JPWO2010047346A6 - Underlayer film for image formation - Google Patents

Abstract

A lower layer film for image formation comprising a polyimide precursor having a repeating structure represented by the following formula (1) or a polyimide obtained by dehydrating and ring-closing the polyimide precursor. In the formula, A represents a tetravalent organic group, and B represents a divalent organic group represented by the following formula (2) or (3).

Description

  The present invention relates to a lower layer film for image formation, and further relates to an organic transistor fabricated using the lower layer film for image formation.

  Currently, in the manufacturing process of electronic devices, mask vapor deposition or photolithography etching is mainly used for pattern formation of electrodes and functional thin films. In these conventional methods, problems such as difficulty in increasing the size of the substrate and complicated processes have been pointed out.

  In recent years, it has been proposed to apply a coating technique using the difference in wettability of liquids to the patterning of functional thin films. This is because a patterning layer is formed on the substrate surface, which consists of areas that are easily wetted by liquid and areas that are not easily wetted by liquid, and then a functional thin film forming material solution is applied and dried on this patterning layer. In this method, a functional thin film is formed only in an easy region, and an electronic device such as an organic EL (electroluminescence) element or an organic FET (field effect transistor) element is manufactured.

  As a patterning layer for such a functional thin film, a photocatalyst containing layer made of titanium dioxide and organopolysiloxane is irradiated with ultraviolet light through a mask (see, for example, Patent Document 1), and has a light absorption site such as a dye. Known is a layer formed of a compound and a fluoropolymer, which is irradiated with ultraviolet light through laser irradiation or a mask (see, for example, Patent Document 2). In addition, a method has been proposed in which a fluorine-based coating agent is deposited through a mask to form the patterning layer (see, for example, Patent Document 3).

  The patterning layer proposed so far, such as the above-mentioned patent document, remains in the element even after finishing the role of patterning the functional thin film. Therefore, this patterning layer is required to have durability against subsequent processes and reliability that does not adversely affect the characteristics even in the electronic device. Such required characteristics of the patterning layer vary depending on the device to be manufactured and the use location of the patterning layer. Among them, electrical insulation is an important required characteristic for the patterning layer of the electrode.

  In addition, the methods proposed so far focus only on the characteristics of the patterning layer. Therefore, for example, when patterning the source electrode and the drain electrode of the organic FET element, it is necessary to separately prepare a gate insulating film under the patterning layer.

On the other hand, polyimide is excellent in heat resistance, mechanical strength, electrical insulation, chemical resistance, and the like, and is used in various electronic devices. As an example of using polyimide as a patterning layer, one using a tetracarboxylic acid anhydride having an alicyclic structure (for example, see Patent Document 4) is disclosed. However, in these examples, since the amount of ultraviolet irradiation is extremely large, a long exposure process has been unavoidable.
JP 2000-223270 A JP 2004-146478 A JP 2004-238551 A JP 2006-185898 A

  The present invention has been made in view of such circumstances, and can easily change the hydrophilicity / hydrophobicity of the film surface of the formed lower layer film for image formation even with a small amount of ultraviolet irradiation. It is to provide an underlayer film for formation.

As a result of intensive studies to achieve the above object, the present inventors have included a thiol ester structure in the polyimide precursor or the side chain of the polyimide obtained from the polyimide precursor. On the surface of the cured film obtained from the body and polyimide, the water contact angle was found to change greatly with a small exposure amount, and the present invention was completed.
That is, as a first aspect of the present invention, a lower layer for image formation comprising a polyimide precursor having a repeating structure represented by the following formula (1) or a polyimide obtained by dehydrating and ring-closing the polyimide precursor: Relates to the membrane.

(In the formula, A represents a tetravalent organic group, B represents a divalent structure represented by the following formula (2) or (3), and R ¹ and R ² are each independently a hydrogen atom or Represents a monovalent organic group, and n represents a natural number.)

(In the formula, X represents a single bond or a divalent aromatic group having 6 to 20 carbon atoms; Y represents a single bond, —O—, —COO—, —OCO—, —CONH—, —CH ₂ O; _-, - CH 2 COO- or _-CH 2 _CH 2 COO- represents, Z is an aliphatic hydrocarbon group which may carbon atoms 3 to 26 may be substituted with a fluorine atom, R represents each independently And represents a fluorine atom, an alkoxy group having 1 to 3 carbon atoms or an alkyl group having 1 to 3 carbon atoms, and t represents an integer of 0 to 3.)
As a 2nd viewpoint, it is obtained by making the tetracarboxylic dianhydride component containing the tetracarboxylic dianhydride represented by following formula (6) react with the diamine component containing the diamine represented by Formula (7). The present invention relates to a lower layer film for image formation comprising a polyimide precursor or a polyimide obtained by dehydrating and ring-closing the polyimide precursor.

[In the formula, A represents a tetravalent organic group, and B represents the formula (2) or the formula (3).

(In the formula, X represents a single bond or a divalent aromatic group having 6 to 20 carbon atoms; Y represents a single bond, —O—, —COO—, —OCO—, —CONH—, —CH ₂ O; _-, - CH 2 COO- or _-CH 2 _CH 2 COO- represents, Z is an aliphatic hydrocarbon group which may carbon atoms 3 to 26 may be substituted with a fluorine atom, R represents each independently Represents a fluorine atom, an alkoxy group having 1 to 3 carbon atoms or an alkyl group having 1 to 3 carbon atoms, and t represents an integer of 0 to 3). ]

  As a third aspect, Z in formula (2) or formula (3) represents an aliphatic hydrocarbon group having 3 to 26 carbon atoms in which an arbitrary hydrogen atom is substituted with a fluorine atom. The underlayer film for image formation described in 2.

  As a fourth aspect, the present invention relates to the underlayer film for image formation according to the first to third aspects, wherein A represents a tetravalent organic group having an aliphatic ring or consisting only of an aliphatic group.

  As a fifth aspect, the present invention relates to the underlayer film for image formation according to any one of the first aspect to the fourth aspect, in which B represents a divalent structure represented by the formula (2).

  As a sixth aspect, the present invention relates to the lower film for image formation according to any one of the first to fifth aspects, in which X and Y represent a single bond.

  As a seventh aspect, the present invention relates to an organic transistor having the image forming lower layer film according to any one of the first aspect to the sixth aspect.

  As an eighth aspect, the present invention relates to a diamine compound represented by the following formula (14) or the following formula (15).

(In the formula, X represents a single bond or a divalent aromatic group having 6 to 20 carbon atoms; Y represents a single bond, —O—, —COO—, —OCO—, —CONH—, —CH ₂ O; _-, - CH 2 COO- or _-CH 2 _CH 2 COO- represents, Z is an aliphatic hydrocarbon group having a carbon number of 3 to 26 arbitrary hydrogen atoms are substituted by fluorine atoms, R represents each Independently represents a fluorine atom, an alkoxy group having 1 to 3 carbon atoms or an alkyl group having 1 to 3 carbon atoms, and t represents an integer of 0 to 3).

  As a 9th viewpoint, it is related with the polyimide obtained by spin-dry | dehydrating and ring-closing the polyimide precursor containing the repeating unit represented by following formula (1), or this polyimide precursor.

(In the formula, A represents a tetravalent organic group, B represents a divalent structure represented by the following formula (2a) or (3a), and R ¹ and R ² each independently represents a hydrogen atom or Represents a monovalent organic group, and n represents a natural number.)

(In the formula, X represents a single bond or a divalent aromatic group having 6 to 20 carbon atoms; Y represents a single bond, —O—, —COO—, —OCO—, —CONH—, —CH ₂ O; _-, - CH 2 COO- or _-CH 2 _CH 2 COO- represents, Z is an aliphatic hydrocarbon group having a carbon number of 3 to 26 arbitrary hydrogen atoms are substituted by fluorine atoms, R represents each Independently represents a fluorine atom, an alkoxy group having 1 to 3 carbon atoms or an alkyl group having 1 to 3 carbon atoms, and t represents an integer of 0 to 3).

  As a tenth aspect, it is obtained by reacting a tetracarboxylic dianhydride component containing a tetracarboxylic dianhydride represented by the following formula (6) with a diamine component containing a diamine represented by the formula (7). The present invention relates to an image-forming underlayer film coating solution comprising a polyimide precursor or a polyimide obtained by dehydrating and ring-closing the polyimide precursor.

(In the formula, A represents a tetravalent organic group, and B represents Formula (2) or Formula (3).
Wherein R ¹ and R ² each independently represent a hydrogen atom or a monovalent organic group, and X is a single bond or a divalent aromatic group having 6 to 20 carbon atoms. the stands, Y is a single bond, -O -, - COO -, - OCO -, - CONH -, - CH 2 O -, - CH 2 COO- or _-CH 2 _CH 2 COO- represents, Z is fluorine atom Represents an aliphatic hydrocarbon having 3 to 26 carbon atoms which may be substituted with, R independently represents a fluorine atom, an alkoxy group having 1 to 3 carbon atoms or an alkyl group having 1 to 3 carbon atoms; t represents an integer of 0 to 3. )

  11. The eleventh aspect according to claim 10, wherein Z in the formula (2) or the formula (3) represents an aliphatic hydrocarbon group having 3 to 26 carbon atoms in which an arbitrary hydrogen atom is substituted with a fluorine atom. The present invention relates to an image-forming underlayer coating solution.

  As a twelfth aspect, the present invention relates to the image-forming underlayer coating solution according to claim 10 or 11, further comprising a soluble polyimide having an imidization rate of 80% or more.

  As a thirteenth aspect, the present invention relates to an image forming lower layer film obtained by baking the image forming lower layer coating solution according to claim 10.

  As a fourteenth aspect, the present invention relates to an organic transistor having a film obtained by baking the image-forming underlayer film coating solution according to any one of claims 10 to 13.

  The underlayer film for image formation of the present invention can change the surface of the film from hydrophobic to hydrophilic with a small amount of UV irradiation, and therefore, by using these characteristics, image formation of functional materials such as electrodes can be performed. Is possible. Therefore, it is possible to greatly shorten the process time in the manufacture of electronic devices, and it becomes a very effective material in terms of productivity.

The present invention is a novel image-forming underlayer film containing a polyimide precursor having a thiol ester bond in the side chain or a polyimide obtained from the polyimide precursor. Further, the present invention relates to an organic transistor using the image forming film.
Details will be described below.

[Polyimide Precursor] The present invention is a lower layer film for image formation comprising a polyimide precursor having a repeating structure represented by the following formula (1) or a polyimide obtained by dehydrating and ring-closing the polyimide precursor. is there.

(In the formula, A represents a tetravalent organic group, B represents a divalent structure represented by Formula (2) or Formula (3), and R ¹ and R ² each independently represent a hydrogen atom or Represents a monovalent organic group, and n represents a natural number.)

In the above formula (1), R ¹ and R ² each represent a hydrogen atom or a monovalent organic group, and specific examples of the monovalent organic group include, for example, an alkyl group having 1 to 4 carbon atoms.
Examples of the alkyl group having 1 to 4 carbon atoms include methyl group, ethyl group, propyl group, isopropyl group, butyl group, isobutyl group, and t-butyl group.
Among these, it is preferable that R ¹ and R ² are hydrogen atoms.

In the above formula (1), the structure of the organic group represented by A is not particularly limited as long as it is a tetravalent organic group. Moreover, the polyimide precursor may have a structure represented by 1 type or multiple types of Formula (1). Therefore, in the polyimide precursor, the structure of the organic group represented by A may be one type or a plurality of types may be mixed. Especially, it is preferable that A is a tetravalent organic group which has an aliphatic ring or consists only of an aliphatic. More preferably, it is a tetravalent organic group having an aliphatic ring.
Preferable specific examples of the organic group represented by A include organic groups of the following formulas A-1 to A-46.

The above formulas A-1 to A-46 can be appropriately selected depending on required characteristics when an image forming lower layer film is used.
For example, among the above formulas A-1 to A-46, exposure sensitivity (in this specification, exposure sensitivity represents the degree of conversion from hydrophobicity to hydrophilicity per exposure amount (ultraviolet irradiation amount)) is improved. Examples of the tetravalent organic group include tetravalent organic groups having an aliphatic ring represented by Formulas A-1 to A-25 or consisting only of an aliphatic group. Particularly effective organic groups include A-1 , A-6, A-16 or A-19.
Moreover, the tetravalent organic group of Formula A-1 thru | or A-25 is preferable also from a viewpoint with the effect which improves insulation.
In the formula (1), in the organic group represented by A, when a group other than the formulas A-1 to A-25 is mixed, the ratio of the formulas A-1 to A-25 is 10 mol% or more. Preferably, 50 mol% or more is more preferable, and 80 mol% or more is most preferable.

In the above formula (1), B represents a divalent structure having a thiol ester bond in the side chain, as represented by the following formula (2) or formula (3).
When the thiol ester group is photodegraded by incorporating a thiol bond in the side chain of the polyimide precursor (or polyimide obtained therefrom) containing the repeating structure represented by the formula (1), the thiol ester group is introduced via the thiol ester group. The bonded side chain will be cleaved from the polymer main chain. Therefore, by adjusting the hydrophilicity / hydrophobicity of the side chain bonded through a thiol bond, it can be expected that the irradiation with light such as ultraviolet rays leads to a change in hydrophilicity / hydrophobicity.

