JPH0834967A - Film adhesive having improved physical properties at high temperature and method for producing the same - Google Patents

Abstract

(57) [Summary] [Structure] (A) After mixing a polyamic acid having a low silicon content and a polyamic acid having a high silicon content in a molten state,
100 parts by weight of a polyimide resin, which is soluble in an organic solvent and has a glass transition temperature of 350 ° C. or lower, obtained by imidization, and (B) an epoxy compound having at least two epoxy groups in a molecule 5 to 100 Parts by weight, and (C) a compound having an active hydrogen group capable of reacting with the epoxy compound 0.1
A heat-resistant film adhesive and a method for producing the same, characterized by containing ~ 20 parts by weight as a main component. [Effect] It is possible to provide a highly reliable film adhesive having both heat resistance and adhesive workability. It has extremely high industrial utility value as a microelectronics material and semiconductor packaging material.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a film adhesive which has both heat resistance and low-temperature processability and is suitable for electronics, especially as a semiconductor mounting material, and has excellent adhesiveness to silicon substrates and metals, and a method for producing the same. Is.

[0002]

2. Description of the Related Art In recent years, while semiconductor chips have become larger due to higher functionality and larger capacity, the size of the package has not changed from the conventional one due to restrictions on printed circuit design, demand for miniaturization of electronic equipment, or a rather small external shape. Is being requested. In response to this tendency, some new mounting methods have been proposed for high density and high density mounting of semiconductor chips. One is a COL that mounts a chip on a lead frame without a die pad proposed for memory devices.
(Chip-on-lead) structure and LOC (lead-on-chip) structure in which leads are mounted on a chip, which is a development of the structure. On the other hand, the logic element has a multi-layered lead frame structure in which a power source and a ground are provided in different frames and a metal plate for heat dissipation is multi-layered. According to these, it is possible to rationalize the wiring in the chip and wire bonding, to speed up the signal by shortening the wiring, to dissipate heat generated due to the increase in power consumption, and to reduce the element size.

In this new mounting mode, there are bonding interfaces of the same kind and different materials such as a semiconductor chip and a lead frame, a lead frame and a plate, and lead frames, and the bonding reliability greatly affects the reliability of the device. . Not only the reliability of withstanding the process temperature at the time of assembling the element, but also the bonding reliability at the time of moisture absorption, heat and humidity. Further, the workability of bonding is also an important item.

Conventionally, a paste-like adhesive or a heat-resistant base material coated with an adhesive has been used for these adhesions. Epoxy resin-based, acrylic resin-based, and rubber-phenol resin-based thermosetting resins are used as adhesives, but there are many ionic impurities, heat curing requires high temperature and long time, and productivity is poor, heat curing It is hard to say that the requirements for a highly reliable adhesive such as a large amount of volatile components that contaminate leads and high hygroscopicity are satisfied, and no satisfactory material is found. There is a demand for the development of adhesives suitable for new mounting forms. One of such methods is a hot-melt type film adhesive using a polyimide resin (see JP-A-5-105850, 112760, 112761). A hot-melt type adhesive can be thermocompression-bonded to an adherend in a short time, and a heat-curing step after adhesion is not required, which is considered to greatly contribute to improvement in productivity and reliability. . However, since it is a hot-melt type, if the glass transition temperature of the adhesive resin is high, it takes a very high temperature for processing, and there is a great possibility that the adherend is thermally damaged. On the other hand, if the glass transition temperature is lowered in order to impart low-temperature processability, there is a problem that the heat resistance is lowered, and thus the reliability is lowered.

[0005]

DISCLOSURE OF THE INVENTION The present invention has been earnestly studied in order to obtain a film adhesive which can be bonded at a low temperature in a short time and is excellent in heat resistance. As a result, an epoxy compound and the epoxy compound are added to a polyimide resin having a specific structure. The present inventors have found that the above problems can be solved by adding a compound having an active hydrogen group capable of reacting with the compound, and have reached the present invention.

[0006]

The present invention provides a polyimide resin 100 having a glass transition temperature of 350 ° C. or lower and soluble in an organic solvent.
An adhesive resin component containing, by weight, 5 to 100 parts by weight of an epoxy compound having at least two epoxy groups in one molecule, and 0.1 to 20 parts by weight of a compound having an active hydrogen group capable of reacting with the epoxy compound. The present invention relates to a film adhesive having improved physical properties at high temperatures and a method for producing the same.

