JPH10212464A - Tape with heat-resistant adhesive - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain the subject product, excellent in flexibility and insulating properties without any blister, peeling, etc., of an adhesive layer even under severe environments by slitting a heat-resistant film having a specific heat- resistant adhesive layer consisting essentially of a polymide. SOLUTION: This tape is obtained by forming a thin film of a heat-resistant adhesive, consisting essentially of a polyimide having >=250kg/mm<2> elastic modulus, flexibility and further >=0.9kg/cm<2> adhesive strength measured at 180 deg.C for a laminate prepared by bonding a copper foil to a polyamide film with the adhesive and having heat resistance on a heat-resistant film and then slitting the resultant film having the adhesive layer. A soluble polyimidosiloxane comprising an aromatic tetracarboxylic acid component consisting essentially of 2,3,3',4'- biphenyltetracarboxylic dianhydride, a diaminopolysiloxane represented by the formula [R is a bivalent hydrocarbon; R1 to R4 are each a lower alkyl or phenyl; (n) is 3-60] and an aromatic diamine is preferred as the polyimide.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a tape with a heat-resistant adhesive formed by slitting a heat-resistant film having a heat-resistant adhesive layer mainly composed of a flexible polyimide.
Related to

The tape with a heat-resistant adhesive according to the present invention is capable of bonding a metal foil such as a copper foil and a heat-resistant film at a relatively low temperature, and has a laminated structure bonded with the heat-resistant adhesive. Since the adhesive layer has sufficient adhesive strength and excellent heat resistance, there is no blistering or peeling of the adhesive layer even in a high-temperature environment. For example, it can be suitably used for a coated electric conductor used in a nuclear fusion reactor, a particle accelerator and the like.

[0003]

2. Description of the Related Art Conventionally, a method of winding a tape-like polyimide film around the wire or a method of applying an adhesive to the polyimide film and winding it as an insulating coating of a linear electric conductor have been adopted. Epoxy resins, urethane resins, and the like have often been used as adhesives. However, electrical conductors manufactured using known adhesives, when exposed to high temperatures, cause blistering or peeling in the adhesive layer, or when exposed to low temperatures such as liquid nitrogen or liquid helium. In addition, there is a problem that cracks occur or the material becomes brittle, and improvement thereof has been desired.

In order to improve such disadvantages, an imide resin-based adhesive such as N, N '-(4,
4'-diphenylmethane) bismaleimide and 4,4'-
Precondensates consisting of diaminodiphenylmethane have been proposed. However, since the precondensate itself is brittle,
It is not suitable as an insulating coating for a linear electric conductor requiring flexibility. Also, for example, see JP-A-62-232.
475 and JP-A-62-235382 propose a thermosetting adhesive film formed from a resin composition obtained by mixing an aromatic polyimide obtained from benzophenonetetracarboxylic acid and an aromatic diamine with bismaleimide. However, these adhesive films are problematic in terms of practicality.

[0005]

SUMMARY OF THE INVENTION An object of the present invention is to solve the above-mentioned problems of the known adhesive, and to prevent the adhesive layer from being blistered, peeled, cracked, etc. even in a harsh environment, and to be flexible. It is an object of the present invention to provide a tape with a heat-resistant adhesive, which is excellent in insulation and insulation properties.

[0006]

According to the present invention, polyimide is used as a main component, and the polyimide film has an elastic modulus of 25%.
A laminate formed by having a heat-resistant adhesive thin film having a flexibility of 0 kg / mm or less on one or both sides of a heat-resistant film, and bonding a copper foil and a heat-resistant film with the heat-resistant adhesive. The measured adhesive strength at 180 ° C (180 °
The present invention relates to a tape with a heat-resistant adhesive obtained by slitting a heat-resistant film having a heat-resistant adhesive layer having a heat resistance of 0.9 kg / mm ² or more.

[0007]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Preferred embodiments of the present invention will be listed below.

