JP2006124637A - Polyimide adhesive composition and polyimide adhesive tape - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a polyimide adhesive composition which excels in insulating properties and heat resistance, improves high temperature adhesion properties, and excels in adhesion properties to a coating layer of mutually different materials formed on a substrate layer, and a polyimide adhesive tape using this polyimide adhesive composition. <P>SOLUTION: The polyimide adhesive composition is constituted of (A) a tetracarboxylic dianhydride, (B) a diamine, (C) a diamine containing a siloxane structure, (D) a polyamino compound of any one kind or in a mixed form of two or more kinds selected from the group consisting of a triamine and a tetraamine, and (E) 3,4-diaminobenzoic acid. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a polyimide adhesive composition and a polyimide adhesive tape using the same, and more specifically, it has excellent insulation and thermal resistance, and improved high-temperature adhesive properties, and is formed on a base material layer. The present invention relates to a polyimide adhesive composition excellent in adhesive properties with different coating layers, and a polyimide adhesive tape using the same.

  In general, an adhesive tape for electronic components is used for bonding between peripheral components of a lead frame constituting a semiconductor device, for example, a lead pin, a semiconductor mounting substrate, a heat sink, and a semiconductor chip itself, and is an FPC (Flexible Printed Circuit). ) Adhesive tapes with increased adhesion to copper foil suitable for original plate applications and TAB (Tape Automated bonding) original plate tapes are also included.

  Such electronic component tapes include lead frame fixing adhesive tapes, lead frame-semiconductor chip adhesive tapes, lead frame die pad adhesive tapes, and the like.

  In particular, the adhesive tape for LOC (Lead on Chip) package is a high temperature process in which the lead frame is bonded to one side of the tape and the chip is bonded to the other side of the tape. (Temperature condition) In the early days of the introduction of the LOC package, tape was attached to the lead frame and chip in a high temperature process around 400 ° C., but the temperature of the bonding process was reduced to reduce the yield loss due to the thermal stress of the semiconductor package. Efforts are being made to gradually lower it, and in recent years, bonding is performed at around 300 ° C. The temperature of such an adhesion process is expected to continue to decrease.

  If a thermosetting resin such as a normal epoxy resin is used in this process, the adhesive layer on the other side is simultaneously cured during the process of adhering the adhesive layer on one side of the tape to the lead frame at a high temperature. The bonding process becomes impossible. Therefore, a thermoplastic adhesive material having high temperature melting characteristics is required.

  For this reason, the polyimide resin is excellent not only in the stability of the imide ring structure itself but also in the heat resistance because of the large packing density between the chains due to the linear structure of the main chain. In addition to this, polyimide resins are used in various applications such as electronic materials, adhesives, coatings, composite materials, fibers and film materials due to their excellent chemical resistance, electrical insulation and mechanical properties. . However, polyimides mainly applied for film use have a glass transition temperature of 300 ° C. or higher, and hardly exhibit fluidity at high temperatures, so that there is a limit to utilization for adhesive applications.

  Therefore, in order to utilize polyimide for adhesives, the physical properties of polyimide must be improved, and such efforts are continuously made. According to a known method, a polyimide resin is reacted with a tetracarboxylic dianhydride and a diamine in an organic solvent to produce a polyimide precursor, polyamic acid, and then thermally or chemically condensed to be imidized.

  Here, triamine or tetraamine is introduced into diamine, which is a conventional amine component, and the linear structure of polyimide is synthesized with a three-dimensional structure by gelation, thereby simultaneously improving heat resistance and mechanical properties. A method has been proposed (see Patent Document 1). However, it has been pointed out that the produced adhesive using the polyimide resin has insufficient film flexibility and has low processing properties due to a decrease in solubility of polyamic acid and polyimide due to gelation. Accordingly, the method of adding a triamine or tetraamine polyamino compound component to the diamine still has a problem with respect to the high temperature fluidity or adhesive strength of the adhesive.

  As another method, during the production process of polyimide, dianhydride or diamine has two or more phenyl rings, and ether functional groups (—O—) are introduced between the phenyl rings to reduce heat resistance at high temperatures. There has been proposed a method for improving the high-temperature adhesive properties by providing fluidity at high temperatures by having molecular movement. However, since the heat resistance of the adhesive is reduced, the high temperature stability is not ensured, and the reliability required in the semiconductor assembly process during the high temperature process cannot be ensured. Moreover, recently, a bonding process temperature of 300 ° C. or lower is required, but there is a disadvantage that the bonding process property cannot be secured under such conditions.

  Therefore, in order to apply polyimide to adhesive tapes for electronic components that can be bonded at a lower temperature, we developed a new adhesive that can overcome the general physical properties of conventional polyimide compositions. There must be.

