CN1637034B - Polyurethane-imide resin, adhesive composition, and adhesive composition for circuit connection - Google Patents

Abstract

The invention provides a polyurethane-imide resin, an adhesive composition and an adhesive composition for circuit connection. The polyurethane-imide resin of the present invention is represented by the following general formula ,

in the formula , R¹Is a divalent organic radical containing an aromatic or aliphatic ring, R²Is a divalent organic group having a molecular weight of 100 to 10000, R³Is a tetravalent organic group having 4 or more carbon atoms, and n and m are integers of 1 to 100.

Description

Polyurethane-imide resin, adhesive composition, and adhesive composition for circuit connection

technical field

The present invention relates to a polyurethane-imide resin, an adhesive composition using the polyurethane-imide resin, and an adhesive composition for circuit connection using the adhesive composition.

Background technique

Organic materials such as epoxy resins are often used in the semiconductor field. In the field of packaging materials, 90% or more of packaging systems are being replaced with resin packaging systems. The packaging material is a composite material composed of epoxy resin, curing agent, various additives, inorganic fillers, etc., and cresol novolac epoxy resin is often used as the epoxy resin. However, the cresol novolac type epoxy resin does not have the required characteristics in terms of satisfying characteristics such as low water absorption and low modulus of elasticity, so it is difficult to cope with the surface mount method. For this reason, many novel and high-performance epoxy resins that replace cresol novolac epoxy resins have been proposed and have been put into practical use.

In addition, as an organic material such as epoxy resin, as a conductive adhesive for die bonding, a silver paste obtained by mixing silver powder with epoxy resin is often used. However, as the method of mounting semiconductor devices on wiring boards has shifted to the surface mount method, there has been an increasing demand for silver pastes to improve solder reflow resistance. In order to solve this problem, improvement of porosity, peel strength, water absorption rate, elastic modulus, etc. of the adhesive layer for die-bonding after hardening is progressing.

In the field of semiconductor packaging, flip-chip packaging, in which IC chips are directly mounted on printed wiring boards or flexible wiring boards, is attracting attention as a new packaging method that adapts to lower costs and higher precision. As the flip-chip packaging method, a method of providing solder bumps on the terminals of the chip to perform solder connection or a method of electrically connecting with a conductive adhesive is known. In these methods, there is a problem that a decrease in connection reliability occurs at the connection interface when exposed to various environments due to the stress due to the difference in thermal expansion coefficient between the chip and the substrate to be connected. Therefore, for the purpose of relieving the stress at the connection interface, generally, a method of injecting an epoxy resin-based underfill material into the chip/substrate gap is being studied. However, the under-fill implantation step complicates the process, which is disadvantageous in terms of productivity and cost. In order to solve such a problem, recently, flip-chip packaging using an anisotropic conductive adhesive having anisotropic conductivity and sealing performance is attracting attention from the viewpoint of process simplicity.

On the other hand, in recent years, in the fields of semiconductors, liquid crystal displays, and the like, various adhesive materials have been used for fixing electronic components or for circuit connection. In these applications, higher densification and finer details are increasing, and higher adhesion and reliability are required for adhesives.

In particular, as a circuit connection material, in the connection between a liquid crystal display and a TCP or an FPC (flexible printed circuit) and a TCP, or between an FPC and a printed circuit board, an anisotropic conductive material in which conductive particles are dispersed in an adhesive is used. adhesive. In addition, recently, even when semiconductor silicon chips are packaged on substrates, instead of conventional wire bonding, the so-called flip-chip packaging, in which semiconductor silicon chips are directly packaged face-down on the substrate, has begun to be used in this case. Anisotropic conductive adhesive. In addition, in the field of precision electronic equipment, the density of circuits is advancing, and the electrode width and electrode interval are becoming extremely narrow.

A polyurethane-imide resin similar to the present invention is used as a thin-layer composite film in JP-A-05-023558.

Contents of the invention

However, the resin encapsulation system, the conductive adhesive for die bonding, and the flip-chip encapsulation described above have a problem in that the adhesive force with the adherend deteriorates across the board. In addition, as mentioned above, in the field of precision electronic equipment, the density of circuits is increasing, and the electrode width and electrode spacing are becoming extremely narrow. Therefore, the connection conditions for using conventional epoxy resin-based circuit connection adhesives, There are problems such as wiring falling off, peeling, and misalignment. In addition, in order to improve productivity, shortening of the connection time of 10 seconds or less is strongly demanded, and low-temperature rapid curing becomes essential.