In the above formula (2) or (3), X represents a single bond or a divalent aromatic group having 6 to 20 carbon atoms.
Y is a single bond, -O -, - COO -, - OCO -, - CONH -, - CH 2 O -, - CH 2 COO- or an _-CH 2 _CH 2 COO-.
Z represents an aliphatic hydrocarbon group having 3 to 26 carbon atoms, and any hydrogen atom may be substituted with a fluorine atom.
R independently represents a fluorine atom, an alkoxy group having 1 to 3 carbon atoms, or an alkyl group having 1 to 3 carbon atoms, and t represents an integer of 0 to 3.

The structure of B represented by the above formula (2) or (3) may contain an aromatic carbocycle in the side chain structure from the viewpoint of improving the absorption efficiency of ultraviolet rays.
Therefore, in the above formula (2) or (3), when X represents a divalent aromatic group having 6 to 20 carbon atoms, preferred aromatic groups are phenylene group, biphenylene group, terphenylene group, naphthylene. Group, anthracenylene group and the like.

Examples of the aliphatic hydrocarbon group having 3 to 26 carbon atoms in Z include propyl, isopropyl, butyl, isobutyl, t-butyl, pentyl, hexyl, octyl, 2-ethylhexyl, nonyl, sec-nonyl, isononyl, Alicyclic hydrocarbon having linear or branched alkyl groups such as decyl, dodecyl, tetradecyl, hexadecyl, octadecyl; alkenyl groups such as allyl, hexenyl; cyclobutane, cyclopentane, cyclohexane, cyclodecane, steroid skeleton, adamantane, etc. Groups: ethyl formate, methyl acetate, ethyl acetate, methyl propionate, diacetyl, methyl isobutyrate, ethyl isobutyrate, ethyl butyrate, propyl butyrate, isobutyl acetate, isobutyl isobutyl Rate, isobutyl butyrate, isobutyl isovalerate, isoamyl acetate, isoamyl propionate, amyl propionate, amyl isobutyrate, amyl butyrate, amyl isovalerate, allyl hexanoate, ethyl acetoacetate, ethyl heptyl Examples thereof include ester groups of rate, heptyl acetate, ethyl octylate, styrylyl acetate, nonyl acetate, boronyl acetate, and diethyl phthalate, and linear alkyl groups having 12 to 26 carbon atoms are particularly preferable.
In the above aliphatic hydrocarbon group, any hydrogen atom may be substituted with a fluorine atom, and preferably an aliphatic hydrocarbon having 3 to 26 carbon atoms in which any hydrogen atom is substituted with a fluorine atom Group, particularly preferably a linear fluoroalkyl group having 4 to 7 carbon atoms.

  Preferred specific examples of the structure of B represented by the above formula (2) or (3) include the structures shown in the following [B-1] to [B-17]. Among these divalent structures, the divalent structures represented by [B-13] to [B-17] are particularly preferable from the viewpoint of facilitating the improvement of hydrophobicity, and more preferably [B-15]. Thru | or the bivalent structure shown by [B-17].

  In addition, when other characteristics such as insulation, solvent solubility, film formability, and film adhesion are also considered as important characteristics, a polyimide precursor used for the image-forming underlayer film of the present invention ( In addition to the structure represented by the formula (1), the divalent organic group B in the formula (1) is a divalent organic compound having no thiol ester bond in the side chain. It may be a polyimide precursor (and a polyimide obtained therefrom) containing a structure represented by the following formula (4) replaced by the group D.

  In this case, the structure represented by the above formula (1) containing a divalent organic group B having a thiol ester bond in the side chain, and other divalent organic groups not having a thiol ester bond in the side chain The coupling | bonding with the structure of Formula (4) to perform may be any of a block coupling | bonding and / or a random coupling | bonding.

In the formula, A, R ¹ and R ² have the same definitions as in the above formula (1), m represents a natural number, and D represents another divalent structure having no thiol ester bond in the side chain.

In the polyimide precursor (and polyimide obtained therefrom) used for the image-forming underlayer film of the present invention, when D has a long-chain alkyl group in the side chain, it is represented by formula (4). If the content ratio of the structure (structure having no thiol ester bond in the side chain) is too high, the sensitivity to ultraviolet rays decreases. Therefore, when the structure represented by the formula (4) is included, the ratio of the structure represented by the formula (1) (a structure having a thiol ester bond in the side chain) is preferably 30 mol% or more.
Further, in order to further increase the exposure sensitivity and shorten the ultraviolet irradiation time, it is necessary to further increase the content ratio of the structure represented by the formula (1). In this case, the content ratio is 50 mol% or more. preferable.

In the formula (4), when D does not have a long-chain alkyl group in the side chain, the hydrophobicity of the film is mainly affected by the proportion of the structure represented by the formula (1). The ratio of the structure represented by the formula (1) may be determined in consideration of the surface tension of the material and the adhesion to the upper layer member.
In the structure represented by the above formula (2) or formula (3), when a part of the aliphatic hydrocarbon group of Z is substituted with a fluorine atom, the proportion of the structure represented by the formula (1) Even if it is 10 mol% or less, high hydrophobicity and sensitivity can be obtained. That is, it is considered that the change in hydrophilicity / hydrophobicity of the film is caused by decomposition / separation of the side chain structure, and even when the ratio of the formula (1) is 10 mol% or less, the exposure sensitivity does not necessarily decrease. .

  In the above formula (4), the other divalent structure D having no thiol ester bond is preferably one having a highly insulating structure. Specific examples include the following [D-1] to [D] D-57].

Of the following [D-1] to [D-57], the structures [D-1] to [D-5] are preferable from the viewpoint of easy improvement of insulation.
Moreover, as a structure with a high effect of improving solvent solubility, [D-2], [D-5], [D-7], [D-8], [D-12], [D-22], [D-24] thru | or [D-27], [D-29] are mentioned.
Specific examples of the hydrophobic structure having a long-chain alkyl group in the side chain can include the structures [D-55] to [D-57]. Improvement can be expected, and it can be used in a range where the sensitivity does not decrease.

  The aforementioned polyimide precursor is produced, for example, by polymerizing tetracarboxylic dianhydride and its derivative and diamine. In particular, a polyimide precursor (polyamide acid) represented by the following formula (5) is preferable because it can be obtained relatively easily by reacting a tetracarboxylic acid anhydride component and a diamine component as raw materials.

(In the formula, A, B and n have the same definitions as in formula (1).)

<Tetracarboxylic dianhydride and its derivative>
In the present invention, the tetracarboxylic dianhydride and its derivative are not particularly limited, but it is preferable to use a tetracarboxylic dianhydride represented by the following formula (6). A in the formula is synonymous with the definition of the above formula (1), and specific examples thereof include those shown in the above formulas A-1 to A-46.

(In the formula, A has the same definition as in formula (1).)

As described above, in the polyimide precursor, the structure of the organic group represented by A may be one type or a plurality of types may be mixed. Especially, it is preferable that A is a tetravalent organic group which has an aliphatic ring or consists only of an aliphatic, More preferably, it is a tetravalent organic group which has an aliphatic ring. Therefore, it is preferable that the tetracarboxylic dianhydride component contains a large amount of the compound of the formula (6), which is a tetravalent organic group in which A has an aliphatic ring or consists only of an aliphatic group. More preferably, it is preferable that A contains a large amount of the compound of the formula (6), which is a tetravalent organic group that is a tetravalent organic group having an aliphatic ring.
This is because, when a polyimide precursor or the like is produced using only an aromatic dianhydride and used as an image-forming underlayer film, the insulation tends to be remarkably lowered when a high electric field is applied to the image-forming underlayer film. is there. On the contrary, when an aliphatic acid dianhydride is used, the insulation in a high electric field is excellent.
For example, the operating voltage of the organic transistor may be about 1 MV / cm. In the case of the use, it is desirable to use aliphatic dianhydride as a raw material for the polyimide precursor, particularly from the viewpoint of insulation.

<Diamine>
In the present invention, the diamine used for the diamine component is represented by the following formula (7), and B is a structure represented by the following formula (2) or the following formula (3), that is, a divalent having a thiol ester bond in the side chain. This is the structure. Specific examples of B include the structures shown in the above [B-1] to [B-17].

(In the formula, X represents a single bond or a divalent aromatic group having 6 to 20 carbon atoms; Y represents a single bond, —O—, —COO—, —OCO—, —CONH—, —CH ₂ O; _-, - CH 2 COO- or _-CH 2 _CH 2 COO- represents, Z is an aliphatic hydrocarbon group which may carbon atoms 3 to 26 may be substituted with a fluorine atom, R represents independently a fluorine atom Represents an alkoxy group having 1 to 3 carbon atoms or an alkyl group having 1 to 3 carbon atoms, and t represents an integer of 0 to 3.)

  In addition to the diamine represented by the formula (7), a diamine other than the formula (7) represented by the formula (Q1) can be used in combination as long as the effects of the present invention are exhibited.

  In formula (Q1), D has the same definition as in formula (4) above. Therefore, specific examples of the diamine represented by the formula (Q1) include diamines having a divalent structure in which the structure of D is represented by [D-1] to [D-57] described above.

[Synthesis Method of Diamine Compound]
Of the diamines represented by the above formula (7), the method for obtaining a diamine in which B is the structure of the formula (2) is not particularly limited. As an example, it can be obtained by synthesizing a corresponding dinitro compound represented by the following general formula (8), reducing the nitro group and converting it to an amino group. The method for reducing the dinitro compound is not particularly limited, and usually palladium-carbon, platinum oxide, Raney nickel, iron, tin chloride, platinum black, rhodium-alumina, etc. are used as a catalyst, ethyl acetate, toluene, tetrahydrofuran, dioxane. And a reaction using a solvent such as an alcohol, hydrogen gas, hydrazine, hydrogen chloride, ammonium chloride and the like. As in the present invention, a compound having a sulfur atom or the like in the skeleton of a dinitro compound sometimes becomes a catalyst poison and may deactivate the catalyst. Therefore, a chemical reduction method using Raney nickel, iron, tin chloride, etc. Is more preferable.

(In the formula, X, Y, Z, R and t have the same definitions as in the above formula (2)).

  The dinitro compound of the above formula (8) can be obtained by reaction of dinitobenzoyl chloride (9) and thiol group-containing compound (10) shown below.

(In the formula, X, Y, Z, R and t have the same definitions as in formula (2)).

  Of the diamines represented by the above formula (7), the method for obtaining a diamine in which B is the structure of the formula (3) is not particularly limited. For example, it can be obtained by synthesizing a corresponding dinitro compound represented by the following formula (11) and then reducing the nitro group and converting it to an amino group in the same manner as in the case of the dinitro compound (8).

(In the formula, X, Y, Z, R and t have the same definitions as in formula (3).)

  The dinitro compound of the above formula (11) is obtained by reacting the thiol group-containing dinitro compound (12) shown below with an acid chloride (13) having an aliphatic hydrocarbon which may contain a fluorine atom. Can do.

(In the formula, X, Y, Z, R and t have the same definitions as in formula (3)).

<< Method for producing polyimide precursor >>
In order to obtain a polyimide precursor having a repeating structure represented by the formula (1), a tetracarboxylic dianhydride component including the tetracarboxylic dianhydride represented by the above formula (6) and the above formula (7) And a diamine component containing the diamine component represented by the above formula (Q1), if desired, are mixed in an organic solvent and reacted.

As a method of mixing the tetracarboxylic dianhydride component and the diamine component in an organic solvent, a solution in which the diamine component is dispersed or dissolved in the organic solvent is stirred, and the tetracarboxylic dianhydride component is used as it is or in an organic solvent. A method of adding by dispersing or dissolving in a solvent, a method of adding a diamine component to a solution in which a tetracarboxylic dianhydride component is dispersed or dissolved in an organic solvent, and a tetracarboxylic dianhydride component and a diamine component alternately. And the like.
Further, in the case of a compound having a plurality of tetracarboxylic dianhydride components and diamine components, the polymerization reaction may be performed in a state where these plural components are mixed in advance, or the polymerization reaction may be performed individually and sequentially.

  When polymerizing the polyimide precursor used in the present invention, the mixing ratio of the tetracarboxylic dianhydride component and the diamine component, that is, <total number of moles of tetracarboxylic dianhydride component>: <total number of moles of diamine component > Is preferably 1: 0.5 to 1: 1.5. Similar to the normal polycondensation reaction, the closer the molar ratio is to 1: 1, the higher the degree of polymerization of the polyimide precursor produced, and the higher the molecular weight.

In the method for producing the polyimide precursor, the temperature at which the tetracarboxylic dianhydride component and the diamine component are reacted in an organic solvent is usually −20 to 150 ° C., preferably 0 to 80 ° C.
If the reaction temperature is set to a high temperature, the polymerization reaction proceeds rapidly and is completed, but if it is too high, a high molecular weight polyimide precursor may not be obtained.

  In the polymerization reaction performed in an organic solvent, the solid content concentration of both components (the total mass of the tetracarboxylic acid anhydride component and the diamine component) in the solvent is not particularly limited, but if the concentration is too low, a high molecular weight polyimide precursor is used. It becomes difficult to obtain a body, and when the concentration is too high, the viscosity of the reaction solution becomes too high and uniform stirring becomes difficult, so 1 to 50% by mass, more preferably 5 to 30% by mass. The initial stage of the polymerization reaction is carried out at a high concentration, and it is possible to add an organic solvent after the purification of the polymer (polyimide precursor).

  The organic solvent used in the polymerization reaction is not particularly limited as long as the produced polyimide precursor can be dissolved, but N, N-dimethylformamide, N, N-dimethylformacetamide can be specifically exemplified. , N-methyl-2-pyrrolidone, N-methylcaprolactam, dimethyl sulfoxide, tetramethyl urea, pyridine, dimethyl sulfone, hexamethyl sulfoxide, γ-butyrolactone, and the like. These may be used alone or in admixture of two or more. Furthermore, even if it is a solvent which does not dissolve a polyimide precursor, you may mix with the said solvent in the range which the produced | generated polyimide precursor does not precipitate.

