JP3270378B2 - Metal / resin composite, method for producing the same, and substrate for flexible circuit wiring board - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a metal / resin composite having excellent heat resistance and excellent workability at a low temperature, a method for producing the same, and a substrate for a flexible circuit wiring board.

[0002]

2. Description of the Related Art A metal / resin composite in which a conductor layer is formed on a flexible film-like substrate is formed by forming a wiring with the conductor layer, and as a substrate for a flexible printed wiring board, an electric wire requiring flexibility and space saving. -Widely used for wiring of electronic devices. In recent years, in particular, mobile phones, notebook computers, video cameras, and the like have been reduced in size and size, and their use has been increasingly spurred. On the other hand, demands for high reliability, fine pitch and high heat resistance for flexible printed wiring boards are also increasing. A conventional flexible printed wiring board substrate has a structure (three-layer flexible) in which a base material such as a polyimide film and a wiring layer such as a copper foil are sandwiched by an adhesive such as an epoxy resin.
However, in order to satisfy these requirements of high reliability, etc., among the constituent materials, the polyimide film has high heat resistance, flame retardancy and excellent electrical insulation, whereas the adhesive layer has relatively low heat resistance. Physical properties were the bottleneck. Therefore, a so-called two-layer flexible in which the wiring layer is in direct contact with the polyimide as the base material without using such an adhesive has been developed. The method for producing this two-layer flexible film is to apply a polyimide (or a precursor thereof) solution on a metal foil, and then heat and dry it.
There are a casting method for curing and a vapor deposition method for forming a conductor layer by vapor-depositing a metal on a polyimide film. However, during each manufacturing process, high-performance and large-scale manufacturing equipment is required in each process of vapor deposition in the casting method, drying at a high temperature after coating in the casting method, and the manufacturing cost is larger than that of the conventional method. Has the disadvantage that On the other hand, the use of a thermoplastic polyimide resin as an adhesive is also considered for the above-mentioned three-layer flexible film, but the bonding processing temperature is inevitably increased, and the manufacturing apparatus becomes large in scale. If the glass transition temperature of the polyimide resin is lowered in order to impart low temperature processability to the adhesive, there is a problem that the heat resistance characteristic of the polyimide resin cannot be fully utilized.

[0003]

Accordingly, as a result of intensive studies on a metal / resin composite having excellent heat resistance and excellent workability at low temperatures, the high reliability of the polyimide as shown in the present invention was found. We have developed a metal-resin composite that is sufficiently shown and can be manufactured under mild conditions such as the conventional three-layer flexure.

[0004]

Means for Solving the Problems The present invention is, 1) (A) main
3,3 ', 4,4'-biphenyltetraca
Rubonic anhydride and 3,3 ', 4,4'-benzopheno
Tetracarboxylic dianhydride, the main amine component
Is 2,2-bis (4- (4-aminophenoxy) fe
Nyl) propane, 1,3-bis (3-aminophenoxy)
B) Selected from the group of benzene and dimethylphenylenediamine
One or more diamines and general formula
100 parts by weight of a polyimide resin having a glass transition temperature of 350 ° C. or less and soluble in an organic solvent comprising the diaminosiloxane compound represented by (1), and (B) at least two or more resins per molecule. Epoxy compounds 5 to 10 having an epoxy group
0 parts by weight and (C) 0.1-30 parts by weight of a compound having an active hydrogen group capable of reacting with the epoxy compound through a resin adhesive layer containing as main components a metal foil and heat resistance. A metal / resin composite having a layer structure in which a resin layer is present. 2) (A) The main acid component is
3,3 ', 4,4'-biphenyltetracarboxylic acid
Water and 3,3 ', 4,4'-benzophenonetetracal
A boric acid dianhydride wherein the main amine component is 2,2-
Bis (4- (4-aminophenoxy) phenyl) propa
And 1,3-bis (3-aminophenoxy) benzene
One selected from the group of dimethylphenylenediamine
Or two or more diamines and a diamine represented by the general formula (1)
100 parts by weight of a polyimide resin having a glass transition temperature of 350 ° C. or less soluble in an organic solvent composed of an aminosiloxane compound, and (B) 5 to 100 parts by weight of an epoxy compound having at least two epoxy groups in one molecule. , (C)
A layer of a resin adhesive containing, as a main component, 0.1 to 30 parts by weight of a compound having an active hydrogen group capable of reacting with the epoxy compound is formed on both sides of the heat-resistant resin layer, A metal / resin composite having a layer structure in which a metal foil exists through a layer. 3) The metal / resin composite according to (1) or (2), wherein the component (A) is a polyimide resin containing the siloxane compound represented by the general formula (1) in an amount of 5 to 70 mol% of the total amount of the amine components. .

