 nm or less, further preferably 200 nm or less, and even more preferably 100 nm or less. The lower limit of Rth of the polyimide film is not particularly limited, but for use as a flexible electronic device, it is preferably 0.1 nm or more, and more preferably 0.5 nm or more.

Additionally, the polyimide film of the present invention can also be realized by stretching during the film formation process of the polyimide film. In this stretching operation, the polyimide solution is applied to a support for producing a polyimide film and dried to form a polyimide film containing 1 to 50% by mass of a solvent, and the polyimide solution is formed on the support for producing a polyimide film or peeled from the support. In the process of drying a polyimide film containing 1 to 50% by mass of a solvent at high temperature, it can be achieved by stretching from 1.5 to 4.0 times in the MD direction and from 1.4 to 3.0 times in the TD direction. At this time, an unstretched thermoplastic polymer film is used as a support for polyimide film production, the thermoplastic polymer film and the polyimide film are stretched simultaneously, and then the stretched polyimide film is peeled from the thermoplastic polymer film, especially during stretching in the MD direction. Damage to the polyimide film can be prevented, and a higher quality, colorless and highly transparent polyimide film can be obtained.

It is preferable that the average coefficient of linear expansion (CTE) of the polyimide film between 50°C and 200°C is 60 ppm/K or less. Preferably it is 50 ppm/K or less, more preferably 35 ppm/K or less. Additionally, it is preferably -20 ppm/K or more, and more preferably -10 ppm/K or more. If the CTE is within the above range, the difference in linear expansion coefficient with a general support (inorganic substrate) can be kept small, and peeling of the polyimide film and the inorganic substrate or bending of the support can be avoided even when subjected to a heat process. Here, CTE is a factor representing reversible expansion and contraction with respect to temperature. In addition, the method for measuring CTE of the polyimide film is the method described in the Examples.

The polyimide film may contain filler. The filler is not particularly limited and includes silica, carbon, ceramics, etc., and among these, silica is preferable. These fillers may be used individually, or two or more types may be used together. By adding filler, protrusions are provided on the surface of the polyimide film, thereby increasing the slipperiness of the surface of the polyimide film. Additionally, the CTE and Rth of the polyimide film can be suppressed low by adding filler. The average particle diameter of the filler is preferably 1 nm or more, and more preferably 5 nm or more. Additionally, it is preferably 1 μm or less, more preferably 500 nm or less, and even more preferably 100 nm or less.

The filler content in the polyimide film is preferably adjusted according to the average particle diameter of the filler. When the particle diameter of the filler is 30 nm or more, it is preferably 0.01 to 5 mass%, more preferably 0.01 to 3 mass%, further preferably 0.01 to 2 mass%, especially preferably 0.01 to 1 mass%. It is mass%. On the other hand, when the average particle diameter is less than 30 nm, it is preferably 0.01 to 50 mass%, more preferably 0.01 to 40 mass%, further preferably 0.01 to 30 mass%, and especially preferably 0.01 to 0.01 mass%. It is 20% by mass. By adjusting the content within the above range, the slipperiness of the surface of the polyimide film can be maintained high without impairing the transparency of the polyimide film, and the CTE and Rth of the polyimide film can be suppressed low.

The method of adding filler to the polyimide film is not particularly limited, but may include adding it as a powder when or after producing the polyamic acid (polyimide precursor) solution described above, or in the form of a filler/solvent (slurry). A method of adding it is included, and among these, a method of adding it as a slurry is particularly preferable. The slurry is not particularly limited, but is a slurry in which silica with an average particle diameter of 10 nm is dispersed in N,N-dimethylacetamide (DMAC) at a concentration of 20% by mass (for example, "Snowtex (registered trademark) DMAC-" manufactured by Nissan Chemical Industries, Ltd.) ST" or a slurry in which silica with an average particle diameter of 80 nm is dispersed in N,N-dimethylacetamide (DMAC) at a concentration of 20% by mass (e.g., "Snowtex (registered trademark) DMAC-ST- manufactured by Nissan Chemical Industries, Ltd.) ZL"), a slurry in which silica with an average particle diameter of 10 nm is dispersed in N-methylpyrrolidone (NMP) at a concentration of 20% by mass (for example, "Snowtex (registered trademark) NMP-ST" manufactured by Nissan Chemical Industries, etc.) I can hear it.

The polyimide film may contain a colorant. For example, the Y.I. of the film can be reduced by mixing a blue colorant with a light yellow polyimide film.

Colorants include, for example, organic pigments, inorganic pigments or dyes, but organic pigments and inorganic pigments are preferred in order to improve the heat resistance, reliability and light resistance of the colored film. From the viewpoint of heat resistance, it is preferable that the colorant has a 1% thermogravity reduction temperature of 220°C or higher. Additionally, the 1% thermogravity reduction temperature of the colorant can be measured using a TGA device (TGA-50, Shimadzu Seisakusho). In this measurement, approximately 10 mg of colorant is placed in an aluminum pan and measured at a temperature increase rate of 10°C/min under a nitrogen atmosphere. Then, starting from the weight when it reaches 150°C, read the temperature at which the weight decreases by 1% (1% weight loss temperature: Td ₁ ).

Examples of organic pigments include diketopyrrolopyrrole pigments; Azo pigments such as azo, disazo, and polyazo; Phthalocyanine-based pigments such as copper phthalocyanine, halogenated copper phthalocyanine, and metal-free phthalocyanine; Anthraquinone-based pigments such as aminoanthraquinone, diaminodianthraquinone, anthrapyrimidine, flavanthrone, anthanthrone, indanthrone, pyranthrone, and violanthrone; Quinacridone-based pigments; Dioxazine-based pigments; Perinone-based pigment; perylene-based pigment; Thioindigo pigments; Isoindoline pigments; Isoindolinone pigments; Quinophthalone pigments; srene-based pigment; Metal complex pigments, etc. can be mentioned.

Inorganic pigments include, for example, titanium oxide, zinc oxide, zinc sulfide, soft white, calcium carbonate, precipitated barium sulfate, white carbon, alumina white, kaolin clay, talc, bentonite, black iron oxide, cadmium red, bengala, molybdenum red, and molybdate orange. , chrome vermilion, yellow lead, cadmium yellow, yellow iron oxide, titanium yellow, chromium oxide, viridian, titanium cobalt green, cobalt green, cobalt chrome green, Victoria green, ultramarine blue, royal blue, cobalt blue, cellulian blue, cobalt silica blue. , cobalt zinc silica blue, manganese violet, cobalt violet, etc.

Examples of dyes include azo dyes, anthraquinone dyes, condensed polycyclic aromatic carbonyl dyes, indigoid dyes, carbonium dyes, phthalocyanine dyes, methine dyes, and polymethine dyes.

The tensile breaking strength of the polyimide film is preferably 60 MPa or more, more preferably 120 MPa or more, and even more preferably 160 MPa or more. The upper limit of the tensile breaking strength is not particularly limited, but is in fact less than about 1000 MPa. If the tensile breaking strength is 60 MPa or more, the polyimide film can be prevented from breaking when peeling from the inorganic substrate. In addition, the method for measuring the tensile breaking strength of the polyimide film is the method described in the Examples. In addition, even in the case of production after application on a glass substrate using a casting applicator, the two directions parallel to and perpendicular to the application with the casting applicator were defined as (MD direction) and (TD direction), respectively. Hereinafter, the same applies to tensile elongation at break and tensile modulus of elasticity.

The tensile elongation at break of the polyimide film is preferably 1% or more, more preferably 5% or more, and still more preferably 10% or more. If the tensile elongation at break is 5% or more, handleability is excellent. In addition, the method of measuring the tensile elongation at break of the polyimide film is based on the method described in the Examples.

The tensile modulus of elasticity of the polyimide film is preferably 2 GPa or more, more preferably 3 GPa or more, and still more preferably 4 GPa or more. If the tensile modulus is 3 GPa or more, the polyimide film undergoes little stretching strain when peeled from the inorganic substrate, and handling properties are excellent. The tensile modulus is preferably 20 GPa or less, more preferably 12 GPa or less, and even more preferably 10 GPa or less. If the tensile modulus is 20 GPa or less, the polyimide film can be used as a flexible film. In addition, the method of measuring the tensile modulus of elasticity of the polyimide film is based on the method described in the Examples.

Since the toughness of the polyimide film was improved while maintaining the tensile modulus to a certain degree, the tensile strength product, which is the product of tensile strength and elongation, was improved compared to the conventional polyimide film. That is, the tensile strength of the polyimide film of the present invention in the tensile test is preferably 300 MPa·% or more, more preferably 1,000 MPa·% or more, and still more preferably 1,200 MPa·% or more. The upper limit is not particularly set, but from the viewpoint of film handleability, it is preferable that the tensile product in the tensile test is 20,000 MPa·% or less. The term product may be, for example, 18,000 MPa·% or less, 15,000 MPa·% or less, and 10,000 MPa·% or less.

During its production, the polyimide film is preferably obtained in a wound form as a long polyimide film with a width of 300 mm or more and a length of 10 m or more, and is in the form of a roll-shaped polyimide film wound around a core. It is more desirable. If the polyimide film is wound in a roll shape, it becomes easy to transport in the form of a roll wound polyimide film.

In the above polyimide film, in order to ensure handling properties and productivity, about 0.03 to 3% by mass of a lubricant (particles) with a particle diameter of about 10 to 1000 nm is added or contained in the polyimide film to form a surface of the polyimide film. It is desirable to secure slipperiness by providing fine irregularities.

Additionally, when the polyimide film has a laminated structure of two or more layers, it is undesirable because the difference in CTE of each layer alone can cause warping. Therefore, the CTE difference between the first polyimide film layer in contact with the inorganic substrate and the second polyimide film layer adjacent to the first polyimide film without contact with the inorganic substrate is preferably 40 ppm/K or less. , more preferably 30 ppm/K or less, and even more preferably 15 ppm/K or less. In particular, it is preferable that the thickest layer of the second polyimide film is within the above range. In addition, it is preferable that the polyimide film has a symmetrical structure in the film thickness direction because it is difficult to cause bending.

