JPS6347141A - Composite article including thin-film in which polyimide precursor is cyclized partially - Google Patents

Abstract

(57) [Abstract] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to a composite article containing a thin film formed by partially ring-closing a polyimide precursor having excellent electrical insulation properties. A composite containing a thin film formed by using an amphoteric polyimide precursor modified so that it can be formed into a film by the LB method, and by the subsequent partial imidization reaction or ring-closing reaction. It concerns goods. Mainly used in the electronics field.

Conventional technology Already in the 1930s, Langmuir and Prodgett discovered that fatty acids with about 16 to 22 carbon atoms could form a monomolecular film on the water surface and accumulate it on a substrate. It has only recently begun to be carried out.

For an overview of past research, see Solid State Physics 17 (12
) 45 (1982) Th1n 5olid Fil
ms 68 No, 1 (1980) ibid, 99 N
o, 1.2.3 (1983) In5olable
monolay-ers at liquid-ga
s 1nterfaces (G, L, Ga1ns
.

Interscience Publishers,
New York, (1988), etc., the conventional Langmuir-Prodgett membrane (hereinafter referred to as rLB membrane) made of straight-chain saturated fatty acids has shortcomings in heat resistance and mechanical strength, and cannot be used in practical applications as is. The problem is that it cannot be used.

Unsaturated fatty acids, such as ω-
Polymer films made of tricosenic acid, ω-beptadenoic acid, α-octadecyl acrylic acid, unsaturated esters of fatty acids such as vinyl stearate, octadecyl acrylate, and diacetylene derivatives have been investigated, but they do not have sufficient heat resistance. It cannot be said that it is electrically superior. Regarding polymers, polyacids, polyalcohols,
Polymers with hydrophilic groups such as ethyl acrylate and polypeptides are known to have film-forming properties, but modified polymers have not been studied so far, especially as materials for Langmuir-Prodgett membranes. There is no excellent LB film material, and composite articles containing this have problems in heat resistance and mechanical strength, making it difficult to put them into practical use.

On the other hand, polyimide is used as a heat-resistant film, but it is extremely difficult to create a heat-resistant thin film with excellent electrical insulation properties of at most 1000λ or more, usually 1 μm or more and less than IoooÅ, depending on methods such as spin coding. ,
Composite articles containing thin films cannot be created.

The present invention was made to obtain a composite article containing an LB film with improved mechanical properties such as heat resistance and adhesive strength, and chemical resistance, and includes a heat-resistant thin film with excellent electrical insulation properties. The purpose is to provide composite articles.

Means for Solving the Problems The present invention was made based on the discovery that it is possible to introduce a substituent to impart hydrophobicity to a polyamic acid unit. 1986-15
General formula (1) proposed in No. 7354 etc.: (wherein R1 is 4 containing at least 2 carbon atoms)
a valent group, R2 containing at least 2 carbon atoms;
The valent groups R3, R4, R5 and R6 are all monovalent aliphatic groups having 1 to 30 carbon atoms, monovalent cycloaliphatic groups, or bonds between an aromatic group and a fatty acid group. Monovalent groups, halogen atoms, nitro groups, amino groups,
A group substituted with a cyano group, a methoxy group, an acetoxy group, or a hydrogen atom, and at least one, preferably two of R3, R4, R5 and R6 are the above-mentioned groups having 1 to 11 carbon atoms or a hydrogen atom. This is accomplished by accumulating an amphoteric polyimide precursor having a repeating unit represented by (not shown) on a substrate by the Langmuir-Prodgett method, followed by a partial imidization reaction.

The amphoteric polyimide precursor for forming the polyimide thin film of the present invention has a number average molecular weight of 2.000 to 300,000 and has a repeating unit represented by the formula (1), for example.
0. Number average molecular weight is 2,000 to 300,
If it is out of the range of 000, there is a tendency that the strength of the film produced is too low or the viscosity is too high, making it difficult to produce the film.

R1 in the general formula (1) is a tetravalent group containing at least 2 carbon atoms, preferably 5 to 20 carbon atoms, and may be an aromatic group, or a cycloaliphatic group. It may be a group in which an aromatic group and an aliphatic group are bonded, and furthermore, these groups may be an aliphatic group having 1 to 30 carbon atoms or a cycloaliphatic group. Or a group in which an aromatic group and an aliphatic group are bonded together, or these groups are monovalent groups such as a halogen atom, a nitro group, an amino group, a cyano group, a methoxy group, or an acetoxy group; The group is -0-, -COO-, -Nl+CO-, -C0-,
It may also be a group substituted with a group bonded to -5-, -C5S-, -NIIC5-, -C5-, etc. to form a derivative. However, it is preferable from the viewpoint of heat resistance, chemical resistance, mechanical properties, etc., when R1 is a group characterized by penzenoic unsaturation having at least 6 carbon atoms.

Specific examples of R1 as described above include, for example.

The term "benzenoid unsaturation" as used herein is a term used in contrast to a quinoid structure regarding the structure of a carbocyclic compound, and refers to a structure having the same shape as a carbocyclic ring contained in ordinary aromatic compounds.

In the four bonds of R', that is, the repeating unit represented by formula (1), o 0 R3-0-C-1-C-0-R', -N-C-1-C-N- There is no particular limitation on the position of the hand where R2- is bonded to R'OOR', but if two of each of the four bonding hands are present on two adjacent carbon atoms constituting R1, it is amphoteric. It is preferable because a 5-membered ring is easily formed when a film formed using a polyimide precursor is polyimidized, making it easy to imidize.

Preferred specific examples of the above-mentioned R1 include, for example, Examples include. Also Examples include. Also is also preferable.

R2 in general formula (1) is a divalent group containing at least two carbon atoms, and may be an aromatic group, an aliphatic group, or a cycloaliphatic group. It may be a group in which an aromatic group and an aliphatic group are bonded, and furthermore, these divalent groups may have 1 to 30 carbon atoms.
an aliphatic group, a cycloaliphatic group, or a group in which an aromatic group and an aliphatic group are bonded, those groups are halogen atoms,
Monovalent groups such as nitro group, amino group, cyano group, methoxy group, acetoxy group, or these monovalent groups,
-0-, -Coo-, -NHC(1-, -GO-, -
It may be a group substituted with a group bonded to 5-, -C5S-, -NHC5-, -C5-, etc. However, R2
is a group characterized by benzenoid unsaturation having at least 6 carbon atoms, which is preferable from the viewpoint of heat resistance, chemical resistance, mechanical properties, etc.

As a specific example of the above R2, R9 is CH8 (CH2)m (m=an integer of 1 to 3), -C=,
.

CH3 F3 -C-, -0-, -Co-, -3-. -5o2-.

F3 RIOR1゜ -N-, -5t-, -0-5i-0-.

RIORIOR11 R Kano RIO -o-p-o-, -p- RI0 and Rl 1 are both alkyl or aryl groups having 1 to 30 carbon atoms -(cH2)p (p -2 to 10), -(C
)12) 4-C-(CH2)2-.

CHs CH3-
(C)I2)3- C-(C)12)3-, -(C
1(2) -C-(CH2)3-1+
1CHs
C1(3C)130-(CH2)toe)I-CH3,-(CH2)3-
C-(CI(2)2-+1cTo)sO(CH2
)2 0 (C)+2)3-.

CHs CHs CHs
CH3II ll -CH2-C(CH2)2C-CH2-, -CH2C(
CI(2)2C-C)+2-.

CH,CH3-(CHz)s-Si-OSi-(CH2)3-C
H3CH3 CH3CH3 -(CLL-St -0-5i-(CH2)4-CH3
CH3 CeHs CaHs -(CI2)3- St -0-5i-(CH2)3-
CaHa Cat (s CH3CHs n is 2 to 15, etc., and preferred specific examples of R2 as described above include (wherein R9 is -(CL)m (m = an integer of t to 3)).