[0005]

Embedded image (Wherein, R ₁ and R _{2 are} divalent aliphatic or aromatic groups having 1 to 4 carbon atoms R ₃ , R ₄ , R ₅ and R _{6 are} monovalent aliphatic or aromatic groups k : 1 or 2)

[0006] 4) Component (A) comprises amol of 3,3 ′, 4,4′-biphenyltetracarboxylic dianhydride and 3,3 ′,
4,4'-benzophenonetetracarboxylic dianhydride b
And mol as an acid component, selected from the group consisting of c mol of 2,2-bis (4- (4-aminophenoxy) phenyl) propane and 1,3-bis (3-aminophenoxy) benzene and dimethylphenylenediamine. One or two kinds of diamines (d mol) and the siloxane compound e mol represented by the general formula (1) are used as amine components, and the molar ratio of a, b, c, d, and e is 0.5 ≦ a / ( a + b) ≦ 0.8, 0.9
≦ (a + b) / (c + d + e) ≦ 1.1, and 0.
The metal / resin composite according to ( 3 ), which is a polyimide resin in which both components are reacted at a ratio of 05 ≦ e / (c + d + e) ≦ 0.5 to form an imide ring closure. 5) The metal / resin composite according to any one of (1) to ( 4 ), wherein the heat-resistant resin layer is a polyimide film. 6) The metal foil is a copper foil (1)-
The metal-resin composite according to any one of (5) . 7) (A) The main acid component is 3,3 ′, 4,4′-biphe
Nyltetracarboxylic dianhydride and 3,3 ', 4,4'-
Benzophenone tetracarboxylic dianhydride, mainly
Amine component is 2,2-bis (4- (4-aminophen)
Noxy) phenyl) propane, 1,3-bis (3-amido)
Nophenoxy) benzene and dimethylphenylenediamine
One or more diamines selected from the group of
From the diaminosiloxane compound represented by the general formula (1)
Comprising a soluble glass transition temperature in an organic solvent is 100 parts by weight 350 ° C. or less of the polyimide resin, an epoxy compound having a (B) at least two or more epoxy groups in one molecule 5
A resin adhesive solution containing, as main components, 100 to 100 parts by weight and (C) 0.1 to 30 parts by weight of a compound having an active hydrogen group capable of reacting with the epoxy compound. A method for producing a metal-resin composite, which comprises a step of applying the composition on a substrate, heating and drying, thermocompression bonding with a heat-resistant resin film or metal foil, and post-curing at a temperature higher than the thermocompression bonding. 8) (A) The main acid component is 3,3 ′, 4,4′-biffee
Nyltetracarboxylic dianhydride and 3,3 ', 4,4'-
Benzophenone tetracarboxylic dianhydride, mainly
Amine component is 2,2-bis (4- (4-aminophen)
Noxy) phenyl) propane, 1,3-bis (3-amido)
Nophenoxy) benzene and dimethylphenylenediamine
One or more diamines selected from the group of
From the diaminosiloxane compound represented by the general formula (1)
Comprising a soluble glass transition temperature in an organic solvent is 100 parts by weight 350 ° C. or less of the polyimide resin, an epoxy compound having a (B) at least two or more epoxy groups in one molecule 5
A resin adhesive solution containing, as main components, 100 to 100 parts by weight and (C) 0.1 to 30 parts by weight of a compound having an active hydrogen group capable of reacting with the epoxy compound is applied on a heat-resistant resin film. After heating and drying, and thermocompression bonding with the metal foil, apply the resin adhesive solution to the other surface of this heat-resistant resin film in the same manner, heat and dry, thermocompression-bond the metal foil, and at a temperature equal to or higher than thermocompression bonding A method for producing a metal / resin composite, comprising a step of post-curing. 9) (A) The main acid component is 3,3 ′, 4,4′-biffee
Nyltetracarboxylic dianhydride and 3,3 ', 4,4'-
Benzophenone tetracarboxylic dianhydride, mainly
Amine component is 2,2-bis (4- (4-aminophen)
Noxy) phenyl) propane, 1,3-bis (3-amido)
Nophenoxy) benzene and dimethylphenylenediamine
One or more diamines selected from the group of
From the diaminosiloxane compound represented by the general formula (1)
Comprising a soluble glass transition temperature in an organic solvent is 100 parts by weight 350 ° C. or less of the polyimide resin, an epoxy compound having a (B) at least two or more epoxy groups in one molecule 5
A resin adhesive solution containing, as main components, 100 to 100 parts by weight and (C) 0.1 to 30 parts by weight of a compound having an active hydrogen group capable of reacting with the epoxy compound, is applied on a metal foil and heated.・ After drying, the method comprises a step of thermocompression bonding with a heat-resistant resin film sandwiched between the two metal foils such that the resin adhesive solution surface is on the inside, and post-curing at a temperature equal to or higher than the thermocompression bonding. Manufacturing method of metal / resin composite. 10) The method for producing a metal-resin composite according to any one of (7) to (9) , wherein the thermocompression bonding temperature is 180 ° C or lower. 11) The thermocompression bonding is continuously performed using a heated roll press or a belt press (7) to (1 ).
0) The method for producing a metal-resin composite according to any one of the above. 12) A substrate for a flexible printed wiring board using the metal / resin composite according to any one of (1) to (6) .

[0007]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The resin adhesive used in the present invention has a glass transition temperature of at least two per molecule per 100 parts by weight of a polyimide resin soluble in an organic solvent having a glass transition temperature of 350 ° C. or lower. Epoxy compound 5 having an epoxy group
-100 parts by weight, and 0.1-30 parts by weight of a compound having an active hydrogen group capable of reacting with the epoxy compound.

[0008] The polyimide resin soluble in an organic solvent constituting the resin adhesive of the present invention comprises 3,3 ', 4,4'-biphenyltetracarboxylic dianhydride, 3,3', It is preferable to use 4,4′-benzophenonetetracarboxylic dianhydride in consideration of its solubility after imidization, adhesiveness, and heat resistance. Furthermore, the abundance ratio of these was a mole of 3,3 ′, 4,4′-biphenyltetracarboxylic dianhydride and b mole of 3,3 ′, 4,4′-benzophenonetetracarboxylic dianhydride. In this case, it is more preferable that 0.5 ≦ a / (a + b) ≦ 0.8.