The component (A) polyimide resin, which is an essential component of the adhesive resin of the present invention, is obtained by mixing a polyamic acid having a low silicone content and a polyamic acid having a high silicone content in a solution state and then imidizing the mixture. Is characterized by. This is a mixed polyimide resin obtained by mixing two types of polyamic acid, which has high heat resistance, particularly excellent mechanical strength at the time of heat treatment, due to the low silicone content polyamic acid-derived portion having low water absorption and adhesiveness. It is characterized in that a trade-off characteristic is realized by allowing the portion derived from a high silicone content polyamic acid to have excellent modification characteristics. Furthermore, by mixing in the amic acid state and then imidizing, separation of the two components can be prevented and solvent solubility can be obtained.

More specifically, 4,4'-oxydiphthalic dianhydride, 3,3 ', 4,4' containing a mole of silicon diamine represented by the formula (1) and another mole of diamine as an amine component.
-Biphenyltetracarboxylic dianhydride, and 3,3 ', 4,4'
-0.02 ≦ a / (a + b) ≦ 0.10 in which one or two or more kinds of tetracarboxylic acid dianhydride c moles selected from the group of benzophenone tetracarboxylic acid dianhydride is used as an acid component
And 0.960 ≤ c / (a + b) ≤ 1.04 with a low silicone content of polyamic acid A, and 4,4'-oxydiphthalic acid containing d mole of silicon diamine represented by the formula (1) and other mole of diamine as an amine component. Acid dianhydride, 3,3 ', 4,4'-
Biphenyltetracarboxylic dianhydride, and 3,3 ', 4,4'-
0.20 ≦ d / (d + e) ≦ 0.70 containing f mole of one or more tetracarboxylic dianhydrides selected from the group of benzophenone tetracarboxylic dianhydride as an acid component
And 0.920≤f / (d + e) ≤1.10 with a high silicone content polyamic acid B in solution 0.12≤
It is a polyimide resin characterized by being manufactured by mixing so that (a + d) / (a + b + d + e) ≦ 0.50 and then imidizing.

[0009]

Embedded image (In the formula, k is an integer of 1 to 13)

More preferably, in the polyamic acid A, the other diamine component used in combination with the silicone diamine is represented by one or more kinds of diamine represented by the formula (2) and hmol of the diamine represented by the formula (3). And 1 or 2 or more kinds of diamines, and in the polyamic acid B, the other diamine component used in combination with the silicone diamine is one or more kinds of diamines represented by the formula (2) and a formula. One or two or more kinds of diamines represented by (3) are used, and 0.1 ≦ (h + j) / (i + k)
The polyimide resin is characterized in that ≦ 10.

[0011]

Embedded image

[0012]

Embedded image

The tetracarboxylic dianhydride used in the present invention is 4,4'-oxydiphthalic dianhydride, 3,3 ', 4,4'-biphenyltetracarboxylic, from the viewpoint of compatibility between solvent solubility and heat resistance. It is preferable to use acid dianhydride and 3,3 ′, 4,4′-benzophenone tetracarboxylic acid dianhydride. These tetracarboxylic dianhydrides may be used alone or in combination of two or more. Further, the tetracarboxylic dianhydride constituting the two types of polyamic acid to be mixed and the mole ratio of the components may be the same or different.

The silicone diamine represented by the formula (1) used in the present invention is α, ω-bis (3-aminopropyl) polydimethylsiloxane, and preferably k = 1 to 13, particularly k A value in the range of 4 to 10 is preferable from the viewpoint of glass transition temperature, adhesiveness and heat resistance. In addition, blending k = 1 and the above k = 4 to 10 is preferable especially in applications where importance is attached to adhesiveness.

The diamine represented by the general formula (2) is 2,2-
Bis (4- (4-aminophenoxy) phenyl) propane, 2,2-
Bis (4- (4-aminophenoxy) phenyl) hexafluoropropane, 2,2-bis (4-aminophenoxy) hexafluoropropane, bis-4- (4-aminophenoxy) phenyl sulfone, bis-4- (3 -Aminophenoxy) phenyl sulfone, 1,3-bis (3-aminophenoxy) benzene, 1,4-
Bis (3-aminophenoxy) benzene, 1,4-bis (4-aminophenoxy) benzene, 1,4-bis (3-aminophenoxy) benzene, 4,4′-diaminodiphenyl ether, 3,4 ′
-Diaminodiphenyl ether, 4,4'-diaminodiphenyl sulfone, 3,3'-diaminodiphenyl sulfone,
Examples include 4,4′-diaminodiphenylmethane and 4,4′-bis (4-aminophenoxy) biphenyl. Among them, diamines having an aminophenoxy structure are preferable in the application field where the adhesiveness is important.