CH! I CF3 -c-9-c-, -o-, -co-.

CH, CF3 -3-, -3o2-, -NR"-.

RIORIG -5t-, -0-5i-0-.

Examples include RIORIO I -o-p-o-, -p- (R10 and R11 are both alkyl or aryl groups having 1 to 30 carbon atoms).

R3, R4, R5, and R6 in general formula (1) all have 1 to 30 carbon atoms, preferably 1 to 22 carbon atoms.
a valent aliphatic group, a monovalent cycloaliphatic group, a monovalent group combining an aromatic group and an aliphatic group, these groups are halogen atoms, nitro groups, amino groups, cyano groups, methoxy group,
A hydrogen atom or a group substituted with an acetoxy group or the like to become a derivative of those groups. In addition, R3, R4, R5 and R6 in formula (1) all impart hydrophobicity to the polyamic acid unit represented by general formula (8): (wherein R1, R2 are the same as above) and stabilize it. It is a group introduced in order to obtain a condensed film, and at least one, preferably two of R3, R4, R5, and R6 have a carbon atom number of 1 to 1.
The absence of 1, preferably 1 to 15 of the above-mentioned groups or hydrogen atoms is necessary in order for a stable condensate film to be formed on the water surface and to be deposited on the substrate by the LB method.

Specific examples of R3, R4, R5, and R6 other than hydrogen atoms include, for example, CH3 (CH2), (CH3)2 CI(CI2
Serigo.

(The above n values are all 12 to 30, preferably 16 to 2.
2) etc. However, in order to achieve the purpose of the present invention, it is most desirable to use a straight chain alkyl group represented by CH+ (CI(2G-) in terms of performance and cost. Nitro groups, amino groups, cyano groups, methoxy groups, acetoxy groups, etc. are not essential.However, since fluorine atoms dramatically improve hydrophobicity compared to hydrogen atoms, it is preferable to use those containing fluorine atoms. .

Specific examples of the repeating unit of the amphoteric polyimide precursor of the present invention in which two of R3, R4, R5, and R6 are hydrogen atoms include general formula (2): (wherein, R1, R2, R3, R4 is the same as above, except that R3 and R4 are not a group having 1 to 11 carbon atoms or a hydrogen atom), or a repeating unit represented by the general formula (3): (in the formula, R1, R2, R5, R6 is the same as above, except that R5 and Ra are not a group having 1 to 11 carbon atoms or a hydrogen atom), and the like.

The repeating unit of the amphoteric polyimide precursor of the present invention has the general formula (
2) or general formula (3) are preferable because they are easy to manufacture and inexpensive.

As a specific example of the amphoteric polyimide precursor of the present invention having repeating units represented by general formulas (1) to (3), for example (as a specific example of R3 and R4 in the formula, CI+3 (C
I+2) + l-1CH3(C)+2) + 3-1
CI+3 (II:112) + 5-1CTo (C
H2) + 7-1 CHs (C1b) + 9-1
CH3 (CL) 2 Yi-1CF3 (C1h) r
s-, etc.), (Specific examples of R5 and R6 in the formula are:
CH3 (CH2) 1+-1C1h (CH2) +
3-1CH3(CI+2) + 5-1CH3(CI2
) I 7-1GHs (C1h) + 9-1CH3
(CI+2) 21-1CF3 (CH2) + s-
etc.), (Specific examples of R3 and R4 in the formula include CI1
3(CH2) 1+-1083(CH2) + 3-1
C)+3 (CI2) 1s-1CHs (Cth)
+ 7-1CL (C)12) + 9-1C)13
(CI+2) 21-1CF3(II:I2) +s-
), R5, and R6 include Cl-13-1
CH3(CH2) 2-1CH3(CH2)3-1CH
3(C1+2) 5-), (Specific examples of R3 and R4 in the formula are C)+3 (C
H2) + +-1C1b (CI42) +3-1C
H3(CH2) +5-1CH3(CH2) +7-
1C113(CH2) I 9-1CH3(CH2)
Examples include those containing repeating units such as 21-1CF3 (C)12) Is-, etc.).

In the formula, - represents isomerism. For example, and represents.

In the present invention, when (a) and (b) are independent, (a)
).

This includes cases where (b) coexists.

The amphoteric polyimide precursor of the present invention as described above is generally easily soluble in organic polar solvents such as N,N-dimethylacetamide, N,N-dimethylformamide, N,N-diethylformamide, and hexamethylphosphoramide; Soluble in mixed solvents such as polar solvents and ordinary organic solvents such as chloroform, poorly soluble in ordinary organic solvents such as benzal, ether, chloroform, acetone, methanol, etc.
It is insoluble and has characteristic absorptions of amides, carboxylic acids (and sometimes carboxylic esters) and long-chain alkyl groups in infrared absorption spectroscopy. The thermal analysis results also have some characteristics; the weight begins to decrease rapidly at about 200°C.
It completes at about 400℃. After completion, the absorption of amide, carboxylic acid (carboxylic acid ester in some cases) and long-chain alkyl group disappears, and absorption of imide ring appears.

The explanation so far has been about an amphoteric polyimide precursor having a repeating unit represented by the general formula (1), but as can be easily inferred from these, various copolymers exist.

First of all, R1 in general formula (1). R2, R3,
This is realized by at least one of R4, R5, and R6 consisting of at least two types selected from the specific examples listed above.

For example, the two pieces x and y selected as R1 represent the ratio, O<x<1.0<y<1゜x+y
=1. (The same applies hereafter) In addition, when two types are selected as 82, the above examples are just examples, and R3゜R4
, Rj R8, many examples can be written in the explanation so far.

A second and more important copolymer is realized by replacing a portion of at least one or both of R1 and Ri with a group having a different valence.

First, the group substituting a part of R1 is selected from groups other than tetravalent groups containing at least two carbon atoms, and 2- and 3-valent groups can be used, but a preferred specific example is trivalent groups, and in this case, the general formula becomes as follows.

R' (inside []X), R2, R'', R', R5,
R" is the same as above. R' (in []y) is a divalent or trivalent group containing at least two carbon atoms, respectively.

Next, the group substituting a part of R2 is selected from groups other than divalent groups containing at least two carbon atoms, and trivalent and tetravalent groups are preferable.

The general formula in these cases is as follows.

R', R2 (within []x), R3, R4, R5, R6
is the same as above. R2 (in []y) is a trivalent or tetravalent group containing at least two carbon atoms, respectively.

X is a substituent for R2, -N)IR, -CONHR(
Preferred examples include R being an alkyl group or a hydrogen atom.

Modification of amphoteric polyimide precursors by these copolymerizations is important for improving the cumulative properties of the precursors by the Langmuir-Prodgett method and for improving the physical properties of polyimide thin films obtained by imidization after accumulation on a substrate. This is one of the preferred embodiments of the invention.

Specific examples of groups substituting a portion of at least one or both of R1 and R2 are as follows.

B I Q l l O -3Q2-, -N +, -5t-, -0-St-
0-.

RIG RIG R10BIORIO -o-p-o-, -p - O0 RIG and R1+ are alkyl or aryl groups C8゜CI(3 (CH2) p- (p = 2 to 10), -
(CH2)4-C-(CH2)2-.

C) 13 CH3(C
)+2)3- C-(CH2)3-, (Clh
)-C-(C1h)3-.

c++3CH3 H30 (CH2) +. CH-CH3, -(CH2)3-C
-(CL)2゜(CL)30 (CH2)20
(CH2) 3° (R9 is the same as above) (R9 is the same as above) (nil is the same as above).

To explain the copolymer in detail, specific examples are as follows.