In the polyimide film having a laminated structure of two or more layers, in particular, a first polyimide film layer in contact with the inorganic substrate and a second polyimide film layer adjacent to the first polyimide film layer (hereinafter simply referred to as “the first polyimide film layer”) 2 The thickness mixed at the interface of the polyimide film layer is not particularly limited as long as it is less than the sum of the thickness of one layer of the first polyimide film layer and the thickness of one layer of the second polyimide film layer. , it is preferably 99% or less of the sum of the thickness of one layer of the first polyimide film layer and the thickness of one layer of the second polyimide film layer, more preferably 80% or less, and even more preferably 50% or less. Additionally, there is no particular limitation regarding the lower limit, but industrially, there is no problem as long as it is 10 nm or more, and even if it is 20 nm or more, there is no problem. In addition, when there is a significant difference in the functions of each layer and it is necessary to fully exert each function without canceling it out, it is desirable to suppress the mixing area occupied by each layer to 50% or less, and to 30% or less. It is more preferable to do so, and it is even more preferable to suppress it to 10% or less.

The means for forming a low-mixing layer is not particularly limited, but rather than producing two layers of the first polyimide film layer and the second polyimide film layer simultaneously by solution film forming, the first polyimide film layer or the second polyimide film layer is used. It is desirable to produce one layer of the mid film layer and then produce the next layer after going through a heating process. The heating process includes both steps along the way and when it is completed. Making the next layer after the heating process is completed can result in less mixing, but the surface of the finished film often has already lost its reactivity, and since there are few functional groups on the surface, the adhesion between the two layers is weak, making it difficult for practical use. Sometimes problems arise. For this reason, even when mixing is small, an interface where mixing occurs for 10 nm or more is desirable.

It is also possible to produce a film with various properties by forming a two-layer film of materials (resins) with different physical properties. In addition, by laminating in a symmetrical structure in the thickness direction (e.g., first polyimide film layer/second polyimide film layer/first polyimide film layer), the balance of CTE of the entire film becomes good, and warping is less likely to occur. You can do it with film. In addition, it is conceivable to provide characteristic spectral characteristics by making one layer a layer that absorbs ultraviolet or infrared radiation, or to control the incidence and emission of light by using layers with different refractive indices. Additionally, by adding a lubricant to the first polyimide film layer, the slipperiness of the film can be improved while maintaining the optical and thermal properties of the entire film similar to those of the second polyimide film layer. In this case, the polymer composition of the first polyimide film layer and the second polyimide film layer may be the same or different.

As a means of producing a film with a layer structure of two or more layers, simultaneous coating using a T die capable of simultaneous discharge of two or more layers, sequential coating by applying the next layer after applying one layer, and drying after applying the first layer Various methods can be considered, such as a method of coating the next layer, a method of coating the next layer after completing the filmization of the first layer, or multilayering by heating laminate by adding a thermoplastic layer, but in this patent, the various existing coating methods are used. method, multi-layered methods can be appropriately introduced.

<Laminate>

The laminate of the present invention includes the polyimide film and an inorganic substrate as described above. Also in the above laminate, when the polyimide film is composed of two or more layers, at least one layer may contain the polyimide of the present invention. Additionally, in addition to the polyimide film, a transparent highly heat-resistant film other than the polyimide film may be laminated.

Examples of transparent high heat-resistant films include PET, PEN, PVC, acrylic, polystyrene, and polycarbonate. Transparent high heat-resistant film can be used on either side of the polyimide film.

A silane coupling agent layer, an adhesive layer, an adhesive layer, etc. may be further included between the polyimide film and the inorganic substrate. Additionally, the surface of the polyimide film may include a wiring layer, a conductive film layer, a metal layer, etc.

<Inorganic substrate>

The inorganic substrate may be any plate-shaped that can be used as a substrate containing an inorganic material, such as a substrate mainly made of glass plates, ceramic plates, semiconductor wafers, metals, etc., and composites of these glass plates, ceramic plates, semiconductor wafers, and metals. Examples include those in which they are laminated, those in which they are dispersed, and those in which these fibers are contained.

As the glass plate, quartz glass, high silica glass (96% silica), soda lime glass, lead glass, aluminoborosilicate glass, borosilicate glass (Pilex (registered trademark)), borosilicate glass (alkali-free), borosilicate glass (micro sheet), aluminosilicate glass, etc. Among these, those with a linear expansion coefficient of 5 ppm/K or less are preferable, and commercially available products include liquid crystal glass, such as "Corning (registered trademark) 7059" manufactured by Corning, "Corning (registered trademark) 1737", "EAGLE", and Asahi Glass. “AN100” manufactured by Nippon Denki Glass, “OA10, OA11G” manufactured by Nippon Denki Glass, and “AF32” manufactured by SCHOTT, etc. are preferred.

The semiconductor wafer is not particularly limited, but includes silicon wafer, germanium, silicon-germanium, gallium-arsenide, aluminum-gallium-indium, nitrogen-phosphorus-arsenic-antimony, SiC, InP (indium phosphorus), InGaAs, GaInNAs, LT. , LN, ZnO (zinc oxide), CdTe (cadmium telluride), and ZnSe (zinc selenide) wafers. Among these, the wafer used preferably is a silicon wafer, and a mirror-polished silicon wafer with a size of 8 inches or more is particularly preferable.

The metal includes single element metals such as W, Mo, Pt, Fe, Ni, and Au, and alloys such as Inconel, Monel, Nimonic, carbon copper, Fe-Ni-based Invar alloy, and super Invar alloy. It also includes multilayer metal plates made by adding other metal layers and ceramic layers to these metals. In this case, if the overall coefficient of linear expansion (CTE) with the additional layer is low, Cu, Al, etc. are also used in the main metal layer. The metal used as the additional metal layer is not limited as long as it has properties such as strong adhesion to the high heat-resistant film, no diffusion, good chemical resistance and heat resistance, but Cr, Ni, TiN, Mo Suitable examples include Cu-containing and the like.

Ceramic plates in the present invention include Al2O3, mullite, AlN, SiC, crystallized glass, cordierite, spodumene, Pb-BSG+CaZrO3+Al2O3, crystallized glass+Al2O3, crystallized Ca-BSG, BSG+Quartz, BSG. Includes base ceramics such as +Quartz, BSG+Al2O3, Pb-BSG+Al2O3, glass-ceramic, and zero the material.

It is preferable that the planar portion of the inorganic substrate is sufficiently flat. Specifically, the P-V value of the surface roughness is 50 nm or less, more preferably 20 nm or less, and even more preferably 5 nm or less. If it is rougher than this, the peeling strength between the polyimide film layer and the inorganic substrate may become insufficient.

The thickness of the inorganic substrate is not particularly limited, but from the viewpoint of handling, a thickness of 10 mm or less is preferable, 3 mm or less is more preferable, and 1.3 mm or less is still more preferable. The lower limit of the thickness is not particularly limited, but is preferably 0.07 mm or more, more preferably 0.15 mm or more, and even more preferably 0.3 mm or more. If it is too thin, it is easy to break, making handling difficult. Also, if it is too thick, it becomes heavy and difficult to handle.

<Formation of laminate>

The laminate of the present invention is preferably one in which the polyimide film and the inorganic substrate are laminated without substantially using an adhesive. When the polyimide film has a laminated structure of two or more layers, the first polyimide film is in contact with the inorganic substrate, and the second polyimide film layer is adjacent to the first polyimide film layer without contacting the inorganic substrate. It is preferable to contain. The second polyimide film may further have a plurality of laminated structures. Additionally, in the thickness direction of the laminate, there is no problem even if both ends are formed of an inorganic substrate (for example, an inorganic substrate/first polyimide film/second polyimide film/first polyimide film/inorganic substrate). In this case, the polyimide film and the inorganic substrate at both ends do not use substantially any adhesive.

The laminate may be formed by either producing a polyimide film and then laminating it with an inorganic substrate, or forming the polyimide film directly on the inorganic substrate or through another layer. When forming through another layer, it is preferable to interpose an easily peelable layer such as a silane coupling agent layer. Additionally, the inorganic substrate may be subjected to surface treatment to control the peeling force to an appropriate level.

The shape of the laminate is not particularly limited, and may be square or rectangular. It is preferably rectangular, and the length of the long side is preferably 300 mm or more, more preferably 500 mm or more, and still more preferably 1000 mm or more. The upper limit is not particularly limited, but it is desirable to be able to replace substrates of the size and material used industrially. Anything less than 20000 mm is sufficient, and even less than 10000 mm is not a problem.

The laminate of the present invention preferably has a warp amount of 10 mm or less when heated at 300°C. Since heat resistance becomes good, it is more preferably 8 mm or less, and even more preferably 6 mm or less. The lower limit of the amount of deflection is not particularly limited, but industrially, 0.01 mm or more is sufficient, and 0.1 mm or more is not a problem.

<Adhesive>

It is preferable that no adhesive layer is substantially interposed between the inorganic substrate and the polyimide film. Here, the adhesive layer referred to in the present invention refers to a Si (silicon) component containing less than 10% by mass (less than 10% by mass). In addition, not substantially used (not interposed) means that the thickness of the adhesive layer interposed between the inorganic substrate and the polyimide film is preferably 0.4 μm or less, more preferably 0.1 μm or less, and even more preferably 0.05 μm or less. It is ㎛ or less, particularly preferably 0.03 ㎛ or less, and most preferably 0 ㎛.

<Silane coupling agent (SCA)>

In the laminate, it is preferable to have a layer of silane coupling agent between the polyimide film and the inorganic substrate. In the present invention, a silane coupling agent refers to a compound containing 10% by mass or more of a Si (silicon) component. Additionally, it is preferable to have an alkoxy group in the structure. Additionally, it is preferable that a methyl group is not contained. By using a silane coupling agent layer, the intermediate layer between the polyimide film and the inorganic substrate can be thinned, so there are fewer outgassing components during heating, it is difficult to elute even in a wet process, and even if elution occurs, it remains in a trace amount. . Since the silane coupling agent improves heat resistance, it is preferable that it contains a large amount of silicon oxide component, and it is especially preferable that it has heat resistance at a temperature of about 400°C. The thickness of the silane coupling agent layer is preferably less than 0.2 μm. The range used as a flexible electronic device is preferably 100 nm or less (0.1 μm or less), more preferably 50 nm or less, and still more preferably 10 nm. When manufactured normally, it is about 0.10 ㎛ or less. Additionally, in processes where the silane coupling agent is desired to be as small as possible, even 5 nm or less can be used. If it is 1 nm or less, there is a risk that the peeling strength may decrease or partially non-stick portions may appear, so it is preferable that it is 1 nm or more.