  The solution containing the polyimide precursor thus obtained can be used as it is for the preparation of an image-forming underlayer film coating solution described later. Further, the polyimide precursor can be precipitated and isolated in a poor solvent such as water, methanol, ethanol, etc. and recovered for use.

[Polyimide]
The polyimide precursor having the structure represented by the above formulas (1) and (4) (and the above formula (5)) can be made into polyimide by dehydration ring closure. Although the method of this imidation reaction is not particularly limited, the catalyst imidization using a basic catalyst and an acid anhydride is unlikely to cause a decrease in the molecular weight of the polyimide during the imidation reaction, and the imidation rate can be easily controlled. preferable.

Catalytic imidation is possible by stirring the polyimide precursor in an organic solvent for 1 to 100 hours in the presence of a basic catalyst and an acid anhydride.
Here, as the polyimide precursor, a solution containing the polyimide precursor obtained by polymerization of the above-described tetracarboxylic acid anhydride component and diamine component may be used as it is (without isolation).
Examples of the basic catalyst include pyridine, triethylamine, trimethylamine, tributylamine, trioctylamine and the like. Of these, pyridine is preferable because it has a suitable basicity for proceeding with the reaction.
Examples of the acid anhydride include acetic anhydride, trimellitic anhydride, pyromellitic anhydride, and the like. Among them, acetic anhydride is preferable because the obtained polyimide can be easily purified after imidization.
As an organic solvent, the solvent used at the time of the polymerization reaction of the polyimide precursor mentioned above can be used.

The reaction temperature for the catalyst imidization is preferably -20 to 250 ° C, more preferably 0 to 180 ° C. If the reaction temperature is set to a high temperature, imidization proceeds rapidly, but if it is too high, the molecular weight of the polyimide may decrease.
The amount of the basic catalyst is preferably 0.5 to 30 mol times, more preferably 2 to 20 mol times based on the acid amide group in the polyimide precursor. Further, the amount of the acid anhydride is preferably 1 to 50 mol times, more preferably 3 to 30 mol times based on the acid amide group in the polyimide precursor.
By adjusting the reaction temperature and the amount of catalyst, the imidization ratio of the resulting polyimide can be controlled.

  Although the solvent-soluble polyimide reaction solution obtained as described above can be used as it is for the production of a gate insulating film described later, the reaction solution contains an imidization catalyst and the like. It is preferable to use a purified, recovered and washed product.

The polyimide can be easily recovered by putting the reaction solution into a poor solvent that is being stirred to precipitate the polyimide and filtering it.
Although it does not specifically limit as a poor solvent used in this case, Methanol, hexane, heptane, ethanol, toluene, water etc. can be illustrated. After the precipitate is collected by filtration, it is preferably washed with the above poor solvent.
The recovered polyimide can be made into a polyimide powder by drying at normal temperature or under reduced pressure at room temperature or by heating.

If the operation of dissolving this polyimide powder in a good solvent and reprecipitating it in a poor solvent is repeated 2 to 10 times, the impurities in the polymer can be further reduced.
The good solvent used at this time is not particularly limited as long as it can dissolve the polyimide precursor or polyimide. Examples thereof include N, N-dimethylformamide, N, N-dimethylacetamide, 2-pyrrolidone, N- Examples include methyl-2-pyrrolidone, N-ethyl-2-pyrrolidone, N-vinyl-2-pyrrolidone, N-methylcaprolactam, dimethyl sulfoxide, tetramethylurea, pyridine, and γ-butyrolactone.
Further, when three or more kinds of poor solvents such as alcohols, ketones, and hydrocarbons are used as the poor solvent used for reprecipitation, the purification efficiency is further improved.

[Image forming underlayer coating solution]
The underlayer film for image formation of the present invention can be formed using an image forming underlayer film coating solution. The image-forming underlayer film coating solution is a coating solution that contains the polyimide precursor, the polyimide, and a solvent, and can further contain a coupling agent and a surfactant described later if desired. A polyimide precursor obtained by reacting a tetracarboxylic dianhydride component containing a tetracarboxylic dianhydride represented by the following formula (6) with a diamine component containing a diamine represented by the formula (7), or A coating solution containing polyimide obtained by dehydrating and ring-closing the polyimide precursor.
(In the formula, A represents a tetravalent organic group, and B represents Formula (2) or Formula (3).
Wherein R ¹ and R ² each independently represent a hydrogen atom or a monovalent organic group, and X is a single bond or a divalent aromatic group having 6 to 20 carbon atoms. the stands, Y is a single bond, -O -, - COO -, - OCO -, - CONH -, - CH 2 O -, - CH 2 COO- or _-CH 2 _CH 2 COO- represents, Z is fluorine atom Represents an aliphatic hydrocarbon having 3 to 26 carbon atoms which may be substituted with, R independently represents a fluorine atom, an alkoxy group having 1 to 3 carbon atoms or an alkyl group having 1 to 3 carbon atoms; t represents an integer of 0 to 3. )

  Particularly preferably, in the image-forming underlayer coating solution, Z in the formula (2) or formula (3) represents an aliphatic hydrocarbon group having 3 to 26 carbon atoms in which an arbitrary hydrogen atom is substituted with a fluorine atom. is there.

  The molecular weight of the polyimide precursor and / or polyimide used in the above-mentioned image-forming underlayer coating solution is polyethylene glycol (or polyethylene oxide) from the viewpoint of ease of handling and stability such as solvent resistance when the film is formed. The weight average molecular weight in terms of conversion (measurement result by GPC) is preferably 2,000 to 200,000, more preferably 5,000 to 50,000.

When an image-forming underlayer film is prepared using the above-mentioned image-forming underlayer coating solution and irradiated with ultraviolet rays, there is no significant difference between the polyimide precursor and the polyimide with respect to the amount of change in hydrophilicity / hydrophobicity. When the lower layer film for formation focuses on this point, the imidation rate is not particularly limited.
However, by using polyimide, it is possible to obtain a highly reliable film by low-temperature firing (180 ° C. or less) that can be used for plastic substrates, and polyimide has a lower polarity than polyimide precursor, and before ultraviolet irradiation. Since advantages such as a high water contact angle (high hydrophobicity) can be obtained, it is more preferable to use polyimide.

  On the other hand, when the above-described image forming lower layer coating solution is used for an image forming lower layer film (for example, a gate insulating film) with an emphasis on insulation, the imidation ratio of the coating solution is preferably 90% or more. However, if the solvent solubility is impaired, the imidization rate can be lowered. In this case, when forming a film, the lowermost layer is made highly imidized (high insulation) by using a blending method described later. Therefore, it is possible to maintain high insulation as the lower layer film, which is useful.

  The solvent used in the above-described image-forming underlayer coating solution is not particularly limited as long as it can dissolve the polyimide precursor or polyimide. Examples thereof include N, N-dimethylformamide, N, N-dimethylacetamide, Good solvents such as 2-pyrrolidone, N-methyl-2-pyrrolidone, N-ethyl-2-pyrrolidone, N-vinyl-2-pyrrolidone, N-methylcaprolactam, dimethylsulfoxide, tetramethylurea, pyridine, γ-butyrolactone Can be mentioned. These may be used alone or as a mixture, and a poor solvent such as alcohols, ketones and hydrocarbons may be mixed with the good solvent.

  The ratio of the solid content in the above-mentioned image-forming underlayer coating solution is not particularly limited as long as each component is uniformly dissolved in a solvent, including a coupling agent and the like described later. % By weight, for example, 5 to 20% by weight. Here, solid content means what remove | excluded the solvent from all the components of the image formation lower layer film coating liquid.

  The method for preparing the above-mentioned image-forming underlayer coating solution is not particularly limited, but a solution containing a polyimide precursor obtained by polymerization of the above-described tetracarboxylic acid anhydride component and diamine component, or obtained using this solution A polyimide reaction solution may be used as it is.

  In addition, the above-described image-forming underlayer film coating solution may further contain a coupling agent for the purpose of improving the adhesion between the coating solution and the substrate as long as the effects of the present invention are not impaired.

Examples of the coupling agent include functional silane-containing compounds and epoxy group-containing compounds. Specifically, 3-aminopropyltrimethoxysilane, 3-aminopropyltriethoxysilane, 2-aminopropyltrimethoxy Silane, 2-aminopropyltriethoxysilane, N- (2-aminoethyl) -3-aminopropyltrimethoxysilane, N- (2-aminoethyl) -3-aminopropylmethyldimethoxysilane, 3-ureidopropyltrimethoxy Silane, 3-ureidopropyltriethoxysilane, N-ethoxycarbonyl-3-aminopropyltrimethoxysilane, N-ethoxycarbonyl-3-aminopropyltriethoxysilane, N-trimethoxysilylpropyltriethylenetriamine, N-triethoxy Siri Propyltriethylenetriamine, 10-trimethoxysilyl-1,4,7-triazadecane, 10-triethoxysilyl-1,4,7-triazadecane, 9-trimethoxysilyl-3,6-diazanonyl acetate, 9- Triethoxysilyl-3,6-diazanonyl acetate, N-benzyl-3-aminopropyltrimethoxysilane, N-benzyl-3-aminopropyltriethoxysilane, N-phenyl-3-aminopropyltrimethoxysilane, N -Phenyl-3-aminopropyltriethoxysilane, N-bis (oxyethylene) -3-aminopropyltrimethoxysilane, N-bis (oxyethylene) -3-aminopropyltriethoxysilane, ethylene glycol diglycidyl ether, polyethylene Glycol diglycid Ether, propylene glycol diglycidyl ether, tripropylene glycol diglycidyl ether, polypropylene glycol diglycidyl ether, neopentyl glycol diglycidyl ether, 1,6-hexanediol diglycidyl ether, glycerin diglycidyl ether, 2,2-dibromoneopentyl Glycol diglycidyl ether, 6-tetraglycidyl-2,4-hexanediol, N, N, N ′, N′-tetraglycidyl-m-xylenediamine, 1,3-bis (N, N-diglycidylaminomethyl) Mention may be made of compounds such as cyclohexane, N, N, N ′, N′-tetraglycidyl-4,4′-diaminodiphenylmethane.
These may be used alone or in combination of two or more.

  When the coupling agent is used, the content thereof is preferably added at 0.1 to 30 parts by weight, more preferably 1 to 20 parts by weight with respect to 100 parts by weight of the image forming lower layer coating solution. .

  Further, the above-mentioned image-forming underlayer film coating solution may contain a surfactant for the purpose of improving the coating property of the coating solution, the film thickness uniformity and the surface smoothness of the film obtained from the coating solution. .

  Although it does not restrict | limit especially as said surfactant, For example, a fluorine-type surfactant, a silicone type surfactant, a nonionic surfactant, etc. are mentioned. Examples of this type of surfactant include F-top EF301, EF303, EF352 (manufactured by Gemco), MegaFuck F171, F173, R-30 (manufactured by Dainippon Ink & Chemicals, Inc.), Florard FC430. FC431 (manufactured by Sumitomo 3M Co., Ltd.), Asahi Guard AG710, Surflon S-382, SC101, SC102, SC103, SC104, SC105, SC106 (manufactured by Asahi Glass Co., Ltd.) and the like.

  When the surfactant is used, the content thereof is preferably 0.01 to 2 parts by mass, more preferably 0.01 to 2 parts by mass with respect to 100 parts by mass of the polymer component contained in the image forming lower layer coating solution. 1 part by mass.

[About polymer blends]
In addition to the polyimide precursor or polyimide described above, the image-forming underlayer coating solution may be mixed with another polymer capable of forming a film (for example, a highly insulating polymer) to take a so-called polymer blend form. is there.
In this polymer blend, when the lower layer film for image formation is formed by appropriately adjusting the structure and the like of the contained polymer (the aforementioned polyimide precursor, polyimide, and other polymers), each in the thickness direction in the film Since a polymer concentration gradient can be generated, it can be used as a useful means.

For example, since the hydrophilicity / hydrophobicity change mainly occurs on the film surface, from this point of view, the polyimide precursor and / or polyimide having a thiol ester bond in the side chain is the upper layer (surface layer) of the lower layer film for image formation. ) Only exist.
Therefore, when the image-forming underlayer film coating liquid is in the form of a polymer blend (hereinafter, the coating liquid of this form is referred to as a blend coating liquid), the blending liquid of the polyimide precursor or polyimide described above is used as the blend coating liquid. 1% by mass to 100% by mass in the solid content. When it is 1% by mass or less, it is difficult to completely cover the outermost surface of the film when the blend coating solution is formed on the film, and the image forming ability may be deteriorated.

The above polymer blend is useful, for example, when the above-mentioned image forming lower layer coating solution is used for a gate insulating film application that requires particularly high insulation.
When used in gate insulating film applications, the coating solution can handle a baking temperature of 180 ° C. or lower, can be formed by coating, has solvent resistance to organic semiconductor coating solutions (polar solvents such as xylene and trimethylbenzene), low Various characteristics such as water absorption are required, but the required performance for insulation is particularly high. In order to achieve this high insulating property, the imidation rate of the above-mentioned image-forming underlayer film coating solution is required to be at least 80% or more, and in some cases 90% or more, but on the other hand, the imidation rate is 90%. If exceeded, solvent solubility is lost. At this time, the high insulating layer is positioned only in the lowermost layer of the insulating film, and the layer made of the image forming lower layer coating liquid is positioned in the upper layer, thereby maintaining the high insulating property of the insulating film, and The solubility problem can also be solved.