In addition, in the previous explanation, in the repeating unit of the precursor, at least two of R3, R4, 3%, and Re are not the above-mentioned groups having 1 to 11 carbon atoms or hydrogen atoms. If it is in the range of 30% or less of the units, - Formula (9): (wherein, R1 and R2 are the same as above, R is a monovalent aliphatic group having 1 to 11 carbon atoms, monovalent cycloaliphatic groups, monovalent groups in which aromatic groups and aliphatic groups are bonded, these groups are substituted with halogen atoms, nitro groups, amino groups, cyano groups, methoxy groups, acetoxy groups, etc. group or a hydrogen atom, and the four R's may be the same or different).

Next, a method for producing the precursor of the present invention will be explained.

The precursor of the present invention having a repeating unit represented by the general formula (1) is first prepared by - a tetracarboxylic acid dioic anhydride represented by the formula (4): % formula % (wherein R1 is the same as above) General formula (5) obtained by reacting R30H and R'OH (R3 and R4 are the same as above) with
: A compound represented by the formula % (in the formula, R1, R3, and R4 are the same as above) is produced, and thionyl is synthesized at -10°C or higher, preferably at about 1 to 40°C, in a substantially anhydrous polar solvent. chloride,
Convert it into an acid halide using phosphorus pentachloride, benzenesulfonyl chloride, etc., and then add a compound represented by formula (6): % formula % (6) (wherein R2, n%, R6 are the same as above) In this case, the reaction is carried out at -10 to +20°C, preferably 0 to +10°C, but in order to complete the reaction, the reaction may be carried out at 20°C or higher after addition.

Specific examples of the compound represented by general formula (4) include the following.

Further, as specific examples of R30H and R'OH, for example, CHsO)I, CToCt1201(, CH3(
CH2)20)1.

CH3(CH2)sOH, C1h(CH2)50H, C
H3(CH2)tOH.

CH3(CI(2)90H, CH8(C)I2)++O
H, C) Is(CH2)+308°CH3(CH2)
+ sOH, CH3 (CH2) + 70)1. CH
3 (CH2) 190H.

CH3(CH2)210)1. CH3(CH2)23
0H, CF3(1;H2)+sOH.

H(CF2) 2 (CI(2) +sOH,)I (
CF2) 4 (CH2) l3ON.

F(CF2)a(lj12)20H, F(CF2)a(
C) I2) 40H.

CH3 CI((CL)+508, (CHs)sC(CI
(2) +408°CI.

etc.

Tetracarboxylic dianhydride represented by general formula (4) and R
There are no particular limitations on the reaction conditions for producing the compound represented by the general formula (5) from 3011 and R'OH. at room temperature in a solvent such as hexamethylene phosphoramide.

General conditions are adopted, such as continuing stirring for about 4 days.

To shorten the reaction time, the reaction is carried out by heating at about 100° C. for 3 hours with stirring under a nitrogen stream, and after cooling, the compound is dissolved in hexamethylene phosphoramide and then the acid halide is carried out. That is, it is preferable from the viewpoint of improving productivity.

Specific examples of polar solvents used in the acid halide conversion include hexamethylene phosphoramide, N,N-dimethylacetamide, N,N-dimethylformamide, etc. situation,
That is, thiocnyl chloride, phosphorus pentachloride, benzenesulfonyl chloride, etc. used in the acid halide conversion are not decomposed, and the acid halide reaction is carried out in a nearly quantitative manner.

If the temperature during acid halide conversion is less than -10°C, the reaction becomes heterogeneous due to freezing and solidification due to the influence of long-chain alkyl groups, which is undesirable. It can be used without particular limitation up to the temperature.

The acid halide produced in this way has the general formula (
The compound represented by 6) is reacted to produce the precursor of the present invention.

The acid halide used in this case is preferably used as it is after being produced in terms of workability and the like.

When reacting the acid halide with the compound represented by general formula (6), R3.
Since both reactants and products tend to freeze and solidify due to H4, R5, H6, etc., N, N
A solvent such as -dimethylacetamide or N,N-dimethylformamide is generally used, and the reaction temperature is -10°C to +20°C, preferably 0 to -10°C. If the reaction temperature is less than 110°C, the reaction becomes heterogeneous due to freezing and solidification, and if it exceeds +20°C, undesirable reactions are likely to occur, both of which are unfavorable.

Of course, in order to complete the reaction, the reaction may be continued at a temperature of 20° C. or higher after the addition.

Specific examples of the compound represented by formula (6) are:
For example, (a specific example of Rs and Ra in the formula is C)+3
, CH3CH2, CH3(CH2)2-1CH3(C
H2)3-1CHs(CH2)s-, CTo(lJ12
)++ , CH3(C)+2113.

C) 13(CH2)Is, CH3(CH2)+7
, C)13(CH2)19.

CI(3(CH2)21, CI(3(CH2)2)
3, CF3(CI(2)+5.

)+(CF2)2(CH2)IS, H(CF2)
4(CH2)13.

F(CF2)a(GHz)2. F(CF2)a(CH
2) 4- etc.).

The reaction ratio between the acid halide and the compound represented by the general formula (6) may be appropriately selected in order to obtain a desired molecular weight of the precursor of the present invention, but usually the molar ratio is 1.
It is 10.8-1.2. In order to obtain a polymer having a high molecular weight, it is preferable to use a stoichiometrically purified solution and a purified solvent.

- R'OH and R'01 (R3 and R4 of which are reacted with the tetracarboxylic diacid anhydride represented by formula (4))
is not a group having 1 to 11 carbon atoms or a hydrogen atom, R5 and R6 of the compound represented by formula (6) may both be hydrogen atoms, and in this case, the general formula A precursor of the present invention having a repeating unit represented by (2) is obtained.

- When both R5 and R6 of the compound represented by formula (6) are hydrogen atoms, the reactivity is good and the raw material cost is low, which is preferable. In addition, the resulting precursor is thermally stable because the carboxylic acid is an ester, and the isolation and drying operation prevents the reaction from proceeding, so it can be separated as a solid powder, and this makes it easy to purify. Become what you have.

Although the precursor of the present invention is produced by the method as explained above, - if 83 and R4 of the repeating unit represented by formula (1) are both hydrogen atoms, the above method may not be used. Directly to the tetracarboxylic diacid anhydride represented by the formula (4), - a compound represented by the formula (7): % formula % (7) (in the formula, R7 and R11 are the same as above). By reacting, a precursor of the present invention having a repeating unit represented by formula (3) is obtained.

As a specific example of the compound represented by formula (7) above,
For example, (in the formula, as a specific example of R7, RB, CH3(CH2
). -1 (.-12~30), CF3 (CJ) +5
-1H(CF2) 2 (CI42) + 5-1
tl (CF2) 4 (CL) +3-1tl (C
F2)8 (CH2) 2-1 H(CF2) a (
CH2) 4-, etc.).

The conditions for reacting the tetracarboxylic diacid anhydride represented by the general formula (4) with the compound represented by the general formula (7) are almost the same as those for producing ordinary polyamic acid. Often, for example, N,N-dimethylacetamide, N
, in a substantially anhydrous organic polar solvent such as N-dimethylformamide at a reaction temperature of 50°C or less, preferably at room temperature,
-Tetracarboxylic diacid anhydride 1 represented by formula (4)
The amount of the compound represented by general formula (7) per mole is 0.8 to
1.2 mol is reacted.

The precursor of the present invention having a repeating unit represented by the general formula (3) obtained in this way is not only easy to produce, but also has the characteristic that it can be formed into a film by the LB method and forms polyimide by heating. It is something that you have.

Further, the copolymer described above can be produced by the same method as the method for producing the amphoteric polyimide precursor.

The amphoteric polyimide precursor produced as described above may be separated and purified to be used as a film-forming material, or if necessary after production, chloroform, benzene, etc. may be added to it and used directly as a film-forming solution.