The diamine represented by the general formula (3) is o-phenylenediamine, m-phenylenediamine, p-phenylenediamine, and their monoalkyl and dialkyl nuclear substitution products. Especially when importance is attached to heat resistance, a diamine having a p-phenylenediamine skeleton is preferable. Amount ratio of diamines represented by formulas (2) and (3) (h + j) / (i +
k) is preferably in the range of 0.1 ≦ (h + j) / (i + k) ≦ 10 from the viewpoint of workability balance such as solubility, heat resistance and adhesiveness. Outside of this range, the solubility of the solvent is lost and the effect of improving heat resistance is not recognized, which is not preferable.

The constitutional molar ratio of these diamine and acid is 0.02 ≦ a / in the case of polyamic acid having a low silicone content.
(A + b) ≦ 0.10 and 0.960 ≦ c / (a + b) ≦
Must be 1.04. If the molar ratio of the silicone diamine is less than 0.02, the solvent solubility of the obtained mixed polyimide resin is lost, and if it exceeds 0.10, the heat resistance of the obtained mixed polyimide resin is unfavorable. If the acid / amine molar ratio deviates from the above range, the molecular weight of the obtained polyimide resin decreases, and the purpose of bearing mechanical strength is not achieved, which is not preferable.

For polyamic acids with high silicone content, 0.20≤d / (d + e) ≤0.70 and 0.920≤f /
It must be (d + e) ≦ 1.10. When the molar ratio of the silicone diamine is less than 0.20, it becomes impossible to express the excellent properties of silicone modification in the obtained mixed polyimide resin, and when it exceeds 0.70, the mechanical strength of the obtained mixed polyimide resin is significantly reduced, which is preferable. Absent. If the acid / amine molar ratio deviates from the above range, the molecular weight of the obtained polyimide resin decreases,
It is not preferable because the heat resistance of the mixed polyimide resin is significantly lowered.

Furthermore, the molar ratio of the two polyamic acids to the total silicone diamine is 0.12≤ (a + d) / (a +
b + d + e) ≦ 0.50, more preferably 0.20 ≦ (a +
It is preferable to mix d) / (a + b + d + e) ≦ 0.50. It is important that the amount ratio is within the above range, and if the molar ratio of the silicone diamine is less than 0.12, the characteristics such as low water absorption, solubility and adhesiveness, which are excellent characteristics of silicone modification, do not appear, and it exceeds 0.50. Then, the mechanical strength at high temperature is remarkably reduced, and a problem occurs in heat resistance.

The equivalent ratio of the acid component and the amine component in the polycondensation reaction is an important factor that determines the molecular weight of the polyamic acid obtained. It is well known that there is a correlation between polymer molecular weight and physical properties, especially number average molecular weight and mechanical properties. The larger the number average molecular weight, the better the mechanical properties. Therefore, in order to obtain practically excellent strength, it is necessary that the polymer has a high molecular weight to some extent. In the present invention,
The equivalent ratio r of the acid component and the amine component is more preferably 0.900 ≤ r ≤ 1.060, and more preferably 0.975 ≤ r ≤ 1.025. However, r = [equivalent number of all acid components] / [equivalent number of all amine components]. r is 0.
If it is less than 900, the molecular weight is low and it becomes brittle, so the adhesive strength becomes weak. On the other hand, if it exceeds 1.06, unreacted carboxylic acid may be decarboxylated during heating to cause gas generation and foaming, which is not preferable.

In the present invention, addition of a dicarboxylic acid anhydride or a monoamine for controlling the molecular weight of the polyimide resin is not particularly hindered if the acid / amine molar ratio is within the above range.

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 (DMF), N, N-dimethylacetamide (DMA
C), N-methyl-2-pyrrolidone (NMP), tetrahydrofuran (THF), diglyme, cyclohexanone,
1,4-dioxane (1,4-DO) and the like. The aprotic polar solvent may be used alone or in combination of two or more. 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 30% by weight or less. This is because if the amount of the nonpolar solvent is 30% by weight or more, the solubility of the solvent may decrease and polyamic acid may precipitate. The reaction of the tetracarboxylic acid dianhydride and the diamine is carried out by dissolving the well-dried diamine component in the dehydrated and purified reaction solvent described above, and the ring closure rate of 98%, more preferably 99% or more of the well-dried tetracarboxylic acid dianhydride. Anhydrous is added to drive the reaction.