In particular, in the case of an adhesive tape for LOC package, one surface is bonded to a nickel iron alloy or copper metal lead frame, and the other surface is bonded to a polymer insulating coating film of a semiconductor chip, so that base materials of different materials are used. There are technical difficulties that must be satisfied simultaneously with the adhesive properties to the layers.
US Pat. No. 5,231,162

  Therefore, as a result of making efforts to provide a novel polyimide adhesive or adhesive tape excellent in the high-temperature bonding process, the present inventor, during the process of reacting dianhydride and diamine with an organic solvent, Polyamide compound containing aliphatic structure siloxane group, triamine and tetraamine, and 3,4-diaminobenzoic acid are added to the component, and the content of the acid component and amine component is adjusted to adjust the composition for polyimide adhesive As a result, the packing density between the main chains of the three-dimensional structure polyimide, where the linear structure between the polyimide main chains is broken, decreases, the free volume of molecular units increases, and the movement of the chains at high temperatures. Of the different materials formed on the base material layer at 300 ° C and 350 ° C. By confirming that the excellent adhesion to computing layer from the composition, and have completed the present invention.

  The objective of this invention is providing the composition for polyimide adhesives suitable for a high temperature adhesion process.

  Another object of the present invention is to provide a method for producing a polyimide using the polyimide adhesive composition.

  Another object of the present invention is to provide a polyimide adhesive tape using an adhesive liquid containing the produced polyimide.

  In order to solve the above problems, according to one aspect of the present invention, one or more selected from the group consisting of tetracarboxylic dianhydride, diamine, diamine containing a siloxane structure, triamine, and tetraamine The composition for polyimide adhesives which consists of a polyamino compound of this mixed form, and 3, 4- diaminobenzoic acid is provided.

  The composition for polyimide adhesives of this invention is (B) diamine 60-98 mol, (C) diamine 0.05-40 mol containing (C) siloxane structure with respect to 100 mol of (A) tetracarboxylic dianhydride, ( D) It is composed of 0.01 to 5 mol of a polyamino compound and 0.03 to 10 mol of (E) 3,4-diaminobenzoic acid.

  The polyimide adhesive composition may comprise (B) a diamine, (C) a diamine containing a siloxane structure, (D) a polyamino compound, and (A) 100 mol of the tetracarboxylic dianhydride acid component. E) The total amine component including 3,4-diaminobenzoic acid is more preferably 101 to 106 mol.

  In addition, the present invention, the polyimide adhesive composition is charged in an organic solvent and stirred under a nitrogen atmosphere, reacted at 100 ° C. or lower for 1 to 10 hours to produce a polyamic acid that is a polyimide precursor, Provided is a method for producing a polyimide obtained by applying or coating the polyamic acid on a substrate and then thermally imidizing it at a temperature of 250 to 500 ° C.

  The polyimide produced by the above production method preferably has a weight average molecular weight of 10,000 to 200,000 in order to satisfy the mechanical strength, heat resistance and adhesive properties at the same time.

  The present invention relates to a heat-resistant base film and a polyimide adhesive prepared by dissolving the prepared polyimide in an organic solvent so that the solid content is 15 to 25% by weight. Provided is a polyimide adhesive tape comprising a polyimide adhesive layer formed by applying and drying on one side or both sides.

  In this case, a polyimide film is most preferable as the heat-resistant base film.

  The composition for polyimide adhesive of the present invention and the polyimide adhesive using the same have improved adhesive properties in the high-temperature bonding process, and the high performance of nickel-iron alloy, copper-based metal lead frame and semiconductor chip at 300 ° C. and 350 ° C. Due to its excellent adhesive property to the molecular insulating coating film, it is useful as an adhesive tape for electronic parts, particularly a double-sided tape for LOC package.

  Hereinafter, the present invention will be described in detail.

  The polyimide adhesive composition of the present invention comprises (A) at least one tetracarboxylic dianhydride represented by the following chemical formula 1, and (B) at least one diamine represented by the following chemical formula 2, (C) any one selected from the group consisting of at least one diamine having a siloxane structure represented by the following chemical formula 3 and (D) a triamine represented by the following chemical formula 4 and a tetraamine represented by the chemical formula 5, or It comprises at least one or more of polyamino compounds in a mixed form of two or more and (E) 3,4-diaminobenzoic acid represented by the following chemical formula 6.

  In the formula, X represents a divalent functional group.

  More specifically, among the tetracarboxylic dianhydrides represented by the chemical formula 1, the X is selected from the compound represented by the following chemical formula 1a and the compound represented by the following chemical formula 1b. It consists of any one selected compound (X2), and the molar fraction of X1 and X2 is in the range of 1: 0 to 0.5: 0.5.