As described above, in order to make the lower layer of the lower layer film for image formation a high insulating layer and the upper layer to be a hydrophilic / hydrophobic conversion layer, it is possible to sequentially laminate these layers, but the operation is complicated. .
At this time, the material of the high insulating layer and the material of the hydrophilic / hydrophobic conversion layer (that is, the aforementioned polyimide precursor and / or polyimide) are mixed, and the polarity or molecular weight of the upper layer material is compared with that of the lower layer. When the mixture is applied to the substrate and dried, the upper layer material moves to the surface and forms a layer while the solvent evaporates. ) Can be easily controlled.

The most preferable material for forming a highly insulating film capable of forming the lower layer is soluble polyimide. When soluble polyimide is used as the lower layer material, from the viewpoint of insulation, it is desirable that the imidation ratio of the polyimide in the solution is high, and it is at least 50% or more, preferably 80% or more, and most preferably 90% or more.
Other materials that can be used as the lower layer material include general organic polymers such as epoxy resin, acrylic resin, polypropylene, polyvinyl alcohol, polyvinyl phenol, polyisobutylene, and polymethyl methacrylate.
Preferred soluble polyimides include soluble polyimides composed of one or more structures selected from the group consisting of the structure of formula (16).

  (In the formula, A represents a tetravalent organic group consisting of an aliphatic ring or an aliphatic group, and D represents a divalent organic group)

  The molecular weight of the soluble polyimide is preferably 2,000 to 200,000, more preferably 5,000 to 50,000 in terms of polyethylene glycol (or polyethylene oxide) weight average molecular weight (measurement result by GPC). It is desirable to use it.

In the formula (16), specific examples of A include tetravalent organic groups selected from A-1 to A-25, and specific examples of D include D-1 to D-57. Among these, from the viewpoint of high solubility of the soluble polyimide, particularly preferable structures of A are A-5, A-6, A-16, A-18, A-19, A-20, A-21, A-22 and A-25 are tetravalent organic groups, and the structure of D is D-7, D-8, D-9, D-12, D-19, D-20, D-22, D- 29, D-39, D-41, and D-42.
Such soluble polyimides can be used alone or in combination.

  In addition, when the polymer blend is used for, for example, an organic transistor application requiring a film thickness of around 400 nm, the polyimide precursor and / or the polyimide blend required for providing an upper layer (hydrophobic / hydrophobic conversion layer) The content ratio of may be 1% by mass or more. If the amount is too small, there may be a large variation in the surface properties of the lower layer film for image formation. Preferably it is 5 mass% or more.

[Manufacturing method of coating film and lower layer film for image formation]
Dip method, spin coat method, transfer printing on general-purpose plastic substrate such as polypropylene, polyethylene, polycarbonate, polyethylene terephthalate, polyethersulfone, polyethylene naphthalate, polyimide, glass substrate, etc. A coating film can be formed by coating by a method, a roll coating method, an ink jet method, a spray method, a brush coating, etc., and then pre-drying with a hot plate or an oven. Thereafter, the coating film is heated to form an image forming lower layer film that can be used as an image forming lower layer film or an insulating film.

Although it does not specifically limit as a method of the said heat processing, The method performed in a suitable atmosphere, ie, inert gas, such as air | atmosphere and nitrogen, a vacuum, etc. can be illustrated using a hotplate and oven.
The firing temperature is preferably 180 ° C. to 250 ° C. from the viewpoint of promoting thermal imidization of the polyimide precursor, and more preferably 180 ° C. or less from the viewpoint of forming a film on a plastic substrate.
Firing may be performed at two or more stages. The uniformity of the film obtained by baking in steps can be further increased.

  Further, when the image-forming underlayer film is produced, the image-forming underlayer film coating solution is in a form containing a polyimide precursor and / or polyimide and the above-mentioned solvent, and thus can be used as it is for application to a substrate. For the purpose of adjustment or ensuring the flatness of the coating film, improving the wettability of the coating solution to the substrate, and adjusting the surface tension, polarity and boiling point of the coating solution, the above-mentioned solvents, and various other types A solvent may be added and used as a coating solution.

  Specific examples of such a solvent include 1-methoxy-2 such as ethyl cellosolve, butyl cellosolve, ethyl carbitol, butyl carbitol, ethyl carbitol acetate, and ethylene glycol in addition to the solvents described in the above paragraph [0084]. -Propanol, 1-ethoxy-2-propanol, 1-butoxy-2-propanol, 1-phenoxy-2-propanol, propylene glycol monoacetate, propylene glycol diacetate, propylene glycol-1-monomethyl ether-2-acetate, propylene Glycol-1-monoethyl ether-2-acetate, dipropylene glycol, 2- (2-methoxypropoxy) propanol, 2- (2-ethoxypropoxy) propanol and 2- (2-butoxypropoxy) Shi) propylene glycol derivatives such as propanol, methyl lactate ester, ethyl lactate esters, lactate n- propyl ester, lactate n- butyl ester, lactic acid derivatives such as lactic isoamyl ester. These may be used alone or in combination.

From the viewpoint of improving the storage stability of the coating solution and the film thickness uniformity of the coating film, 20 to 80% by mass of the total amount of solvent is N, N-dimethylformamide, N, N-dimethylacetamide, N-methyl. It is preferable to use at least one solvent selected from 2-pyrrolidone, γ-butyrolactone, and dimethyl sulfoxide.
Although the density | concentration of a coating liquid does not have a restriction | limiting in particular, 0.1 thru | or 30 mass% is preferable as a solid content density | concentration of a polyimide precursor and a polyimide, More preferably, it is 1 thru | or 10 mass%. These are arbitrarily set according to the specifications of the coating apparatus and the film thickness to be obtained.

  When the underlayer film for image formation of the present invention prepared as described above is used as the underlayer film for image formation, if the film thickness is too thin, the patterning property after ultraviolet irradiation is reduced, and if it is too thick, the surface uniformity is low. Damaged. Accordingly, the film thickness is preferably 5 nm to 1000 nm, more preferably 10 nm to 300 nm, and most preferably 20 nm to 100 nm.

  Further, the lower layer film for image formation of the present invention can also function as an insulating film when the insulating property is sufficiently high. In this case, the lower layer film for image formation is disposed directly on the gate electrode, for example, in an organic FET element and used as a gate insulating film. At that time, the film thickness of the lower layer film for image formation is preferably larger than that used for the lower layer film for image formation for the purpose of ensuring insulation. The film thickness is preferably 20 nm to 1000 nm, more preferably 50 nm to 800 nm, and most preferably 100 nm to 500 nm.

[Method for Manufacturing Image Forming Electrode]
An image forming electrode can be produced by irradiating the image forming lower layer film of the present invention with ultraviolet rays in a pattern and subsequently applying an image forming liquid described later.

In the present invention, the method of irradiating the image forming lower layer film with ultraviolet rays in a pattern is not particularly limited. For example, the method of irradiating through a mask on which an electrode pattern is drawn, the electrode pattern using laser light The drawing method etc. are mentioned.
The material and shape of the mask are not particularly limited, as long as the region requiring the electrode transmits ultraviolet light and the other region does not transmit ultraviolet light.

  At this time, the wavelength of ultraviolet rays to be used is generally in the range of 200 nm to 500 nm, and it is desirable to select and use the wavelength of ultraviolet rays appropriately according to the type of the image forming lower layer film to be used. Specific examples include wavelengths such as 248 nm, 254 nm, 303 nm, 313 nm, and 365 nm. Particularly preferred are 248 nm and 254 nm.

  The surface energy of the underlayer film for image formation of the present invention is gradually increased by irradiation with ultraviolet rays, and is saturated with a sufficient irradiation amount. This increase in surface energy results in a decrease in the contact angle of the image forming liquid, and as a result, the wettability of the image forming liquid in the ultraviolet irradiation section is improved.

  Therefore, when the image forming liquid is applied on the image forming lower layer film of the present invention after the ultraviolet irradiation, the image forming liquid is self-organized along the pattern shape drawn as the difference in surface energy on the image forming lower layer film. Patterns can be formed automatically, and electrodes having an arbitrary pattern shape can be obtained.

For this reason, it is necessary to irradiate the lower layer film for image formation with an amount of ultraviolet light that sufficiently changes the contact angle of the image forming solution, but it is 20 J / cm ² from the viewpoint of energy efficiency and shortening of the manufacturing process. preferably less, more preferably 10J / cm ² or less, and most preferably 5 J / cm ² or less.

In addition, the larger the difference in the contact angle of the image forming liquid between the UV-irradiated part and the non-irradiated part of the image-forming underlayer film, the easier the patterning becomes, and it becomes possible to process the electrode into a complicated pattern or a fine pattern shape. Become. Therefore, the amount of change in contact angle due to ultraviolet irradiation is preferably 5 ° or more, more preferably 10 ° or more, and most preferably 20 ° or more.
For the same reason, it is preferable that the contact angle of the image forming liquid is 30 ° or more in the ultraviolet non-irradiated portion and 20 ° or less in the ultraviolet irradiated portion.
Currently, water is often used as the solvent for the image forming solution. Therefore, when evaluating the performance of the lower layer film, the amount of change in the contact angle of the image forming solution is simply replaced with the amount of change in the contact angle of water. May be evaluated.

  The image forming liquid in the present invention is a coating liquid that can be used as a functional thin film by evaporating the solvent contained therein after being applied to a substrate. For example, the charge transporting substance is at least one kind. Examples thereof include those dissolved or uniformly dispersed in a solvent. Here, the charge transportability is synonymous with conductivity, and means any one of hole transportability, electron transportability, and both charge transportability of holes and electrons.

The charge transporting substance is not particularly limited as long as it has conductivity capable of transporting holes or electrons. Examples thereof include inorganic materials such as metal fine particles such as gold, silver, copper, and aluminum, carbon black, fullerenes, carbon nanotubes, and organic π-conjugated polymers such as polythiophene, polyaniline, polypyrrole, polyfluorene, and derivatives thereof. Etc.
Further, for the purpose of improving the charge transport ability of the charge transport material, halogen, Lewis acid, proton acid, transition metal compound (specific examples include Br ₂ , I ₂ , Cl ₂ , FeCl ₃ , MoCl ₅ , BF ₃ , AsF ₅ , SO ₃ , HNO ₃ , H ₂ SO ₄ , polystyrene sulfonic acid, etc.) or alkali metals, alkylammonium ions (specific examples are Li, Na, K, Cs, tetraethyleneammonium, tetoabutyl) A charge donating substance such as ammonium) may be further added to the image forming solution as a dopant.

The solvent for the image forming solution is not particularly limited as long as it dissolves or uniformly disperses the charge transporting substance or dopant. However, from the viewpoint of obtaining an accurate electrode pattern, a sufficiently large contact angle is exhibited with respect to the non-irradiated portion of the image forming lower layer film, and damage to the image forming lower layer film of the present invention is small. Since it is preferable, water and various alcohols are preferable.
N, N-dimethylformamide, N, N-dimethylacetamide, 2-pyrrolidone, N-methyl-2-pyrrolidone, N-ethyl-2-pyrrolidone, N-vinyl-2-pyrrolidone, N-methylcaprolactam, dimethyl Polar solvents such as sulfoxide and tetramethylurea are also preferable from the viewpoint that they are excellent in solubility of organic charge transport materials and exhibit a sufficiently large contact angle with respect to an unirradiated portion of the underlayer film for image formation. Is preferably used in a range where the damage to the image-forming underlayer film of the present invention is small.

  The concentration of the charge transporting substance in the image forming liquid is preferably 0.01 to 30% by mass, more preferably 0.1 to 10% by mass, and most preferably 1 to 5% by mass.

  Specific examples of the image forming liquid according to the present invention include Baytron (registered trademark) P (polyethylenedioxythiophene, manufactured by Bayer).

  The electrode according to the present invention is produced by applying the image forming liquid on the image forming lower layer film of the present invention to form a pattern and then evaporating the solvent. The method for evaporating the solvent is not particularly limited, but a uniform film-forming surface is obtained by evaporating in an appropriate atmosphere, that is, in an inert gas such as air or nitrogen, in a vacuum, or the like, using a hot plate or an oven. Can be obtained.

  The temperature for evaporating the solvent is not particularly limited, but is preferably 40 to 250 ° C. From the standpoint of maintaining the pattern shape and achieving the uniformity of the film thickness, a temperature change in two or more steps may be applied.

  Electrodes prepared from this image forming liquid are used not only as wiring for connecting electronic devices but also as electrodes of electronic devices such as field effect transistors, bipolar transistors, various diodes, and various sensors.

The electronic device according to the present invention has the electrode of the present invention.
Although the example which used the lower film | membrane for image formation of this invention for the organic FET element below is shown, this invention is not limited to this.

First, a highly doped n-type silicon substrate is prepared. The substrate is preferably cleaned in advance by cleaning with a liquid such as a detergent, alcohol, or pure water, and surface treatment such as ozone treatment or oxygen-plasma treatment is preferably performed immediately before use. A gate insulating film is formed by depositing SiO ₂ , Ta ₂ O ₅ , Al ₂ O ₃ or the like on the substrate by a method such as thermal oxidation, sputtering, CVD, or vapor deposition. The film thickness of the gate insulating layer varies depending on the use of the organic FET, but is preferably in the range of 30 nm to 1000 nm from the viewpoint of the driving voltage and the electric insulation.