1) A tape with a heat-resistant adhesive as described above, wherein the heat-resistant adhesive is obtained by adding a fine inorganic filler in a ratio of 0.2 to 5 parts by weight to 100 parts by weight of polyimide. 2) The tape with a heat-resistant adhesive in which a metal foil such as a copper foil is laminated on another surface of the heat-resistant adhesive layer. 3) (a) a heat-resistant adhesive comprising, as a polyimide, an aromatic tetracarboxylic acid component containing biphenyltetracarboxylic acids as a main component;

[0009]

Embedded image

(Wherein, R represents a divalent hydrocarbon residue, R ₁ , R ₂ , R ₃ and R ₄ represent a lower alkyl group or a phenyl group, and n represents an integer of 3 to 60) (B) 100 parts by weight of a soluble polyimide siloxane obtained from a diamine component consisting of 10 to 80 mol% of a diaminopolysiloxane and 20 to 90 mol% of an aromatic diamine, and (b) an epoxy compound 15- having an epoxy group.
80 parts by weight, (c) the tape with a heat-resistant adhesive, which is a heat-resistant adhesive containing an epoxy curing agent as a resin component.

The polyimide used as a main component in the present invention has an elastic modulus of 250 kg when formed into a film.
/ Mm ² or less.

The aromatic tetracarboxylic acid component that gives the soluble polyimide siloxane includes 3,3 ′,
4,4′-biphenyltetracarboxylic acid, 2,3
3 ′, 4′-biphenyltetracarboxylic acid, or biphenyltetracarboxylic acids such as dianhydrides and esterified products thereof, is added in an amount of 60 mol% or more, particularly 80-100 mol%.
The aromatic tetracarboxylic acid component contained is preferably used. Among these, 2,3,3 ', 4'-biphenyltetracarboxylic dianhydride is particularly preferable.

The aromatic tetracarboxylic acid component which can be used together with the biphenyltetracarboxylic acids includes, for example, 3,3 ', 4,4'-benzophenonetetracarboxylic acid, 3,3', 4,4 ' -Diphenyl ether tetracarboxylic acid, bis (3,4-dicarboxyphenyl) methane, 2,2-bis (3,4-dicarboxyphenyl) propane, pyromellitic acid, or their acid dianhydrides or esterified products Can be suitably mentioned.

As the diaminopolysiloxane represented by the above general formula (1), divalent carbon having two or more methylene groups having 2-6, especially 3-5 carbon atoms, or phenylene group in which R is A hydrogen residue, R ₁ -R ₄ are a methyl group,
It is preferably a lower alkyl group having 1 to 5 carbon atoms such as an ethyl group or a propyl group, or a phenyl group.
~ 60, especially about 5-20, and more preferably about 5-15. If the number of carbon atoms of R and R ₁ -R ₄ is too large, or if the number of n is too large, the reactivity may be lowered, the heat resistance may be deteriorated, the molecular weight of the obtained polyimide siloxane may be lowered, or the solubility in organic solvents may be reduced. And the compatibility with other organic compounds tends to be poor.

As specific examples of the diaminopolysiloxane represented by the general formula (1), ω, ω′-bis (2-
Aminoethyl) polydimethylsiloxane, ω, ω'-bis (3-aminopropyl) polydimethylsiloxane,
ω, ω′-bis (4-aminophenyl) polydimethylsiloxane, ω, ω′-bis (4-amino-3-methylphenyl) polydimethylsiloxane, ω, ω′-bis (3
-Aminopropyl) polydiphenylsiloxane and the like.

The aromatic diamine preferably used together with the diaminopolysiloxane is generally an aromatic diamine compound having two or more, especially 2 to 5, aromatic rings such as a benzene ring, for example, a biphenyl-based compound. Diamine compound, diphenyl ether diamine compound, benzophenone diamine compound, diphenyl sulfone diamine compound, diphenylmethane diamine compound, diphenylpropane diamine compound, diphenylthioe-
Ter-based diamine compound, bis (phenoxy) benzene-based diamine compound, bis (phenoxyphenyl) sulfone-based diamine compound, bis (phenoxy) diphenylsulfone-based diamine compound, bis (phenoxyphenyl) propane-based diamine compound, bis (phenoxyphenyl)
Propane diamine compounds and the like can be mentioned, and these can be used alone or as a mixture.