The polyamic acid solution thus obtained is subsequently heated and dehydrated in an organic solvent to form an imidized polyimide. Since the water generated by the imidization reaction interferes with the ring-closing reaction, an organic solvent that is not compatible with water is added to the system to azeotropically evaporate it and use a device such as a Dean-Stark tube to remove it from the system. To discharge. Dichlorobenzene is known as an organic solvent which is incompatible with water, but for electronics use, the aromatic hydrocarbon is preferably used since chlorine components may be mixed therein. Further, the use of compounds such as acetic anhydride, β-picoline and pyridine as a catalyst for the imidization reaction is not hindered.

In the present invention, the higher the degree of imide ring closure, the better, and if the imidization ratio is low, imidization occurs due to heat during use and water is not generated, which is not preferable. Therefore, 95% or more, more preferably 98% or more. It is desirable that the imidization ratio of is achieved.

In the present invention, an epoxy compound or a compound having an active hydrogen group capable of reacting with the epoxy compound may be added to the obtained polyimide solution as it is, and a resin varnish may be prepared and coated on a support. It is preferable that the polyimide solution is put into a poor solvent to reprecipitate and precipitate the polyimide resin to remove unreacted monomers and to perform purification. A purified and dried polyimide resin, an epoxy compound, and a compound having an active hydrogen group capable of reacting with the epoxy compound are dissolved in an organic solvent to prepare a coating varnish. The solvent used at this time may be the same as the reaction solvent, but it is preferable to select a solvent having a low boiling point, preferably a boiling point of 200 ° C. or less, in consideration of workability in the coating and drying step. As a solvent of 200 ℃ or less, in the present invention, as a ketone solvent, acetone, methyl ethyl ketone, methyl isobutyl ketone, cyclopentanone, cyclohexanone, as an ether solvent, 1,4-dioxane, tetrahydrofuran, diglyme, as an amide solvent , N, N-dimethylformamide, N, N-dimethylacetamide. These solvents may be used alone or in combination of two or more.

The component (B) epoxy compound used in the adhesive resin of the present invention is not particularly limited as long as it has at least two epoxy groups in one molecule, but it may be used as a solvent for the polyimide resin. Those having good solubility are preferred. Examples thereof include bisphenol A type diglycidyl ether, bisphenol F type diglycidyl ether, phenol novolac type epoxy resin, and biphenyl type epoxy resin.

The compounding amount of the epoxy compound is the component (A).
5-100 parts by weight per 100 parts by weight of polyimide resin, especially 1
It is preferably in the range of 0 to 70 parts by weight. If it is less than 5 parts by weight, the effect of adding an uncured epoxy compound and lowering the softening temperature of the resin composition to improve low-temperature processability is unlikely to appear, and if it exceeds 100 parts by weight, the heat resistance of the polyimide resin is impaired, which is preferable. Absent.

Component (C) used in the adhesive resin of the present invention is a compound having an active hydrogen group capable of reacting with the epoxy compound, and is a polyimide resin of component (A) or component (B).
It is preferable that the compatibility with the epoxy compound and the solubility of the polyimide resin in the solvent are good. For example, resole, novolac, amino compound and the like can be mentioned. The mixing ratio of the component (C) is 0.1 to 20 parts by weight, more preferably 0.5 to 10 parts by weight, based on 100 parts by weight of the polyimide resin of the component (A). If it is less than 0.1 parts by weight, it is difficult to control the resin flow when the elastic modulus of the resin at high temperature is lowered, and when the resin composition is used for bonding, the adhesion with the adherend is improved. The effect that causes it does not appear. If it exceeds 20 parts by weight, the heat resistance of the resin composition is impaired, which is not preferable.

The heat-resistant resin composition of the present invention may contain a fine inorganic filler as long as the processability and heat resistance thereof are not impaired.

Various additives such as a leveling agent, a leveling agent and a defoaming agent for providing surface smoothness can be added to the resin varnish as required. Further, an aromatic hydrocarbon solvent can be used within a range in which the solvent is uniformly dissolved in order to control the evaporation rate of the solvent.