  Next, a layer containing a polyimide precursor and / or a polyimide having a repeating structure represented by the general formula (1) is formed on the insulating film according to the above-described procedure. The thickness of the layer is most preferably 20 nm to 100 nm. Thereafter, ultraviolet rays are irradiated using a mask or the like so as to obtain a desired electrode shape.

  Subsequently, an image forming liquid using a polar solvent such as water is applied to the surface of the lower layer film for image formation. The applied image forming solution spreads and stabilizes quickly in the hydrophilic part (ultraviolet irradiation part) to repel the hydrophobic part (ultraviolet irradiation part), and is dried to form patterned source and drain electrodes. Is done. The application method of the image forming liquid is not particularly limited, such as a spin coating method or a casting method, but an ink jet printing method or a spray coating method that allows easy control of the liquid amount is preferable.

  Finally, it is completed by depositing an organic semiconductor material such as pentacene or polythiophene, which is an active layer of the organic FET. A method for forming the organic semiconductor material is not particularly limited, and examples thereof include vacuum deposition and solution spin coating, casting, ink jet printing, and spray coating.

  In this way, the manufactured organic FET can greatly reduce the manufacturing process, and further, an organic FET having a channel shorter than that of the mask vapor deposition method can be manufactured. Even when a semiconductor material is used, a large current can be taken out. In addition, since the image-forming lower layer film obtained by the method of the present invention also has excellent electrical insulation, it can also be used as a gate insulating layer, and the manufacturing process can be further simplified. is there.

  Hereinafter, the present invention will be described in more detail with reference to examples, but the present invention is not limited thereto.

[Measurement of number average molecular weight and weight average molecular weight]
The number average molecular weight (hereinafter referred to as Mn) and the weight average molecular weight (hereinafter referred to as Mw) of the polyimide precursor obtained according to the following synthesis examples are determined by GPC (room temperature gel permeation chromatography) according to the following apparatus and measurement conditions. And calculated as a polyethylene glycol (or polyethylene oxide) equivalent value.
GPC device: Shodex (registered trademark) (GPC-101) manufactured by Showa Denko KK
Column: Shodex (registered trademark) manufactured by Showa Denko KK (series of KD803 and KD805)
Column temperature: 50 ° C
Eluent: N, N-dimethylformamide (as additives, lithium bromide-hydrate (LiBr · H ₂ O) 30 mmol / L, phosphoric acid / anhydrous crystal (o-phosphoric acid) 30 mmol / L, tetrahydrofuran (THF) ) 10ml / L)
Flow rate: 1.0 ml / min Standard sample for creating a calibration curve:
TSK standard polyethylene oxide (Molecular weight: about 900,000, 150,000, 100,000, 30,000) manufactured by Tosoh Corporation
Polyethylene glycol (molecular weight: about 12,000, 4,000, 1,000) manufactured by Polymer Laboratory.

[Measurement of film thickness]
The film thickness of the polyimide film was peeled off with a cutter knife, and the level difference was measured using a fully automatic fine shape measuring machine (ET4000A, manufactured by Kosaka Laboratory Ltd.) with a measuring force of 10 μN and a sweep speed of 0. It was determined by measuring as .05 mm / sec.

[UV irradiation]
Ultraviolet rays were irradiated onto the polyimide film through a band-pass filter that passed light having a wavelength of 254 nm using a high-pressure mercury lamp as a light source.
In calculating the amount of exposure on the polyimide film, the illuminance of ultraviolet rays was measured by attaching a Deep UV probe having a peak sensitivity at a wavelength of 253.7 nm to an illuminometer (MODEL 306 manufactured by OAI).
The illuminance obtained was 45-50 mW / cm ² . The obtained illuminance was multiplied by the exposure time to obtain the exposure amount (J / cm ² ).

[Measurement of contact angle]
The contact angle was measured using a fully automatic contact angle meter CA-W (Kyowa Interface Chemical Co., Ltd.) in a constant temperature and humidity environment (25 ° C. ± 2 ° C., 50% RH ± 5%).
The contact angle of water was measured after the amount of liquid was 3 μL, and after resting for 5 seconds.
The contact angle of propylene glycol monomethyl ether (PGME) was measured after a liquid amount of 3.0 to 3.5 μL and after resting for 5 seconds.

<Synthesis example>
[Synthesis Example 1: Synthesis of diamine compound (DA-1: octadecyl 3,5-diaminothiobenzoate)]

Under a nitrogen atmosphere, a solution of compound [ii] (20.00 g, 69.79 mmol) and triethylamine (8.07 g, 79.76 mmol) in tetrahydrofuran (155 g) is cooled to 10 ° C. or lower to obtain compound [i] (15.33 g). , 66.47 mmol) in tetrahydrofuran (70 g) was added dropwise while paying attention to heat generation. After completion of the dropwise addition, the reaction temperature was raised to 23 ° C. and further reaction was performed. After confirming the completion of the reaction by HPLC (high performance liquid chromatograph), the reaction solution is poured into distilled water (1.8 L), the precipitated solid is filtered, washed with water, dispersed and washed with methanol (192 g), and compound [iii] is obtained. Obtained (yield: 26.4 g, yield: 83%).
¹ H-NMR (400 MHz, CDCl ₃ , δ ppm): 9.21-9.20 (1H, m), 9.07-9.06 (2H, m), 3.18 (2H, t), 1. 73-1.67 (2H, m), 1.48-1.37 (2H, m), 1.23 (28H, s), 0.86 (3H, t).

Under a nitrogen atmosphere, a mixture of compound [iii] (19.95 g, 41.5 mmol), iron powder (reduced iron, 13.91 g, 249.0 mmol), and ethyl acetate (180 g) was heated to 70 ° C., and then chlorinated. A 10% aqueous solution of ammonium (6.66 g, 124.5 mmol) was added dropwise. After completion of the reaction by HPLC, the solid was filtered by Celite filtration. After washing with 200 mL each of ethyl acetate and distilled water, the aqueous layer was removed, and the organic layer was washed 3 times with distilled water (300 mL). Thereafter, the organic layer was dried over anhydrous magnesium sulfate and filtered, and then the solvent was distilled off. The obtained crude compound (DA-1) was recrystallized from methanol (104 g) to obtain compound (DA-1) (yield: 11.7 g, yield: 67%).
¹ H-NMR (400 MHz, CDCl ₃ , δ ppm): 6.69 (2H, dd), 6.18 (1H, t), 3.69 (4H, brs), 3.00 (2H, t), 1 .66-1.56 (2H, m), 1.42-1.25 (30H, m), 0.88 (3H, t).

[Synthesis Example 2: Synthesis of polyimide precursor (PI-1)]
Under a nitrogen stream, 1.2621 g (0.003 mol) of octadecyl 3,5-diaminothiobenzoate (DA-1) prepared in Synthesis Example 1 was placed in a 50 mL four-necked flask, and N-methyl-2-pyrrolidone was added. (Hereinafter referred to as NMP) After dissolving in 10.42 g, 0.5766 g (0.003 mol) of 1,2,3,4-cyclobutanetetracarboxylic anhydride (hereinafter referred to as CBDA) was added, and this was stirred at 23 ° C. for 10 hours. Then, a polymerization reaction was carried out and further diluted with NMP to obtain an 8% by mass solution of a polyimide precursor (PI-1).
The number average molecular weight (Mn) and the weight average molecular weight (Mw) of the obtained polyimide precursor (PI-1) were Mn = 11,650 and Mw = 28,380, respectively.

[Synthesis Example 3: Synthesis of polyimide precursor (PI-2)]
Under a nitrogen stream, DA835 0.8835 g (0.0021 mol) and p-phenylenediamine (p-PDA) 0.0973 g (0.0009 mol) were placed in a 50 mL four-necked flask, and NMP 8.83 g was added. After dissolution, 0.5766 g (0.00294 mol) of CBDA was added, this was stirred at 23 ° C. for 10 hours to conduct a polymerization reaction, and further diluted with NMP to obtain 6 of polyimide precursor (PI-2). A mass% solution was obtained.
The number average molecular weight (Mn) and the weight average molecular weight (Mw) of the obtained polyimide precursor (PI-2) were Mn = 34,670 and Mw = 97,560, respectively.

[Synthesis Example 4: Synthesis of Polyimide Precursor (PI-3) of Comparative Example]
In a nitrogen stream, 15.065 g (0.040 mol) of 1-octadecyloxy-2,4-diaminobenzene (APC18) was placed in a 200 mL four-necked flask, dissolved in 127.6 g of NMP, and then CBDA 7 .45 g (0.038 mol) was added, this was stirred at 23 ° C. for 12 hours to carry out a polymerization reaction, and further diluted with NMP to obtain a 6 wt% solution of polyimide precursor (PI-3).
The number average molecular weight (Mn) and the weight average molecular weight (Mw) of the obtained polyamide precursor (PI-3) were Mn = 16,000 and Mw = 48,000, respectively.

[Synthesis Example 5: Diamine Compound (DA-2)]
Synthesis of DA-2

Under a nitrogen atmosphere, compound [iv] (42.63 g, 209.9 mmol), compound [v] (102.97 g, 230.9 mmol), copper powder (29.35 g, 461.8 mmol), 2,2′-bipyridyl (3.28 g, 20.99 mmol) and a mixture of dimethyl sulfoxide (341 g) were stirred at 120 ° C. After confirming the completion of the reaction by HPLC, the reaction solution was added to distilled water (2730 g), and the filtrate was washed with filtration, distilled water (2 L), and ethyl acetate (1.5 L). Next, hexane (500 g) was added to the filtrate, and the organic layer was washed 3 times with saturated brine (1 L) and dried over anhydrous magnesium sulfate. Then, the compound [vi] was obtained by filtering and evaporating the solvent (yield: 75.33 g, yield: 81%).
¹ H-NMR (400 MHz, CDCl ₃ , δ ppm): 7.48 (2H, d), 7.32 (2H, d), 2.52 (3H, s).

Under a nitrogen atmosphere, N-fluoro-N ′-(chloromethyl) triethylenediamine bis (tetrafluoroborate) was added to a solution of compound [vi] (52.00 g, 117.6 mmol) in acetonitrile (347 g) / pure water (17 g). ) (43.63 g, 123.2 mmol) was added, and the reaction was performed at 23 ° C. After confirming the completion of the reaction by HPLC, the solvent was distilled off. Next, dichloromethane (1.2 L) was added, and saturated aqueous sodium hydrogen carbonate (700 mL) was added little by little. After removing the aqueous layer, the organic layer was washed three times with saturated brine (700 mL), and the organic layer was dried over anhydrous magnesium sulfate. Then, filtration and solvent distillation were performed and compound [vii] was obtained (yield: 48.05 g, yield: 89%).
¹ H-NMR (400 MHz, CDCl ₃ , δ ppm): 7.81 (2H, d), 7.78 (2H, d), 2.71 (3H, s).

Acetic anhydride (46.39 g, 454.4 mmol) was added to compound [vii] (26.03 g, 56.8 mmol) under a nitrogen atmosphere, and the reaction was carried out under reflux with heating. After confirmation of completion of the reaction by HPLC, the solvent was distilled off to obtain a crude product of compound [viii]. The resulting crude product was purified by column chromatography (SiO ₂ , hexane / ethyl acetate) to obtain compound [viii] (yield: 24.11 g, yield: 85%).
¹ H-NMR (400 MHz, CDCl ₃ , δ ppm): 7.54 (4H, s), 5.50 (2H, s), 2.14 (3H, s).

Under a nitrogen atmosphere, 28% aqueous ammonia solution (13.73 g) was added to a methanol (150 g) solution of compound [viii] (37.67 g, 75.3 mmol), and the mixture was stirred at 23 ° C. After confirming the completion of the reaction by HPLC, the pH was adjusted to 6 with 35% hydrochloric acid, and then the solvent was distilled off. Thereafter, the crude product was dissolved with dichloromethane (1 L), washed 3 times with saturated saline (500 mL), and dried over anhydrous magnesium sulfate. Thereafter, filtration and evaporation of the solvent yielded compound [ix] (yield: 31.28 g, yield: 97%).
¹ H-NMR (400 MHz, CDCl ₃ , δ ppm): 7.44 (2H, d), 7.37 (2H, d), 3.61 (1H, s).

Under a nitrogen atmosphere, a solution of compound [ix] (31.00 g, 72.4 mmol) and triethylamine (7.33 g, 72.4 mmol) in tetrahydrofuran (139 g) was cooled to 10 ° C. or lower to obtain compound [i] (15.90 g). , 68.95 mmol) in tetrahydrofuran (100 g) was added dropwise, taking care of the exotherm. After completion of the dropwise addition, the reaction temperature was raised to 23 ° C. and further reaction was performed. After confirming the completion of the reaction by HPLC, the reaction solution was added to distilled water (1.9 L), and the precipitated solid was filtered, washed with water, and then recrystallized from 2-propanol (257 g) to obtain compound [x]. (Yield: 27.01 g, yield: 63%).
¹ H-NMR (400 MHz, CDCl ₃ , δ ppm): 9.30 (1H, t), 9.15 (2H, d), 7.74 (4H, q).

Under a nitrogen atmosphere, a mixture of compound [x] (14.00 g, 22.5 mmol), 3% platinum carbon (0.3% iron supported, water content, 2.8 g, 20 wt%), methanol (210 g) was present in the presence of hydrogen. Under stirring at 23 ° C. After confirming the completion of the reaction by HPLC, the reaction mixture was filtered through celite, the celite was washed with methanol (50 mL), and the solvent was distilled off. The crude product (DA-2) obtained was dispersed and washed with 2-propanol (60 g), filtered and dried to obtain compound (DA-2) (yield: 9.13 g, yield: 72%).
¹ H-NMR (400 MHz, CDCl ₃ , δ ppm): 7.65 (4H, s), 6.73 (2H, d), 6.24 (1H, t), 3.76 (4H, brs).