  At this time, the structure of X1 is mainly associated with the adhesive properties and high temperature fluidity of the polyimide adhesive, and the structure of X2 is mainly associated with the heat resistance and high temperature reliability of the polyimide adhesive.

  If the molar fraction of X1 and X2 is in the range of 1: 0 to 0.5: 0.50, the adhesive has flow characteristics during the high temperature bonding process and has a basic adhesive force with the substrate. However, if the molar fraction of X1 and X2 is in the range of 0.5: 0.5 to 0: 1, the adhesive properties of the adhesive deteriorate.

  In formula, m shows the integer of 1-10.

  In the formula, Y represents a divalent functional group.

  The diamine represented by the chemical formula 2 functions to adjust the heat resistance and fluidity of the polyimide adhesive, and two or more diamines having an appropriate structure can be used in combination according to the required physical properties. At this time, the diamine is preferably used in an amount of 60 to 98 mol with respect to 100 mol of the tetracarboxylic dianhydride represented by the chemical formula 1. If the amount of diamine used is less than 60 mol, the molecular weight of the polyimide decreases and the production cost increases, and if the amount of diamine used exceeds 98 mol, the flow characteristics and the base material Adhesive properties are reduced.

  More specifically, the Y is at least one selected from the group of compounds represented by Formula 2a.

In the formula, R ₄ represents an alkyl group having 1 to 20 carbon atoms, and n ′ represents an integer of 1 to 20.

  The diamine having a siloxane structure represented by Chemical Formula 3 is associated with the flow characteristics of the polyimide adhesive and the adhesive strength with the substrate during the high temperature process, and has a function of adjusting the flexibility and solubility of the polyimide. When a polyamino compound is added to form a three-dimensional network structure, the polyamino compound serves to prevent precipitation of the polymer or decrease in solubility due to gelation. At this time, it is preferable to use 0.05 to 40 moles of the diamine having a siloxane structure with respect to 100 moles of the tetracarboxylic dianhydride represented by Chemical Formula 1. If the amount of diamine containing a siloxane structure is less than 0.05 mol, the stability of the viscosity and solubility side of the polyimide polymer due to gelation will be reduced during polymerization, and the adhesive properties with the substrate will be reduced. If the amount of the diamine containing a siloxane structure is more than 40 mol, there is a drawback that the molecular weight and heat resistance of the polyimide adhesive are lowered and the production cost is increased.

  Preferred examples of the diamine having a siloxane structure used in the present invention include bis (γ-aminopropyl) tetramethyldisiloxane (GAPD, n = 1), bis (γ-aminopropyl) polydimethyldisiloxane (PSX). -4, n = 4), bis (γ-aminopropyl) polydimethyldisiloxane (PSX-8, n = 8), etc., and the diamine containing a siloxane structure is used in one or a mixture of two or more. be able to.

  In the formula, A1 is a trivalent functional group, A2 is a tetravalent functional group, n1 is an integer of 0 or 1-3, n2 is an integer of 0 or 1-4, X is an acid, and q is the number of bases of the acid. Each is shown.

  More specifically, as an example of A1, it is preferable to select and use from the compound of the following chemical formula 4a.

  As an example of A2, it is preferable to select and use from the compound of the following chemical formula 5a.

In the formula, R represents —O—, —CH ₂ —, —CO—, or —SO ₂ —, and n ₃ represents 0 or 1.

  Any one or two or more mixed forms of polyamino compounds selected from the group consisting of the triamine represented by Chemical Formula 4 and the tetraamine represented by Chemical Formula 5 form a three-dimensional network structure of polyimide to form a linear structure. Compared to the structure of polyimide, it increases the free volume of molecular units between main chains and increases fluidity during high-temperature processes, and at the same time, improves heat resistance and improves high-temperature processability and reliability. To do. At this time, the preferred amount of the polyamino compound used is 0.01 to 5 moles with respect to 100 moles of the tetracarboxylic dianhydride represented by the chemical formula 1, and if it is less than 0.01 moles, a three-dimensional network is used. It is difficult to expect properties, and when the amount exceeds 5 moles, problems due to gelation are likely to occur during polymerization, and on the contrary, the high-temperature flow properties and adhesive strength of the adhesive decrease due to gelation.