A method for forming the polyimide precursor thin film of the present invention will be described. There are the solvent casting method, the spin cord method, and the Langmuir-Prodgett method, and the Langmuir-Prodgett method was used for orientation. This method is preferable as a method for obtaining a thin film with a controlled thickness and few pinholes in units of several people.

In the case of the solvent casting method and the spin cording method, the polyimide precursor of the present invention or a mixture thereof is dissolved in a solvent such as benzene, chloroform, ethyl ether, ethyl acetate, tetrahydrofuran, dimethylformamide, N,N-dimethylacetamide, etc. It can be applied by coating it on top, and it is not possible to orient the molecules, but if the film is thick (about 1,000 layers), a high-quality film with no pinholes can be obtained.

Next, a method will be described in which the precursors described above are accumulated on a substrate by the Langmuir-Prodgett method, followed by an imidization reaction.

A method for producing an LB film using the precursor of the present invention is to spread the precursor on a water surface, compress it with a constant surface pressure to form a monomolecular film, and transfer the film onto a substrate. A certain LB
In addition to the method, methods such as the horizontal adhesion method and the rotating cylinder method (New Experimental Chemistry Course Vol. 13, Interfaces and Colloids, pp. 498-508) can be mentioned, and are particularly limited as long as they are commonly used methods. It can be used without any problem.

Generally, when a substance that forms an LB film is spread on the water surface, benzene is not dissolved in water and evaporates into the gas phase.
A solvent such as chloroform is used, but in the case of the precursor of the present invention, it is desirable to use an organic polar solvent in combination to increase solubility. Examples of such organic polar solvents include N,N-dimethylformamide, N,N-
Dimethylacetamide, N,N-diethylformamide, N,N-diethylacetamide, N,N-dimethylmethoxyacetamide, dimethylsulfoxide, N-methyl-2-pyrrolidone, pyridine, dimethylsulfone, hexamethylphosphoramide, tetramethylenesulfone ,
Examples include dimethyltetramethylene sulfone.

When benzene, chloroform, etc. are used together with an organic polar solvent, it is thought that when developed on the water surface, the benzene, chloroform, etc. will evaporate into the gas phase, and the organic polar solvent will dissolve in a large amount of water.

There is no particular limitation on the concentration of the solution used when spreading the precursor of the present invention on the water surface, but usually about 2 to 5XIO-'M is used, and in order to obtain good film forming properties, metal ion Addition and pH adjustment are not necessarily necessary, and exclusion of metal ions is considered to be an advantage when used in the electronics field.

Furthermore, when depositing the polyimide precursor of the present invention on a substrate, the use of a mixture with known Langmuir-Prodgett film compounds as we previously proposed improves the film-forming performance, which is desirable for the present invention. This is an embodiment.

The known Langmuir-Prodgett membrane compound is a compound that is also described in the literature cited above and is known in the art. In particular, compounds of the following formula consisting of a hydrocarbon group having about 16 to 22 carbon atoms and a parent wood group are preferred.

CH3(CH2) n-I Z C)+2 = CO(CH2) n-22CH3(CH
2) IC=C−C=C(CII2)IllZwhere, n
=16~22. j2+m=n-5, Z=OH, NH2,
These include C0OH, CONH2, GOOR'(R' is a lower aliphatic hydrocarbon group), and the like.

In order to improve film formability, CH3(CI(2) n −+
The one expressed by the formula Z is superior in terms of cost, but
Those containing unsaturated bonds have the characteristic that they can be polymerized by irradiation with light or radiation.

There is no particular limitation on the mixing ratio of at least one compound selected from these and the polymer compound. It is also possible to form a film by mixing two or more selected from the polyimide precursors or copolymers listed above.

The substrate on which the LB film using the precursor of the present invention is formed is not particularly limited, and may be selected depending on the purpose of the formed LB film, but when the LB film is heated and used as a polyimide, It is necessary to have good heat resistance.

Specific examples of the above-mentioned substrates include inorganic substrates such as glass, alumina, and quartz, as well as plastic substrates, inorganic substrates or plastic substrates with a thin metal film formed on them, and metal substrates. Furthermore, Si, Ga
As, TV group like ZnS, III-V group, II-
Semiconductors such as VT group, PbTiO2, BaTi03Lt
Examples include a ferroelectric substrate such as NbO, LiTaO3, or a magnetic substrate.

Of course, the metal thin film on the substrate as described above may be patterned as appropriate for the application, and Si, Ga
A substrate made of a semiconductor such as As or ZnS or a ferroelectric material may be processed in advance to form an element.

Moreover, it goes without saying that these substrates may be used after being subjected to a commonly used surface treatment.

In the case of the polyimide precursor of the present invention, glass, quartz,
Adhesive strength tends to be weak on surfaces such as Si and 5i02, and silane coupling agents, especially silanes with amino groups, epoxy groups, and alkoxy groups (for example, UCC 8-1100 and 8- 187°) or a chelate containing aluminum metal to form an aluminum oxide layer improves film forming properties and adhesive strength, and is a preferred embodiment of the present invention. Of course, the substrate may be treated with several layers of higher fatty acid metals as is done in the art.

By using the precursor of the present invention, a thin film with good heat resistance, mechanical properties, chemical resistance, and electrical insulation properties can be formed on a substrate by the LB method, and further, by converting this thin film into 8-fimid, A thin film with excellent heat resistance can be obtained.

There is no particular limitation on the imidization method, but 300~
Heating is generally performed at a temperature of around 400° C., and laser light or the like may also be used. Of course, acetic anhydride and pyridine used in the imidization of polyamic acid may be used, or they may be used in combination with a thermal reaction. For example, in the case of a repeating unit represented by formula (2), the following reaction occurs, and in the case of a repeating unit represented by formula (3), the following reaction occurs to form a polyimide. Of course-
Also in the case of the polyamic acid unit represented by formula (8), H
2O is produced and becomes a polyimide, but in this case it cannot be used as a material for an LB film.

Further, when at least one or both of nl and u2 is partially replaced with a group having a different valence, the following reaction occurs under the same conditions as the imidization reaction.

+ xR30H+ xR'OH+ xR'
OH+ xR'0H (X=CONH2) + R30H+ R'OH (X=CONH2) + R30H+ R'OH Particularly in the latter two examples, a skeleton with high heat resistance is introduced, so they are preferable for improving heat resistance.

When the above imidization and ring-closing reactions occur, the group introduced for hydrophobization is eliminated as alcohol, but this eliminated alcohol is heated at a temperature of around 300° to 400° under a gas flow if necessary. Since the polyimide film can be dispersed by placing it in a vacuum or by placing it in a vacuum, it is possible to obtain a polyimide thin film that is extremely heat resistant and has good electrical insulation properties.

In addition, among the known Langmuir-Prodgett film compounds used to improve film forming properties, those that can be dispersed under the conditions of imidization and other ring-closing reactions are selected from the examples listed above. This makes it possible to obtain a polyimide thin film that is extremely heat resistant and has good electrical insulation properties.

Further intensive study revealed that the amphoteric polyimide precursor was accumulated on the substrate by the Langmuir-Prodgett method, and then imidized (ring-closed) under milder conditions than completely imidized (ring-closed). The partially ring-closed polyimide thin film produced by ring-closing) has heat resistance of over 200℃, excellent chemical resistance, good mechanical properties, excellent electrical insulation, and It is a very thin film of less than 2,000 Å, and can accommodate 5,000, 2,000, or 10 to 1,000 people if desired.
This means that it has the characteristic that it can be done by humans as well.

The term "partial imidization (ring closure)" in the present invention includes an imidization rate of more than 0% and less than 100%, but from the standpoint of heat resistance, imidization obtained by imidization at 200'e The ratio is preferably about 40% or more and less than 100%.