[Synthesis Example 6: Diamine Compound (DA-3)]
Synthesis of DA-3

Under nitrogen atmosphere, compound [iv] (27.05 g, 133.2 mmol), compound [xi] (80.00 g, 146.5 mmol), copper powder (18.62 g, 293.0 mmol), 2,2′-bipyridyl (2.08 g, 13.32 mmol) and a mixture of dimethyl sulfoxide (216 g) were stirred at 120 ° C. After confirming the completion of the reaction by HPLC, the reaction solution was added to distilled water (1730 g), and the filtrate was washed with filtration, distilled water (1 L) and ethyl acetate (1 L). Next, hexane (500 g) was added to the filtrate, and the organic layer was washed 3 times with saturated brine (1 L) and dried over anhydrous magnesium sulfate. Then, the compound [xii] was obtained by filtering and distilling a solvent off (yield: 65.72 g, yield: 91%).
¹ H-NMR (400 MHz, CDCl ₃ , δ ppm): 7.58 (2H, d), 7.47 (2H, d), 2.54 (3H, s).

Under a nitrogen atmosphere, N-fluoro-N ′-(chloromethyl) triethylenediamine bis (tetrafluoroborate) was added to a solution of compound [xii] (50.00 g, 92.21 mmol) in acetonitrile (333 g) / pure water (17 g). ) (32.67 g, 92.21 mmol) was added, and the reaction was performed at 23 ° C. After confirming the completion of the reaction by HPLC, the solvent was distilled off. Next, dichloromethane (800 mL) was added, and saturated aqueous sodium hydrogen carbonate (500 mL) was added little by little. After removing the aqueous layer, the organic layer was washed three times with saturated brine (500 mL), and the organic layer was dried over anhydrous magnesium sulfate. Then, filtration and solvent distillation were performed and compound [xiii] was obtained (yield: 47.98 g, yield: 93%).
¹ H-NMR (400 MHz, CDCl ₃ , δ ppm): 7.81 (2H, d), 7.77 (2H, d), 2.78 (3H, s).

Under a nitrogen atmosphere, trifluoroacetic anhydride (220.56 g, 1.05 mol) was added to compound [xiii] (70.63 g, 126.5 mmol), and the reaction was carried out under reflux. After confirming the completion of the reaction by HPLC, the solvent was distilled off to obtain a crude product. Next, methanol (226 g) and triethylamine (211.89 g) were added, and the solvent was distilled off after stirring at 23 ° C. for 30 minutes. Further, the obtained crude product was dissolved in ethyl acetate (1 L), washed with saturated aqueous ammonium chloride (1 L) and saturated brine (1 L) twice, the organic layer was dried over magnesium sulfate, The compound [xiv] was obtained by leaving (yield: 64.7 g, yield: 97%).
¹ H-NMR (400 MHz, CDCl ₃ , δ ppm): 7.44 (2H, d), 7.36 (2H, d), 3.61 (1H, s).

Under a nitrogen atmosphere, a solution of compound [xiv] (69.00 g, 130.62 mmol) and triethylamine (13.22 g, 130.62 mmol) in tetrahydrofuran (290 g) is cooled to 10 ° C. or lower to obtain compound [i] (28.68 g). , 124.40 mmol) in tetrahydrofuran (145 g) was added dropwise, taking care of the exotherm. After completion of the dropwise addition, the reaction temperature was raised to 23 ° C. and further reaction was performed. After confirming the completion of the reaction by HPLC, the reaction solution was added to distilled water (3.5 L), the precipitated solid was filtered, washed with water, and then recrystallized from 2-propanol (270 g) to obtain compound [xv]. (Yield: 79.99 g, yield: 88%).
¹ H-NMR (400 MHz, CDCl ₃ , δ ppm): 9.27 (1H, t), 9.17 (2H, d), 7.61 (4H, q).

Under a nitrogen atmosphere, a mixture of compound [xvii] (8.00 g, 11.1 mmol), 3% platinum carbon (0.3% iron supported, water content, 1.6 g, 20 wt%), methanol (120 g) was present in the presence of hydrogen. Under stirring at 23 ° C. After confirming the completion of the reaction by HPLC, the reaction mixture was filtered through celite, the celite was washed with methanol (30 mL), and the solvent was distilled off. The obtained crude compound (DA-3) was dispersed and washed with 2-propanol (28 g), filtered and dried to obtain compound (DA-3) (yield: 5.6 g, yield: 76%).
¹ H-NMR (400 MHz, CDCl ₃ , δ ppm): 7.65 (4H, s), 6.73 (2H, d), 6.24 (1H, t), 3.76 (4H, brs).

[Synthesis Example 7: Diamine Compound (DA-4)]
Synthesis of DA-4

Under a nitrogen atmosphere, a solution of compound [xvi] (21.87 g, 45.54 mmol) and triethylamine (4.61 g, 45.54 mmol) in tetrahydrofuran (90 g) is cooled to 10 ° C. or lower, and compound [i] (10.00 g , 43.37 mmol) in tetrahydrofuran (60 g) was added dropwise while paying attention to heat generation. After completion of the dropwise addition, the reaction temperature was raised to 23 ° C. and further reaction was performed. After confirming the completion of the reaction by HPLC (High Performance Liquid Chromatography), the reaction solution was added to distilled water (1.2 L), the precipitated solid was filtered, washed with water, dispersed and washed with 2-propanol (232 g), and the compound [xvii (Yield: 27.69 g, Yield: 95%).
¹ H-NMR (400 MHz, DMSO-d ₆ , δ ppm): 9.06 (1H, t), 8.86 (2H, d), 3.44 (2H, t), 2.79-2.66 ( 2H, m).

Under a nitrogen atmosphere, a mixture of compound [xvii] (25.00 g, 37.1 mmol), iron powder (reduced iron, 12.42 g, 222.5 mmol), and ethyl acetate (225 g) was heated to 70 ° C. and then chlorinated. A 10% aqueous solution of ammonium (5.95 g, 111.3 mmol) was added dropwise. After confirming the completion of the reaction by HPLC, the solid was filtered by Celite filtration. After washing with 500 mL each of ethyl acetate and distilled water, the aqueous layer was removed, and the organic layer was washed 3 times with distilled water (500 mL). Thereafter, the organic layer was dried over anhydrous magnesium sulfate and filtered, and then the solvent was distilled off. The obtained crude compound (DA-4) was dispersed and washed with hexane (60 g), filtered and dried to obtain compound (DA-4) (yield: 19.5 g, yield: 85%). ).
¹ H-NMR (400 MHz, DMSO-d ₆ , δ ppm): 6.36 (2H, d), 6.06 (1H, t), 5.14 (4H, brs), 3.19 (2H, t) , 2.64-2.51 (2H, m).

[Synthesis Example 8: Synthesis of polyimide (PI-4)]
In a 100 mL four-necked flask in a nitrogen stream, 2,2-bis (4-aminophenoxyphenyl) propane (hereinafter BAPP) 3.55837 g (8.73 mmol), DA-2 0.1518 g (0.27 mmol) Was dissolved in 36.02 g of NMP, and 2.6214 g (8.73 mmol) of 3,4-dicarboxy-1,2,3,4-tetrahydro-1-naphthalene succinic dianhydride (hereinafter TDA) was added. In addition, this was stirred at 50 ° C. for 24 hours to carry out a polymerization reaction. The obtained polyamic acid solution was diluted to 8% by mass with NMP.
To 30 g of this solution, 11 g of acetic anhydride and 5.2 g of pyridine were added as an imidization catalyst and reacted at 50 ° C. for 3 hours to obtain a polyimide solution. This solution was put into a large amount of methanol, and the resulting white precipitate was filtered and dried to obtain a white polyimide powder. It was confirmed that 90% or more of this polyimide powder was imidized by ¹ H-NMR. 2.1 g of this powder was dissolved in a mixed solvent of 27.7 g of γ-butyrolactone and 5.3 g of dipropylene glycol monomethyl ether to obtain a 6% by mass solution of polyimide (PI-4).
The number average molecular weight (Mn) and the weight average molecular weight (Mw) of the obtained polyimide (PI-4) were Mn = 14,300 and Mw = 38,000, respectively.

[Synthesis Example 9: Synthesis of polyimide (PI-5)]
In a 100 mL four-necked flask under nitrogen flow, BAPP 3.4728 g (8.46 mmol) and DA-2 0.3037 g (0.54 mmol) were added and dissolved in NMP 36.25 g, and then TDA 2.6214 g (8.73 mmol) was added, and this was stirred at 50 ° C. for 24 hours to carry out a polymerization reaction. The obtained polyamic acid solution was diluted to 8% by mass with NMP.
To 30 g of this solution, 11 g of acetic anhydride and 5.2 g of pyridine were added as an imidization catalyst and reacted at 50 ° C. for 3 hours to obtain a polyimide solution. This solution was put into a large amount of methanol, and the resulting white precipitate was filtered and dried to obtain a white polyimide powder. It was confirmed that 90% or more of this polyimide powder was imidized by ¹ H-NMR. 2.1 g of this powder was dissolved in a mixed solvent of 27.7 g of γ-butyrolactone and 5.3 g of dipropylene glycol monomethyl ether to obtain a 6% by mass solution of polyimide (PI-5).
The number average molecular weight (Mn) and the weight average molecular weight (Mw) of the obtained polyimide (PI-5) were Mn = 16,400 and Mw = 39,400, respectively.

[Synthesis Example 10: Synthesis of polyimide (PI-6)]
In a 100 mL four-necked flask under nitrogen flow, 3.6206 g (8.82 mmol) of BAPP and 0.1192 g (0.18 mmol) of DA-3 were added and dissolved in 36.05 g of NMP, and then 2.6214 g of TDA. (8.73 mmol) was added, and this was stirred at 50 ° C. for 24 hours to carry out a polymerization reaction. The obtained polyamic acid solution was diluted to 8% by mass with NMP.
To 30 g of this solution, 11 g of acetic anhydride and 5.2 g of pyridine were added as an imidization catalyst and reacted at 50 ° C. for 3 hours to obtain a polyimide solution. This solution was put into a large amount of methanol, and the resulting white precipitate was filtered and dried to obtain a white polyimide powder. It was confirmed that 90% or more of this polyimide powder was imidized by ¹ H-NMR. 2.1 g of this powder was dissolved in a mixed solvent of 27.7 g of γ-butyrolactone and 5.3 g of dipropylene glycol monomethyl ether to obtain a 6% by mass solution of polyimide (PI-6).
The number average molecular weight (Mn) and the weight average molecular weight (Mw) of the obtained polyimide (PI-6) were Mn = 20,200 and Mw = 51,400, respectively.

[Synthesis Example 11: Synthesis of polyimide (PI-7)]
In a 100 mL four-necked flask under nitrogen flow, BAPP 3.9819 g (9.7 mmol) and DA-4 0.1842 g (0.3 mmol) were added and dissolved in 40.11 g of NMP, and then 2.9126 g of TDA. (9.7 mmol) was added, and this was stirred at 50 ° C. for 24 hours to carry out a polymerization reaction. The obtained polyamic acid solution was diluted to 8% by mass with NMP.
To 30 g of this solution, 11 g of acetic anhydride and 5.2 g of pyridine were added as an imidization catalyst and reacted at 50 ° C. for 3 hours to obtain a polyimide solution. This solution was put into a large amount of methanol, and the resulting white precipitate was filtered and dried to obtain a white polyimide powder. It was confirmed that 90% or more of this polyimide powder was imidized by ¹ H-NMR. 2.1 g of this powder was dissolved in a mixed solvent of 27.7 g of γ-butyrolactone and 5.3 g of dipropylene glycol monomethyl ether to obtain a 6% by mass solution of polyimide (PI-7).
The number average molecular weight (Mn) and weight average molecular weight (Mw) of the obtained polyimide (PI-7) were Mn = 17,800 and Mw = 45,000, respectively.

[Synthesis Example 12: Synthesis of polyimide precursor (PI-8)]
In a 100 mL four-necked flask under nitrogen flow, BAPP 3.9819 g (9.7 mmol) and DA-4 0.1842 g (0.3 mmol) were added and dissolved in NMP 34.39 g, and then CBDA 1.9023 g (9.7 mmol) was added, this was stirred at 23 ° C. for 10 hours to conduct a polymerization reaction, and further diluted with NMP to obtain a 6% by mass solution of a polyimide precursor (PI-8).
The number average molecular weight (Mn) and the weight average molecular weight (Mw) of the obtained polyimide precursor (PI-8) were Mn = 14,300 and Mw = 32,100, respectively.

[Synthesis Example 13: Synthesis of polyimide (PI-9) for blending]
Under a nitrogen stream, p-phenylenediamine 4.86 g (0.045 mol), 4-hexadecyloxy-1,3-diaminobenzene 1.74 g (0.005 mol) were placed in a 200 mL four-necked flask, and NMP After dissolving in 122.5 g, 15.01 g (0.05 mol) of TDA was added, and this was stirred at room temperature for 10 hours to conduct a polymerization reaction. The obtained polyamic acid solution was diluted to 8% by mass with NMP.
To 50 g of this solution, 10.8 g of acetic anhydride and 5.0 g of pyridine were added as imidation catalysts and reacted at 50 ° C. for 3 hours to obtain a polyimide solution. This solution was put into a large amount of methanol, and the resulting white precipitate was filtered and dried to obtain a white polyimide powder. It was confirmed that 90% or more of this polyimide powder was imidized by ¹ H-NMR. 4 g of this powder was dissolved in a mixed solvent of 52.67 g of γ-butyrolactone and 10 g of dipropylene glycol monomethyl ether to obtain a 6% by mass solution of polyimide (PI-9).
The number average molecular weight (Mn) and the weight average molecular weight (Mw) of the obtained polyimide (PI-9) were Mn = 18,000 and Mw = 54,000, respectively.