In the present invention, the resin varnish is used as a film adhesive, which is obtained by casting or coating a resin varnish. For example, a heat-resistant film substrate is used as a support, and a film layer is similarly formed on one side or both sides thereof. To form a film adhesive with the support, rolls, metal sheets,
Form a film on a release sheet such as a polyester sheet with a flow coater, roll coater, etc.,
It can be obtained by a method such as heating, drying and peeling to obtain a film adhesive.

The heat-resistant film base material used in the present invention is that the polyimide resin film has a small coefficient of thermal expansion and is excellent in dimensional stability with respect to temperature changes, is flexible and easy to handle, and is made of the resin of the present invention. Is preferable because it has excellent adhesion. In particular, a polyimide resin having a glass transition temperature of 350 ° C or higher is excellent in workability and stability in the step of drying the coating varnish.

For coating and drying the resin varnish, an apparatus in which coating equipment such as a flow coater or roll coater and a hot air drying oven are combined can be used. After coating the resin varnish on the support, the resin varnish is introduced into a hot air drying oven and dried at a temperature and an air volume sufficient to vaporize the solvent of the varnish.

The method of using the film adhesive of the present invention is not particularly limited, but the film adhesive can be used as an adhesive tape by thermocompression bonding with a heat block that is cut into a predetermined shape and heated. .

[0035]

The film adhesive of the present invention comprises 4,4'-oxydiphthalic dianhydride, 3,3 ', with a mole of silicon diamine represented by the formula (1) and another mole of diamine as an amine component. Four,
4'-biphenyltetracarboxylic dianhydride, 3,3 ', 4,4'-
One or two or more kinds of tetracarboxylic acid dianhydride c moles selected from the group of benzophenone tetracarboxylic acid dianhydride as an acid component, and 0.02 ≦ a / (a + b) ≦ 0.1
0, 0.960 ≦ c / (a + b) ≦ 1.04 reacted with polyamic acid A and silicon diamine d represented by the formula (1)
Mole and other diamine e mole as an amine component, 4,4'-oxydiphthalic dianhydride, 3,3 ', 4,4'-biphenyltetracarboxylic dianhydride, 3,3', 4,4 ' -One or two or more kinds of tetracarboxylic acid dianhydride selected from the group of benzophenone tetracarboxylic acid dianhydride as an acid component,
And 0.20 ≦ d / (d + e) ≦ 0.70, 0.920 ≦ f / (d +
e) with polyamic acid B reacted in a ratio of ≦ 1.10, 0.12
≦ (a + d) / (a + b + d + e) ≦ 0.50 mixed and imidized, soluble in organic solvent and having glass transition temperature
(B) for 100 parts by weight of polyimide resin below 350 ° C
Containing 5 to 100 parts by weight of an epoxy compound having at least two epoxy groups in one molecule and (C) 0.1 to 20 parts by weight of a compound having an active hydrogen group capable of reacting with the epoxy compound as main components It is characterized by being The apparent glass transition temperature of this resin is lower than the glass transition temperature of the main component polyimide resin, and the low temperature processability is improved. On the other hand, the adhesive strength in the temperature range higher than the glass transition temperature is higher than that of the polyimide resin, and the physical properties in the high temperature area are improved such that peeling is not observed even when a thermal shock such as IR reflow is applied. Although the detailed mechanism for this peculiar phenomenon is not clear yet, the low molecular weight product obtained by reacting the epoxy compound and the compound having an active hydrogen group capable of reacting with the epoxy compound is a polyimide resin having a specific structure. On the other hand, it acts as a plasticizer and lowers the elastic modulus in a temperature range lower than the glass transition temperature of the polyimide resin, thus improving workability at low temperature such as adhesiveness and processability. On the other hand, in a temperature range higher than the glass transition temperature, it is considered that a three-dimensional network structure is formed by the applied heat and the fluidity of the polyimide resin is lowered, and thus the heat resistance of the polyimide resin is maintained or improved. By the above mechanism, both low temperature processability and heat resistance reliability at high temperature can be achieved. Further, it can be bonded in an extremely short time as compared with a thermosetting adhesive which involves a chemical reaction. By processing into a tape shape, the workability of bonding and the dimensional accuracy of the bonded portion can be made excellent. The present invention is described in detail below with reference to examples, but the present invention is not limited to these examples.