As shown in the reference example, it is clear from the area-time curve that the amphoteric polyimide precursor can form an ideal Y-shaped film even by the Langmuir-Prodgett method (vertical method).
Based on the linearity of the plot (reciprocal of capacitance) vs. cumulative film number and X-ray diffraction data, L
It is suggested that the layered structure expected for the B film exists. It is also clear that the thin film of this precursor has excellent controllability of film thickness, as well as good heat resistance, dielectric properties, and electrical insulation properties.

Next, a polyimide thin film made by partially imidizing (ring-closing) this precursor thin film will be described. It is clear from the examples that this polyimide thin film has excellent heat resistance. It has excellent film thickness control even after
The thickness of the partially closed polyimide thin film can be controlled by the cumulative number of amphoteric polyimide precursors, and the existence of a layered structure is presumed, and this partially closed polyimide thin film has good dielectric and electrical properties. It has been revealed that it has insulating properties. The partially ring-closed polyimide thin film has particularly excellent electrical insulation and dielectric properties because long-chain alkyl groups remain.

In particular, it has been revealed that, according to the present invention, even a partially ring-closed polyimide thin film of 1000 Å or less can have a dielectric breakdown strength of 1×10 6 v/Cm or more. Although it is possible to create a film with good physical properties of about 10,000 by this method, considering the cost of forming the LB film, a thin film is cheaper, and in terms of application, it is possible to create a thin film that cannot be achieved with other methods. interested in. That is, films with a thickness of 2000 Å or less, or even 1000 Å or less, or several hundred, 50 to 100
Although there are new and interesting applications for membranes with good quality,
With such a film thickness, 1. It was difficult to achieve a dielectric breakdown strength of x 106 V/cm or more.

However, it has been revealed that the method of the present invention makes it possible to realize a polyimide thin film having a dielectric breakdown strength of 1 x 106 V/cm or more, which is sufficiently usable in the electronics field. In particular, for thin films with a thickness of about 50 to several hundred particles, a unique film thickness effect, such as a tunnel effect, is expected, and many interesting applications using this effect are possible.

The spin-coding method is a method for creating such a thin partially ring-closed polyimide film with long-chain alkyl groups, but even with a thickness of 1 μm or more, it has a high voltage of 1 x 106 V/
Achieving a dielectric breakdown strength of 1 cm or more requires extremely advanced technology, and it is difficult with current technology to create a polyimide thin film with a dielectric breakdown strength of 1 x 106 V/cm or more with a thickness of 1 μm or less. should be understood.

In addition, a partially ring-closed polyimide thin film is imidized under milder conditions than complete imidization, so it is preferably used in cases where the heat resistance of the substrate or element is not very good. can. As described above, an amphoteric polyimide precursor having a repeating unit represented by the general formula (1) is accumulated on a substrate by the Langmuir-Prodgett method, and a polyimide on the substrate is produced by the subsequent partial imidization reaction. The thin film has heat resistance, mechanical properties,
It has good chemical resistance and excellent electrical insulation, and is an extremely thin film of less than 10,000 Å.
It has the characteristic of being able to handle 0 people, 2000 people, and even 10 to 1000 people if desired.

In particular, it can achieve dielectric breakdown strength of 1 x 106 V/cm or more, with good physical properties of 1000 Å or less, several hundred, or 50 to 100 good grades, so it can be used in composite articles such as various electrical and electronic devices. . Among these, thin films with a thickness of about 50 to several hundred λ are expected to have a unique film thickness effect, such as a tunnel effect, and many interesting electrical and electronic devices using this effect will become possible.

Next, the composite article of the present invention will be described.

The thin films described above have excellent heat resistance, chemical resistance, and mechanical properties, and can be used in a wide range of fields such as electronics, energy conversion, and material separation by taking advantage of the characteristics that they are extremely thin films.

First, we will discuss electrical and electronic devices, which are composite articles in the electronics field that take advantage of conductivity, photoconductivity, optical properties, insulation, thermal properties, and chemical reactivity.

The first important electric/electronic device containing the thin film of the present invention is a device with a metal/insulating film/semiconductor structure (hereinafter referred to as MrS), which is the basic structure of planar electronic devices and integrated circuits.

1 to 7 are representative schematic diagrams. In FIG. 1, a thin film of the present invention is formed as an insulating film on a semiconductor substrate, and a metal electrode is provided thereon. St.

Group II raw conductors such as Ge, GaAs, and GaP III-
V group raw conductor, CdTe, CdS, ZnS, Zn5e, C
By using II-Vll group ring conductors such as dHgTe, photoelectric conversion elements such as solar cells, LEDs, etc.
In addition to a light emitting element such as a photodiode, a light receiving element, and a light detecting element, various transducers such as a gas sensor and a temperature sensor can be constructed. Of course, the semiconductor of the present invention may be selected from single crystal, polycrystal, or amorphous. Although FIG. 2 is similar to FIG. 1, such electrodes are attached when two or more elements are to be formed on one substrate. With this configuration, CCD (
Charge-transfer devices such as charge-coupled devices have been created and are an interesting application.

Next, FIG. 3 shows that a semiconductor thin film, in many cases a semiconductor, is formed on an insulating substrate having electrodes (which may be transparent electrodes, or of course may be patterned), and the thin film of the present invention is formed on top of this. It has a structure with electrodes. FIG. 4 differs from FIG. 3 in that the thin film is provided between the insulating substrate side electrode and the semiconductor thin film. Semiconductor thin films are produced using molecular beam epitaxy (
MBE), metal organic chemical vapor deposition (MOCVD), atomic layer epitaxy (ALE), vapor deposition method, sputtering method, spray pyrolysis method, coating method, etc., and are produced by methods normally used for producing semiconductor thin films, but are not limited to them. .

As semiconductors, those listed above in Figures 1 and 2 can be used in the same way, and the devices produced are also the same.

In the configuration shown in Figure 4, a semiconductor thin film is formed on the thin film of the present invention, so it is not desirable if the heat during formation exceeds the heat resistance of the thin film, but in a film with a fairly high imidization rate, amorphous silicon etc. will accumulate sufficiently. It is possible, and as low-temperature formation technology for other semiconductors is progressing, many semiconductors will be able to be used in the future.

The most important device structure of the Ml5 structure device is a so-called field effect transistor (FILr) structure, typically shown in FIGS. 5 and 6, in which the channel current is controlled and driven by a gate electrode. The difference is that FIG. 5 uses a semiconductor substrate, whereas FIG. 6 uses a semiconductor thin film formed on an insulating substrate in most cases.

MISFET is one of the basic types of devices, and various devices can be made using it. If fabricated on a large-area substrate, thin-film transistors can be used to drive a liquid crystal display, and if the degree of integration is increased, an integrated circuit can be constructed.

Another interesting application is the structure shown in Figures 5 and 6 in which the gate electrode is removed and an ion-sensitive FET (I 5FET) is created by adding an insulating film or a film that is sensitive to ions, gases, or active substances in conjunction with it. and gas sensitive EE
T (II: hemF ET ) Immune FET (IMFE
T), an enzyme FET (ENFET) can be constructed.

The operating principle can be explained by the electric field effect caused by the interaction of ions or gaseous active substances with the surface of the gate insulating film, but when using a thin film like the one of the present invention, conventional This is advantageous compared to organic matter. In particular, in thin films with long-chain alkyl groups remaining, the interaction between the alkyl group (hydrophobic) portion and the hydrophobic portion of the protein can be utilized.

FIG. 7 shows an example of an 15FET, which has a structure in which a semiconductor film is formed on a quartz substrate as shown in the figure, and an insulating film and an ion-sensitive film are provided thereon. The thin film of the present invention can be used as this insulating film.

The preferred embodiment of the present invention is when compound semiconductors such as III-V and +1'-Vl group semiconductors, in which it is difficult to form good insulating films by methods such as oxidation, are used as semiconductors when configuring devices of MIS structure. mode, and Ga
In the case of As, when forming an FET, Metal-5 semiconductor FET is used due to the above problems.
(MESFET), but MIS
Improved performance is expected by changing the structure.