The present invention provides a urethane-imide resin suitable for an adhesive for circuit connection or semiconductor encapsulation with excellent adhesive force, and an adhesive composition using the urethane-imide resin. Moreover, this invention provides the said adhesive composition which has the adhesive force which can perform excellent low-temperature connection and can shorten connection time, and the adhesive composition for circuit connections using this composition. Furthermore, these adhesive compositions are also excellent in connection reliability.

The invention described in claim 1 provides a polyurethane-imide resin excellent in adhesiveness.

The invention described in claim 2 provides an easily available polyurethane-imide resin in addition to the invention described in claim 1 .

The invention described in claim 3 provides a polyurethane-imide resin excellent in solubility in addition to the invention described in claim 1 .

The invention described in claim 4 provides a polyurethane-imide resin excellent in solubility in addition to the invention described in claim 1 .

The invention described in claim 5 provides, in addition to the invention described in claim 1 , a polyurethane-imide resin that has excellent solubility and is easy to mold.

The inventions described in claims 6 to 9 provide a polyurethane-imide resin capable of improving adhesion reliability.

The inventions recited in claims 10 and 11 provide an adhesive composition that can be bonded even at a low temperature for a short period of time and is excellent in adhesiveness.

The invention described in claim 12 provides an adhesive composition imparting anisotropic conductivity.

The invention described in claim 13 provides an adhesive composition for circuit connection excellent in connection reliability.

The invention described in claim 1 is a polyurethane-imide resin represented by the general formula (I).

[In the formula (I), ^R1 is a divalent organic group containing an aromatic ring or an aliphatic ring, ^R2 is a divalent organic group with a molecular weight of 100 to 10000, and ^R3 is a tetravalent organic group containing more than or equal to 4 carbons. Valence organic group, n and m are integers from 1 to 100. ]

The invention described in claim 2 is the polyurethane-imide resin described in claim 1, which is obtained by chain-extending a polyurethane oligomer obtained from diisocyanate and diol with tetracarboxylic dianhydride. block copolymers.

The invention according to claim 3 is the polyurethane-imide resin according to claim 1, wherein 10 mol% to 100 mol% of R ¹ in the general formula (I) has a structure represented by the general formula (II).

The invention described in claim 4 is the polyurethane-imide resin described in claim 1, characterized in that, in the general formula (I), 10 mol% to 100 mol% of R ² is represented by the repeated formula (III) A divalent organic group having an average molecular weight of 100 to 10,000 in unit composition.

-(CH ₂ -CH ₂ -CH ₂ -CH ₂ -O)- (III)

The invention described in claim 5 is the polyurethane-imide resin described in claim 1, which has an average molecular weight of 5,000 to 500,000 and is soluble in a ketone-based solvent.

The invention according to claim 6 is an adhesive composition comprising a polyurethane-imide resin and a three-dimensional crosslinkable resin.

The invention described in claim 7 is an adhesive composition containing the polyurethane-imide resin described in claim 1 .

The invention described in claim 8 is the adhesive composition described in claim 7 , which further contains a three-dimensional crosslinkable resin.

The invention according to claim 9 is the adhesive composition according to any one of claims 6 to 8, wherein the polyurethane-imide resin is obtained by chain-extending a polyurethane oligomer with tetracarboxylic dianhydride. block copolymers.

The invention described in claim 10 is the pressure-sensitive adhesive composition described in any one of claims 6 to 8, wherein the three-dimensional crosslinkable resin is at least a radical polymer, and contains a curing agent that generates free radicals by light irradiation or heating. agent.

The invention according to claim 11 is the adhesive composition according to any one of claims 6 to 8, wherein the three-dimensional crosslinkable resin is at least an epoxy resin and contains a latent curing agent.

The invention described in claim 12 is the adhesive composition described in any one of claims 6 to 11, further comprising conductive particles.

The invention described in claim 13 is an adhesive composition for circuit connection using the adhesive composition described in any one of claims 6 to 12 for a member for circuit connection.

Detailed ways

The polyurethane-imide resin of the present invention is a polyurethane-imide resin represented by the general formula (I). In the general formula (I), ^R1 is a divalent organic group containing an aromatic ring or an aliphatic ring, ^R2 is a divalent organic group with a molecular weight of 100 to 10000, and ^R3 is a divalent organic group containing more than or equal to 4 carbons. Quaternary organic group, n and m are integers from 1 to 100.