The aromatic diamine used in the production of the polyimide includes, for example, 2,2-bis (4-
(4-aminophenoxy) phenyl) propane, 1,3
-Bis (3-aminophenoxy) benzene, 2,5-diamino-para-xylene and the like are preferably used alone or in combination. It is more preferable to use a siloxane compound represented by the formula (1) as one component of the diamine component of the polyimide in an amount of 5 to 50 mol% of the total amount of the diamine component. If the total amount of the diamine components is less than 5 mol%, the processability at low temperatures and the solubility in organic solvents are reduced, and if it exceeds 50 mol%, the glass transition temperature is remarkably lowered, and there is a problem in heat resistance. Further, the value of k in the general formula (1) is preferably 1 or 2. k is 0
When k is 3 or more, the effect of addition is difficult to be seen, and when k is 3 or more, it is difficult to exhibit adhesive strength to a heat-resistant resin film at low temperatures. In particular, k is preferably 1 from the viewpoints of adhesiveness and heat resistance.

This polyimide resin must have thermoplasticity in order to thermocompression-bond a metal foil and a heat-resistant resin film. Its glass transition temperature must be 350 ° C. or less. More desirably, the temperature is 180 ° C. or lower. At this temperature, thermocompression bonding between the metal foil and the heat-resistant resin film can be performed at 180 ° C. or lower, and various conditions during processing become advantageous.

[0011] The equivalent ratio of the acid component to the amine component in the polycondensation reaction is an important factor that determines the molecular weight of the obtained polyimide resin. It is well known that there is a correlation between the molecular weight and physical properties of a polymer, especially the number average molecular weight and mechanical properties. The higher the number average molecular weight, the better the mechanical properties. Therefore, in order to obtain practically excellent strength, it is necessary to have a high molecular weight to some extent. In the present invention,
The equivalent ratio r between the acid component and the amine component is more preferably 0.900 ≦ r ≦ 1.10, more preferably 0.975 ≦ r ≦ 1.025. Here, r = [equivalent number of all acid components] / [equivalent number of all amine components]. When r is less than 0.900, the molecular weight is low and the polymer becomes brittle, so that the adhesive strength is weak. On the other hand, if it exceeds 1.10, unreacted carboxylic acid may be decarbonated during heating to cause gas generation and foaming, which is not preferable.

The addition of dicarboxylic anhydride or monoamine for controlling the molecular weight of the polyimide resin does not hinder the addition of the dicarboxylic acid anhydride or monoamine as long as the acid / amine molar ratio is within the above-mentioned range. The polyimide resin can be obtained by dehydrating and ring-closing a polyamic acid as a precursor obtained by reacting a tetracarboxylic dianhydride with a diamine. The reaction between the tetracarboxylic dianhydride and the diamine is carried out by a known method in an aprotic polar solvent. The aprotic polar solvent is N, N-dimethylformamide (DM
F), N, N-dimethylacetamide (DMAC), N
-Methyl-2-pyrrolidone (NMP), tetrahydrofuran (THF), diglyme, cyclohexanone, 1,
4-dioxane (1,4-DO) and the like. As the aprotic polar solvent, only one kind may be used, or two or more kinds may be used as a mixture. At this time, a non-polar solvent compatible with the aprotic polar solvent may be mixed and used. Aromatic hydrocarbons such as toluene, xylene, and solvent naphtha are often used. The proportion of the non-polar solvent in the mixed solvent is preferably 50% by weight or less. This is because if the amount of the nonpolar solvent is 50% by weight or more, the dissolving power of the solvent may be reduced and polyamic acid may be precipitated. The reaction between the tetracarboxylic dianhydride and the diamine is
The well-dried diamine component is dissolved in the above-mentioned dehydrated and purified reaction solvent, and the ring closure ratio is 98%, more preferably 99%.
The above-mentioned well-dried tetracarboxylic dianhydride is added to proceed the reaction.

Although the polyamic acid thus obtained has better solution solubility than the polyimide of the corresponding structure, when it is mixed with the epoxy resin of the component (B) or the active hydrogen compound of the component (C) in the present invention. In addition, polyamic acid reacts with these components, and it is difficult to exhibit the original performance of polyimide. So, before mixing with these ingredients,
It is desirable that this polyamic acid solution be subjected to heat dehydration cyclization in an organic solvent to imidize it into a polyimide. Water generated by the imidization reaction interferes with the ring closure reaction,
An organic solvent that is incompatible with water is added to the system, azeotroped, and discharged out of the system using a device such as a Dean-Stark tube. As the organic solvent incompatible with water, aromatic hydrocarbons such as benzene, toluene, and xylene are used. Further, the use of a compound such as acetic anhydride, β-picoline, pyridine or the like as a catalyst for the imidization reaction is not hindered.

In the present invention, the higher the degree of imide ring closure, the better the degree of imidization, and it is desirable that the imidization ratio is 95% or more, more preferably 98% or more. Component (B) used in the resin adhesive of the present invention
The epoxy compound is not particularly limited as long as it has two epoxy groups in one molecule and has compatibility with the polyimide resin of the component (A). Those having good properties are preferred. For example, bisphenol A type diglycidyl ether, biphenyl type diglycidyl ether, tetramethylbiphenyl type diglycidyl ether, diphenyl ether type epoxy compound and the like can be mentioned.