Specific examples of the aromatic diamine include:
Diphenyl ether diamine compounds such as 4,4'-diaminodiphenyl ether and 3,3'-diaminodiphenyl ether, 1,3-bis (3-diaminophenoxy) benzene, 1,4-bis ( 4-aminophenoxy)
Bis (phenoxy) benzene diamine compounds such as benzene, bis-bis [4- (4-aminophenoxy) phenyl] propane, and bis-bis (4- (3-aminophenoxy) phenyl] propane such as 2,2-bis [4- (4-aminophenoxy) phenyl] propane (Phenoxyphenyl) propane-based diamine compound, bis [4- (3-
Aromatic diamine compounds having 2 to 5 aromatic rings, such as bis (phenoxyphenyl) sulfone-based diamine compounds such as [aminophenoxy) phenyl] sulfone, can be suitably exemplified.

The diaminopolysiloxane and the aromatic diamine compound are the former in an amount of 10 to 80 mol%, preferably 15 to 80 mol%.
-70 mol%, further 20-65 mol%, the latter being 20-9
It is preferred to use 0 mol%, especially 30-85 mol%, and more preferably 35-80 mol%. If either component is too large or too small to fall outside these ranges, the elastic modulus of the polyimidesiloxane will increase and the solubility in organic solvents will decrease, which is not preferable.

The above-mentioned polyimide siloxane is produced, for example, by the following method. (a ₁ ) An aromatic tetracarboxylic acid component and a diaminopolysiloxane and a diamine component of an aromatic diamine are continuously used in an organic polar solvent at a temperature of 15 to 250 ° C. using substantially equimolar amounts.
To obtain polyimide siloxane by polymerization and imidation.

(A ₂ ) Separating the diamine component, the excess amount of the aromatic tetracarboxylic acid component and diaminopolysiloxane are polymerized and imidized in an organic polar solvent at a temperature of 15 to 250 ° C. An imidosiloxane oligomer having an acid or acid anhydride group at about 1-10 terminals is prepared, and an aromatic tetracarboxylic acid component and an excess amount of an aromatic diamine are separately prepared in an organic polar solvent at a temperature of 15 to 250 ° C. Polymerization and imidization are performed to prepare an imide oligomer having an amino group at the terminal having an average degree of polymerization of about 1-10, and then these are mixed so that the acid component and the diamine component are substantially equimolar, and the mixture is mixed at a temperature of 15- A method of reacting at 60 ° C. and further raising the temperature to 130-250 ° C. to obtain a block type polyimide siloxane.

(A ₃ ) An aromatic tetracarboxylic acid component, a diaminopolysiloxane component and an aromatic diamine component are used in substantially equimolar amounts, and are first polymerized at a temperature of 20 to 80 ° C. in an organic polar solvent to once convert polyamic acid. There is a method of obtaining polyimide siloxane by imidation after obtaining.

The organic polar solvent used in the production of the polyimide siloxane includes, for example, N, N-dimethylacetamide, N, N-diethylacetamide, N, N
Amide solvents such as -dimethylformamide, N, N-diethylformamide, N-methyl-2-pyrrolidone,
Solvents containing a sulfur atom such as dimethyl sulfoxide, diethyl sulfoxide, dimethyl sulfone, diethyl sulfone, hexamethylsulfonamide, phenol solvents such as cresol, phenol, xylenol, acetone, methanol, ethanol, ethylene glycol,
Solvents having an oxygen atom in the molecule such as dioxane and tetrahydrofuran, and other solvents such as pyridine and tetramethyl urea can be mentioned.If necessary, benzene, toluene, and aromatic hydrocarbons such as xylene can be used. Other types of organic solvents such as solvents, solvent naphtha and benzonitrile can be used in combination.

In one embodiment of the invention, the polyimide siloxane is said (a ₁₎ -
Although it may be obtained by any method such as (a ₃ ), it has as high a molecular weight as possible and a high imidation ratio, and is at least 3% by weight or more, especially about 5 to 40% by weight in the organic polar solvent. Those which can be dissolved at a concentration are preferable because an adhesive having a good bonding operation and good bonding performance can be obtained.

The above-mentioned polyimidesiloxane has an imidation ratio of preferably 90% or more, particularly preferably 95% or more, as measured by an infrared absorption spectrum analysis method. In the infrared absorption spectrum analysis, the absorption peak relating to the amide-acid bond of the polymer is substantially present. It is preferable that the imidation ratio is high so that only the absorption peak relating to the imide ring bond is not found in the above.

The above polyimide siloxane has a logarithmic viscosity (measured concentration: 0.5 g / 100 ml solvent,
Solvent: N-methyl-2-pyrrolidone, measurement temperature: 30
° C, viscometer: Cannon-Fenske viscometer)
5-4, and more preferably about 0.1-3.