Constructing a MIS integrated circuit using GaAs not only has the effect of lowering the driving voltage, but also reduces carriers in the GaAs semiconductor.
High-speed integrated circuits (HEMTs) that take advantage of high mobility can be created in a very simple manner.

The second important electric/electronic device containing the thin film of the present invention is a device with a metal/insulating film/metal (hereinafter referred to as MIM) structure.

8 to 10 are schematic diagrams. An insulating substrate or a semiconductor substrate is used, and a metal, an insulating film, and a metal are formed on the substrate in this order.

Figure 8 shows the structure of a capacitor, which can be used as a humidity sensor by tracking changes in capacitance due to humidity. Also, with this structure, a transistor with an MIM structure can be made.

A thermionic transistor can be constructed as shown in FIG.

By forming a capacitor on a semiconductor or semiconductor device as shown in FIG. 10, it can be used as a capacitor for a VLSI memory cell.

With the configuration shown in FIG. 10, it is also possible to create a type of device in which hot electrons are injected into a semiconductor.

Furthermore, it is also possible to create a Josephson junction (JJ) device by using an electromotive conductor such as Nb instead of metal.

The electrical/electronic device including the third thin film is a device with an insulating film/metal structure (1M structure), and is schematically shown in FIG. The simplest method is obtained by forming an insulating film on a metal to form the thin film of the present invention.

One application is as a liquid crystal alignment film, which is obtained by forming the thin film of the invention on a patterned transparent electrode, usually ITO.

In the next application, by forming the thin film of the present invention on two independent electrodes in Figures 12 and 13, it can be used as a sensor for humidity, gas, etc.

The electrical/electronic devices containing the thin film of the present invention have been described above, but other application examples can be found in the above-mentioned documents, especially P,
Review of S. Vincett, G. G. Roberts (
Thin 5 solid Flims 68135-13
7 (1980).

For other semiconductor devices and compound semiconductor devices, please contact E, S, Yang, Fund.
mental of Sem1 conductor
Devices MaGraw-11i11, 1978
Reference may be made to Compound Semiconductor Device [I] [+1] Industry Research Group (1984) edited by Imai et al.

Next, we will discuss composite articles other than electrical/electronic devices.

Recording methods are increasingly being adopted in which a thin film containing a dye or an inorganic thin film such as TeOx undergoes bit formation or phase change, and the change is optically read out at 0.1. The thin film of the present invention causes a reaction with light, heat, especially laser light commonly used in optical recording, and the thickness of the thin film changes to form bits.This reaction also changes the refractive index of the thin film. This suggests that optical recording using this method is possible.

It is clear from the above explanation that the thin film of the present invention is reactive to heat, and this reactivity can be used to create partially thermally closed parts and non-ring-closed parts, and It can be patterned by removing it with a solvent. The remaining portion can be used as a resist film because it has excellent heat resistance, mechanical strength, and chemical resistance.

In addition, it can also be used as a cladding material for Unibu guides or as an optical circuit component.

An optical circuit can also be formed by patterning using the method described for resist. In the case of the thin film of the present invention, the refractive index can be adjusted by accurately controlling the thickness and changing the compound. This is an important requirement for optical circuit components.

The mixture of the present invention may be suitable as a protective coating material in all fields. By using it instead, various functionalities can be expressed, and there are many possible uses for this. For example, photoelectric conversion elements and biosensors can be created by creating films containing dyes and enzymes.

It is also conceivable that this thin film could be used in the field of substance separation.

Recently, there have been many attempts to use thin films with fine pores formed on porous film substrates for material separation.

If necessary, the thin film of the present invention can be prepared under conditions that preserve known Langmuir film materials, and then a partial ring-closing reaction can be performed to form a thin film with fine pores.

For example, a compound having a polyimide precursor structure is formed on a porous polyimide film in the presence of stearyl alcohol if necessary, and then imidized at a temperature of about 200°C to partially form polyimide with fine pores. thin films can be made on porous polyimide films.

<Production of partially imidized amphoteric polyimide precursor thin film> Next, a method for forming an imide precursor film, a thin film, and a composite article containing the same will be described based on Examples.

Reference example 1 Pyromellitic dianhydride 2.18g (0.01 mol)
and 5.40 g (0.02 mol) of stearyl alcohol in a flask under dry nitrogen gas at about 100°C.
Allowed time to react.

The obtained reaction product was added to 40 cc of hexamethylene phosphamide.
Thionyl chloride was dissolved in 2. and cooled to 0-5°C.
38 g was added dropwise at about 5°C, and after the dropwise addition, the temperature was maintained at about 5°C for 1 hour to complete the reaction.

After that, 2 g (0.01 mol) of diaminodiphenyl ether dissolved in 50 cc of dimethylacetamide was added to
The mixture was added dropwise at 5° C., and the reaction was allowed to proceed for about 1 hour after the addition, and then the reaction solution was poured into 600 cc of distilled water to precipitate a reaction product. The precipitate was filtered and dried under reduced pressure at about 40°C to obtain about 9 g of pale yellow powder.

The obtained powder was subjected to IR spectrum analysis and thermal analysis (T
GA-DTA), the molecular weight was measured by GPC.

The 14th IR spectrum measured by the Or disc method was used for IR spectrum analysis.
As shown in the figure. The IR spectrum shows characteristic absorptions of ester, amide (2) absorption band, II absorption band, III absorption band, alkyl chain and ether.

Thermal analysis (TGA-DTA) RTG-DTA (H) type manufactured by Rigaku Corporation, full scale TGA 10 mg, DTA 100 μV.

Temperature: 1000°C, heating rate: 10°C/min, nitrogen flow (30°C)
Figure 15 shows the results measured in ml/win).

TGA has inflection points at 271, 318, 396, and 592°C, and DTA has a characteristic peak around 657°C.

In addition, Fig. 16 shows that the obtained precursor was heated to 400°C by 10°C.
The results are shown when the temperature was raised at a rate of /min, kept at 400°C for 1 hour, returned to room temperature, and then raised to 1000°C at a rate of 10°C/min.

By keeping it at 400° C. for 1 hour, the weight almost reaches a constant weight, and the polyimidization reaction is completed. Even when this was returned to room temperature and heated again, the weight did not change until it exceeded 450°C, which was 584°C, which is the same as the thermal decomposition temperature of polyimide film.
It is clear that thermal decomposition begins at , and that a film with the same heat resistance as polyimide film can be obtained by terminating the polyimidization reaction.

In addition, Fig. 17 shows the obtained precursor at 200°C, 250°C,
This is the TGA when the temperature was raised to 300°C and 350°C at a rate of 10°C/win, and each temperature was maintained for 1 hour.

A weight loss corresponding to the imidization temperature occurs, approximately 45%, 6
It is suggested that imidization is 3%, 77%, and 98.6%. I of the product obtained after further partial imidization
R spectrum analysis shows that the imidization reaction occurs in response to the imidization temperature at 1720cl',
The degree of appearance of imide ring characteristic absorption such as 1780 cm-',
This became clear from the degree of disappearance of absorption of long-chain alkyl groups from 3000 to 2800 cm-'. Figure 18 shows 1 at 200℃.
IR spectrum of time imidized product.

Molecular weight measurement by GPC GPC measured with N,N-dimethylacetamide solvent
The number average molecular weight calculated by comparing the results with polystyrene standard samples was about 5o, ooo.

Reference Example Chloroform obtained by distilling the product 55.1B of Reference Example 1/
A spreading solution for LB membrane was prepared by dissolving it in a mixed solution of dimethylacetamide-8/2 (volume ratio) to make a 25 ml solution.