The amount ratio of the epoxy compound is 5 to 100 parts by weight based on 100 parts by weight of the component (A) polyimide resin.
In particular, it is preferably in the range of 10 to 70 parts by weight. 5
If the amount is less than 100 parts by weight, the effect of adding an uncured epoxy compound to lower the softening temperature of the resin composition and increase the low-temperature processability is unlikely to be exerted. If the amount exceeds 100 parts by weight, the heat resistance of the polyimide resin is impaired.

The compound (C) having an active hydrogen group capable of reacting with the epoxy compound used in the resin adhesive of the present invention is compatible with the polyimide resin of the component (A) and the epoxy compound of the component (B). Those having good solubility and solubility of the polyimide resin in the solvent are preferable. For example, resol, novolak, amine compound and the like can be mentioned, but use of novolak resin is particularly desirable from the viewpoint of storage stability of the resin adhesive before processing, mechanical properties of the resin after processing and heat resistance. The compounding ratio of component (C) is polyimide resin 10 of component (A).
It is 0.1 to 30 parts by weight, more preferably 0.5 to 20 parts by weight, based on 0 parts by weight. If the amount is less than 0.1 part by weight, the reaction rate of the uncured epoxy compound becomes extremely low, and the effect desired in the present invention does not appear. Further, it is difficult to control the flow of the resin when the elastic modulus of the resin at a high temperature is low. If the amount is more than 30 parts by weight, the flexibility and heat resistance of the resin composition are impaired, and a gel is easily generated in a resin solution state, which is not preferable. The resin adhesive in the present invention may contain a fine inorganic or insoluble / infusible organic filler as long as its workability and heat resistance are not impaired.

In the present invention, an epoxy compound or a compound having an active hydrogen group capable of reacting with the epoxy compound is directly added to the obtained polyimide solution to obtain a resin adhesive solution. Further, the polyimide solution is poured into a poor solvent, and the solid polyimide resin obtained by reprecipitation is again dissolved in an organic solvent to obtain a filtration and purification varnish, and an epoxy compound or active hydrogen capable of reacting with the epoxy compound. It is also possible to add compounds having groups. The resin adhesive obtained by adding an epoxy compound and a compound having an active hydrogen group capable of reacting with the epoxy compound to the polyimide resin used in the present invention has an apparent glass transition temperature lower than the glass transition temperature of the polyimide resin. Workability is improved, and bonding between the metal foil and the heat-resistant resin layer at a low temperature and in a short time becomes possible. On the other hand, the bonding strength at each interface after the bonding process is higher than that of the polyimide resin, and physical properties in a high temperature region such as no occurrence of voids due to peeling or outgassing even after high heat or thermal shock such as a soldering process. Is improved. Although the detailed mechanism for this peculiar phenomenon is still unclear, the low molecular weight product of the reaction between the epoxy compound and the compound having an active hydrogen group acts as a plasticizer on the polyimide resin of a specific structure. It lowers the modulus of elasticity at a temperature lower than the glass transition temperature of the polyimide resin, thereby improving workability at a low temperature such as adhesiveness and workability.
On the other hand, after the thermocompression bonding step, it is considered that a three-dimensional network structure is formed by the heat applied during the compression bonding, which lowers the fluidity of the polyimide resin, thereby maintaining or improving the heat resistance of the polyimide resin. With the above mechanism, both low-temperature workability and high-temperature heat-reliability can be achieved.

Examples of the heat-resistant resin film used in the present invention include polyamide films such as polyimide films and aramid resins, polyester films such as polyethylene terephthalate and liquid crystal polymers, and polyether sulfide films. However, the use of a polyimide film is preferred in order to develop the high reliability and heat resistance that are features of the present invention.

Examples of the metal foil used in the present invention include foil copper, aluminum, nickel, and constantan. In particular, when used as a substrate for a flexible circuit wiring board, it is preferable to use a copper foil from the viewpoint of adhesion to a resin adhesive and conduction resistance.

The metal / resin composite of the present invention is produced by bonding a metal foil and a heat-resistant resin film using the resin adhesive obtained as described above. The manufacturing process consists of forming a resin adhesive layer on a metal foil or heat-resistant resin film and then thermocompression-bonding the corresponding heat-resistant resin film or metal foil, and forming a sheet between the metal foil and heat-resistant resin film. A method in which thermocompression bonding is performed with an isosolid resin adhesive interposed therebetween can be used, but the former method is preferred from the viewpoint of the number of steps and the ease of steps. Hereinafter, the former manufacturing method will be described.

The formation of the resin adhesive layer on the metal foil or the heat-resistant resin film (substrate) is carried out by casting the resin adhesive solution obtained as described above on the substrate and drying it. It is common. In the case of a single-sheet product, spin coating or an applicator can be used for coating, but continuous coating using a bar coater or a die coater enables formation with higher productivity than a roll-shaped substrate. Drying is performed by a batch type hot air dryer or a hot plate in the case of a sheet-like product, or by an in-line drying device in the case of a roll. Although the drying temperature depends on the type of each component in the resin adhesive, the boiling point of the solvent, and the vapor pressure, the amount of residual solvent in the resin adhesive layer falls sufficiently below the glass transition temperature of the polyimide resin and below the thermocompression bonding temperature. (5% or less). The drying time also depends on the components of the resin adhesive, but it is generally within one hour to suppress the reaction of the epoxy resin before the thermocompression bonding during the resin bonding and exhibit the performance during / after the thermocompression bonding. desirable. The substrate on which the resin adhesive solution is applied can be either a metal foil or a heat-resistant resin film.