[0036]

【Example】

(Synthesis of Polyimide Resin PI-1) (1) Preparation of Polyamic Acid A. 213 g of dehydrated and refined NMP was put into a four-necked flask equipped with a dry nitrogen gas introduction tube, a cooler, a thermometer, and a stirrer, and nitrogen gas was flown. While 1
Stir vigorously for 0 minutes. Next, 2,2-bis (4- (4-aminophenoxy) phenyl) propane (BAPP) 25.4519 g
(0.0620 mol) and 2,5-dimethyl-p-phenylenediamine (DPX) 4.2221 g (0.0310 mol) and α, ω-bis (3-aminopropyl) polydimethylsiloxane (APPS) 5.85
90 g (average molecular weight 837, 0.0070 mol,) was added and the system was adjusted to 6
Heat to 0 ° C and stir until uniform. After uniform dissolution, the system was cooled to 5 ° C in an ice-water bath, and 31.0222 g (0.1000 mol) of 4,4'-oxydiphthalic dianhydride was kept in powder form.
The mixture was added over a period of 1 minute, and stirring was continued for 5 hours to obtain a polyamic acid solution. During this time, the flask was kept at 5 ° C.

(2) Preparation of polyamic acid B: Similarly to polyamic acid A, 303.6 g of NMP is vigorously stirred for 10 minutes while flowing nitrogen gas. Next, 1,2-bis (4- (4-aminophenoxy) phenyl) propane 11.4944 g (0.0280 mol) and 2,5-dimethyl-p-phenylenediamine 1.9067 g
(0.0140 mol) and α, ω-bis (3-aminopropyl) polydimethylsiloxane 48.5460 g (average molecular weight 837, 0.0580 mol) are added, and the system is heated to 60 ° C. and stirred until uniform. After uniform dissolution, the system was cooled to 5 ° C in an ice water bath,
-31.0222 g (0.1000 mol) of oxydiphthalic acid dianhydride was added in powder form over 10 minutes, and then stirring was continued for 5 hours. During this time, the flask was kept at 5 ° C.

(3) Preparation of polyimide resin: Polyamic acid A and polyamic acid B are weighed in the same weight and placed in a flask. At this time, the average amount of silicone diamine is 32.5 mol% based on all amine components. The nitrogen gas introduction tube and the condenser were removed, a Dean-Stark tube filled with xylene was attached to the flask, and xylene was added to the system. The ice water bath was replaced with an oil bath to heat the system and remove the generated water outside the system. Four
After heating for an hour, generation of water from the system was not observed. After cooling, this reaction solution was poured into a large amount of methanol to precipitate a polyimide resin. After filtering the solids, 80
It was dried under reduced pressure at ℃ for 12 hours to obtain a solid resin. When the infrared absorption spectrum was measured by the KBr tablet method, an absorption of 5.6 μm derived from a cyclic imide bond was observed, but an absorption of 6.06 μm derived from an amide bond was not observed, and this resin was almost 100%. It was confirmed that it was imidized.
At this time, the molar ratio of acid and amine is b = h + i,
a / (a + b) = 0.07, c / (a + b) = 1, e = j +
k, d / (d + e) = 0.58, (h + j) / (i + k) =
2, g / (d + e) = 1, (a + d) / (a + b + d +
e) = 0.325. It was confirmed that the polyimide resin thus obtained was well soluble in dimethylformamide (DMF), 1,4-dioxane (1,4-DO) and tetrahydrofuran (THF). Glass transition temperature 166 ℃,
The tensile elastic modulus was 215 kgf / mm ² .

(Synthesis of Polyimide Resin PI-2) A polyimide resin PI-2 was obtained in the same manner as the synthesis of the polyimide resin PI-1. The evaluation results obtained for these polyimide resins are shown in Table 1.

[0040]

[Table 1]

APB and BPDA in the column of monomer represent 1,3-bis (3-aminophenoxy) benzene and 3,3 ', 4,4'-biphenyltetracarboxylic dianhydride, respectively.

S in the solubility column indicates that the compound is soluble in the corresponding solvent. The glass transition temperature was determined by DSC measurement. The tensile test was performed at room temperature and a tensile speed of 5 mm / min.

(Example 1) (Preparation of coating varnish) 100 g of polyimide resin PI-1 and 355 g of DMF were placed in a glass flask and thoroughly stirred at room temperature to completely dissolve the polyimide. After uniform dissolution, bisphenol A type epoxy compound (Epicoat 8
28, 40 g of Yuka Shell Epoxy Co., Ltd.) was added and stirred at room temperature for 2 hours. After confirming that it has dissolved uniformly, resol resin (PR-50781, Sumitomo Dures
5 g (manufactured by K.K.) was gradually added with stirring. Continue 2
The mixture was stirred for a time to prepare a heat resistant resin solution. The solution composition did not gel even after standing at room temperature for 10 days and remained in a uniform solution state.