  Examples of specific compounds of polyfunctional polyamino used in the present invention include 3,3 ′, 4,4′-tetraaminodiphenyl ether, 3,3 ′, 4,4′-tetraaminodiphenylmethane, 3,3 ', 4,4'-tetraaminobenzophenone, 3,3', 4,4'-tetraaminodiphenyl sulfone, 3,3 ', 4,4'-tetraaminobiphenyl, 1,2,4,5-tetraamino Benzene, 3,3 ′, 4-triaminodiphenyl, 3,3 ′, 4-triaminodiphenylmethane, 3,3 ′, 4-triaminobenzophenone, 3,3 ′, 4-triaminodiphenylsulfone, 3,3 A compound comprising ', 4-triaminodibiphenyl and 1,2,4-triaminobenzene, or 3,3 which is a mono-, di-, tri- or tetra-acid salt of said compound , 4,4′-tetraaminodiphenyl ether tetrahydrochloride, 3,3 ′, 4,4′-tetraaminodiphenylmethane tetrahydrochloride, 3,3 ′, 4,4′-tetraaminobenzophenone tetrahydrochloride, 3,3 ′, 4 , 4′-tetraaminodiphenylsulfone tetrahydrochloride, 3,3 ′, 4,4′-tetraaminobiphenyltetrahydrochloride, 1,2,4,5-tetraaminobenzenetetrahydrochloride, 3,3 ′, 4-triamino Diphenyltrihydrochloride, 3,3 ′, 4-triaminodiphenylmethane trihydrochloride, 3,3 ′, 4-triaminobenzophenone trihydrochloride, 3,3 ′, 4-triaminodiphenylsulfone trihydrochloride, 3, 3 ', 4-to It is preferable to use any one or a mixture of two or more selected from the group consisting of raminodibiphenyl trihydrochloride and 1,2,4-triaminobenzene dihydrochloride. More preferably, among the polyfunctional polyamino compounds, compounds not in the form of salt additives are used. In this case, the rate at which gelation is formed during the reaction is shortened. Therefore, when a three-dimensional network structure is formed, the ratio is adjusted by using a salt additive type compound in combination according to the gelation rate adjustment. be able to.

  The 3,4-diaminobenzoic acid represented by the chemical formula 6 plays a role of increasing the adhesive strength and heat resistance with a metal. At this time, the preferred amount of 3,4-diaminobenzoic acid used is 0.03 to 10 mol with respect to 100 mol of tetracarboxylic dianhydride. It is difficult to expect the effect of increasing the force, and if it exceeds 10 moles, the adhesive property with the polymer base material will be deteriorated on the contrary, the flow property of the adhesive at high temperature is lowered and the adhesive property of the adhesive is lowered. .

  The polyimide adhesive composition of the present invention comprises (A) an acid component of an aromatic tetracarboxylic dianhydride, (B) a diamine, (C) a diamine containing a siloxane structure, (D) a polyamino compound, and (E). It is classified into an amine component containing 3,4-diaminobenzoic acid.

  At this time, when an excessive amount of the amine component is used as compared with the acid component of tetracarboxylic dianhydride, the adhesive strength with the metal is lowered and the adhesive strength with the polymer is improved.

  Therefore, the composition for polyimide adhesives of the present invention comprises (B) diamine 60 to 98 mol, (C) diamine containing a siloxane structure 0.05 to 100 mol per 100 mol of (A) aromatic tetracarboxylic dianhydride. 40 mol, (D) 0.01-5 mol of a polyamino compound, and (E) 3,4-diaminobenzoic acid 0.03-10 mol are used. More preferably, the suitable content of the total amine component is used in an amount of 101 to 106 moles per 100 moles of the (A) aromatic tetracarboxylic dianhydride.

  At this time, when a polyimide is produced by polymerizing (A) aromatic tetracarboxylic dianhydride and (B) diamine, preferred solvents are N-methyl-2-pyrrolidone (NMP), N, N-dimethyl. Aprotic polar solvents such as formamide (DMF), N, N-dimethylacetamide (DMAc), dimethylsulfoxide (DMSO), sulfolane, hexamethylphosphoric triamide, 1,3-dimethyl-2-imidazolidone, phenol, cresol Phenolic solvents such as xylphenol and p-chlorophenol. If necessary, ether solvents such as diethylene glycol and dimethyl ether, and aromatic solvents such as benzene, toluene, and kuxylene can be used. In addition, methyl ethyl ketone, acetone, tetrahydrofuran, dioxane, monoglyme, methyl cellosolve, cellosolve acetate, methanol , Ethanol, isopropanol, methylene chloride, chloroform, trichloroethylene, nitrobenzene and a tertiary amine such as pyridine can be used in combination. Any one or two or more of the proposed solvents may be used in combination.