The silane coupling agent in the present invention is not particularly limited, but preferably has an amino group or an epoxy group. Specific examples of silane coupling agents include N-2-(aminoethyl)-3-aminopropylmethyldimethoxysilane, N-2-(aminoethyl)-3-aminopropyltrimethoxysilane, and N-2-(aminoethyl )-3-Aminopropyltriethoxysilane, 3-aminopropyltrimethoxysilane, 3-aminopropyltriethoxysilane, 3-triethoxysilyl-N-(1,3-dimethyl-butylidene)propyl Amine, 2-(3,4-epoxycyclohexyl)ethyltrimethoxysilane, 3-glycidoxypropyltrimethoxysilane, 3-glycidoxypropylmethyldiethoxysilane, 3-glycidoxypropyltriethoxy Silane vinyltrichlorosilane, vinyltrimethoxysilane, vinyltriethoxysilane, 2-(3,4-epoxycyclohexyl)ethyltrimethoxysilane, 3-glycidoxypropyltrimethoxysilane, 3-glycidoxysilane Doxypropylmethyldiethoxysilane, 3-glycidoxypropyltriethoxysilane, p-styryltrimethoxysilane, 3-methacryloxypropylmethyldimethoxysilane, 3-methacryloxypropyltrimethoxysilane, 3 -Methacryloxypropylmethyldiethoxysilane, 3-methacryloxypropyltriethoxysilane, 3-acryloxypropyltrimethoxysilane, N-phenyl-3-aminopropyltrimethoxysilane, N-(vinylbenzyl) -2-Aminoethyl-3-aminopropyltrimethoxysilane hydrochloride, 3-ureidopropyltriethoxysilane, 3-chloropropyltrimethoxysilane, 3-mercaptopropylmethyldimethoxysilane, 3-mercapto Propyltrimethoxysilane, bis(triethoxysilylpropyl)tetrasulfide, 3-isocyanate propyltriethoxysilane, tris(3-trimethoxysilylpropyl)isocyanurate, chloromethylphenethyltrimethoxysilane, Chloromethyltrimethoxysilane, etc. are mentioned. Among these, preferred ones include N-2-(aminoethyl)-3-aminopropylmethyldimethoxysilane, N-2-(aminoethyl)-3-aminopropyltrimethoxysilane, and N-2-(aminoethyl). -3-Aminopropyltriethoxysilane, 3-aminopropyltrimethoxysilane, 3-aminopropyltriethoxysilane, 3-triethoxysilyl-N-(1,3-dimethyl-butylidene)propylamine , 2-(3,4-epoxycyclohexyl)ethyltrimethoxysilane, 3-glycidoxypropyltrimethoxysilane, 3-glycidoxypropylmethyldiethoxysilane, 3-glycidoxypropyltriethoxysilane , aminophenyltrimethoxysilane, aminophenethyltrimethoxysilane, aminophenylaminomethylphenethyltrimethoxysilane, etc. When heat resistance is required in the process, it is preferable to link Si and amino groups etc. with aromatics.

The peel strength of the polyimide film and the inorganic substrate needs to be 0.3 N/cm or less. Accordingly, after forming a device on a polyimide film, peeling of the polyimide film and the inorganic substrate becomes very easy. Therefore, it is possible to manufacture a device connection that can be mass-produced, making it easy to manufacture flexible electronic devices. The peel strength is preferably 0.25 N/cm or less, more preferably 0.2 N/cm or less, further preferably 0.15 N/cm or less, and particularly preferably 0.12 N/cm or less. Additionally, it is preferably 0.03 N/cm or more. Since the laminate does not peel when forming a device on a polyimide film, it is more preferably 0.06 N/cm or more, further preferably 0.08 N/cm or more, and especially preferably 0.1 N/cm or more. The peel strength is the value of the laminate after the polyimide film and the inorganic substrate are bonded together and then heat treated at 100°C for 10 minutes in an air atmosphere (initial peel strength). In addition, it is preferable that the peel strength of the laminate at the time of the initial peel strength measurement and the laminate after heat treatment at 300°C for 1 hour in a nitrogen atmosphere is within the above range (peel strength after heat treatment at 300°C).

The laminate of the present invention can be produced, for example, by the following procedures. A laminate can be obtained by treating at least one side of the inorganic substrate in advance with a silane coupling agent, overlapping the silane coupling agent-treated side with a polyimide film, and laminating them by pressing. Additionally, a laminate can be obtained by treating at least one side of the polyimide film in advance with a silane coupling agent, overlapping the silane coupling agent-treated side with an inorganic substrate, and laminating both by pressing. Additionally, when the polyimide film has a laminated structure of two or more layers, it is preferable to overlap the first polyimide film on the inorganic substrate. Pressing methods include normal press or laminate in air or press or laminate in vacuum. However, in order to obtain stable peeling strength of the entire surface, for large-sized laminates (e.g., exceeding 200 mm), laminate in air is required. desirable. In contrast, if the laminate is small in size, about 200 mm or less, pressing in a vacuum is preferable. The vacuum level using a normal oil rotary pump is sufficient, and 10 Torr or less is sufficient. Preferred pressures are 1 MPa to 20 MPa, and more preferably 3 MPa to 10 MPa. If the pressure is high, there is a risk of damaging the substrate, and if the pressure is low, there may be parts that do not adhere well. The preferred temperature is 90°C to 500°C, more preferably 100°C to 400°C. If the temperature is high, the film may be damaged, and if the temperature is low, the adhesion may be weak.

<Method for manufacturing flexible electronic devices>

The manufacturing method of the flexible electronic device of the present invention includes a step of forming an electronic device on the polyimide film surface of the laminate of the present invention and a step of peeling off the inorganic substrate. In this way, a flexible electronic device in which the electronic device is formed on the polyimide film surface can be manufactured.

Therefore, the flexible electronic device of the present invention includes the polyimide film of the present invention and an electronic device formed on the polyimide film.

Using the above laminate, flexible electronic devices can be easily manufactured using existing electronic device manufacturing equipment and processes. Specifically, a flexible electronic device can be produced by forming an electronic device on a polyimide film of a laminated body and peeling each polyimide film from the laminated body.

In this specification, an electronic device refers to a wiring board with a single-sided, double-sided, or multi-layer structure responsible for electrical wiring, an electronic circuit including active elements such as transistors and diodes, passive devices such as resistors, capacitors, and inductors, and other pressure devices. , sensor elements that sense temperature, light, humidity, etc., biosensor elements, light-emitting elements, image display elements such as liquid crystal displays, electrophoretic displays, and self-luminous displays, wireless and wired communication elements, computing elements, memory elements, This refers to MEMS devices, solar cells, thin film transistors, etc.

Additionally, an interposer function, which is an electrode that penetrates the polyimide within this wiring board, is also included. By roughly penetrating, the process of manufacturing a penetrating electrode after peeling off the inorganic substrate is largely omitted. A known method can be used to make the through hole. For example, a through hole is created in a polyimide film using a UV nano laser. Next, for example, by applying a method used for through holes in a double-sided printed wiring board or via holes in a multilayer printed wiring board, the through holes are filled with a conductive metal, and a wiring pattern using the metal that meets the needs is formed. there is.

In the case of polyimide film, as described above, there may be cases where the through electrode is drilled and then bonded to an inorganic substrate. There may be cases where a penetrating electrode is manufactured after bonding an inorganic substrate and a polyimide film. Although it is possible to penetrate the polyimide film and metallize it, it is also possible to make a hole from one side of the polyimide film and metallize it without penetrating into the surface of the opposite side.

<Process of peeling off the inorganic substrate>

The method for manufacturing a flexible electronic device of the present invention includes forming an electronic device on the polyimide film surface of the laminate and then peeling off the inorganic substrate. When peeling the inorganic substrate, in addition to peeling at the interface between the polyimide film and the inorganic substrate, peeling together with one or more layers of a polyimide film composed of two or more layers, or peeling the inorganic substrate together with any other layer It is also possible to do so.

In the case of peeling at the interface between the polyimide film and the inorganic substrate, that is, the method of peeling the device-equipped polyimide film from the inorganic substrate is not particularly limited, but may include lifting from the end with tweezers or the like, or making a cut in the polyimide film. , a method of attaching an adhesive tape to one side of the incised portion and then lifting it up from the tape portion, or a method of vacuum suctioning one side of the incised portion of the polyimide film and then lifting it up from that portion, etc. can be adopted. Additionally, during peeling, if a bend with a small curvature occurs at the cut portion of the polyimide film, stress is applied to the device at that portion and there is a risk of destroying the device, so it is preferable to peel it off with as much curvature as possible. For example, it is preferable to roll up while winding on a roll with a large curvature, or to roll up using a machine configured such that a roll with a large curvature is located at the peeling portion.

Methods for making incisions in the polyimide film include a method of cutting the polyimide film with a cutting tool such as a blade, a method of cutting the polyimide film by relatively scanning the laser and the laminate, and a water jet and the laminate. There is a method of cutting the polyimide film by relatively scanning, a method of cutting the polyimide film while slightly cutting into the glass layer using a semiconductor chip dicing device, etc., but the method is not particularly limited. For example, when employing the above-described method, methods such as superimposing ultrasonic waves on the cutting tool or improving cutting performance by adding reciprocating motion, up and down motion, etc. may be appropriately employed.

Additionally, a method of attaching a separate reinforcing base material in advance to the area to be peeled off and peeling off each reinforcing base material is also useful. When the flexible electronic device to be peeled is the backplane of a display device, the front plane of the display device can be bonded in advance, integrated on an inorganic substrate, and then both can be peeled off simultaneously to obtain a flexible display device.

In addition, when peeling an inorganic substrate together with one or more layers of a polyimide film composed of two or more layers, the peeling force of the interface of the polyimide film composed of two or more layers is such that a light peeling force is obtained from the interface with the inorganic substrate. After adjusting, it can be peeled in the same manner as described above. The peeling force at the interface of the polyimide film can be adjusted according to the type of polyimide in each layer or the degree of imidization of the lower layer when applying the upper layer.

When peeling the inorganic substrate together with other optional layers, an adhesive layer, etc., which has a higher adhesion with the inorganic substrate and an adjusted peeling force with the polyimide film, can be formed and then peeled in the same manner as the above-mentioned method. .

Example

Hereinafter, the present invention will be described in detail using examples, but the present invention is not limited to the following examples as long as it does not depart from the gist of the invention. In addition, each physical property in the synthesis examples and examples was measured by the following method.

<Measurement of thickness of polyimide film>

The thickness of the film was measured using a micrometer (Militron 1245D, manufactured by Pineleup Co., Ltd.). Additionally, the same measurement was performed three times, and the arithmetic mean value was adopted.