Further, the above-mentioned polyimide siloxane has an elastic modulus of 250 kg / m 2 when formed into a film.
m ² or less, more preferably 0.5 to 200 kg / mm
^The thermal decomposition initiation temperature is preferably 250 ° C. or higher, particularly 300 ° C. or higher, and the secondary rearrangement temperature is preferably −10 ° C. or higher, particularly about 10 to 250 ° C.

The epoxy compound (b) preferably used in the present invention is used in an amount of 15 to 80 parts by weight, especially 20 to 100 parts by weight of the polyimide siloxane.
When the amount is too large or too small, the uncured adhesive becomes sticky and is heated to lack flexibility after lamination, or the softening point of the adhesive before lamination is high. It is preferable to set the content within the above range, since the adhesive properties after heating and laminating may be deteriorated due to excessive heat.

Examples of the other epoxy compounds include compounds having one or more epoxy groups, for example, bisphenol A or bisphenol F type epoxy resin (trade name: Epicoat 807, manufactured by Yuka Shell Co., Ltd.). 828
Phenol novolak epoxy resin, alkyl polyphenol epoxy resin (Nippon Kayaku Co., Ltd.)
RE701, RE550S, etc.), polyfunctional epoxy resin (manufactured by Sumitomo Chemical Co., Ltd., ELM-100, etc.), glycidyl ether type epoxy resin, glycidyl ester type epoxy resin, glycidylamine type epoxy resin [for example, Mitsubishi Gas Chemical Co., Ltd.] Product name: Tetrad X
Etc.] can be used alone or in combination. If the melting point of the epoxy compound is too high, the softening point of the adhesive before heating and lamination increases, so that the melting point is 90 ° C. or less, especially 0-80.
Those having a temperature of about ℃ or those which are liquid at a temperature of 30 ° C or less are preferred.

In the heat-resistant adhesive of the present invention, an epoxy curing agent may be used as the component (c). For example, curing agents such as imidazoles, tertiary amines, and triphenylphosphines; polyaddition type curing agents such as dicyandiamides, hydrazines, aromatic diamines, and phenol novolak type curing agents having a hydroxyl group; And organic peroxides. The curing agent is appropriately used together with a known curing accelerator.

The epoxy curing agent is preferably used in an amount of about 0.01 to about 60 parts by weight based on 100 parts by weight of the epoxy compound.

The above-mentioned heat-resistant adhesive preferably comprises the above-mentioned polyimidesiloxane (a), epoxy compound (b),
A predetermined amount of the epoxy curing agent (c) can be easily obtained by uniformly stirring and mixing. When mixed with an organic polar solvent, a solution composition of the heat-resistant adhesive is obtained. Examples of the organic polar solvent include organic polar solvents that can be used in obtaining the polyimide siloxane, for example, a solvent having an oxygen atom in a molecule such as dioxane and tetrahydrofuran, and N-methyl-.
Amide solvents such as 2-pyrrolidone are preferably used.

The concentration of the solution composition of the heat-resistant adhesive is as follows:
The solution viscosity is preferably 3 to 50% by weight, particularly 5 to 40% by weight, and the solution viscosity (30 ° C.) is about 0.1 to 10,000 poise, particularly about 0.2 to 5000 poise, and more preferably about 0.3 to 1000 poise. preferable.

Further, the above-mentioned solution composition may contain fine inorganic fillers such as silicon dioxide, aluminum oxide and titanium oxide. An appropriate amount of addition is 0.2-5 parts by weight based on 100 parts by weight of the polyimidesiloxane.

The heat-resistant adhesive according to the present invention is:
The softening point (temperature at which softening starts on a hot plate) of the composition containing only the uncured resin component is preferably 150 ° C or lower, particularly 140 ° C or lower, more preferably about 0 to 130 ° C.

In the heat-resistant film having a heat-resistant adhesive according to the present invention, the solution composition of the heat-resistant adhesive in which the above-mentioned resin component is dissolved in an organic polar solvent is prepared by mixing an aromatic polyimide film, a polyamide film and a polyether. Teru-
Apply to one or both sides of a heat-resistant film such as terketone or polyethersulfone, and apply the applied layer to 80 to 2
An uncured heat-resistant adhesive from which the solvent has been removed to 1% by weight or less (preferably the solvent remaining ratio is 0.5% by weight or less) by drying at a temperature of 00C for 20 seconds to 100 minutes. (A dry film or a sheet having a thickness of about 1 to 200 μm) or a method of transferring this thin film to another heat-resistant film.