[Synthesis Example 14: Preparation of polymer blend (Composition A)]
9 g of a 6 wt% solution of polyimide (PI-9) prepared in Synthesis Example 13 and 1 g of a 6 wt% solution of polyimide (PI-7) prepared in Synthesis Example 11 were mixed and stirred at room temperature for 6 hours to obtain a composition. A was obtained.

[Synthesis Example 15: Preparation of polymer blend (Composition B)]
9 g of a 6 wt% solution of polyimide (PI-9) prepared in Synthesis Example 13 and 1 g of a 6 wt% solution of polyimide (PI-8) prepared in Synthesis Example 12 were mixed and stirred at room temperature for 6 hours to obtain a composition. B was obtained.

[Synthesis Example 16: Preparation of polymer blend (composition C)]
8 g of a 6 wt% solution of polyimide (PI-9) prepared in Synthesis Example 13 and 2 g of a 6 wt% solution of polyimide (PI-8) prepared in Synthesis Example 12 were mixed together and stirred at room temperature for 6 hours. C was obtained.

The structural formulas of the tetracarboxylic acid anhydride and diamine compound synthesized or used in this example are shown below.
[Tetracarboxylic anhydride used in this example]
[Diamine used in this example]

<Example 1> Change in water contact angle Using a syringe with a 0.2-μm pore filter prepared from the PI-1 solution prepared in Synthesis Example 2 on a glass substrate with ITO (2.5 cm square, thickness 0.7 mm). The solution was dropped and applied by spin coating. Thereafter, it was heat-treated for 5 minutes on a hot plate at 80 ° C. in the atmosphere to volatilize the organic solvent, and then baked for 30 minutes on a hot plate at 210 ° C. to obtain a polyimide film having a film thickness of about 400 nm. The water contact angle θ (°) of the polyimide film was measured.
Two polyimide films were prepared in the same procedure, and after irradiating with ultraviolet rays at a dose of 20 J / cm ² or 40 J / cm ² , the water contact angle θ (°) of the film was measured.
The results are shown in Table A.

<Example 2> Change in water contact angle Except that the solution of PI-2 prepared in Synthesis Example 3 was used, three polyimide films were prepared using the same procedure as in Example 1, and each was not irradiated with ultraviolet rays. A film, a film irradiated with ultraviolet rays 20 J / cm ² , or a film irradiated with ultraviolet rays 40 J / cm ² were used, and the contact angle θ (°) of each water was measured.
The results are shown in Table A.

<Comparative example 1> Change of water contact angle Except having used the solution of PI-3 prepared by the synthesis example 4, two polyimide films were produced using the procedure similar to Example 1, and each was not irradiated with ultraviolet rays. A film or a film irradiated with ultraviolet rays 40 J / cm ² was used, and the contact angle θ (°) of water was measured.
The results are shown in Table A.

<Example 3> was prepared 3 sheets of polyimide film using the same procedure as PGME contact angle variation Example 1, respectively, not irradiated with ultraviolet rays of the film, ultraviolet 2J / cm ² the irradiated film, or ultraviolet 6J / cm ² was used as the irradiated film, and the contact angle θ (°) of PGME was measured.
The results are shown in Table B.

<Comparative example 2> PGME contact angle change Except having used the solution of PI-3 prepared by the synthesis example 4, two polyimide films were produced using the procedure similar to Example 1, and each was not irradiated with ultraviolet rays. The contact angle θ (°) of PGME was measured using a film or a film irradiated with ultraviolet rays 6 J / cm ² .
The results are shown in Table B.

<Example 4> PGME contact angle variation ITO-coated glass substrate (2.5 cm square, thickness 0.7 mm), the dropping a solution of PI-4 was manufactured by adjusting in Synthesis Example 8 in a syringe with a 0.2μm pore filter And applied by spin coating. Thereafter, heat treatment was performed for 5 minutes on an 80 ° C. hot plate in the atmosphere to volatilize the organic solvent, and then baked for 30 minutes on a 180 ° C. hot plate to obtain a polyimide film having a film thickness of about 400 nm. The contact angle of the PGME solution of this polyimide film was measured.
One polyimide film was prepared in the same procedure, and ultraviolet rays were irradiated at a dose of 1 J / cm ² to measure the contact angle θ (°) of PGME.
The results are shown in Table C.

<Example 5> PGME contact angle change Two polyimide films were prepared using the same procedure as in Example 4 except that PI-5 prepared in Synthesis Example 9 was used. The film was irradiated with ultraviolet light 1 J / cm ² and the contact angle θ (°) of PGME was measured.
The results are shown in Table C.

<Example 6> PGME contact angle change Two polyimide films were prepared using the same procedure as in Example 4 except that PI-6 prepared in Synthesis Example 10 was used. The film was irradiated with ultraviolet light 1 J / cm ² and the contact angle θ (°) of PGME was measured.
The results are shown in Table C.

<Example 7> PGME contact angle change Two polyimide films were prepared using the same procedure as in Example 4 except that the composition A prepared in Synthesis Example 14 was used. The film was irradiated with ultraviolet light 1 J / cm ² and the contact angle θ (°) of PGME was measured.
The results are shown in Table C.

<Example 8> PGME contact angle change Two polyimide films were prepared using the same procedure as in Example 6 except that the composition C prepared in Synthesis Example 16 was used. The film was irradiated with ultraviolet light 1 J / cm ² and the contact angle θ (°) of PGME was measured.
The results are shown in Table C.

As shown in Table A, Table B, and Table C, in Examples using polyimides and polyimide precursors prepared from diamines having thiol bonds in the side chains, the contact angle of PGME after UV irradiation was any case. It changed a lot.
On the other hand, in Comparative Examples 1 and 2 using a polyimide precursor (PI-3) produced without using a diamine having a thiol bond in the side chain, the amount of change in the contact angle of water or PGME was small. .
This result shows that the side chain of the polyimide precursor has a structure in which a hydrophobic group exists via a thiol ester group, that is, the thiol ester group is photodegraded by ultraviolet irradiation, and the hydrophobic part of the side chain is mainly present. It seems that the cleavage and separation from the chain led to a large change in hydrophilicity / hydrophobicity.

<Example 9> Evaluation of electrode patterning property A solution of PI-4 prepared in Synthesis Example 8 was dropped onto a glass substrate with ITO (2.5 cm square, thickness 0.7 mm) with a syringe with a 0.2 μm pore filter. It was applied by spin coating. Thereafter, heat treatment was performed for 5 minutes on an 80 ° C. hot plate in the atmosphere to volatilize the organic solvent, and then baked for 30 minutes on a 180 ° C. hot plate to obtain a polyimide film having a film thickness of about 400 nm. This polyimide film was irradiated with ultraviolet rays of 1 J / cm ² through a photomask (line and space with a line width of 100 μm and a pitch of 100 μm) to make part of the polyimide hydrophilic. Next, a small amount of the silver fine particle dispersion was dropped on the ultraviolet irradiation part and baked on a hot plate at 180 ° C. for 60 minutes to form a silver electrode having a thickness of 50 nm.
A photomicrograph of this silver electrode is shown in FIG. The film made of PI-4 was able to form a silver electrode having a target line width.

<Example 10> Evaluation of electrode patterning property A polyimide film was formed using the same procedure as in Example 9 except that the composition A prepared in Synthesis Example 14 was used, and a photomask (line width) was formed on this polyimide film. A portion of polyimide was hydrophilized by irradiating ultraviolet rays of 1 J / cm ² through a line and space of 100 μm and a pitch of 100 μm. Next, a small amount of the silver fine particle dispersion was dropped on the ultraviolet irradiation part and baked on a hot plate at 180 ° C. for 60 minutes to form a silver electrode having a thickness of 50 nm.
A photomicrograph of this silver electrode is shown in FIG. The film made of the composition A was able to form a silver electrode having a target line width.

<Comparative Example 3> Evaluation of electrode patterning property A polyimide film was formed using the same procedure as in Example 11 except that PI-3 prepared in Synthesis Example 4 was used and the firing temperature was 210 ° C. The film was irradiated with ultraviolet rays of 1 J / cm ² through a photomask (line and space with a line width of 100 μm and a pitch of 100 μm). Thereafter, a small amount of the silver fine particle dispersion was dropped, but the electrode could not be formed because the ultraviolet-irradiated part was not hydrophilized.

The results of Examples 9 to 10 and Comparative Example 3 are shown in Table D.
Whereas a film composed of PI-4 having a thiol ester bond and composition A was sufficiently hydrophilic at an ultraviolet irradiation amount of 1 J / cm ² , a silver electrode having a line width of 100 μm was possible. Thus, the film made of the composition D having no thiol ester bond did not change to hydrophilicity sufficiently at an ultraviolet irradiation amount of 1 J / cm ² , and electrode formation was impossible.

<Example 11> Insulation To a glass substrate with ITO (2.5 cm square, thickness 0.7 mm), the PI-1 solution prepared in Synthesis Example 2 was dropped using a syringe with a 0.2 μm pore filter. It was applied by spin coating. Thereafter, in the atmosphere, heat treatment was performed on an 80 ° C. hot plate for 5 minutes to volatilize the organic solvent, and then baked on a 210 ° C. hot plate for 30 minutes to obtain a polyimide film having a thickness of about 450 nm.
Next, in order to obtain a good contact between the ITO electrode and the probe of the measuring device, a portion of the polyimide film is scraped to expose the ITO, and then a diameter of 1.0 mm is formed on the polyimide film and on the ITO using a vacuum deposition apparatus. An aluminum electrode having a thickness of 100 nm was laminated. The vacuum deposition conditions at this time were room temperature, a degree of vacuum of 3 × 10 ⁻³ Pa or less, and an aluminum deposition rate of 0.3 nm / sec or less. Thus, the sample for the current-voltage characteristic evaluation of a polyimide film was produced by forming an electrode on the upper and lower sides of a polyimide film.
The prepared sample was immediately measured for current-voltage characteristics in a nitrogen atmosphere. The measurement voltage was from 0V to 90V in 2V increments. At this time, the relative dielectric constant of the polyimide film was 3.37, and the leakage current density was 3 × 10 ⁻¹⁰ A / cm ² . The polyimide film did not break down at an electric field of 2 MV / cm.
FIG. 3 shows measurement results of current-voltage characteristics in a nitrogen atmosphere.

Next, the same sample as above was allowed to stand in the atmosphere (25 degrees, humidity 45%) for 15 hours, and then current-voltage characteristics were measured. The measurement voltage was from 0V to 90V in 2V increments. The leakage current density of the sample at this time was 1.8 × 10 ⁻⁷ A / cm ² .
FIG. 4 shows the measurement results of current-voltage characteristics in the atmosphere.

<Example 12> Insulating property A sample for current-voltage characteristics was prepared using the same procedure as in Example 11 except that the baking temperature of the polyimide film was 230 ° C. At this time, the relative dielectric constant of the polyimide film was 3.14, and the leakage current density was 1.0 × 10 ⁻¹⁰ A / cm ² . The polyimide film did not break down at an electric field of 2 MV / cm.
Next, the same sample as described above was allowed to stand in the atmosphere (25 degrees, humidity 45%) for 15 hours, and then the current-voltage characteristics were measured. The measurement voltage was from 0V to 90V in 2V increments. The leakage current density of the sample at this time was 1.8 × 10 ⁻⁸ A / cm ² .
FIG. 3 shows measurement results of current-voltage characteristics in a nitrogen atmosphere, and FIG.

<Example 13> Insulation To a glass substrate with ITO (2.5 cm square, thickness 0.7 mm), the solution of PI-4 prepared in Synthesis Example 8 was dropped with a syringe with a 0.2 μm pore filter, The coating was performed by a spin coating method. Thereafter, in the atmosphere, the organic solvent was volatilized by heating on an 80 ° C. hot plate for 5 minutes, and then baked on a 180 ° C. hot plate for 30 minutes to obtain a polyimide film having a film thickness of about 400 nm. Next, in order to obtain a good contact between the ITO electrode and the probe of the measuring device, a part of the polyimide film is scraped to expose the ITO, and then a diameter of 1.0 mm is formed on the polyimide film and on the ITO using a vacuum deposition apparatus. An aluminum electrode having a thickness of 100 nm was stacked. The vacuum deposition conditions at this time were room temperature, a degree of vacuum of 3 × 10 ⁻³ Pa or less, and an aluminum deposition rate of 0.3 nm / sec or less. Thus, the sample for the current-voltage characteristic evaluation of a polyimide film was produced by forming an electrode on the upper and lower sides of a polyimide film.
The sample was allowed to stand for 15 hours in an environment of 23 ° C. ± 3 ° C. and humidity of 45% ± 5%, and then the current-voltage characteristics were measured. The measurement voltage was from 0V to 100V in increments of 2V. The leakage current density of this sample at 1 MV / cm was 4.3 × 10 ⁻¹¹ A / cm ² . The polyimide film did not break down to 2 MV / cm.
FIG. 5 shows measurement results of current-voltage characteristics.