<Total light transmittance>

The total light transmittance (TT) of the film was measured using HAZEMETER (NDH5000, manufactured by Nippon Denshoku Corporation). A D65 lamp was used as the light source. Additionally, the same measurement was performed three times, and the arithmetic mean value was adopted.

<Haize>

The haze of the film was measured using HAZEMETER (NDH5000, Nippon Denshoku Corporation Zero). A D65 lamp was used as the light source. Additionally, the same measurement was performed three times, and the arithmetic mean value was adopted.

<Yellow Index>

Using a color meter (ZE6000, Nippon Denshoku Corporation Zero) and C2 light source, the tristimulus value XYZ values of the film were measured according to ASTM D1925, and the yellowness index (YI) was calculated using the following formula. Additionally, the same measurement was performed three times, and the arithmetic mean value was adopted.

YI=100×(1.28X-1.06Z)/Y

<Refractive index, retardation (Rth)>

The refractive index was measured using an Abbe refractometer (NAR-4T, ATAGO), and the in-plane phase difference Rth was calculated. Specifically, the refractive index (Nx, Nz) and (Ny, Nz) of the film were measured, respectively, and ΔP was calculated using the following formula. Additionally, the in-plane retardation Rth (nm) was calculated by multiplying ΔP by the film thickness (unit ㎛). At this time, Rth is expressed as the average value of the front and back sides of the film.

ΔP=(Nx+Ny)/2-Nz

Rth(nm)=ΔP×thickness×1000

Pyrolysis temperature (Td ₁ )

It was measured using a TGA device (TGA-50, Shimadzu Seisakusho). The measurement was performed by placing about 10 mg of film on an aluminum pan and carrying out a temperature increase rate of 10°C/min under a nitrogen atmosphere. Starting from the weight when it reached 150°C, the temperature at which the weight decreased by 1% (1% weight loss temperature: Td ₁ ) was read.

<Glass transition temperature (Tg), coefficient of linear expansion (CTE)>

Measured using TMA (TMA4000S, BRUKER AXIS). The film was cut into segments of 15 mm in width x 2 mm in length, and set in the device with 10 mm between chucks and a load of 5 gf. Under an argon atmosphere, the temperature was raised to 250°C at a rate of 20°C/min, and then lowered to 30°C at a rate of 5°C/min. After that, the temperature was raised at 10°C/min to the temperature at which thermal decomposition did not occur (Td1-20°C). CTE was calculated from the slope in the 200°C to 50°C section when the temperature was lowered, and the inflection point at the second temperature increase was set as Tg.

<Tensile modulus, tensile strength, elongation, tensile product>

The test was conducted as follows using Tensilon (Autograph AG-IS, Shimadzu Seisakusho). The film was cut into segments of 5 mm x 50 mm in length in the flow direction (MD direction) at the time of application, which were used as test pieces. 30 mm of both ends of the segment were gripped with an air jaw chuck, and the tensile modulus of elasticity in the MD direction, tensile strength at break, and elongation at break were determined at room temperature and under the condition of a tensile speed of 50 mm/min. The tensile modulus was obtained from the initial elastic gradient of the strain-stress curve. Measurements were performed at each level N = 5, and the average value of 3 points excluding the maximum and minimum values was treated as data. The product of the tensile strength at break and the elongation at break was taken as the length product.

< ¹ H NMR measurement of silsesquioxane compound having an acid anhydride group>

¹ H NMR measurement was performed using each sample under the following conditions.

Apparatus: DPX400 manufactured by Bruker Biospin (Examples 1 to 2) or 400MR manufactured by Agilent (Examples 3 to 9)

Solvent: deuterated chloroform (CDCl ₃ ) (Examples 1 to 2) or deuterated DMSO (DMSO-d ₆ ) (Examples 3 to 9)

Sample concentration: 3 mg/1 mL

Measurement temperature: room temperature (24℃)

Resonant frequency: 400 MHz

Integration count: 32 times

Examples 1 to 9 and Comparative Examples 1 to 6 and 8

First, Examples 1 to 9 and Comparative Examples 1 to 6 and 8 will be described. Specifically, these will be explained regarding the synthesis of silsesquioxane compounds, synthesis of polyamic acid solutions, preparation of polyimide films, various evaluation results, etc.

[Synthesis Example 1-1: Synthesis of thiol group-containing silsesquioxane compound 1]

In a reaction apparatus equipped with a stirrer, cooling tube, fountain, thermometer, dropping funnel, and nitrogen inlet, 11.8 g (60.0 mmol) of 3-mercaptopropyltrimethoxysilane and 2.72 g (20.0 mmol) of methyltrimethoxysilane ( [Number of moles of component (a2)]/[Total number of moles of component (a1) and component (a2)]=0.25), ion-exchanged water 1.9 g ([Number of moles of water used for hydrolysis reaction]/[Component (a1), ( [sum of moles of alkoxy groups contained in a2)] (molar ratio) = 0.45), 1.0 g of cation exchange resin was injected, and hydrolysis reaction was performed at room temperature for 30 minutes. After the reaction, the cation exchange resin was filtered and diluted with 5 g of ethylene glycol dimethyl ether (DMG) to obtain a hydrolyzate solution.

Next, 9 g of DMG and 0.05 g of 25% tetramethylammonium hydroxide aqueous solution were injected into a separate reaction vessel, and heated to 80°C. The above hydrolyzate solution was added dropwise over a period of 2 hours and 30 minutes. Tetramethylammonium hydroxide was dissolved during the dropwise addition, and the reaction liquid became clear. After dropwise addition, reaction was performed at 80°C for another 15 minutes and then cooled to 25°C. 0.5 g of cation exchange resin was injected here, and stirred at room temperature for 4 hours. Tetramethylammonium hydroxide was adsorbed during stirring, and the reaction liquid became clear. By filtering and fractionating the cation exchange resin, a solution of thiol group-containing silsesquioxane (average number of thiol groups per molecule = 6) was obtained. Toluene was added and heated to 70°C under reduced pressure to distill off some of the methanol, water, and toluene generated by hydrolysis. Toluene was added appropriately to adjust the final solid concentration to 72%.

[Synthesis Example 1-2: Synthesis of thiol group-containing silsesquioxane compound 2]

8.83 g (45.0 mmol) of 3-mercaptopropyltrimethoxysilane, 5.44 g (40.0 mmol) of methyltrimethoxysilane ([number of moles of component (a2)]/[sum of moles of component (a1) and component (a2) ]=0.47), except that 2.0 g of ion-exchanged water ([number of moles of water used in the hydrolysis reaction]/[sum of moles of alkoxy groups contained in components (a1) and (a2)] (molar ratio)=0.45) It was synthesized in the same manner as Synthesis Example 1-1. The average number of thiol groups per molecule of the obtained thiol group-containing silsesquioxane was 4.5, and the final solid concentration was 72% by mass.

[Synthesis Example 1-3: Synthesis of thiol group-containing silsesquioxane compound 3]

4.91 g (25.0 mmol) of 3-mercaptopropyltrimethoxysilane, 6.81 g (50.0 mmol) of methyltrimethoxysilane ([number of moles of component (a2)]/[sum of moles of component (a1) and component (a2) ]=0.67) Synthesis other than 1.8 g of ion-exchanged water ([number of moles of water used for hydrolysis reaction]/[sum of number of moles of alkoxy groups contained in components (a1) and (a2)] (molar ratio) = 0.45) It was synthesized in the same manner as Example 1-1. The average number of thiol groups per molecule of the obtained thiol group-containing silsesquioxane was 2.5, and the final solid concentration was 72% by mass.

[Synthesis Example 2-1: Synthesis of silsesquioxane SQ1 having an acid anhydride group]

Add 10 g (thiol group amount: 16.7 mmol) of the following thiol group-containing silsesquioxane solution (Composeran SQ-109, manufactured by Arakawa Chemical Co., Ltd.) and 2.74 g (16.7 mmol) of norbornene acid anhydride into a reaction vessel. By irradiating ultraviolet light (Spotcure SP-11, manufactured by USHIO) for 20 minutes while stirring, silsesquioxane SQ1 having an acid anhydride group was obtained as a colorless and transparent solution. NMR and IR measurements confirmed that the thiol group and norbornene were reacting. The obtained solution was filtered through a PTFE filter (pore diameter: 10 μm) and then used for the synthesis of a polyamic acid solution described later (the same applies to SQ3 to SQ9).

Composceran SQ-109: condensate of methyltrimethoxysilane and 3-mercaptopropyltrimethoxysilane, molar ratio (electron/(electron + latter)) = 2/8, solvent PGMEA, solid content concentration 25% by mass.

In addition, the molar ratio and average number of thiol groups per molecule were calculated as follows. In the ¹ H NMR measurement of compoceran SQ-109, from the integration ratio of the proton derived from the methyl group (around δ = 0.0 to 0.2, 3H) and the proton derived from the propylthiol group (around δ = 0.2 to 0.8, 2H), methyl The molar ratio of trimethoxysilane and 3-mercaptopropyltrimethoxysilane was calculated. The average number of thiol groups per molecule is the ratio of the thiol group to the methyl group, molecular weight per structural unit (SiO _1.5 Me = 67.1, SiO _1.5 C ₃ H ₆ SH = 127.2), thiol group equivalent in solution (600 g/eq.), It was calculated from a solid content concentration of 25% by mass.

For reference, the NMR measurement results are shown in FIGS. 1 to 4. Figure 1 shows the ¹ H NMR (CDCl ₃ ) spectrum for SQ-109 (PGMEA solution, Figure 2 for PGMEA, Figure 3 for norbornene anhydride, and Figure 4 for the reaction mixture after reaction. In Figure 4, The peak (δ = 6.3, etc.) derived from the double bond of norbornene anhydride has disappeared, so it is thought that the reaction between the thiol group and the double bond has progressed.

[Synthesis Example 2-2: Synthesis of silsesquioxane SQ2 having an acid anhydride group]

10 g of thiol group-containing silsesquioxane solution (Composeran SQ-109, manufactured by Arakawa Chemical Co., Ltd. (thiol group amount: 16.7 mmol), norbornene anhydride 2.74 g (16.7 mmol), iron (III) chloride 1 mg. was placed in a reaction vessel and stirred for 10 minutes to obtain silsesquioxane SQ2 having an acid anhydride group as a pale yellow solution (yellow coloring is thought to originate from iron chloride). NMR and IR measurements confirmed that the thiol group and norbornene were reacting.

For reference, FIG. 5 shows the ¹ H NMR (CDCl ₃ ) spectrum of the reaction mixture after the reaction as an NMR measurement result. In Figure 5, the peak (δ = 6.3, etc.) derived from the double bond of norbornene anhydride has disappeared, so it is believed that the reaction between the thiol group and the double bond has progressed.