The tape with a heat-resistant adhesive of the present invention is obtained as a tape by slitting the heat-resistant film having the heat-resistant resin adhesive obtained as described above.

The tape with a heat-resistant adhesive of the present invention can be used, for example, to cover and insulate an electric conductor. Examples of the conductor include metals and alloys such as iron, aluminum, copper, and brass, and superconducting materials such as niobium-titanium. The shape of the conductor is not particularly limited, but a foil or a wire is suitably used, and the wire may be a round bar or a polygonal bar.

The tape with a heat-resistant adhesive according to the present invention is, for example, one or a plurality of wires bundled, and the bundle is wound once or more times with the tape, and a part of the tape is covered. -After winding while wrapping, heat to cure the adhesive layer before use. Although there is no need to pressurize during heating, the pressure can increase the adhesion. Also,
The tape with a heat-resistant adhesive of the present invention can be suitably used for laminating with a copper foil.

[0039]

The present invention will be described below in further detail with reference to examples. In the following examples, logarithmic viscosities (ηi
nh) is a solution prepared by uniformly dissolving polyimide siloxane in N-methyl-2-pyrrolidone so that the concentration becomes 0.5 g / 100 ml of a solvent, and the solution is prepared using a Cannon-Fenske viscometer. And the viscosity of the solvent were measured at 30 ° C. and the values were calculated by the following formula. Logarithmic viscosity (ηinh) = [ln (solution viscosity / solvent viscosity)] / concentration of solution

The softening temperature of the polyimide siloxane film is a value obtained by measuring the tan δ (high temperature side) of a viscoelastic peak in a viscoelasticity test using a mechanical spectrometer RDS-2 manufactured by Rheometrics.

The modulus of elasticity of the polyimide siloxane is a result of a measurement using a tensile tester manufactured by Intesco Corporation at a tensile speed of 5 mm / min.

The adhesive strength was measured using a tensile tester manufactured by Intesco Co. at a peeling speed of 50 mm / min, a measuring temperature of 25 ° C. at 90 °, and a measuring temperature of 180 ° C. at 180 °.
A peel test was performed, and a 180 ° shear test was performed at a measurement temperature of −195 ° C. for measurement.

[Production of Imidosiloxane Oligomer] Reference Example 1 2,3,3 ′, 4 ′ was placed in a 500 ml glass flask equipped with a thermometer, a charging / discharging port, and a stirrer.
-Biphenyltetracarboxylic dianhydride (a-BPD
A) 0.054 mol, ω, ω′-bis (3-aminopropyl) polydimethylsiloxane (manufactured by Shin-Etsu Silicon Co., Ltd., X-22-161AS, n: 9) 0.027 mol,
And N-methyl-2-pyrrolidone (NMP) 160
g, and heated to a temperature of 50 ° C. in a nitrogen stream and stirred at this temperature for 2 hours to form an amic acid oligomer.
Next, the temperature of the reaction solution was raised to about 200 ° C., and the mixture was stirred at that temperature for 3 hours to produce an imide siloxane oligomer having an anhydride group at a terminal (A-1 component, average polymerization degree: 1).

Reference Examples 2 to 3 The same procedures as in Reference Example 1 were carried out except that a-BPDA, diaminopolysiloxane (the above-mentioned X-22-161AS) and NMP were used in the amounts shown in Table 1, respectively. (A-2, average degree of polymerization: 2, A-3, average degree of polymerization: 6) having the following formulas:

[Production of aromatic diamine imide oligomer] Reference Example 4 The amount of a-BPDA, 2,2-bis [4-
(4-aminophenoxy) phenyl] propane (BAP
P) and NMP were charged as in Reference Example 1, respectively.
Stir at 50 ° C. for 2 hours in a nitrogen stream to produce an amic acid oligomer, then raise the temperature of the reaction solution to about 200 ° C., and stir at that temperature for 3 hours to obtain an aromatic diamine having an amino group at a terminal. A imide oligomer (B-1 component, average degree of polymerization: 1) was produced.