<Example 14> Insulation A sample for evaluating current-voltage characteristics was prepared in the same procedure as in Example 13 except that the composition A prepared in Synthesis Example 14 was used.
The leakage current density of this sample at 1 MV / cm was 1.7 × 10 ⁻¹⁰ A / cm ² . The polyimide film did not break down to 2 MV / cm.
FIG. 5 shows measurement results of current-voltage characteristics.

<Example 15> Insulation A sample for current-voltage evaluation was produced in the same procedure as in Example 13 except that the baking temperature was set to 230 ° C using the composition B prepared in Synthesis Example 15.
The leakage current density of this sample at 1 MV / cm was 1.2 × 10 ⁻¹⁰ A / cm ² . The polyimide film did not break down to 2 MV / cm.
FIG. 5 shows measurement results of current-voltage characteristics.

<Example 16> Insulation A sample for current-voltage evaluation was prepared in the same procedure as in Example 13 except that the firing temperature was changed to 230 ° C using the composition C prepared in Synthesis Example 16.
The leakage current density of this sample at 1 MV / cm was 3.4 × 10 ⁻¹⁰ A / cm ² . The polyimide film did not break down to 2 MV / cm.
FIG. 5 shows measurement results of current-voltage characteristics.

As shown in FIG. 3, the film made of PI-1 was an excellent insulating film in a nitrogen atmosphere (Examples 11 and 12).
Further, as shown in FIG. 4, the film made of PI-1 showed an increase in leakage current density in the atmosphere susceptible to moisture as compared with the nitrogen atmosphere, but it was used as a lower layer film for image formation. Was a level with no problem (Example 11 and Example 12).
Further, as shown in FIG. 5, the films composed of PI-4 and compositions A to C were all excellent insulating films (Examples 13 to 16).
That is, the lower layer film for image formation of the present invention was a lower layer film having sufficient insulation performance as the lower layer film for image formation.

<Example 17: Transistor characteristics>
The solution of PI-4 prepared in Synthesis Example 8 was dropped onto a glass substrate with a Cr electrode (2.5 cm square, thickness 0.7 mm) with a syringe with a 0.2 μm pore filter and applied by spin coating. Thereafter, heat treatment was performed for 5 minutes on a hot plate at 80 ° C. in the atmosphere to volatilize the organic solvent, followed by baking for 30 minutes on a hot plate at 180 ° C. to obtain a polyimide film having a thickness of about 450 nm. This polyimide film was irradiated with ultraviolet rays of ² J / cm ² through a photomask to make part of the polyimide hydrophilic. Next, an appropriate amount of the silver fine particle dispersion was dropped onto the ultraviolet irradiation part and baked on a hot plate at 180 ° C. for 60 minutes to form a source / drain electrode having a thickness of 50 nm.
A film of pentacene (manufactured by Aldrich) was formed on the silver electrode to a thickness of 70 nm by vacuum deposition. The deposition rate of pentacene was 0.05 nm / sec.

The electrical characteristics of the organic thin film transistor obtained as described above were evaluated by measuring the change of the drain current with respect to the gate voltage.
Specifically, the source-drain voltage (V _D ) is set to −80 V, the gate voltage (V _G ) is changed in steps of 2 V from +20 V to −80 V, and the voltage is held for 1 second until the current is sufficiently stabilized at each voltage. This value was recorded as a measured value of the drain current, and this operation was repeated 5 times. The measurement was performed in a nitrogen atmosphere using a semiconductor parameter analyzer HP4156C (manufactured by Agilent Technologies).

In general, the drain current _ID in a saturated state can be expressed by the following formula. That is, the mobility μ of the organic semiconductor can be obtained from the slope of the graph when the square root of the absolute value of the drain current _ID is plotted on the vertical axis and the gate voltage V _G is plotted on the horizontal axis.
_{I D = WCμ (V G -V} T) 2 / 2L
In the above equation, W is the channel width of the transistor, L is the channel length of the transistor, C is the capacitance of the gate insulating film, V _T is the threshold voltage of the transistor, and μ is the mobility. The transistor formed in this example had W = 2 mm, L = 100 μm, and C = 6.4 nF / cm ² .

When the mobility μ of pentacene was calculated based on this formula, the average was 5 × 10 ⁻² cm ² / Vs. The threshold voltage was −18 to −20 V, and the ratio of the on state to the off state (on / off ratio) was on the order of 10 ⁶ . Further, even when repeated measurement was performed, a stable characteristic was obtained without any shift in transfer characteristics (Transfer Characteristics) being observed (FIG. 6).
It was shown that the film obtained from PI-4 is excellent not only as an electrode forming film but also as a gate insulating film for an organic transistor.

<Example 18: Transistor characteristics>
An organic transistor was produced in the same manner as in Example 17 except that the composition A prepared in Synthesis Example 14 was used. The transistor formed in this example had W = 2 mm, L = 100 μm, and C = 6.5 nF / cm ² .
When the mobility μ of pentacene was calculated based on this formula, the average was 5 × 10 ⁻² cm ² / Vs. The threshold voltage was −19 to −21 V, and the ratio between the on state and the off state (on / off ratio) was on the order of 10 ⁶ . Further, even when repeated measurement was performed, no shift in the transfer characteristic was observed, and a stable characteristic was obtained (FIG. 7).
It was shown that the film obtained from the composition A is excellent not only as an electrode forming film but also as a gate insulating film for an organic transistor.

<Example 19: Transistor characteristics>
An organic transistor was fabricated in the same procedure as in Example 17 except that the amount of ultraviolet irradiation was 1 J / cm ² . The transistor formed in this example had W = 2 mm, L = 100 μm, and C = 6.4 nF / cm ² .
When the mobility μ of pentacene was calculated based on this formula, it was 3 × 10 ⁻² cm ² / Vs on average. The threshold voltage was −16 to −20 V, and the ratio between the on state and the off state (on / off ratio) was on the order of 10 ⁶ . In addition, even when repeated measurements were made, no shift in transfer characteristics was observed, and stable characteristics were obtained (FIG. 8).
It was shown that the film obtained from the composition A is excellent not only as an electrode forming film but also as a gate insulating film for an organic transistor.

The underlayer film for image form according to the present invention can realize a reduction in the exposure time required for changing the hydrophilicity / hydrophobicity, and can be expected to reduce the manufacturing cost in forming a patterning layer of a functional material such as an electrode.
In addition, anisotropy can be imparted to the film obtained from the aforementioned polyimide precursor and polyimide by irradiating polarized UV light. That is, it can also be used as an alignment treatment film of a functional material such as a liquid crystal or a semiconductor, and shortening of the manufacturing time can be expected as in the case of using it as a base film for image formation.

1 is a view showing a micrograph of a silver electrode on PI-4 produced in Example 9 (the line width of the silver electrode is 100 μm). FIG. 2 is a view showing a micrograph of the silver electrode on the composition A produced in Example 10 (the line width of the silver electrode is 100 μm). FIG. 3 is a graph showing current-voltage characteristics in a nitrogen atmosphere of a polyimide film obtained by firing a polyimide precursor (PI-1) (Examples 11 and 12). FIG. 4 is a diagram showing the current-voltage characteristics in air of a polyimide film obtained by firing a polyimide precursor (PI-1) (Examples 11 and 12). FIG. 5 is a diagram showing the current-voltage characteristics in air of the polyimide films produced in Examples 13 to 16. FIG. 6 is a graph showing the transfer characteristics of an organic transistor obtained by processing an electrode by irradiating a film obtained from PI-4 with ultraviolet rays of ² J / cm ² (Example 17). FIG. 7 is a graph showing the transfer characteristics of an organic transistor in which an electrode is processed by irradiating a film obtained from the composition A with ultraviolet rays at ² J / cm ² (Example 18). FIG. 8 is a diagram showing the transfer characteristics of an organic transistor obtained by processing an electrode by irradiating a film obtained from PI-4 with 1 J / cm ^{2 of} ultraviolet rays (Example 19).

Claims (14)

A lower layer film for image formation comprising a polyimide precursor having a repeating structure represented by the following formula (1) or a polyimide obtained by dehydrating and ring-closing the polyimide precursor.

(In the formula, A represents a tetravalent organic group, B represents a divalent structure represented by the following formula (2) or (3), and R ¹ and R ² are each independently a hydrogen atom or Represents a monovalent organic group, and n represents a natural number.)

(In the formula, X represents a single bond or a divalent aromatic group having 6 to 20 carbon atoms; Y represents a single bond, —O—, —COO—, —OCO—, —CONH—, —CH ₂ O; _-, - CH 2 COO- or _-CH 2 _CH 2 COO- represents, Z is an aliphatic hydrocarbon group which may carbon atoms 3 to 26 may be substituted with a fluorine atom, R represents each independently And represents a fluorine atom, an alkoxy group having 1 to 3 carbon atoms or an alkyl group having 1 to 3 carbon atoms, and t represents an integer of 0 to 3.) A polyimide precursor obtained by reacting a tetracarboxylic dianhydride component containing a tetracarboxylic dianhydride represented by the following formula (6) with a diamine component containing a diamine represented by the formula (7), or A lower layer film for image formation comprising a polyimide obtained by dehydrating and ring-closing the polyimide precursor.

[In the formula, A represents a tetravalent organic group, and B represents the formula (2) or the formula (3).

(In the formula, X represents a single bond or a divalent aromatic group having 6 to 20 carbon atoms; Y represents a single bond, —O—, —COO—, —OCO—, —CONH—, —CH ₂ O; _-, - CH 2 COO- or _-CH 2 _CH 2 COO- represents, Z is an aliphatic hydrocarbon group which may carbon atoms 3 to 26 may be substituted with a fluorine atom, R represents each independently Represents a fluorine atom, an alkoxy group having 1 to 3 carbon atoms or an alkyl group having 1 to 3 carbon atoms, and t represents an integer of 0 to 3). ]   The Z in the formula (2) or the formula (3) represents an aliphatic hydrocarbon group having 3 to 26 carbon atoms in which an arbitrary hydrogen atom is substituted with a fluorine atom. Underlayer film for image formation.   The underlayer film for image formation according to claim 1, wherein A represents a tetravalent organic group having an aliphatic ring or consisting only of an aliphatic group.   The underlayer film for image formation according to any one of claims 1 to 4, wherein B represents a divalent structure represented by the formula (2).   The underlayer film for image formation according to any one of claims 1 to 5, wherein X and Y each represents a single bond.   The organic transistor which has an image formation lower layer film as described in any one of Claims 1 thru | or 6. A diamine compound represented by the following formula (14) or the following formula (15).
(In the formula, X represents a single bond or a divalent aromatic group having 6 to 20 carbon atoms; Y represents a single bond, —O—, —COO—, —OCO—, —CONH—, —CH ₂ O; _-, - CH 2 COO- or _-CH 2 _CH 2 COO- represents, Z is an aliphatic hydrocarbon group having a carbon number of 3 to 26 arbitrary hydrogen atoms are substituted by fluorine atoms, R represents each Independently represents a fluorine atom, an alkoxy group having 1 to 3 carbon atoms or an alkyl group having 1 to 3 carbon atoms, and t represents an integer of 0 to 3). The polyimide obtained by dehydrating and ring-closing the polyimide precursor containing the repeating unit represented by following formula (1), or this polyimide precursor.

(In the formula, A represents a tetravalent organic group, B represents a divalent structure represented by the following formula (2a) or (3a), and R ¹ and R ² each independently represents a hydrogen atom or Represents a monovalent organic group, and n represents a natural number.)

(In the formula, X represents a single bond or a divalent aromatic group having 6 to 20 carbon atoms; Y represents a single bond, —O—, —COO—, —OCO—, —CONH—, —CH ₂ O; _-, - CH 2 COO- or _-CH 2 _CH 2 COO- represents, Z is an aliphatic hydrocarbon group having a carbon number of 3 to 26 arbitrary hydrogen atoms are substituted by fluorine atoms, R represents each Independently represents a fluorine atom, an alkoxy group having 1 to 3 carbon atoms or an alkyl group having 1 to 3 carbon atoms, and t represents an integer of 0 to 3). A polyimide precursor obtained by reacting a tetracarboxylic dianhydride component containing a tetracarboxylic dianhydride represented by the following formula (6) with a diamine component containing a diamine represented by the formula (7), or An image-forming underlayer film coating solution comprising a polyimide obtained by dehydrating and ring-closing the polyimide precursor.
(In the formula, A represents a tetravalent organic group, and B represents Formula (2) or Formula (3).
Wherein R ¹ and R ² each independently represent a hydrogen atom or a monovalent organic group, and X is a single bond or a divalent aromatic group having 6 to 20 carbon atoms. the stands, Y is a single bond, -O -, - COO -, - OCO -, - CONH -, - CH 2 O -, - CH 2 COO- or _-CH 2 _CH 2 COO- represents, Z is fluorine atom Represents an aliphatic hydrocarbon having 3 to 26 carbon atoms which may be substituted with, R independently represents a fluorine atom, an alkoxy group having 1 to 3 carbon atoms or an alkyl group having 1 to 3 carbon atoms; t represents an integer of 0 to 3. )   11. The image-forming underlayer film coating according to claim 10, wherein Z in the formula (2) or the formula (3) represents an aliphatic hydrocarbon group having 3 to 26 carbon atoms in which an arbitrary hydrogen atom is substituted with a fluorine atom. liquid.   The coating liquid for an underlayer film for image formation according to claim 10 or 11, further comprising a soluble polyimide having an imidization ratio of 80% or more.   An image-forming underlayer film obtained by baking the image-forming underlayer film coating solution according to claim 10.   The organic transistor which has a film | membrane obtained by baking the image formation lower layer film coating liquid of Claim 10 thru | or 13.