[Synthesis Example 2-3: Synthesis of silsesquioxane SQ3 having an acid anhydride group]

20 g (thiol group amount: 97.0 mmol) of the solution of thiol group-containing silsesquioxane compound 1 obtained in Synthesis Example 1-1, 15.9 g (97.0 mmol) of norbornene anhydride, and 10.0 g of PGMEA were added to a reaction vessel and stirred. By irradiating ultraviolet light (Spotcure SP-11, manufactured by USHIO) for 20 minutes, silsesquioxane SQ3 having an acid anhydride group was obtained as a colorless and transparent solution. NMR and IR measurements confirmed that the thiol group and norbornene were reacting.

[Synthesis Example 2-4: Synthesis of silsesquioxane SQ4 having an acid anhydride group]

20 g (thiol group amount: 77.9 mmol) of the solution of thiol group-containing silsesquioxane compound 2 obtained in Synthesis Example 1-2, 12.8 g (77.9 mmol) of norbornene anhydride, and 10.0 g of PGMEA were added to a reaction vessel and stirred. By irradiating ultraviolet light (Spotcure SP-11, manufactured by USHIO) for 20 minutes, silsesquioxane SQ4 having an acid anhydride group was obtained as a colorless and transparent solution. NMR and IR measurements confirmed that the thiol group and norbornene were reacting.

[Synthesis Example 2-5: Synthesis of silsesquioxane SQ5 having an acid anhydride group]

The solution of thiol group-containing silsesquioxane compound 3 obtained in Synthesis Example 1-3 was mixed with 20 g (thiol group amount: 54.5 mmol), 8.95 g (54.5 mmol) of 5-norbornene-2,3-dicarboxylic anhydride, 10.0 g of PGMEA was placed in a reaction vessel and irradiated with ultraviolet light (Spotcure SP-11, manufactured by USHIO) for 20 minutes while stirring to obtain silsesquioxane SQ5 having an acid anhydride group as a colorless transparent solution. NMR and IR measurements confirmed that the thiol group and 5-norbornene-2,3-dicarboxylic anhydride were reacting.

[Synthesis Example 2-6: Synthesis of silsesquioxane SQ6 having an acid anhydride group]

Add 6 g (thiol group amount: 10.0 mmol) of thiol group-containing trialkoxysilane solution (Composeran SQ-109, manufactured by Arakawa Chemical Co., Ltd.) and 1.40 g (10.0 mmol) of allyl succinic anhydride into a reaction vessel, and stir while stirring. By irradiating with external light (Spotcure SP-11, manufactured by USHIO) for 20 minutes, silsesquioxane SQ6 having an acid anhydride group was obtained as a colorless transparent solution. NMR and IR measurements confirmed that the thiol group and allylsuccinic anhydride were reacting.

[Synthesis Example 2-7: Synthesis of silsesquioxane SQ7 having an acid anhydride group]

thiol group-containing trialkoxysilane solution (Composeran SQ-109, manufactured by Arakawa Chemical Co., Ltd.) 6 g (thiol group amount 10.0 mmol), exo-3,6-epoxy-1,2,3,6-tetrahydro 1.66 g (10.0 mmol) of phthalic anhydride was placed in a reaction vessel and irradiated with ultraviolet light (Spotcure SP-11, manufactured by USHIO) for 20 minutes while stirring to obtain silsesquioxane SQ7 having an acid anhydride group as a colorless transparent solution. . By NMR and IR measurements, it was confirmed that the thiol group and exo-3,6-epoxy-1,2,3,6-tetrahydrophthalic anhydride were reacting.

[Synthesis Example 2-8: Synthesis of silsesquioxane SQ8 having an acid anhydride group]

Thiol group-containing trialkoxysilane solution (Composeran SQ-109 manufactured by Arakawa Chemical Co., Ltd.) 3 g (thiol group amount 5.0 mmol), 5,6-dihydro-1,4-dithiine-2,3- 0.94 g (5.0 mmol) of dicarboxylic acid anhydride and γ-butyrolactone (5 mL) were placed in a reaction vessel, and irradiated with ultraviolet light (Spotcure SP-11, manufactured by USHIO) for 20 minutes while stirring, until colorless and transparent. Silsesquioxane SQ8 having an acid anhydride group was obtained as a solution. NMR and IR measurements confirmed that the thiol group and 5,6-dihydro-1,4-dithiine-2,3-dicarboxylic anhydride were reacting.

[Synthesis Example 2-9: Synthesis of silsesquioxane SQ9 having an acid anhydride group]

Add 6 g (thiol group amount: 10.0 mmol) of trialkoxysilane solution containing a thiol group (Composeran SQ-109, manufactured by Arakawa Chemical Co., Ltd.) to a reaction vessel, and add 2.10 g (10.0 mmol) of trimellitic anhydride chloride while stirring. ) was added slowly. By stirring at room temperature for 24 hours, silsesquioxane SQ9 having an acid anhydride group was obtained as a colorless and transparent solution. By NMR and IR measurements, it was confirmed that the thiol group and the acid chloride group were reacting.

[Example A: Synthesis of polyamic acid solution A]

While passing nitrogen through a reactor equipped with a nitrogen introduction pipe and stirring blade, 1,2,3,4-cyclobutanetetracarboxylic dianhydride (CBDA, 5.88 g), 4,4'-diamino-2,2'- Bis(trifluoromethyl)biphenyl (TFMB, 9.74 g) and SQ1 solution (0.655 g) were added, dissolved in N,N-dimethylacetamide (DMAc, 125.0 g), and stirred at 25°C for 24 hours to obtain poly Amic acid solution A was obtained (molar ratio of CBDA/SQ1/TFMB=0.985/0.015/1.00). Here, the molar ratio of SQ1 is a value calculated based on the acid anhydride group divalent sugar, and specifically, the total number of moles of unit structures derived from the silsesquioxane compound is divided by the total number of dicarboxylic acid anhydride groups. It is calculated as a number doubled (the same applies to the mole ratio below).

[Example B: Synthesis of polyamic acid solution B]

While passing nitrogen through a reactor equipped with a nitrogen introduction pipe and stirring blade, 1,2,3,4-cyclobutanetetracarboxylic dianhydride (CBDA, 5.88 g) and 4,4'-diaminobenzanilide (DABA, 6.92 g) g), SQ1 solution (0.655 g) was added, dissolved in N,N-dimethylacetamide (DMAc, 133.7 g), and stirred at 25°C for 24 hours to obtain polyamic acid solution B (CBDA/SQ1/DABA molar ratio=0.985/0.015/1.00).

[Example Ca: Synthesis of polyamic acid solution Ca]

Pyromellitic dianhydride (PMDA, 3.27 g) and 4,4'-diamino-2,2'-bis(trifluoromethyl)biphenyl (TFMB) were passed through nitrogen through a reactor equipped with a nitrogen introduction pipe and stirring blade. , 4.88 g) and SQ1 solution (0.328 g) were added, dissolved in N,N-dimethylacetamide (DMAc, 67.0 g), and stirred at 25°C for 24 hours to obtain polyamic acid solution Ca (PMDA/SQ1/ Molar ratio of TFMB = 0.985/0.015/1.00).

[Example Cb: Synthesis of polyamic acid solution Cb]

Pyromellitic dianhydride (PMDA, 3.27 g) and 4,4'-diamino-2,2'-bis(trifluoromethyl)biphenyl (TFMB) were passed through nitrogen through a reactor equipped with a nitrogen introduction pipe and stirring blade. , 4.90 g) and SQ3 solution (0.227 g) were added, dissolved in N-methyl-2-pyrrolidone (NMP, 66.0 g), and stirred at 25°C for 24 hours to obtain polyamic acid solution Cb (PMDA/ Molar ratio of SQ3/TFMB = 0.98/0.02/1.00).

[Example Cc: Synthesis of polyamic acid solution Cc]

Pyromellitic dianhydride (PMDA, 3.27 g) and 4,4'-diamino-2,2'-bis(trifluoromethyl)biphenyl (TFMB) were passed through nitrogen through a reactor equipped with a nitrogen introduction pipe and stirring blade. , 4.90 g) and SQ4 solution (0.258 g) were added, dissolved in N-methyl-2-pyrrolidone (NMP, 66.0 g), and stirred at 25°C for 24 hours to obtain polyamic acid solution Cc (PMDA/ Molar ratio of SQ4/TFMB = 0.98/0.02/1.00).

[Example Cd: Synthesis of polyamic acid solution Cd]

Pyromellitic dianhydride (PMDA, 3.27 g) and 4,4'-diamino-2,2'-bis(trifluoromethyl)biphenyl (TFMB) were passed through nitrogen through a reactor equipped with a nitrogen introduction pipe and stirring blade. , 4.90 g) and SQ5 solution (0.325 g) were added, dissolved in N-methyl-2-pyrrolidone (NMP, 66.0 g), and stirred at 25°C for 24 hours to obtain polyamic acid solution Cd (PMDA/ molar ratio of SQ5/TFMB=0.98/0.02/1.00).

[Example Ce: Synthesis of polyamic acid solution Ce]

Pyromellitic dianhydride (PMDA, 3.27 g) and 4,4'-diamino-2,2'-bis(trifluoromethyl)biphenyl (TFMB) were passed through nitrogen through a reactor equipped with a nitrogen introduction pipe and stirring blade. , 4.90 g) and SQ9 solution (0.354 g) were added, dissolved in N-methyl-2-pyrrolidone (NMP, 66.0 g), and stirred at 25°C for 24 hours to obtain polyamic acid solution Ce (PMDA/ Molar ratio of SQ9/TFMB=0.985/0.015/1.00).

[Example D: Synthesis of polyamic acid solution D]

Pyromellitic dianhydride (PMDA, 3.27 g), 4,4'-diaminobenzanilide (DABA, 3.47 g), and SQ1 solution (0.328 g) were added while passing nitrogen through a reactor equipped with a nitrogen introduction tube and stirring blade. , was dissolved in N,N-dimethylacetamide (DMAc, 63.0 g), and then stirred at 25°C for 24 hours to obtain polyamic acid solution D (molar ratio of PMDA/SQ1/DABA = 0.985/0.015/1.00).