  In the present invention, the polyimide adhesive composition is charged in an organic solvent and vigorously stirred under a nitrogen atmosphere to react at 100 ° C. or lower for 1 to 10 hours to produce a polyamic acid that is a polyimide precursor, Provided is a method for producing a polyimide obtained by applying or coating the polyamic acid and then performing a thermal imidization reaction at 250 to 500 ° C.

1. Step of polymerizing polyamic acid which is a precursor of polyimide At least one of tetracarboxylic dianhydrides represented by Chemical Formula 1 in the temperature range of −10 ° C. to 100 ° C. according to the proper molecular weight and relative viscosity of the polyamic acid. At least one kind of diamine represented by the chemical formula 2, at least one kind of diamine having a siloxane structure represented by the chemical formula 3, and a polyamino compound of tri- or tetraamine represented by the chemical formula 4 or the chemical formula 5. An appropriate amount of at least one or more 3,4-diaminobenzoic acid represented by the above chemical formula 6 is added, and the mixture is vigorously stirred under a nitrogen atmosphere with a solvent to react at 100 ° C. or lower to produce a polyamic acid. At this time, the preferred reaction time is 1 to 10 hours, more preferably 2 to 5 hours. If the reaction time is less than 1 hour, the molecular weight distribution of the polyimide is so wide that the properties of the adhesive are not uniform, and if the reaction time is more than 10 hours, the productivity is lowered.

2. Polyimide manufacturing step using thermal imidization step After applying or coating the polyamic acid, which is a polyimide precursor, to a substrate, it can be imidized by applying heat up to a maximum of 250 to 500 ° C, and a drying step In order to promote imidization, polyamic acid dissolved in a solvent is added to tertiary amines such as pyridine, triethylamine, tributylamine, and isoquinoline, acid anhydrides such as acetic anhydride, propionic anhydride, and benzoic anhydride, Add dehydrating ring closure agent, ring closure catalyst, etc.

  If the polyimide is soluble in the solvent, suitable chemical imidization methods that can be used are: first, tetracarboxylic dianhydride and diamine, optionally tributylamine, triethylamine, triphenyl phosphite, isoquinoline, 100 ° C. or higher, preferably in the presence of a catalyst of 25 parts by weight or less of the total reactant in an organic solvent such as pyridine or in the presence of a dehydration catalyst such as p-toluenesulfonic acid of 25 parts by weight or less of the total reactant. The polyimide can be obtained directly by heating to 180 ° C. or higher. In addition, after reacting tetracarboxylic dianhydride and diamine in an organic solvent at 100 ° C. or lower to obtain polyamic acid which is a precursor of polyimide, acid such as acetic anhydride, propionic anhydride, benzoic anhydride, etc. There are methods such as adding a ring closure catalyst such as anhydride, carbodiimide compounds such as dicyclohexylcarbodiimide and ring closure catalysts such as pyridine, isoquinoline, imidazole, triethylamine as necessary, and ring closure at a relatively low temperature (room temperature to 100 ° C.). . At this time, the dehydrating ring-closing agent and the ring-closing catalyst are used in a molar ratio of 2 to 10 with respect to tetracarboxylic dianhydride.

  The polyimide polymerized by the above production method preferably has a weight average molecular weight of 10,000 to 200,000, more preferably 30,000 to 100,000, in order to satisfy mechanical strength, heat resistance and adhesive properties at the same time. Have. At this time, if the weight average molecular weight of the polyamic acid is less than 10,000, the molecular weight is too small, and there is a possibility that a large amount of adhesive flows during the high-temperature bonding process, causing problems such as contamination at the bonding site. When applied to the adhesive tape, a powdery burr (a jagged cross section) is generated in the punching adhesion process. Also, if the weight average molecular weight of the polyamic acid exceeds 200,000, the molecular weight distribution is relatively wide and the adhesive properties are non-uniform. Especially when the adhesive is coated on a base film or the like, The interfacial adhesion between the adhesive layers is uneven, and the interfacial adhesion is reduced.

  The polyimide obtained by the present invention is excellent in electrical insulation and thermal resistance, and has excellent characteristics when applied to uses of tapes for electronic parts that can be hot-melt bonded under high temperature taping conditions.

  The present invention also relates to a heat-resistant substrate film and a polyimide adhesive prepared by dissolving the polyimide prepared above in an organic solvent so that the solid content is 15 to 25% by weight. Provided is a polyimide adhesive tape comprising a polyimide adhesive layer formed by applying and drying on one side or both sides of a material film.

  The base film used in the present invention is a heat-resistant film, and heat-resistant resin films such as polyimide, polyphenylene sulfide, polyether, polyparabanic acid, polyethylene terephthalate, and fluorine resin, epoxy resin-glass cloth, Any heat-resistant engineering plastic film such as a composite heat-resistant film such as epoxy resin-polyimide-glass cloth can be used without particular limitation, but most preferably a polyimide film is used.