The thermocompression bonding of the corresponding heat-resistant resin film or metal foil (both sides) to the surface of the resin adhesive in the form of a substrate can be carried out by using a sheet press, a hot roll or a belt press. In particular, the use of the latter two makes it possible to produce with high productivity by combining a sheet-like base material with a counterpart. Further, by performing the thermocompression bonding at a temperature of 180 ° C. or less, a steam press which has been frequently used can be used for a single-wafer press, and a conventional three-layer flexible manufacturing apparatus can be used as it is for a hot roll. For example, it is possible to manufacture the metal-resin composite of the present invention without investing in new equipment for hot pressing. In addition, when using a hot roll, not only metal but also fluoro rubber etc. can be used for the roll material,
Advantages such as a product having a better appearance can be produced.

Further, especially when using a hot roll or belt press, or when performing thermocompression bonding in a short time even with a single-wafer press, the obtained composite is further post-cured at a temperature equal to or higher than thermocompression bonding. Can exhibit higher performance. When a hot roll or a belt press is used, the heating time at the time of pressure bonding becomes short, and thus the reaction rate of the crosslinking reaction of the epoxy resin in the resin adhesive becomes small. For this reason, the introduction of post-curing is very effective to sufficiently advance this crosslinking reaction. The post-curing can be performed by placing the composite in a batch type hot air dryer in the form of a sheet or a roll and heating.

The metal-resin composite of the present invention has a structure in which a heat-resistant resin film and a metal foil are adhered one by one by the above-described method, in addition to a structure in which the metal foil is present on one side of the heat-resistant film, It is also possible to obtain a single heat-resistant film in which metal foils are stuck on both sides in the same manner. As a crimping method in this case, a resin adhesive is applied and dried on a surface of the heat-resistant resin film on which the metal foil is not adhered on one side prepared in advance, and the metal foil is thermocompressed.
A resin adhesive is applied and dried on a metal foil, and then heat-pressed to the surface of the heat-resistant resin film with the metal foil attached on one side where the metal foil is not attached. Is applied and dried, and then a metal foil is thermocompression-bonded to both sides thereof, or a metal foil previously coated and dried with a resin adhesive is thermocompression-bonded to both sides of a heat-resistant film.

Since the metal / resin composite thus obtained can be manufactured under mild conditions, it can be manufactured with inexpensive equipment such as a conventional three-layer flexible manufacturing apparatus. Moreover, the obtained metal-resin composite does not generate gas due to deterioration or volatilization of decomposition products in a soldering step or the like, and does not cause blistering in the material, and has high heat resistance and reliability. Hereinafter, the present invention will be described in detail with reference to examples, but the present invention is not limited to these examples.

[0026]

Example 1 In a four-necked flask equipped with a dry nitrogen gas inlet tube, a cooler, a thermometer, and a stirrer, 1428 g of dehydrated and purified N-methyl-2-pyrrolidone (NMP) was placed, and nitrogen gas was flowed. While stirring the system, 82.1 g of 2,2-bis (4- (4-aminophenoxy) phenyl) propane (BAPP)
(0.10 mol), 38.7 g (0.20 mol) of 1,3-bis (3-aminophenoxy) benzene (APB),
Charge 24.9 g (0.10 mol) of α, ω-bis (3-aminopropyl) dimethyldisiloxane (APDS, formula (2)) and stir until uniform. After dissolving uniformly, 3,3 ′, 4,4′-biphenyltetracarboxylic dianhydride (BPDA) while maintaining the system at 20 ° C.
4g (0.28 mol), 3,3 ', 4,4'-benzophenonetetracarboxylic dianhydride (BTDA) 38.7
g (0.12 mol) was added in the form of a powder over 15 minutes, and then stirring was continued for 8 hours. During this time the flask is 20
C. After that, remove the nitrogen gas inlet tube and cooler,
A Dean-Stark tube filled with toluene was attached to the flask, and 612 g of toluene was added to the system. The system was heated to 175 ° C. instead of the oil bath, and the generated water was removed from the system. 6
After heating for an hour, no water was generated from the system. By cooling the system, the polyimide solution PI-
1 was obtained.

In a glass flask, a polyimide solution PI-
1, 500 g of bisphenol A type epoxy compound (Epicoat 828, Yuka Shell Epoxy Co., Ltd.) at room temperature
20g, xylenol resin (trade name: Xyloc,
10 g of Mitsui Toatsu Chemical Co., Ltd.) was gradually added while stirring the system, followed by stirring for 2 hours to prepare a resin adhesive solution I. The resin adhesive solution I was dried and coated with a bar coater to a thickness of 7 μm on an Iupirex 25SGA film (manufactured by Ube Industries, Ltd., 25 μm thickness), and then 100 ° C./5 minutes, 140 ° C./10 minutes In a hot air drier in this order to prepare a film II with an adhesive. This film with adhesive and electrolytic copper foil (Mitsui Metal Mining Co., Ltd.)
, 35 μm thick, one-sided roughened) were overlapped so that the roughened surface of the copper foil and the surface of the film coated with the resin adhesive were in contact with each other, and heated and pressed by a steam press at 180 ° C. and 30 kgf / mm ² for 30 minutes. . The appearance after the pressure bonding was good, with no bubbles present in the layer. A peel strength test was performed on the obtained flexible circuit board under the conditions of JIS-C6481. Peeling occurred at the interface between the resin adhesive layer and the Upilex layer, but the adhesive strength was 1.1 kg / cm, which was sufficiently large. When this flexible circuit board was placed on a solder bath heated to 260 ° C. for 60 seconds, no change was observed.