Using the obtained developing solution, place the surface pressure π on double distilled water at 20°C.
When the relationship between this and the area per repeating unit (Unit) was measured, the results shown in FIG. 19 were obtained. 75 people 2
The surface pressure rose rapidly from about /unit, and a good condensed film was formed. The ultimate area was 60 persons/unit, and the collapse pressure was 55 dyne/cm, which is a very high value for a polymer membrane.

Furthermore, even when the membrane was held on the water surface with a surface pressure of 256 yne/cm, no decrease in area was observed for 2 hours.
The film was stable.

Next, the surface pressure of the membrane on the water surface was set to 25 dyne/c at 20°C.
90 layers were accumulated on a glass substrate or a CaF2 plate by the LB method at a cumulative speed of 10 mm/min.

When the film formed on the CaF2 plate was analyzed by FT-ART-IR, a spectrum as shown in Figure 20 was obtained, which was the cumulative film of the compound obtained in Reference Example 1, and from the area-hour curve, it was determined that it was a Y-type film. It was confirmed that there is. Although the aqueous layer used in this example does not contain (d" ions, etc.), the X-ray diffraction analysis of a cumulative film of 90 layers shows only one peak at 20 = 4.65°. Observed.

Bragg diffraction conditions nλ=2dsinθ, n-3, λ
= 1.5418 people, d (thickness of one layer) is 2
It is calculated to be 8.5 people, which is almost the same as the value when the long chain alkyl group is vertically erected in the amphoteric polyimide precursor.

Further, by heating the cumulative film at 400°C for 1 hour, α, β-unsaturated 5-membered ring imide is produced.
-ATR-IR analysis 1790 cm-', 17
It was confirmed by the peak at 10 cm-'.

Furthermore, when the product of Reference Example 1 is heated at 400°C for 1 hour, 5
It has been confirmed by infrared absorption spectrum analysis that a reduction of 8% (weight %, the same applies hereinafter) occurs and imidization occurs. The above weight reduction was in good agreement with the calculated value of 58.7% when stearyl alcohol disappears by imidization.

Comparative Example 1 A polyimide precursor was synthesized in the same manner as in Reference Example 1 using n-decyl alcohol (n-C+ol(2+OH)) instead of stearyl alcohol.

This polyimide precursor was analyzed by IR spectrum analysis, thermal analysis,
As a result of molecular weight measurement by GPC, it was found that the polyimide precursor had the same characteristics as the polyimide precursor of Example 1, but the measurement results of the surface pressure area curve were as shown in Figure 21, and there was only a liquid expanding phase and a condensed phase. did not indicate the existence of Therefore, it has become clear that the length using an alkyl group having 10 carbon atoms is too short to obtain a safe condensed phase.

Reference Examples 3 to 5 In the same manner as in Reference Example 1, instead of stearyl alcohol, polyimide precursors were synthesized using lauryl alcohol, myristyl alcohol, and cetyl alcohol having 12.14.16 carbon atoms.Reference Examples 3 to 5, respectively. ).

When an alcohol with 12.14 carbon atoms was used, the behavior was intermediate between alcohols with 10 and 18 carbon atoms, but when the aqueous phase was heated to about 5° C., a stable condensed phase was obtained.

It has been revealed that when an alcohol with 16 carbon atoms is used, a stable condensation film is formed, similar to that using an alcohol with 18 carbon atoms.

Reference Example 6 10.91 g of pyromellitic dianhydride and 27.05 g of stearyl alcohol were reacted at 120°C for 3 hours, and the product was recrystallized from 200 ml of ethanol to give a melting point of 133 to 1.
Distearyl pyromellitate at 37°C was obtained.

60cc of this distearyl pyromellitate 3.79g
The mixture was dissolved in hexamethylene phosphamide and cooled to 5°C, and 1.19 g of thionyl chloride was added dropwise at about 5°C, and the reaction was maintained for about 1 hour after the dropwise addition to complete the reaction. Thereafter, 1.2 g of diaminodiphenyl ether dissolved in 30 cc of dimethylacetamide was added dropwise at about 10°C, the reaction temperature was raised to about 20°C, the reaction was allowed to proceed for 2 hours, and the reaction product was precipitated by pouring into 400 cc of ethanol. Ta. The precipitate was filtered through the mouth and dried at 40°C to obtain about 3.4 g of pale yellow powder.

IR spectrum analysis, thermal analysis (TGA-DTA), GP
When the molecular weight was measured using C, the following results were obtained.

The IR chart taken using the Br disk method for IR spectrum analysis is shown in FIG. 22, and characteristic absorptions of ester, amide I, II, III, alkyl chain, and ether were observed.

Thermal analysis (T'GA-DTA) RTG-DTA (H) type manufactured by Rigaku Denki, full scale TGA 10n+g, DTA 100 μV, temperature 1000℃, heating rate 10℃/min, nitrogen flow (30m
The results measured in 1/m1n) are shown in FIG. 203.270.354.403.58 for TGA
Although there is an inflection point at 0°C, there is no characteristic peak in DTA.

Molecular weight measurement by GPC Chloroform, N,N-dimethylacetamide (8:2
) The number average molecular weight measured in the mixed solvent was about 15,000 in terms of polystyrene.

Reference Example 7 55.1 mg of the product of Reference Example 6 was dissolved in a mixed solution of distilled chloroform/dimethylacetamide = 8/2 (volume ratio) to prepare 25 ml of a developing solution for LB membrane.

When the relationship between surface pressure and area per repeating unit was measured at 20° C. over double-distilled water, the results shown in FIG. 24 were obtained. The surface pressure rose rapidly from about 65 persons/unit, and a good condensed film was formed. The ultimate area is about 55
person'/unit, and the collapse pressure is 45 dyne/c.
It was m. (Figure 24-A) Mix the same volume of stearyl alcohol solution with the same molar concentration as the above solution,
When the surface pressure area curve was evaluated in such a way that the total number of repeating units of the product of Example 1 and the number of molecules of stearyl alcohol was equal to that shown in FIG. 24-A, the results shown in B were obtained. The addition of stearyl alcohol made the rise of the curve even steeper, and the collapse pressure also increased to about 606 yne/
cm, indicating that the film is stabilized.

The accumulation on the glass substrate on which aluminum was vapor-deposited (glass substrate treated with silane coupling agent A-1100 or A-187) was Y-type regardless of whether or not stearyl alcohol was added, and a good accumulated film was obtained. It was done.

Furthermore, 1 of the product of Reference Example 6 and stearyl alcohol:
1 (molar ratio) of the mixture on a germanium substrate,
When heated at 400℃ for 1 hour under nitrogen flow, FT-AT
Disappearance of stearyl group and 1790.17 by R-IR method
The appearance of a 10 cm-' 5-membered ring imide was observed.

Reference Example 8 Similar to Reference Example 7, the surface pressure area curve was evaluated using stearic acid, ω-hebutadenoic acid, and octadecane instead of stearyl alcohol, and in each case, the curve was the same as in the case of stearyl alcohol. It was found that the rise in temperature became steeper and the collapse pressure also increased.

The collapse pressures of stearic acid and ω-hebutadenoic acid were almost the same as stearyl alcohol and superior to octadecane.

Further, a film to which stearic acid, ω-heptadenoic acid, and octadecane were added was accumulated in a Y-shape on a glass substrate on which aluminum was deposited, and a good accumulated film was obtained.

Reference Example 9 Using the compound of Reference Example 1, 1.3, 5,
A cumulative film of 7.9 layers of amphoteric polyimide precursor was prepared.

After drying this in a desiccator for one night, an aluminum electrode of 0.1 mmrl was deposited perpendicularly to the aluminum electrode, and the capacitance was measured at a frequency of 1 and l+z at room temperature.