  Commercial polyimide films include Regulus (Mitsui Toatsu Chemicals, Inc.), Kapton (Du Pont Co.), Upilex (Ube Industries, Ltd.), Apical AH, NPI, HP (Kanegafuchi Chemical Industry Co., Ltd.). The preferred thickness is 5 to 150 μm, and the thickness of the polyimide adhesive layer is more preferably 5 to 50 μm. In particular, in the case of an adhesive tape for LOC applications, a 25 μm or 50 μm polyimide film is used as the substrate film.

  Moreover, in order to improve the adhesive force between a base film and a polyimide adhesive layer, it is also preferable to surface-treat a base film. The surface treatment method is not particularly limited, and a normal method can be adopted, but a plasma, corona or silane treatment method is preferably used. In addition, for the purpose of producing an adhesive sheet composed only of a polyimide adhesive layer, a release film that has been subjected to a release treatment with a silicon-based release agent may be used on the surface of the base film, and in this case, a preferable thickness is used. The thickness is 1 to 200 μm.

  In the above, the organic solvent comprises N-methyl-2-pyrrolidone, N, N-dimethylformamide, N, N-dimethylacetamide, dimethyl sulfoxide, sulfolane, hexamethylphosphoric triamide, and 1,3-dimethyl-2-imidazolidone. Any one selected from a non-furotonic polar solvent or a phenolic solvent consisting of phenol, cresol, xylphenol and p-chlorophenol is used.

  Next, the present invention will be described in more detail with reference to examples.

  The following examples are for explaining the present invention more specifically, and do not limit the scope of the present invention.

<Example 1>
First, 200 g of (B) diamine, (C) diamine containing a siloxane structure, (D) polyamino compound and (E) 3,4-diaminobenzoic acid in a reactor equipped with a stirrer, reflux condenser and nitrogen inlet. N-methyl-2-pyrrolidone (NMP) was added and dissolved at 15 ° C., and then (A) tetracarboxylic anhydride was added, and the mixture was vigorously stirred in a nitrogen atmosphere for 5 hours to synthesize polyamic acid. At this time, the total amount of all monomers was 15% by weight of the total reaction product including the solvent.

Add 50 mL of toluene and 3.0 g of p-toluenesulfonic acid to the resulting polyamic acid, heat at 190 ° C., and create an azeotropy environment with toluene as the reaction progresses, making moisture easy While being separated, an imidization reaction was performed for 6 hours. Thereafter, the polyimide polymerization solution was poured into methanol, and the resulting precipitate was separated, pulverized, washed and dried, thereby obtaining a powdered polyimide. When the produced polyimide was subjected to FT-IR measurement, a peak indicating conversion of amic acid to an imide group could be confirmed in a region around 1776 cm ⁻¹ .

  In the process of further dissolving the polyimide in the powder state in N-methyl-2-pyrrolidone (NMP), a polyimide adhesive solution was prepared so that the solid content would be 20% by weight. Then, after each said polyimide adhesive liquid was apply | coated on the glass plate with the knife coater, it was made to dry at 80 degreeC with a vacuum dryer for 30 minutes, the solvent was removed, and after peeling a film from the glass plate after that, it was further 150 degreeC For 5 minutes and at 250 ° C. for 5 minutes to produce a polyimide film having a thickness of 50 μm.

  In addition, the polyimide adhesive solution produced above was applied on a polyimide film (trade name: Apical AH, Kanegafuchi Chemical Industry Co., Ltd.) having a thickness of 50 μm instead of the glass plate, and then at 100 ° C. 5 minutes at 130 ° C., 5 minutes at 150 ° C., 5 minutes at 200 ° C., and 5 minutes at 200 ° C. to remove the solvent, and then finally dried at 250 ° C. for 5 minutes to obtain a polyimide adhesive tape having a thickness of 20 μm. Manufactured.

  Hereinafter, the polyimides of Examples 2 to 18 and Comparative Examples 1 to 10 were synthesized according to Tables 1 and 2.

  In Table 1 below, (A ′) is a tetracarboxylic dianhydride having a structure of X3 which is a structure other than X1 and X2, (C) is a diamine having a siloxane structure, and (F) is a tetracarboxylic acid. The mole ratio of total amine compound to 100 moles of dianhydride is shown. In this case, the total amine compound includes (B) diamine, (C) diamine having a siloxane structure, (D) polyamino compound, and (E) 3,4-diaminobenzoic acid.

<Experimental example 1>
The physical properties of the polyimide adhesive tapes produced in Examples 1-18 and Comparative Examples 1-10 were measured as follows.