Example 2 The film II with adhesive used in Example 1 and the electrolytic copper foil were overlapped so that the roughened surface of the copper foil and the resin adhesive applied surface of the film were in contact with each other, and the metal heated to 180 ° C. The roll was pressed at a speed of 3.0 m / min while applying a linear pressure of 2 kg / cm between the roll and the fluororubber roll. After the pressure bonding, a heat treatment was sequentially performed in a hot air dryer in the order of 100 ° C./3 hours, 130 ° C./1 hour, and 180 ° C./2 hours to obtain a substrate for a flexible circuit. The appearance of the obtained composite was good, as in Example 1, with no air bubbles present in the layer. When a peel strength test was performed on the obtained flexible circuit board in the same manner as in the example, peeling occurred at the interface between the resin adhesive layer and the upirex layer,
The adhesive strength was very large at 1.8 kg / cm. In addition, this flexible circuit board is heated at 260 ° C.
No change was observed when the substrate was placed on a heated solder bath for 60 seconds.

Example 3 The resin adhesive solution I used in Example 1 was applied on a roughened surface of the electrolytic copper foil also used in Example 1 by a bar coater so as to have a thickness of 7 μm after drying. Then 100 ° C /
Drying was performed in a hot air drier in the order of 5 minutes and 140 ° C./10 minutes to prepare a copper foil III with an adhesive. The copper foil with adhesive III and the UPIREX 25SGA film are overlapped so that the film and the resin adhesive applied surface of the copper foil are in contact with each other.
The metal roll and the fluororubber roll heated to 80 ° C. were pressed at a speed of 3.0 m / min while applying a linear pressure of 2 kg / cm. After pressing, 10 minutes in a hot air dryer
Heat treatment was sequentially performed in the order of 0 ° C./3 hours, 130 ° C./1 hour, and 180 ° C./2 hours to obtain a flexible circuit board. The appearance of the obtained composite was good, as in Example 1, with no air bubbles present in the layer. When a peel strength test was performed on the obtained flexible circuit board in the same manner as in the example, peeling occurred at the interface between the resin adhesive layer and the upirex layer, but the adhesive strength was 2.0 k.
g / cm, which was very large. The flexible circuit board was placed on a solder bath heated to 260 ° C.
No change was seen after 0 seconds.

Example 4 The film with adhesive II used in Example 1 and the electrolytic copper foil were overlapped so that the roughened surface of the copper foil and the resin adhesive applied surface of the film were in contact with each other, and the metal heated to 180 ° C. The roll was pressed at a speed of 3.0 m / min while applying a linear pressure of 2 kg / cm between the roll and the fluororubber roll. On the film surface of the obtained composite, the resin adhesive solution I was dried and then applied with a bar coater so as to have a thickness of 7 μm, and then dried with hot air in the order of 100 ° C./5 minutes and 140 ° C./10 minutes. Drying was performed in the machine to produce An electrolytic copper foil is placed on the flexible circuit board with the adhesive so that the roughened surface of the copper foil and the resin adhesive applied surface of the composite are in contact with each other. / C
Pressure bonding was performed by passing the wire at a speed of 3.0 m / min while applying a linear pressure of m. After pressing, heat treatment is sequentially performed in a hot air drier in the order of 100 ° C./3 hours, 130 ° C./1 hour, 180 ° C./2 hours to obtain a flexible circuit board having copper foil layers formed on both sides of Upilex. Obtained. The appearance of the obtained composite was good without showing any bubbles in the layer. When the peel strength test was performed on the flexible circuit board in the same manner as in Example 1, peeling occurred at the interface between the resin adhesive layer and the upilex layer. The interface with the copper foil which was 1.8 kg / cm and the second pressure bonding was 1.6 kg / cm, which was also large. When this flexible circuit board was placed on a solder bath heated to 260 ° C. for 60 seconds, no change was observed.

COMPARATIVE EXAMPLE 1 In Example 1, a polyimide solution PI-1 was used instead of the resin adhesive solution I on a UPILEX 25 SGA film (Ube Industries, Ltd., 25 μm thick) so as to have a thickness of 7 μm after drying. With a bar coater and then 100
The film was dried in a hot air drier in the order of 5 ° C./5 minutes and 140 ° C./10 minutes to prepare a film with an adhesive, and a flexible circuit board was obtained by the same operation as described below. However, when the obtained flexible circuit board was placed on a solder bath heated to 260 ° C. for 60 seconds, enormous foaming occurred in the adhesive layer. When the peel strength test of the obtained flexible circuit board was performed, the adhesive strength at the interface between the resin adhesive layer and the upilex layer was as small as 0.3 kg / cm.