[Comparative Example A1: Synthesis of polyamic acid solution A1]

1,2,3,4-cyclobutanetetracarboxylic dianhydride (CBDA, 19.6 g), 4,4'-diamino-2,2'- while passing nitrogen through a reactor equipped with a nitrogen introduction pipe and stirring blade. Bis(trifluoromethyl)biphenyl (TFMB, 32.3 g) was added, dissolved in N,N-dimethylacetamide (DMAc, 279.0 g), and stirred at 25°C for 24 hours to obtain polyamic acid solution A1 ( Molar ratio of CBDA/TFMB=1.00/1.00).

[Comparative Example B1: Synthesis of polyamic acid solution B1]

1,2,3,4-cyclobutanetetracarboxylic dianhydride (CBDA, 3.98 g) and 4,4'-diaminobenzanilide (DABA, 4.58 g) were passed through nitrogen through a reactor equipped with a nitrogen introduction pipe and stirring blade. g) was added, dissolved in N,N-dimethylacetamide (DMAc, 76.0 g), and then stirred at 25°C for 24 hours to obtain polyamic acid solution B1 (molar ratio of CBDA/DABA = 1.00/1.00).

[Example B2: Synthesis of polyamic acid solution B2]

1,2,3,4-cyclobutanetetracarboxylic dianhydride (CBDA, 2.94 g) and 4,4'-diaminobenzanilide (DABA, 3.54 g) were passed through nitrogen through a reactor equipped with a nitrogen introduction pipe and stirring blade. g), SQ1 solution (1.00 g) was added, dissolved in N,N-dimethylacetamide (DMAc, 90 g), and then stirred at 25°C for 24 hours to obtain polyamic acid solution B2 (CBDA/SQ1/DABA molar ratio=0.955/0.045/1.00).

[Comparative Example B4: Synthesis of polyamic acid solution B4]

While passing nitrogen through a reactor equipped with a nitrogen introduction pipe and stirring blade, 1,2,3,4-cyclobutanetetracarboxylic dianhydride (CBDA, 3.98 g) and 4,4'-diaminobenzanilide (DABA, 4.55 g) g) was added, dissolved in N,N-dimethylacetamide (DMAc, 76.0 g), and then stirred at 25°C for 24 hours. After that, SQ-109 (0.546 g) was added and stirred for 24 hours to obtain polyamic acid solution B4 (molar ratio of CBDA/DABA/SQ-109 = 1.00/1.00/0.01).

[Comparative Example B5: Synthesis of polyamic acid solution B5]

While passing nitrogen through a reactor equipped with a nitrogen introduction pipe and stirring blade, 1,2,3,4-cyclobutanetetracarboxylic dianhydride (CBDA, 3.98 g) and 4,4'-diaminobenzanilide (DABA, 4.55 g) g) was added, dissolved in N,N-dimethylacetamide (DMAc, 76.0 g), and then stirred at 25°C for 24 hours. After that, SQ-109 (8.19 g) was added and stirred for 24 hours to obtain polyamic acid solution B5 (molar ratio of CBDA/DABA/SQ-109 = 1.00/1.00/0.15).

[Comparative Example B6: Synthesis of polyamic acid solution B6]

While passing nitrogen through a reactor equipped with a nitrogen introduction pipe and stirring blade, 1,2,3,4-cyclobutanetetracarboxylic dianhydride (CBDA, 3.98 g) and 4,4'-diaminobenzanilide (DABA, 4.55 g) g) was added, dissolved in N,N-dimethylacetamide (DMAc, 76.0 g), and then stirred at 25°C for 24 hours. After that, SQ-109 (27.3 g) was added and stirred for 24 hours to obtain polyamic acid solution B6 (molar ratio of CBDA/DABA/SQ-109 = 1.00/1.00/0.50).

[Comparative Example C1: Synthesis of polyamic acid solution C1]

Pyromellitic dianhydride (PMDA, 6.54 g) and 4,4'-diamino-2,2'-bis(trifluoromethyl)biphenyl (TFMB) were passed through nitrogen through a reactor equipped with a nitrogen introduction tube and stirring blade. , 9.61 g) was added and dissolved in N,N-dimethylacetamide (DMAc, 164.0 g), and then stirred at 25°C for 24 hours to obtain polyamic acid solution C1 (molar ratio of PMDA/TFMB = 1.00/1.00).

[Comparative Example D1: Synthesis of polyamic acid solution D1]

Pyromellitic dianhydride (PMDA, 3.27 g) and 4,4'-diaminobenzanilide (DABA, 3.41 g) were added while passing nitrogen through a reactor equipped with a nitrogen introduction tube and stirring blade, and N,N-dimethylacetate was added. After dissolving in amide (DMAc, 63.0 g), polyamic acid solution D1 was obtained by stirring at 25°C for 24 hours (molar ratio of PMDA/DABA = 1.00/1.00).

The polyamic acid solutions obtained in the above examples and comparative examples were filmed by the following method, and optical properties, thermal properties, and mechanical properties were measured.

[Example 1]

Polyamic acid solution A was applied onto a polyester film (A4100, Toyobo product) using a casting applicator, and heated at 100°C for 18 minutes in a nitrogen atmosphere. The obtained green film was cut with a cutter, peeled off from the polyester film, and fixed to a metal frame. Thermal imidization was performed by sequentially heating to 200°C x 10 min, 250°C x 10 min, 300°C x 10 min, and 350°C x 10 min while gradually increasing the temperature at a rate of 10°C/min under a nitrogen atmosphere. After cooling, the polyimide film was obtained by removing it from the metal frame.

[Examples 2 to 5]

A polyimide film was obtained in the same manner as in Example 1, except that polyamic acid solution B, Ca∼Ce, D, and B2 were used instead of polyamic acid solution A. The ingredients used at that time and the evaluation results are shown in Table 1.

[Comparative Examples 1 to 9]

A polyimide film was obtained in the same manner as in Example 1, except that polyamic acid solutions A1, B1, B4, B5, B6, C1, and D1 were used instead of polyamic acid solution A. The ingredients used at that time and the evaluation results are shown in Table 1.

As shown in Table 1, the polyimide film (Examples 1, 2, 3a, 4) containing 1 mol% of SQ1 in the structure is the polyimide film (Comparative Example) containing the same composition except that it does not contain SQ1. Compared to 1, 2, 6, 9), it shows almost the same total light transmittance, haze, yellow index, Tg, and CTE, and also shows that the term product is increasing.

Comparing Example 2, Comparative Example 3, Comparative Example 4, and Comparative Example 5, when SQ-109, which does not have an acid anhydride group at the terminal, was mixed instead of SQ1, which has an acid anhydride group at the terminal, the addition amount was 1%, 15%, and 50%. As the percentage was increased, cloudiness of the polyamic acid solution and polyimide film was observed. Additionally, when SQ-109 was mixed, no increase in the field product was observed, and as the amount added, the film became weaker.

Comparing Examples 3a to 3e and Comparative Example 6, the term product of Examples 3a to 3e was improved compared to Comparative Example 6.

(Application example 1)

Example: A dispersion (“Snowtex (registered trademark) NMP-ST-ZL” manufactured by Nissan Chemical Industries, Ltd.) formed by dispersing colloidal silica in NMP as a lubricant in a solution of Ca was prepared so that the amount of colloidal silica (lubricant) was polyamic acid. It was added to make 0.3% by mass of the total amount of polymer solids in the solution, and stirred at room temperature for 24 hours. This was used as the example Ca2 solution.

Next, the Example Ca2 solution was applied using a comma coater on the non-lubricated surface of polyethylene terephthalate film A4100 (manufactured by Toyobo Co., Ltd.) so that the final film thickness was 1.5 ㎛, and then The Example Ca solution was applied on the Example Ca2 solution by a die coater so that the final film thickness was 22 μm. This was dried at 110°C for 10 minutes. The polyamic acid film that has achieved self-supporting properties after drying is peeled from the A4100 film as a support, passed through a pin tenter having a pin sheet on which pins are placed, and the ends of the film are held by inserting them into the pins to prevent the film from breaking. In addition, the pin sheet spacing was adjusted to prevent unnecessary sagging, and it was transported, heated at 200°C for 3 minutes, 250°C for 3 minutes, 300°C for 3 minutes, and 400°C for 3 minutes to proceed with the imidization reaction. . After that, it was cooled to room temperature for 2 minutes, and the parts with poor planarity at both ends of the film were cut out with a slitter and rolled up into a roll to obtain 500 m of polyimide film A1 with a width of 450 mm.

(Application example 2)

First, the polyimide film obtained in Example 3a (PMDA/TFMB/SQ1) was cut into a rectangle of 360 mm x 460 mm. Next, as a film surface treatment, UV/O _{3 was irradiated for 3 minutes using a UV/O 3 irradiator} (SKR1102N-03 manufactured by LAN Technical). At this time, the distance between the UV/O ₃ lamp and the film was set to 30 mm.

Spray 3-aminopropyltrimethoxysilane (KBM-903, manufactured by Shin-Etsu Chemical Co., Ltd.) as a silane coupling agent on display glass (370 mm × 470 mm, 0.7 mm thick glass substrate: OA10G manufactured by Nippon Denki Glass Co., Ltd.). Applied with a coater. In addition, the glass substrate was washed with pure water, dried, then irradiated with a UV/O ₃ irradiator (SKR1102N-03 manufactured by LAN Technical) for 1 minute and then dry cleaned.

Next, the glass substrate coated with the silane coupling agent was set on a roll laminator equipped with a silicone rubber roller, and first, 500 ml of pure water was dropped onto the surface coated with the silane coupling agent using a dropper so as to spread over the entire substrate to wet the substrate.

The surface-treated surface of the above-mentioned surface-treated polyimide film is overlapped to face the silane coupling agent-coated surface of the glass substrate, that is, the surface wetted with pure water, and a roll is sequentially rotated from one side of the glass substrate between the polyimide film and the glass substrate. The pure water was pressed while pushing out, and a glass substrate and a polyimide film were laminated to obtain a provisional laminate. The laminator used was a laminator with an effective roll width of 650 mm manufactured by MCK, and the bonding conditions were air source pressure: 0.5 MPa, laminating speed: 50 mm/sec, roll temperature: 22°C, environmental temperature 22°C, and humidity 55% RH. .

The obtained temporary laminated body was heat-treated at 200°C for 10 minutes in a clean oven to obtain a laminated body including a polyimide film and a glass substrate.

On the polyimide film side of the obtained laminate, a tungsten film (film thickness: 75 nm) was formed by the following process, and a silicon oxide film (film thickness: 150 nm) was further formed as an insulating film without contact with the atmosphere. Next, a silicon oxynitride film (film thickness: 100 nm) serving as an underlying insulating film was formed by plasma CVD, and an amorphous silicon film (film thickness: 54 nm) was further formed by laminating the film without contact with the atmosphere.