1. Relative Viscosity Table 3 shows the relative viscosities η _inh (polyimide diluted in N, N-dimethylacetamide at 0.05% by weight) of the polyimides produced in Examples 1-18 and Comparative Examples 1-10.

2. Weight average molecular weight The weight average molecular weights of the polyimides produced in Examples 1 to 18 and Comparative Examples 1 to 10 were measured using GPC (Gel Permeation Chromatography) and shown in Table 3.

  Measurement conditions were as follows.

  Apparatus: YOUNGLIN Autocho-GPC, detector: UV730D, solvent transfer pump: SP930D, column oven: CTS30, column temperature: 25 ° C., eluent: N, N-dimethylacetamide, eluent flow rate: 1.0 mL / min, Sample concentration: 0.2% by weight, standard sample: polystyrene.

3. Glass transition temperature The glass transition temperature was measured using DSC (Differential Scanning Calorimetry) with respect to the polyimide adhesive tape manufactured in Examples 1-18 and Comparative Examples 1-10. At this time, the rate of temperature increase was measured at a temperature range of 10 ° C./min and 50 to 300 ° C. and is shown in Table 3 below.

4.5% Pyrolysis Temperature The polyimide adhesive tapes produced in Examples 1-18 and Comparative Examples 1-10 were measured for 5% pyrolysis temperature using TGA (Thermogravimetry Analysis). At this time, the rate of temperature increase was measured at a temperature range of 10 ° C./min and 50 to 900 ° C. and is shown in Table 3 below. The 5% pyrolysis temperature originally indicates the temperature at which the weight is relatively decreased by 5% with respect to the mass as 100%.

5. Elastic Modulus Elastic modulus was measured for the polyimide adhesive tapes produced in Examples 1-18 and Comparative Examples 1-10 using DMTA (Dynamic Mechanical Thermal Analysis). At this time, the elastic modulus values at 25 ° C. and 190 ° C. were measured in a temperature range of 50 to 250 ° C. under the conditions of 1 Hz and a temperature increase rate of 5 ° C./min.

6). Adhesive strength The polyimide adhesive tapes produced in Examples 1 to 18 and Comparative Examples 1 to 10 were subjected to nickel iron plywood or PIX-3000 solution (Hitachi Chemical) at 300 ° C. and 350 ° C. under a pressure of 5 kg / cm ² , respectively. After bonding on the coated plate, the T-Peel test was performed at a speed of 50 mm / min at room temperature to evaluate the adhesive force. The results are shown in Table 3 below.

7). Thermal cycle test The polyimide adhesives prepared in Examples 1 to 18 and Comparative Examples 1 to 10 were coated on both sides of a polyimide film having a thickness of 50 μm, and the adhesive layers were laminated to a thickness of 25 μm. An adhesive tape having a different structure was produced.

Thereafter, the thickness of 200μm the one side of the adhesive tape, was heat pressed under a pressure of 5Kg / cm ² at 300 ° C. and 350 ° C. in a copper plate of size 2.5 cm × 2.5 cm. Next, the other surface of the double-sided adhesive tape is thermocompression bonded to a glass chip coated with a 2.5 cm × 2.5 cm PIX-3000 solution (Hitachi Chemical) at 300 ° C. under a pressure of 5 kg / cm ^2. A test sample was prepared.

  A thermal cycle test of −65 ° C. to 150 ° C. was performed using the evaluation sample. At this time, the thermal cycle test was performed under the conditions of 1000 cycles, with each cycle of 30 minutes at 150 ° C. and −65 ° C. as one cycle. After the thermal cycle test, the presence or absence of peeling and foaming was observed, and the results are shown in Table 3 below.

  That is, for the polyimide adhesive tapes produced in each of the examples and comparative examples, 10 evaluation samples were produced, and the number of evaluation samples without peeling and foaming is shown in Table 3.

  The weight average molecular weights of the polyimides produced in Examples 1 to 18 and Comparative Examples 1 to 10 showed values in the range of 45000 to 153000. In Comparative Examples 7 and 8, the weight average molecular weights were 210,000, respectively. And 220,000, showing values over 200000.

In the case of the polyimide adhesive tape manufactured in Examples 1 to 18, the elastic modulus value at 190 ° C. was a value in the range of 2.9 × 10 ^{8 to} 9.7 × 10 ⁸ dyne / cm ² . for polyimide adhesive tape produced in Comparative examples 5 and 6, the elastic modulus value of 1.9 × 10 ^8, respectively, were relatively low and ^{7.1 × 10 7 dyne / cm 2} . Therefore, due to the low elastic modulus value at high temperature, the polyimide adhesive tapes manufactured in Comparative Examples 5 and 6 all have good adhesive strength with copper foil, nickel iron alloy and PIX-3000 at 300 ° C. and 350 ° C. As shown, in the thermal cycle test, 6 out of 10 pieces and 4 pieces were peeled off.