Comparative Example 2 In Example 1, instead of the resin adhesive solution I, a polyimide solution PI-1 was dried on a UPILEX 25SGA film (manufactured by Ube Industries, Ltd., having a thickness of 25 μm) so as to have a thickness of 7 μm. With a bar coater and then 100
C./5 minutes, 160.degree. C./5 minutes, 220.degree. C./5 minutes, dried in a hot air drier to form a film with adhesive,
Thereafter, a substrate for a flexible circuit was obtained by the same operation. When this flexible circuit board was placed on a solder bath heated to 260 ° C. for 60 seconds, no change was observed. However, in the obtained flexible circuit board,
When the peel strength test was performed in the same manner as in the above, the adhesive strength at the interface between the resin adhesive layer and the Upilex layer was 0.1 k.
g / cm.

Comparative Example 3 500 g of polyimide solution PI-1 in a glass flask
Then, at room temperature, bisphenol A type epoxy compound (Epicoat 828, manufactured by Yuka Shell Epoxy Co., Ltd.) 120
g and a xylenol resin (trade name: Xyloc) 60 g were gradually added while stirring the system, followed by stirring for 2 hours to prepare a resin adhesive solution IV. Upilex 25SGA
After drying the resin adhesive solution IV on a film (manufactured by Ube Industries, Ltd., 25 μm thick) with a bar coater to a thickness of 7 μm after drying, 100 ° C./5 minutes, 140 ° C./10
The film was dried in a hot air drier in the order of minutes to produce a film with an adhesive, but the resin adhesive layer on the film was uneven and brittle. Hereinafter, a flexible circuit board was obtained by the same operation. However, when the peel strength test was performed on the obtained flexible circuit board in the same manner as in Example 1, the material was broken in the resin adhesive layer, and the adhesive strength was as small as 0.2 kg / cm. .

[0034]

According to the present invention, it is possible to provide a highly reliable metal / resin composite having both heat resistance and workability at a low temperature. Since this metal / resin composite can be manufactured under mild conditions, it can be manufactured using existing inexpensive equipment such as a conventional three-layer flexible manufacturing apparatus, and the processing cost is added together with the necessary utility costs. Can be suppressed to a place close to the conventional three-layer flex. Moreover, the obtained metal
The resin composite has high heat resistance and high reliability without generating gas due to deterioration or volatilization of decomposition products in a soldering process or the like and causing blisters in the material. For this reason, it is extremely useful industrially as a material for electric and electronic devices requiring high reliability and heat resistance. As a method of using the resin composition of the present invention, the resin composition can be applied to a substrate for a flexible circuit wiring board for electric / electronic equipment requiring reliability, but is particularly required to have high heat resistance and reliability. Examples of the material include a substrate for a flexible circuit wiring board for a flexible / multi-layer flexible board.

──────────────────────────────────────────────────続 き Continuation of the front page (51) Int.Cl. ⁷ Identification symbol FI H05K 1/03 670 H05K 1/03 670Z (56) References JP-A-6-345964 (JP, A) JP-A-6-200216 (JP, A) JP-A-9-132710 (JP, A) JP-A-2-29328 (JP, A) JP-A-1-2444841 (JP, A) JP-A-6-128462 (JP, A) Kaihei 4-234191 (JP, A) (58) Field surveyed (Int. Cl. ⁷ , DB name) B32B 15/08 C09J 179/00-179/08

Claims (12)