REFERENCE EXAMPLES 5-6 a-BPDA, BAPP and NMP in the amounts shown in Table 1
In the same manner as in Reference Example 4, except that an aromatic diamine-based oligomer having a terminal amino group was used.
2 (average degree of polymerization: 2) and B-3 (average degree of polymerization: 1)
0) were each produced.

[0047]

[Table 1]

[Method for Producing Polyimide Siloxane] Reference Example 7 The imide siloxane oligomer (A-
3 components) 0.0025 mol of a 20% by weight NMP solution, and 0.0025 mol of the aromatic diamine-based imide oligomer (component B-3) produced in Reference Example 7 of 20% by weight of N
The MP solution was charged into a 500-ml glass flask, heated in a nitrogen stream and stirred at 50 ° C. for 1 hour in the same manner as in Reference Example 1 to generate a polyamic acid block polymer, and then heated. And stirred at 200 ° C. for 3 hours to produce a polyimidesiloxane (block polymer). This polyimide siloxane had an imidization ratio of 95% or more and an intrinsic viscosity of 0.45. Logarithmic viscosity of each manufactured polyimide siloxane, and
Table 2 shows the modulus of elasticity and the softening temperature of this polyimide siloxane film.

Reference Examples 8 to 9 The same procedure as in Reference Example 7 was repeated except that the oligomers prepared in Reference Examples 1 to 6 were used in the amounts and reaction conditions shown in Table 2 to obtain polyimide siloxane ( Block polymers) were each produced. Table 2 shows the logarithmic viscosities of the produced polyimide siloxanes, and the elastic modulus and the softening temperature of the film made of the polyimide siloxanes.

[0050]

[Table 2]

Example 1 [Preparation of solution composition of heat-resistant adhesive] The polyimide siloxane (block polymer, A-3) prepared in Reference Example 7 was placed in a 500-mL glass flask.
-B-3) 50 g, epoxy resin (manufactured by Yuka Shell Epoxy Co., Ltd., trade name: Epicoat 807) 30 g, phenol novolak type curing agent (manufactured by Meiwa Kasei Co., Ltd., H-
1) 20 g and the curing accelerator 2-phenylimidazole 0.1 g
005 g and 185 g of dioxane were charged and stirred at room temperature (25 ° C.) for about 2 hours to prepare a uniform heat-resistant resin adhesive solution composition (viscosity at 25 ° C .: 7 poise). This solution composition maintained a uniform solution state (viscosity) even when left at room temperature for one week.

[Production of heat-resistant film having heat-resistant adhesive] A solution composition of the above-mentioned heat-resistant resin adhesive was applied to a polyimide film [product name: UPILE manufactured by Ube Industries, Ltd.]
125 μm on XS type (3,3 ′, 4,4′-biphenyltetracarboxylic dianhydride-paraphenylenediamine aromatic polyimide film), thickness 75 μm]
m at a thickness of 50 m.
After heating at 100 ° C. for 30 minutes and drying at 100 ° C., a heat-resistant adhesive layer (uncured dried layer, softening point: 60 ° C.) having a thickness of about 25 μm was formed on the polyimide film.

[Peel strength to metal] The polyimide film having the heat-resistant adhesive layer and the treated surface of copper foil (35 μm) are overlapped and passed through a laminate roll heated to 130 ° C. while applying pressure. By pressing the laminate at 100 ° C. for 1 hour at 120 ° C.
For 1 hour and then at 160 ° C. for 10 hours to cure the heat-resistant resin adhesive layer to produce a laminate. The adhesive strength of the obtained laminate was measured, and the results are shown in Table 3.

[Production of Tape with Heat-Resistant Adhesive and Measurement of Strength of Bonded Surface] The polyimide film having the heat-resistant adhesive was slit to a width of 10 mm to obtain a tape with a heat-resistant adhesive. Was. The surfaces of the Tooh adhesive coated with each other are overlapped with each other with a length of 5 mm (area of the overlapped portion: 0.5 cm ² ), and passed through a laminating roll heated to 130 ° C. while applying pressure. 1 hour at 100 ° C., 1 hour at 120 ° C., and 16
Heat treatment was performed at 0 ° C. for 10 hours. The tensile shear strength of this sample was measured. Table 3 shows the results.