(Production of Heat-Resistant Film Adhesive) The above-mentioned varnish was applied to one surface of a polyimide film (trade name Upilex SGA, thickness 50 μm, Ube Industries, Ltd.) with a reverse roll coater, and the thickness of the adhesive layer was adjusted. An adhesive tape of 30 μm was obtained. Drying temperature is up to 200 ° C and drying time is 15
It was a minute. A test piece was prepared by thermocompression-bonding this adhesive tape to a 42 alloy plate (250 ° C. for 2 seconds, releasing the pressure, and annealing at 250 ° C. for 30 seconds. The pressure applied to the adhesive surface is the gauge pressure and the adhesive area. The result of the calculation was 4 kgf / cm ^2. ), and the results of measuring the 180 degree peel strength with a tensile tester are shown in Table 2. The adhesive strength is a 180 degree peel strength measured at room temperature and 240 ° C. after being treated with a normal state and a pressure cooker (125 ° C., 48 hours, 100% saturation) (pulling speed 50 mm / min). On the fracture surface of the test piece, the adhesive resin layer was cohesively broken, and no foaming was observed.

Example 2 The varnish of Example 1 was biaxially stretched polyester film (trade name: diamond foil, thickness 50 μm, manufactured by Mitsubishi Rayon Co., Ltd.) with a reverse roll coater.
Apply to, peel off from the polyester film after drying, 30
A uniform monolayer film adhesive without a support having a thickness of μm was obtained. Peeling was easy and there was no particular problem. The results of adhesion to 42 alloy as in Example 1 are shown in Table 2.

(Examples 3 to 5) In the same manner as in Examples 1 and 2, coating varnishes were prepared with the formulations shown in Table 2 to obtain film adhesives. Table 2 shows the obtained evaluation results.

[0047]

[Table 2]

S in the solubility column indicates that the compound is soluble in the corresponding solvent. The glass transition temperature was determined by DSC measurement. The tensile test was performed at room temperature and a tensile speed of 5 mm / min. Regarding the component (B) epoxy compound used, YX
-4000H is a biphenyl type epoxy compound Epicoat YX-4000H, manufactured by Yuka Shell Epoxy Co., Ltd., EOC
N-1020 is a phenol novolac type epoxy compound EOCN-1020, manufactured by Nippon Kayaku Co., Ltd., respectively. Regarding the component (C) used, PR-5078
1, 175, 53647, 22193 are Sumitomo Dures
A product manufactured by Co., Ltd. was used.

(Comparative Examples 1 and 2) Polyimide resin PI-1
And PI-2 are polyimide films (Upilex)
Was coated on one side to obtain a film adhesive. The adhesive strength with 42 alloy was measured in the same manner as in the example, and the results are shown in Table 3.

[0050]

[Table 3]

(Comparative Example 3) Polyimide resin PI-1, 10
The adhesive strength of the adhesive tape obtained from the resin prepared by adjusting only 0 g and PR-50781, 20 g was measured in the same manner as in Examples, and the results are shown in Table 3.

(Comparative Example 4) Polyimide resin PI-1, 10
The adhesive strength of an adhesive tape obtained from a resin prepared only with 0 g and Epicoat 828, 20 g was measured in the same manner as in the example, and the results are shown in Table 3.

From the results shown in Tables 2 and 3, the adhesive strength of the adhesive tape of Comparative Example after being treated with the pressure cooker was as follows:
It is markedly lower than that of the tapes obtained from the resin compositions of Examples. The above examples show that the present invention can provide a film adhesive having excellent heat resistance and molding processability, which can prevent the adhesive strength from significantly decreasing under heat of moisture absorption.

[0054]

According to the present invention, it is possible to provide a highly reliable film adhesive having both heat resistance and molding processability. Since it is soluble in a low boiling point solvent, it is possible to almost completely eliminate the residual solvent, and since it has already been imidized, a high temperature process for imidization is not required during processing and no water is generated. Since it can be used as a tack-free film, it is very effective when continuous workability and a clean environment are required. Therefore, it is industrially extremely useful as a material for electronics that requires high reliability and heat resistance.