(57) [Claims] (1) The main acid component is 3,3 ′, 4,
4'-biphenyltetracarboxylic dianhydride and 3,
3 ', 4,4'-benzophenonetetracarboxylic acid
Water, and the main amine component is 2,2-bis (4-
(4-aminophenoxy) phenyl) propane, 1,3
-Bis (3-aminophenoxy) benzene and dimethylphenyl
One or two selected from the group of enylene diamines
The above diamine and diaminosilo represented by the general formula (1)
100 parts by weight of a polyimide resin having a glass transition temperature soluble in an organic solvent comprising a xanse compound of 350 ° C. or lower,
(B) 5 to 100 parts by weight of an epoxy compound having at least two epoxy groups in one molecule, and (C) a compound having an active hydrogen group capable of reacting with the epoxy compound.
A metal-resin composite having a layer structure in which a metal foil and a heat-resistant resin layer are present via a resin adhesive layer containing 1 to 30 parts by weight as a main component. Embedded image (Wherein, R ₁ and R _{2 are} divalent aliphatic groups having 1 to 4 carbon atoms)
Or an aromatic group R ₃ , R ₄ , R ₅ , R ₆ : a monovalent aliphatic group or
Is an aromatic group k: 1 or 2) 2. The method according to claim 1, wherein (A) the main acid component is 3, 3 ′, 4,
4'-biphenyltetracarboxylic dianhydride and 3,
3 ', 4,4'-benzophenonetetracarboxylic acid
Water, and the main amine component is 2,2-bis (4-
(4-aminophenoxy) phenyl) propane, 1,3
-Bis (3-aminophenoxy) benzene and dimethylphenyl
One or two selected from the group of enylene diamines
The above diamine and diaminosilo represented by the general formula (1)
100 parts by weight of a polyimide resin having a glass transition temperature soluble in an organic solvent comprising a xanse compound of 350 ° C. or lower,
(B) 5 to 100 parts by weight of an epoxy compound having at least two epoxy groups in one molecule, and (C) a compound having an active hydrogen group capable of reacting with the epoxy compound.
A layer of a resin adhesive containing 1 to 30 parts by weight as a main component is formed on both sides of a heat-resistant resin layer, and has a layer structure in which a metal foil exists through the layer of the resin adhesive. A metal / resin composite. 3. The metal / resin composite according to claim 1, wherein the component (A) is a polyimide resin containing the siloxane compound represented by the general formula (1) in an amount of 5 to 70 mol% of the total amount of the amine components. body. 4. Component (A) comprising a mole of 3,3 ′, 4,4′-biphenyltetracarboxylic dianhydride and 3,3 ′,
4,4'-benzophenonetetracarboxylic dianhydride b
And mol as an acid component, selected from the group consisting of c mol of 2,2-bis (4- (4-aminophenoxy) phenyl) propane and 1,3-bis (3-aminophenoxy) benzene and dimethylphenylenediamine. One or two kinds of diamines (d mol) and the siloxane compound e mol represented by the general formula (1) are used as amine components, and the molar ratio of a, b, c, d, and e is 0.5 ≦ a / ( a + b) ≦ 0.8, 0.9
≦ (a + b) / (c + d + e) ≦ 1.1, and 0.
The metal / resin composite according to claim 3 , wherein the polyimide resin is a polyimide resin obtained by reacting both components at a ratio of 05 ≤ e / (c + d + e) ≤ 0.5 to close the imide. 5. The metal-resin composite according to any one of claims 1 to 4, wherein the heat-resistant resin layer is a polyimide film. 6. The metal-resin composite according to any one of claims 1 to 5, the metal foil is characterized in that it is a copper foil. (A) the main acid component is 3,3 ′, 4,
4'-biphenyltetracarboxylic dianhydride and 3,
3 ', 4,4'-benzophenonetetracarboxylic acid
Water, and the main amine component is 2,2-bis (4-
(4-aminophenoxy) phenyl) propane, 1,3
-Bis (3-aminophenoxy) benzene and dimethylphenyl
One or two selected from the group of enylene diamines
The above diamine and diaminosilo represented by the general formula (1)
100 parts by weight of a polyimide resin having a glass transition temperature soluble in an organic solvent comprising a xanse compound of 350 ° C. or lower,
(B) 5 to 100 parts by weight of an epoxy compound having at least two epoxy groups in one molecule, and (C) a compound having an active hydrogen group capable of reacting with the epoxy compound.
A resin adhesive solution containing 1 to 30 parts by weight as a main component is applied on a metal foil or a heat-resistant resin film, heated and dried, and then thermocompression-bonded to the heat-resistant resin film or metal foil, and further thermocompression bonding or more. A method for producing a metal / resin composite, comprising the step of post-curing at a temperature of: 8. (A) The main acid component is 3,3 ′, 4,
4'-biphenyltetracarboxylic dianhydride and 3,
3 ', 4,4'-benzophenonetetracarboxylic acid
Water, and the main amine component is 2,2-bis (4-
(4-aminophenoxy) phenyl) propane, 1,3
-Bis (3-aminophenoxy) benzene and dimethylphenyl
One or two selected from the group of enylene diamines
The above diamine and diaminosilo represented by the general formula (1)
100 parts by weight of a polyimide resin having a glass transition temperature soluble in an organic solvent comprising a xanse compound of 350 ° C. or lower,
(B) 5 to 100 parts by weight of an epoxy compound having at least two epoxy groups in one molecule, and (C) a compound having an active hydrogen group capable of reacting with the epoxy compound.
A resin adhesive solution containing 1 to 30 parts by weight as a main component is applied on a heat-resistant resin film, heated and dried, and then thermocompression-bonded to a metal foil, and then on the other surface of the heat-resistant resin film. Similarly, a method for producing a metal-resin composite, comprising the steps of applying a resin adhesive solution, heating and drying, thermocompression bonding a metal foil, and post-curing at a temperature equal to or higher than the thermocompression bonding. Embedded image (Wherein, R ₁ and R _{2 are} divalent aliphatic groups having 1 to 4 carbon atoms)
Or an aromatic group R ₃ , R ₄ , R ₅ , R ₆ : a monovalent aliphatic group or
Is an aromatic group k: 1 or 2) 9. The method according to claim 9, wherein (A) the main acid component is 3, 3 ′, 4,
4'-biphenyltetracarboxylic dianhydride and 3,
3 ', 4,4'-benzophenonetetracarboxylic acid
Water, and the main amine component is 2,2-bis (4-
(4-aminophenoxy) phenyl) propane, 1,3
-Bis (3-aminophenoxy) benzene and dimethylphenyl
One or two selected from the group of enylene diamines
The above diamine and diaminosilo represented by the general formula (1)
100 parts by weight of a polyimide resin having a glass transition temperature soluble in an organic solvent comprising a xanse compound of 350 ° C. or lower,
(B) 5 to 100 parts by weight of an epoxy compound having at least two epoxy groups in one molecule, and (C) a compound having an active hydrogen group capable of reacting with the epoxy compound.
A resin adhesive solution containing 1 to 30 parts by weight as a main component is coated on a metal foil, heated and dried, and then heat-resistant so that the resin adhesive solution surface of the two metal foils is on the inside. A method for producing a metal / resin composite, comprising a step of thermocompression bonding with a resin film interposed therebetween and post-curing at a temperature equal to or higher than the thermocompression bonding. 10. The method for producing a metal / resin composite according to claim 7 , wherein the thermocompression bonding temperature is 180 ° C. or lower. 11. The method for producing a metal-resin composite according to claim 7 , wherein the thermocompression bonding is continuously performed using a heated roll press or a belt press. 12. A flexible printed circuit board substrate using a metal-resin composite according to any one of claims 1-6.