[Production of an electric conductor covered and insulated with a polyimide film having a heat-resistant adhesive] A flat wire [2 mm × 10 m] in which superconducting wires of niobium-titanium are bundled
m), the above-mentioned tape slit to a width of 10 mm was wound around with a 1/2 overwrap, with the surface having the adhesive layer out of the way. Ten rectangular wires wound in this manner were superposed, cured at a pressure of 10 kg / mm, at a temperature of 160 ° C. for 1 hour, and an electric conductor block covered with a polyimide film having a heat-resistant adhesive layer and insulated was manufactured. This block was placed in liquid nitrogen from room temperature, held for 30 minutes, and then returned to room temperature. The cycle was repeated twice to test low temperature resistance. No defects such as cracks were observed in the blocks after the test. Examples 2 to 4 In the same manner as in Example 1, except that the polyimide siloxanes produced in Reference Examples 8 and 9 were used as shown in Table 3 and the composition of each component was as shown in Table 3. And a heat-resistant adhesive solution composition were prepared, respectively, to produce a polyimide film having the heat-resistant adhesive. Thereafter, in the same manner as in Example 1, the peel strength from the copper foil and the tensile shear strength when the polyimide films were bonded to each other were measured. Table 3 shows the results. An electric conductor block was manufactured in the same manner as in Example 1, and a low-temperature resistance test was performed in the same manner. No defect was found in the block.

Comparative Example 1 50 g of a phenol novolak type epoxy resin (Epicoat 152, manufactured by Yuka Shell Co., Ltd.), 30 g of phenol novolak (H-1, manufactured by Meiwa Kasei Co., Ltd.), 0.1% of imidazole curing catalyst. A solution composition of a heat-resistant adhesive was prepared in the same manner as in Example 1 except that 01 g and 200 g of dioxane were used. Example 1 except that this solution composition was used
A tape was formed in the same manner as described above, and a block was further formed. When the block was subjected to a cyclic test of liquid nitrogen twice at room temperature, cracks occurred in the adhesive layer of the block.

[0057]

[Table 3]

[0058]

According to the present invention, the tape with heat-resistant adhesive is used.
The heat-resistant film can be bonded at a relatively low temperature while the copper foil and the heat-resistant film are bonded together, and the laminate bonded with the heat-resistant adhesive has an adhesive layer showing a sufficient adhesive strength,
In addition, since it exhibits excellent heat resistance, it does not swell or peel off the adhesive layer even in a high-temperature environment, and has appropriate strength as well as adhesive strength.

 ──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor Toshiaki Soda 3-10 Nakamiyakitamachi, Hirakata City, Osaka Ube Industries, Ltd.

Claims (4)

[Claims] 1. A heat-resistant adhesive thin film comprising a polyimide as a main component and having a modulus of elasticity of 250 kg / mm ² or less on one or both sides of the heat-resistant film. The adhesive strength at 180 ° C. (180 ° peel test) measured for a laminate formed by bonding a polyimide film and a heat-resistant adhesive was 0.9 k.
A tape with a heat-resistant adhesive obtained by slitting a heat-resistant film having a heat-resistant adhesive layer having a heat resistance of at least g / mm ² . 2. The tape with heat-resistant adhesive according to claim 1, wherein the heat-resistant adhesive is obtained by adding a fine inorganic filler in a ratio of 0.2 to 5 parts by weight with respect to 100 parts by weight of the polyimide. H. 3. The tape with a heat-resistant adhesive according to claim 1, wherein a metal foil such as a copper foil is laminated on another surface of the heat-resistant adhesive layer. 4. A heat-resistant adhesive comprising: (a) an aromatic tetracarboxylic acid component mainly composed of biphenyltetracarboxylic acids as a polyimide, and the following general formula (1): (Wherein R in the formula represents a divalent hydrocarbon residue;
₁ , R ₂ , R ₃ and R ₄ represent a lower alkyl group or a phenyl group, and n represents an integer of 3 to 60. 100 parts by weight of a soluble polyimide siloxane obtained from 10 to 80 mol% of a diaminopolysiloxane and 20 to 90 mol% of an aromatic diamine represented by the following formula:
The tape with a heat-resistant adhesive according to claim 1, which is a heat-resistant adhesive comprising (b) 15 to 80 parts by weight of an epoxy compound having an epoxy group, and (c) an epoxy curing agent as a resin component.