  In the case of the polyimide adhesive tape manufactured in Examples 1 to 18, the adhesive strengths with copper foil, nickel iron alloy and PIX-3000 all showed good values of 1 kgf / cm or more at 300 ° C and 350 ° C. The polyimide adhesive tapes manufactured in Comparative Examples 1 and 2 have a low adhesive strength with PIX-3000 of less than 1 kgf / cm, and the polyimide adhesive tapes manufactured in Comparative Examples 3 and 4 are copper foil, nickel. The adhesive strength with the iron alloy showed a low value of less than 1 kgf / cm. Moreover, the adhesive force with the polyimide adhesive tape manufactured by Comparative Examples 7-10 was less than 1 Kgf / cm, and the adhesive characteristic fell, all with copper foil, nickel iron alloy, and PIX-3000.

  In addition, in the case of the polyimide adhesive tape manufactured using the adhesive composition of the present invention, peeling and foaming are not generated, but the polyimide adhesive tape manufactured using the comparative adhesive composition is peeled off. And foaming was induced.

As mentioned above, although only the specific example of this invention was demonstrated in detail, it cannot be overemphasized that this invention is not limited to the example which concerns. It will be apparent to those skilled in the art that various changes and modifications can be made within the scope of the claims, and these are naturally within the technical scope of the present invention. Understood.

Claims (7)

(A) a tetracarboxylic dianhydride represented by the following chemical formula 1,
(B) a diamine represented by the following chemical formula 2,
(C) a diamine containing a siloxane structure represented by the following chemical formula 3,
(D) any one or two or more mixed forms of polyamino compounds selected from the group consisting of a triamine represented by the following chemical formula 4 and a tetraamine represented by the following chemical formula 5;
(E) A composition for polyimide adhesive composed of 3,4-diaminobenzoic acid represented by the following chemical formula 6.

(In the formula, X represents a divalent functional group.)

(In the formula, Y represents a divalent functional group.)

(In the formula, R ₄ represents an alkyl group having 1 to 20 carbon atoms, and n ′ represents an integer of 1 to 20).

(In the formula, A1 is a trivalent functional group, A2 is a tetravalent functional group, n1 is an integer of 0 or 1-3, n2 is an integer of 0 or 1-4, X is an acid, and q is the number of bases of the acid. Are shown respectively.)

In the tetracarboxylic dianhydride represented by the chemical formula 1, any one selected from the compound represented by the following chemical formula 1b and the compound represented by the following chemical formula 1b, X is selected from the compounds represented by the following chemical formula 1a 2. The composition for polyimide adhesive according to claim 1, comprising two compounds (X2), wherein the molar fraction of X1 and X2 is 1: 0 to 0.5: 0.5.

  The polyimide adhesive composition comprises (A) 100 mol of tetracarboxylic dianhydride, (B) 60 to 98 mol of diamine, (C) 0.05 to 40 mol of diamine containing a siloxane structure, (D) The composition for polyimide adhesive according to claim 1, comprising 0.01 to 5 mol of a polyamino compound and 0.03 to 10 mol of (E) 3,4-diaminobenzoic acid.   The polyimide adhesive composition comprises (B) a diamine, (C) a diamine containing a siloxane structure, (D) a polyamino compound, and (E) with respect to (A) 100 moles of the acid component of tetracarboxylic dianhydride. 2. The composition for polyimide adhesive according to claim 1, wherein the total amine component containing 3,4-diaminobenzoic acid is 101 to 106 mol.   The composition for polyimide adhesive according to claim 1 is charged in an organic solvent, stirred in a nitrogen atmosphere, and reacted at 100 ° C. or lower for 1 to 10 hours to produce a polyamic acid which is a polyimide precursor, and the polyamide A method for producing a polyimide, characterized in that after applying or coating an acid on a substrate, a thermal imidization reaction is performed at a temperature of 250 to 500 ° C.   The method for producing a polyimide according to claim 5, wherein the produced polyimide has a weight average molecular weight of 10,000 to 200,000. A heat-resistant substrate film;
The polyimide prepared in claim 5 is dissolved in an organic solvent, and a polyimide adhesive prepared to have a solid content of 15 to 25% by weight is applied to one or both sides of the base film and dried. A polyimide adhesive tape for electronic parts, comprising a polyimide adhesive layer having a thickness of 5 to 150 μm formed.