A TFT device was manufactured using the obtained amorphous silicon film. First, an amorphous silicon thin film is patterned to form a silicon region of a predetermined shape, followed by appropriate formation of a gate insulating film, formation of a gate electrode, formation of a source region or drain region by doping the active region, formation of an interlayer insulating film, Source and drain electrodes were formed and activation processing was performed to produce an array of P-channel TFTs.

The polyimide film is cut by heating it with a UV-YAG laser along the inside of about 0.5 mm of the outer circumference of the TFT array, and then peeled from the end of the cut area by using a thin razor-shaped blade to create a flexible A3-sized TFT. I got the array. Peeling was possible with extremely small force, and it could be done without damaging the TFT. Even when the obtained flexible TFT array was wound around a 5 mm phi round bar, no performance deterioration was observed and good characteristics were maintained.

After Example 11 and Comparative Example 11

Next, Example 11 and beyond and Comparative Example 11 and beyond will be described. Specifically, these will be explained regarding the synthesis of silsesquioxane compounds, synthesis of polyamic acid solutions, preparation of polyimide films, various evaluation results, etc.

[Obtainment of acid anhydride group-containing double decker-type silsesquioxane derivative 1 (hereinafter referred to as “AASQ1”)]

As the acid anhydride group-containing double decker-type silsesquioxane derivative 1 (i.e., AASQ1), DDSQ manufactured by Nippon Zairyogen Co., Ltd. was obtained. Here, DDSQ, or AASQ1, is a powder-type product.

[Synthesis of amino group-containing double decker-type silsesquioxane derivative 1 (hereinafter referred to as “AMSQ1”)]

Amino group-containing double-decker type silsesquioxane derivative 1 (i.e., AMSQ1) represented by the following structure was produced by the method described in Japanese Patent Application Laid-Open No. 2006-265243.

[Synthesis of acid anhydride group-containing double decker-type silsesquioxane derivative 2 (hereinafter referred to as “AASQ2”)]

0.535 g (0.500 mmol) of a compound in which all Z1 in the general formula AA-D2 is a hydrogen atom and all R1 is a phenyl group and THF (15 mL) were placed in a reaction vessel and stirred at room temperature to dissolve the compound. To this solution, 0.421 g (2.0 mmol) of trimellitic anhydride chloride was slowly added. A reaction solution was obtained by stirring this at room temperature for 3 hours. This reaction solution was concentrated under reduced pressure, and the residue was dried at 120°C under vacuum to remove unreacted trimellitic anhydride chloride. NMR and IR measurements confirmed that the desired reaction was progressing. Through this procedure, double decker-type silsesquioxane derivative 2 (i.e., AASQ2) containing an acid anhydride group was obtained.

[Synthesis of acid anhydride group-containing corner-open silsesquioxane derivative 3 (hereinafter referred to as “AASQ3”)]

In the general formula AA-C1, 0.466 g (0.500 mmol) of a compound in which all Z ¹ is a hydrogen atom and all R ¹ is a phenyl group (SO1458 manufactured by Hybrid Plastics) and THF (15 mL) are placed in a reaction vessel and incubated at room temperature. This compound was dissolved by stirring under low temperature. To this solution, 0.316 g (1.5 mmol) of trimellitic anhydride chloride was slowly added. A reaction solution was obtained by stirring this at room temperature for 3 hours. This reaction solution was concentrated under reduced pressure, and the residue was dried at 120°C under vacuum to remove unreacted trimellitic anhydride chloride. NMR and IR measurements confirmed that the desired reaction was progressing. Through this procedure, acid anhydride group-containing open-corner silsesquioxane derivative 3 (i.e., AASQ3) was obtained.

[Synthesis of polyamic acid solution A-1]

1,2,3,4-cyclobutanetetracarboxylic dianhydride (CBDA, 3.922 g) and 4,4'-diamino-2,2'- were passed through nitrogen through a reactor equipped with a nitrogen introduction pipe and stirring blade. Bis(trifluoromethyl)biphenyl (TFMB, 6.405 g) was added, dissolved in N,N-dimethylacetamide (DMAc, 80 ml), and then stirred at 25°C for 18 hours to prepare polyamic acid solution A-1. Obtained (molar ratio of CBDA/TFMB = 1.00/1.00). That is, polyamic acid solution A-1 was synthesized according to the formulation shown in Table 2.

[Synthesis of polyamic acid solution A-2]

1,2,3,4-cyclobutanetetracarboxylic dianhydride (CBDA, 1.961 g), 4,4'-diamino-2,2'- while passing nitrogen through a reactor equipped with a nitrogen introduction pipe and stirring blade. Bis(trifluoromethyl)biphenyl (TFMB, 3.268 g) and AASQ1 (0.303 g) were added, dissolved in γ-butyrolactone (γ BL, 32 ml), and stirred at 25°C for 18 hours to obtain polyamic acid. Solution A-2 was obtained (molar ratio of CBDA/AASQ1/TFMB=0.98/0.02/1.00). That is, polyamic acid solution A-2 was synthesized according to the formulation shown in Table 2.

[Synthesis of polyamic acid solution A-3]

Polyamic acid solution A-3 was prepared according to the formulation shown in Table 2 in the same procedure as the synthesis of polyamic acid solution A-2.

[Synthesis of polyamic acid solution B-1]

While passing nitrogen through a reactor equipped with a nitrogen introduction pipe and stirring blade, 1,2,3,4-cyclobutanetetracarboxylic dianhydride (CBDA, 7.844 g) and 4,4'-diaminobenzanilide (DABA, 8.954 g) g) was added and dissolved in N,N-dimethylacetamide (DMAc, 151 ml), and then stirred at 25°C for 24 hours to obtain polyamic acid solution B-1 (molar ratio of CBDA/DABA = 1.00/0.985). That is, polyamic acid solution B-1 was synthesized according to the formulation shown in Table 2. Additionally, 8.954 g of DABA is 98.5 mmol when converted to mole. Regarding this, in a preliminary experiment, the polyamic acid solution synthesized by injecting 100 mmol of DABA and 100 mmol of CBDA resulted in a high viscosity solution unsuitable for film formation, so when synthesizing polyamic acid solution B-1, DABA was used at 98.5%. It was taken as mmol.

[Synthesis of polyamic acid solution B-2]

1,2,3,4-cyclobutanetetracarboxylic dianhydride (CBDA, 2.942 g), 4,4'-diaminobenzanilide (DABA, 3.588 g) while passing nitrogen through a reactor equipped with a nitrogen introduction pipe and stirring blade. g) and AASQ1 (1.170 g) were added, dissolved in N,N-dimethylacetamide (DMAc, 53 ml), and then stirred at 25°C for 24 hours to obtain polyamic acid solution B-1 (CBDA/AASQ1/DABA) molar ratio = 0.95/0.05/1.00). That is, polyamic acid solution B-2 was synthesized according to the formulation shown in Table 2.

[Synthesis of polyamic acid solution C-1]

Pyromellitic dianhydride (PMDA, 4.362 g) and 4,4'-diamino-2,2'-bis(trifluoromethyl)biphenyl (TFMB) were passed through nitrogen through a reactor equipped with a nitrogen introduction pipe and stirring blade. , 6.405 g) was dissolved in N-methyl-2-pyrrolidone (NMP, 164 ml), and then stirred at 25°C for 24 hours to obtain polyamic acid solution C-1 (molar ratio of PMDA/TFMB = 1.00). /1.00). That is, polyamic acid solution C-1 was synthesized according to the formulation shown in Table 3.

[Synthesis of polyamic acid solution C-2]

Pyromellitic dianhydride (PMDA, 3.272 g) and 4,4'-diamino-2,2'-bis(trifluoromethyl)biphenyl (TFMB) were passed through nitrogen through a reactor equipped with a nitrogen introduction tube and stirring blade. , 4.902 g) and AASQ1 (0.454 g) were added and dissolved in N-methyl-2-pyrrolidone (NMP, 52 ml), and then stirred at 25°C for 24 hours to obtain polyamic acid solution C-2 (PMDA) /AASQ1/TFMB molar ratio=0.98/0.02/1.00). That is, polyamic acid solution C-2 was synthesized according to the formulation shown in Table 3.

[Synthesis of polyamic acid solution C-3]

Pyromellitic dianhydride (PMDA, 3.272 g) and 4,4'-diamino-2,2'-bis(trifluoromethyl)biphenyl (TFMB) were passed through nitrogen through a reactor equipped with a nitrogen introduction tube and stirring blade. , 4.708 g) and AMSQ1 (0.401 g) were added and dissolved in N-methyl-2-pyrrolidone (NMP, 67 ml), and then stirred at 25°C for 24 hours to obtain polyamic acid solution C-3 (PMDA) /AMSQ1/TFMB molar ratio=1.00/0.02/0.98). That is, polyamic acid solution C-3 was synthesized according to the formulation shown in Table 3.

[Synthesis of polyamic acid solution C-4]

Polyamic acid solution C-4 was synthesized according to the formulation shown in Table 3 in the same procedure as the synthesis of polyamic acid solution C-3.

[Synthesis of polyamic acid solution C-5]

Polyamic acid solution C-5 was synthesized according to the formulation shown in Table 3 in the same procedure as the synthesis of polyamic acid solution C-3.

[Synthesis of polyamic acid solution C-6]

Pyromellitic dianhydride (PMDA, 1.42 g) and 4,4'-diamino-2,2'-bis(trifluoromethyl)biphenyl (TFMB) were passed through nitrogen through a reactor equipped with a nitrogen introduction pipe and stirring blade. , 2.12 g) and AASQ2 (0.117 g) were added and dissolved in N-methyl-2-pyrrolidone (NMP, 30 g), and then stirred at 25°C for 24 hours to obtain polyamic acid solution C-6 (PMDA) /AASQ2/TFMB molar ratio=0.98/0.01/1.00). That is, polyamic acid solution C-6 was synthesized according to the formulation shown in Table 3.

[Synthesis of polyamic acid solution C-7]

Pyromellitic dianhydride (PMDA, 1.64 g) and 4,4'-diamino-2,2'-bis(trifluoromethyl)biphenyl (TFMB) were passed through nitrogen through a reactor equipped with a nitrogen introduction tube and stirring blade. , 2.45 g) and AASQ3 (0.196 g) were added and dissolved in N-methyl-2-pyrrolidone (NMP, 19 g), and then stirred at 25°C for 24 hours to obtain polyamic acid solution C-6 (PMDA) /AASQ3/TFMB molar ratio=0.98/0.02/1.00). That is, polyamic acid solution C-6 was synthesized according to the formulation shown in Table 3.