FIG. 25 is a plot of the reciprocal of capacitance versus the cumulative number of films. The bars indicate the dispersion of the 10 pieces of data. For a single layer film, the loss factor is 0.20
Although to some extent, films with five or more layers had a value of 0.02 or less, showing good performance.

Reference Example 10 Using a mixture of the compound of Reference Example 6 and stearyl alcohol at a ratio of 1:1 (dry ratio), 11,21,31.41.51
A cumulative film of layers was created. 0.5 on a glass substrate treated with silane coupling agent A-1100 (1%)
A vacuum-deposited aluminum electrode with a thickness of 1 mm was used.

After accumulation, it was dried overnight, treated at 400°C for 1 hour under nitrogen flow, and then 0.1 m perpendicular to the aluminum electrode.
An aluminum electrode with a width of m was deposited and the capacitance was measured at room temperature at a frequency of lK11z.

FIG. 26 is a plot of the reciprocal of capacitance versus the cumulative number of films. The bars indicate variations in 10 pieces of data. The loss coefficient was about 0.02 in all cases.

Reference example 11 Same as reference example 10, 11, 21, 31° 41.5
A cumulative film of 1,101,151 layers was made and heated at 400°C under a nitrogen stream for 1 hour, resulting in a device area of 0.18 crn'.
An aluminum/polyimide thin film/aluminum device was created.

The thickness of each polyimide thin film is approximately 50.100.1
．． 50,200,250,500,700 people. 1 x 1 for each of these 10 samples
06V/cm, 2. 3. 4. 5x 106V
An electric field of /cm was applied, but no dielectric breakdown occurred. This revealed that it had a dielectric breakdown strength of 1 x 106 V/cm or more.

Reference Example 12 In the same manner as Reference Example 10, about 100 people made a polyimide thin film.
An aluminum/polyimide thin film/aluminum device with a device area of 0.18 crn' was prepared and its IV characteristics were evaluated.

The results are shown in Figure 27.28.

Ohmic 4 in electric fields up to 0.5X 106V/cm
It was found that the conductivity was found to be high, and that the conductivity above 1nIccV3/42 was observed. Also Figure 12.13
As is clear from the above, the polyimide thin film of the present invention has a voltage of 106V.
It has become clear that the data obtained by repeated measurements after the experiment shown in FIG. 13 largely reproduces the results of the first experiment, indicating that it can withstand not only an electric field of 10'V/cm but also an electric field of 10'V/cm.

Example 1 A cumulative film of 41 layers of 11, 21, 31° was prepared in the same manner as in Reference Example 10, and heated at 200° C. for 1 hour in a nitrogen stream to partially imidize aluminum 1 with a device area of 0.18 crn'. A polyimide thin film aluminum device was created.

The capacitance of this device was measured at room temperature at a frequency of I KHz.

FIG. 29 is a plot of the reciprocal of capacitance versus the cumulative number of films. The bars indicate variations in 10 pieces of data, and the loss coefficient was about 0.01.

In addition, these thin films were charged with 1.2, 3, 4, 5xlO6V/c1
Although an electric field of 11 was applied, no dielectric breakdown occurred.

Effects of the Invention According to the present invention, a polymer compound modified so that it can be formed into a film by the LB film method forms a more stable film on the water surface, can be accumulated well on the substrate, and is then subjected to an imidization reaction. By doing this, we can create products with extremely good heat resistance, good chemical resistance, good mechanical properties, and a dielectric breakdown strength of 106 V/cm or more, which is generally difficult to create, i.e., less than io, ooo Å, and if desired, from 10 to 1000 people. A variety of composite articles can be obtained that include ultrathin films of.

[Brief explanation of drawings]

FIGS. 1-7 are schematic diagrams of typical Mis structure devices, FIGS. 8-10 are MIM structures, and FIGS. 11-13 are 1M structures. Figure 14 is the IR spectrum of the precursor obtained in Reference Example 1, Figure 15 is a graph showing the thermogravimetric analysis (TGA-DTA) results of the precursor obtained in Reference Example 1, and Figure 16 is the reference example. The precursor obtained in 1 was heated from room temperature to 400°C,
Keep it there for 1 hour, cool to room temperature, then heat to 1000℃.
Figure 17 is a graph showing the thermogravimetric analysis (TGA-DTA) results when the temperature was raised to 200 and 250°3, respectively.
Figure 18 is a graph showing the TGA results when the temperature was raised to 350℃ and kept at that temperature for 1 hour.
This is an IR spectrum of a compound produced over time. FIG. 19 is a graph showing the results of measuring the relationship between surface pressure and area per repeating unit when the precursor obtained in Reference Example 1 is spread on the water surface according to Reference Example 2, and FIG. The spectrum showing the FT-ARTIR measurement results of the film developed above was accumulated on a CaF2 plate by the LB method, and Figure 21 shows the relationship between the surface pressure and area per repeating unit of the precursor obtained in Comparative Example 1. Graph showing the results of measuring the relationship, Figure 22 is the infrared absorption spectrum of the precursor obtained in Reference Example 6, Figure 23 is the result of thermal analysis, and Figure 24 is the precursor obtained in Reference Example 6. and the surface pressure and area curve when it is mixed with stearyl alcohol at a molar ratio of 1:1,
Figure 25 shows the reciprocal of the capacitance of the precursor cumulative film and the cumulative number of films, Figure 26 shows the reciprocal of the capacitance of the polyimide thin film after imidization plotted against the cumulative number of precursor films, and Figure 27.28 The figure shows a polyimide thin film.
Current) versus V (voltage) characteristics. FIG. 29 is a plot of the reciprocal capacitance of a thin film partially imidized at 200° C. versus the cumulative number of precursor films. Ion 7 Σ1 Tatami 1 Fig. 7 Fig. 6 Fig. 8 Fig. 9 Fig. 10 Fig. 11 Fig. 12 Fig. 13

Claims (7)

[Claims] (1) General formula (1): ▲There are mathematical formulas, chemical formulas, tables, etc.▼ (1) (In the formula, R^1 is a tetravalent group containing at least 2 carbon atoms, R^2 is at least 2 R^3, R^4, R^5 and R^6 are all monovalent aliphatic groups having 1 to 30 carbon atoms, monovalent cycloaliphatic A monovalent group in which a group group or an aromatic group and a fatty acid group are bonded, a group in which these groups are substituted with a halogen atom, a nitro group, an amino group, a cyano group, a methoxy group, an acetoxy group, or a hydrogen atom and R^3, R^4, R
At least one, preferably two of ^5 and R^6 are not the above-mentioned groups having 1 to 11 carbon atoms or hydrogen atoms), and an amphoteric polyimide precursor having a repeating unit is partially ring-closed. Composite articles containing thin films. (2) A composite comprising a thin film characterized in that a mixture of the amphoteric polyimide precursor of claim 1 and, if desired, a known Langmuir-Prodgett film compound is accumulated and partially ring-closed by the Langmuir-Prodgett method. Goods. (3) A composite article comprising the thin film of Items 1 to 2, wherein one or both of the first and second organic groups R1 and R2 is a benzenoid group having at least 6 carbons. (4) The first hydrocarbon-containing group R^3 contains an aliphatic group, a cycloaliphatic and aliphatic bonded group, an aromatic and aliphatic bonded group, or a substituted product thereof Composite article comprising the thin film of item 1 or 2. (5) 5-membered ring or 6-membered ring in which the repeating unit contains a heteroatom
A composite article comprising the thin film according to any one of Items 1 to 4, which is provided with a precursor structure that generates a membered ring. (6) The hydrocarbon-containing group R^3 has 16 to 22 carbon atoms.
A composite article comprising the thin film according to any one of items 1 to 5. (7) A composite article comprising a thin film according to any one of items 1 to 6, wherein the known Langmuir-Prodgett film compound is a compound consisting of a hydrocarbon group having 16 to 22 carbon atoms and a hydrophilic group.