Claims (5)

[Claims] (A) A mol of silicon diamine represented by the formula (1) and b mol of another diamine as an amine component,
4'-oxydiphthalic dianhydride, 3,3 ', 4,4'-biphenyltetracarboxylic dianhydride, selected from the group of 3,3', 4,4'-benzophenone tetracarboxylic dianhydride One type or two or more types of tetracarboxylic acid dianhydride (c mole) as an acid component, and 0.02 ≦ a / (a + b) ≦ 0.10, 0.960 ≦ c /
(A + b) ≦ 1.04 reacted with polyamic acid A,
4,4'-oxydiphthalic acid dianhydride, 3,3 ', 4,4'-biphenyltetracarboxylic dianhydride containing d mol of silicon diamine represented by the formula (1) and e mol of other diamine as amine components. , 3,3 ', 4,4'-benzophenone tetracarboxylic acid dianhydride selected from the group of 1 or 2 or more tetracarboxylic acid dianhydrides as an acid component, and 0.20 ≤ d /
(D + e) ≦ 0.70, 0.920 ≦ f / (d + e) ≦ 1.10 and polyamic acid B reacted in the ratio of 0.12 ≦ (a + d) /
(A + b + d + e) ≦ 0.50 mixed and imidized, 100 parts by weight of an organic solvent-soluble polyimide resin having a glass transition temperature of 350 ° C. or lower, and (B) at least two epoxy groups in one molecule. Physical properties at high temperature, characterized by containing 5 to 100 parts by weight of the epoxy compound and (C) 0.1 to 20 parts by weight of a compound having an active hydrogen group capable of reacting with the epoxy compound as main components. An improved film adhesive. Embedded image (K: integer from 1 to 13) 2. The polyimide resin of component (A),
The other diamine in the polyamic acid A is one or more kinds of diamines represented by the formula (2) and the formula (3).
And 1 or 2 or more types of diamines represented by the formula (2), and the other diamine in the polyamic acid B is represented by the formula (2): One or two or more kinds of diamines are used, and 0.1 ≦ (h + j) / (i + k) ≦ 10
The film adhesive with improved physical properties at high temperature according to claim 1. Embedded image Embedded image 3. (A) A mol of silicon diamine represented by the formula (1) and b mol of another diamine as an amine component,
4'-oxydiphthalic dianhydride, 3,3 ', 4,4'-biphenyltetracarboxylic dianhydride, selected from the group of 3,3', 4,4'-benzophenone tetracarboxylic dianhydride One type or two or more types of tetracarboxylic acid dianhydride (c mole) as an acid component, and 0.02 ≦ a / (a + b) ≦ 0.10, 0.960 ≦ c /
(A + b) ≦ 1.04 reacted with polyamic acid A,
4,4'-oxydiphthalic acid dianhydride, 3,3 ', 4,4'-biphenyltetracarboxylic dianhydride containing d mol of silicon diamine represented by the formula (1) and e mol of other diamine as amine components. , 3,3 ', 4,4'-benzophenone tetracarboxylic acid dianhydride selected from the group of 1 or 2 or more tetracarboxylic acid dianhydrides as an acid component, and 0.20 ≤ d /
(D + e) ≦ 0.70, 0.920 ≦ f / (d + e) ≦ 1.10 and polyamic acid B reacted in the ratio of 0.12 ≦ (a + d) /
At least 2 epoxies per molecule (B) per 100 parts by weight of a polyimide resin having a glass transition temperature of 350 ° C. or lower, which is imidized by mixing (a + b + d + e) ≦ 0.50. Epoxy compound having a group 5
To 100 parts by weight and (C) 0.1 to 20 parts by weight of a compound having an active hydrogen group capable of reacting with the epoxy compound as a main component, a solution of a resin composition is cast on one side or both sides of a support. A method for producing a film adhesive having improved physical properties at high temperature, which comprises molding. 4. The polyimide resin of component (A),
The other diamine in the polyamic acid A is one or more kinds of diamines represented by the formula (2) and the formula (3).
And 1 or 2 or more types of diamines represented by the formula (2), and the other diamine in the polyamic acid B is represented by the formula (2): One or two or more kinds of diamines are used, and 0.1 ≦ (h + j) / (i + k) ≦ 10
4. The method for producing a film adhesive having improved physical properties at high temperature according to claim 3. 5. The physical property at high temperature according to claim 3 or 4, which is obtained by casting on a support using an organic solvent having a boiling point of 200 ° C. or lower, drying and peeling from the support. Of producing a film adhesive having a high temperature.