A polyimide film was produced using these polyamic acid solutions by the following method, and the optical properties, thermal properties, and mechanical properties of the polyimide film were measured.

[Comparative Example 11]

Polyamic acid solution A-1 was applied on a polyester film (A4100, Toyobo product) using a casting applicator, and the polyamic acid solution on the polyester film was applied under predetermined conditions (specifically, GF1 described later). heated. The green film obtained by this heating was cut with a cutter, peeled off from the polyester film, and fixed to a metal frame. Thermal imidization was performed by heating the green film fixed to the metal frame under predetermined conditions (specifically, B1 described later). After cooling, the polyimide film was obtained by removing it from the metal frame.

[Examples 11 to 19 and Comparative Examples 12 to 18]

Instead of polyamic acid solution A-1, the polyamic acid solution shown in Tables 2 to 3 was used, the polyamic acid solution was heated under the GF production conditions shown in Tables 2 to 3, and baking shown in Tables 2 to 3. A polyimide film was obtained in the same manner as in Example 1 except that the green film was heated under the following conditions.

[Example 20]

Polyamic acid solution C-2 was applied on a polyester film (A4100, Toyobo product) using a comma coater, and the polyamic acid solution on the polyester film was coated under predetermined conditions (specifically, GF3, described later). heated. The green film obtained by this heating was cut with a cutter, peeled off from the polyester film, and fixed to the frame from which the Xenomax (registered trademark) film (manufactured by Xenomax Japan) was cut out with Campton tape. Thermal imidization was performed by heating the green film fixed to the frame under predetermined conditions (specifically, B3 described later). After cooling, the polyimide film was obtained by removing it from the mold.

In these tables, GF1 and GF2 and GF3 are heating conditions for forming green films. GF1 indicates that the polyamic acid solution on the polyester film was heated at 100°C for 18 minutes under a nitrogen atmosphere. On the other hand, GF2 indicates that the polyamic acid solution on the polyester film was heated at 100°C for 20 minutes under a nitrogen atmosphere. GF3 indicates that the polyamic acid solution on the polyester film was heated at 120°C x 12 minutes in air.

B1 and B2 and B3 are the firing conditions of the green film. Green films can be thermally imidized in B1, B2, or B3. B1 indicates that the green film was heated sequentially at 200°C x 10 min, 250°C x 10 min, 300°C x 10 min, and 350°C x 10 min while gradually increasing the temperature at a rate of 10°C/min under a nitrogen atmosphere. On the other hand, B2 indicates that the green film was heated sequentially at 300°C x 60 minutes and 400°C x 30 minutes while gradually increasing the temperature at a rate of 10°C/min under a nitrogen atmosphere. B3 indicates that the green film was sequentially heated under air for 3 minutes in a furnace at 220°C, 3 minutes in a furnace at 270°C, 3 minutes in a furnace at 320°C, and 3 minutes in a furnace at 370°C.

In addition, in these tables, “-” in cells representing characteristics indicates unmeasured. In cells of characteristics for which measurement itself was impossible (for example, CTE in Comparative Example 17), “Measurement not possible” was written.

As shown in Table 2, in the blend system of CBDA and TFMB, a polyimide film containing 2 mol% AASQ1 in the structure (Example 11) or a polyimide film containing 5 mol% AASQ1 (Example 12), compared to the polyimide film not containing AASQ1 (Comparative Example 11), shows almost the same total light transmittance, haze, yellow index, Rth, Td ₁ (i.e., thermal decomposition temperature), Tg, and CTE, and is excellent in terms of field product. did. Among these properties, regarding CTE, the polyimide film (Example 11) containing 2 mol% AASQ1 in the structure and the polyimide film (Example 12) containing 5 mol% AASQ1 contained AASQ1. Compared to the polyimide film without (Comparative Example 11), there was a tendency for CTE to increase, but the degree of increase in CTE was at an acceptable level (under these circumstances, in this study, haze was also said to be “almost equal”) It is expressed. Hereinafter, the same applies.).

Even in the blended system of CBDA and DABA, the polyimide film (Example 13) containing 5 mol% of AASQ1 in the structure had an almost equal total light transmittance compared to the polyimide film (Comparative Example 12) not containing AASQ1. , haze, yellow index, Rth, Td ₁ (i.e., thermal decomposition temperature), Tg, and CTE, and the term product was excellent.

As shown in Table 3, even in the mixture system of PMDA and TFMB, the polyimide film (Example 14) containing 2 mol% of AASQ1 in the structure is similar to the polyimide film (Comparative Example 13) that does not contain AASQ1. In comparison, the total light transmittance, haze, yellow index, Rth, Td ₁ (i.e., thermal decomposition temperature), Tg, and CTE were almost equivalent, and the term product was excellent.

When the firing conditions of the polyimide film are more stringent than those of B1, specifically, in the case of B2, which is set after assuming that the polyimide film may be exposed to an even higher temperature environment during the production process of the TFT array, 2 moles are used in the structure. The polyimide film containing % AASQ1 (Example 15) was inferior in yellow index to the polyimide film not containing AASQ1 (Comparative Example 14), but had almost equivalent total light transmittance, haze, Rth, Tg, It showed CTE and the term product was excellent. Incidentally, when the firing conditions of the polyimide film are BF3, which is slightly more stringent than B1, the polyimide film containing 2 mol% of AASQ1 in the structure (Example 20) is similar to the polyimide film containing no AASQ1 (Comparative Compared to example 14), it showed almost the same yellow index.

Regardless of whether the firing conditions are B1 or B2, the polyimide film containing 2 mol% of AMSQ1 in the structure (Examples 16 and 17) has almost The field product was excellent, showing equivalent total light transmittance, haze, yellow index, Rth, Tg, and CTE. Regarding Example 17 and Comparative Example 14, in which the firing conditions were common to B2, AMSQ1 was less likely to thermally decompose compared to AASQ1, and as a result, in the polyimide film containing 2 mol% of AMSQ1 in the structure (Example 17), Compared to the polyimide film (Example 15) containing 2 mol% of AASQ1 in the structure, it is believed that the increase in yellow index (i.e., deterioration of yellow index) due to thermal decomposition was suppressed.

On the other hand, the polyimide film containing 10 mol% of AMSQ1 in the structure (Comparative Examples 15 and 16) has a lower elongation at break and a lower tensile length product than the polyimide film (Comparative Examples 13 and 14) which does not contain AMSQ1. fell behind Incidentally, in Comparative Examples 17 and 18, the CTE could not be measured because the membrane was weak and broke during measurement.

In addition, like AASQ1 or AMSQ1, the field product was able to be improved in AASQ2 or AASQ3 while maintaining total light transmittance, haze, yellow index, Rth, Td ₁ (i.e., thermal decomposition temperature), Tg, and CTE. Specifically, the polyimide film (Example 18) containing approximately 1 mol% of AASQ2 in the structure has almost the same total light transmittance, haze, yellow index, and The term product was excellent, showing Rth, Td ₁ (i.e., thermal decomposition temperature), Tg, and CTE. The polyimide film containing 2 mol% of AASQ3 in the structure (Example 19) had almost equivalent total light transmittance, haze, yellow index, Rth, and Td compared to the polyimide film not containing AASQ3 (Comparative Example 14). The term product was excellent, showing ₁ (i.e. pyrolysis temperature), Tg, and CTE.

As described above, it was revealed that the polyimide film of the present invention has good mechanical properties while maintaining optical properties and thermal properties at the same level as compared to the case that does not contain a silsesquioxane compound. The polyimide film of the present invention has excellent optical properties, colorless transparency, excellent mechanical properties, and a relatively low CTE. Therefore, the polyimide film is bonded to a rigid inorganic substrate on a flat surface such as glass, and then formed into a film. By performing various electronic device processing and finally peeling from the inorganic substrate, a flexible electronic device can be produced.

Claims (11)

Polyamic acid, which is a copolymerization product of at least carboxylic acids, diamines, and silsesquioxane derivatives,
The silsesquioxane derivative has two or more dicarboxylic anhydride groups or two or more amino groups,
When the silsesquioxane derivative has two or more dicarboxylic acid anhydride groups, the number of moles of structural units derived from the silsesquioxane derivative (provided that the silsesquioxane derivative has more than two dicarboxylic acid anhydride groups) When having an acid anhydride group, this number of moles is the total number of moles of the silsesquioxane derivative divided by the total number of dicarboxylic acid anhydride groups of the silsesquioxane derivative and doubled) is the number of moles of the silsesquioxane derivative. It is 0.0001 times or more and 0.09 times or less relative to the sum of the number of moles of structural units derived from the derivative and the number of moles of structural units derived from the above carboxylic acids,
When the silsesquioxane derivative has more than two amino groups, the number of moles of structural units derived from the silsesquioxane derivative (however, when the silsesquioxane derivative has more than two amino groups, this number of moles is is the total number of moles of the silsesquioxane derivative divided by the total number of amino groups of the silsesquioxane derivative and doubled) is the number of moles of structural units derived from the silsesquioxane derivative and the diamines A polyamic acid that is 0.0001 times to 0.09 times the total number of moles of structural units from which it is derived. The polyamic acid according to claim 1, wherein the silsesquioxane derivative has at least two dicarboxylic anhydride groups. The polyamic acid according to claim 1, wherein the silsesquioxane derivative has at least two amino groups. According to paragraph 3,
Each of the amino groups has a linking group that connects the amino group to Si that is closest in bond to the amino group among the Si constituting the silsesquioxane derivative,
A polyamic acid in which each of the linking groups independently has a substituted or unsubstituted aromatic ring bonded to the amino group. The polyamic acid according to any one of claims 1 to 4, wherein the polyamic acid does not have a structural unit derived from 3,3',4,4'-biphenyltetracarboxylic dianhydride. A polyamic acid composition comprising the polyamic acid according to any one of claims 1 to 5 and a solvent. A polyimide obtained by imidizing the polyamic acid according to any one of claims 1 to 5. A polyimide film comprising the polyimide according to claim 7. A laminate comprising the polyimide film according to claim 8 and an inorganic substrate. A process of forming an electronic device on the polyimide film surface of the laminate according to claim 9,
A method of manufacturing a flexible electronic device, comprising the step of peeling off the inorganic substrate. A flexible electronic device comprising the polyimide film according to claim 8 and an electronic device formed on the polyimide film.

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