The divalent organic group containing an aromatic ring or an aliphatic ring represented by ^R in the general formula (I) is a diisocyanate residue, preferably containing 10mol% to 100mol% according to the general formula (II)

In the structure shown, the remaining diisocyanate groups include

etc. These can be used alone or in combination of two or more.

The ^divalent organic group whose molecular weight is 100～10000 represented by R in the general formula (I) is a dibasic alcohol residue, preferably containing 10mol%～100mol%

-(CH ₂ -CH ₂ -CH ₂ -CH ₂ -O)- (III)

The structure composed of the repeating unit represented by

-(CH ₂ -CH(CH ₃ )-O)-,

-(CH ₂ -CH ₂ -O)-,

-(CH ₂ -CH ₂ -CH ₂ -CH ₂ -O)-,

-(CH ₂ -CH(CH ₃ )-O) _a -(CH ₂ -CH ₂ -O) _b -(a/b=9～1/1～9mol% copolymer),

-[CO-(CH ₂ ) ₄ -CO-O-(CH ₂ ) ₂ -O]-,

-[CO-(CH ₂ ) ₄ -CO-O-(CH ₂ ) ₂ -O-(CH ₂ ) ₂ -O]-,

-[CO-(CH ₂ ) ₄ -CO-O-CH ₂ -CH(CH ₃ )-O]-,

-[CO-(CH ₂ ) ₄ -CO-O-(CH ₂ ) ₄ -O]-,

-[CO-(CH ₂ ) ₄ -CO-O-(CH ₂ ) ₆ -O]-,

-[CO-(CH ₂ ) ₄ -CO-O-CH ₂ -C(CH ₃ ) ₂ -CH ₂ -O]-,

-[CO-(CH ₂ ) ₈ -CO-O-(CH ₂ ) ₆ -O]-,

-[CO-(CH ₂ ) ₅ -O]-,

-[CO-O-(CH ₂ ) ₆ -O]-,

A residue of a repeating unit such as -R ⁴ -(Si(CH ₃ ) ₂ -O)-R ⁴ -(R ⁴ is an organic group having 1 to 10 carbon atoms). These can be used 1 type or in combination of 2 or more types. These average molecular weights are preferably from 100 to 10,000, more preferably from 500 to 5,000.

The ^tetravalent organic group containing greater than or equal to 4 carbons represented by R in the general formula (I) is a tetracarboxylic acid anhydride residue, for example,

wait. These can be used 1 type or in combination of 2 or more types.

It is necessary for n and m in the general formula (I) to be an integer of 1-100, more preferably 1-50.

The polyurethane-imide resin of the present invention is preferably a block copolymer obtained by chain-extending a polyurethane oligomer obtained from diisocyanate and diol with tetracarboxylic dianhydride.

Examples of diisocyanates that are constituents of polyurethane oligomers include diphenylmethane-4,4'-diisocyanate, diphenylmethane-2,4'-diisocyanate, toluene-2,4-diisocyanate, toluene -2,6-diisocyanate, 1,6-hexamethylene diisocyanate, 3-isocyanatomethyl-3,5,5-trimethylcyclohexane isocyanate, 1,1'-methylene Bis(4-isocyanatocyclohexane), 1,3-bis(isocyanatomethyl)benzene, 1,3-bis(isocyanatomethyl)cyclohexane, and the like. These may be used alone or in combination.

As diols, polyalcohols with an average molecular weight of 100 to 10,000 are used, and examples of main chain structures include polypropylene glycol, polyethylene glycol, polypropylene glycol/polyethylene glycol copolymer, and poly(1,4-butylene glycol). , poly(ethylene adipate), poly(diethylene adipate), poly(trimethylene adipate), poly(tetramethylene adipate), poly(hexamethylene adipate) methyl ester), poly(neopentylene adipate), poly(hexamethylene sebacate), poly(ε-caprolactone), poly(hexamethylene carbonate), poly(siloxane) and the like. These may be used alone or in combination.

Examples of the tetracarboxylic dianhydride for chain-extending polyurethane oligomers include pyromellitic dianhydride, 3,3′,4,4′-diphenyltetracarboxylic dianhydride, 2,2 ',3,3'-diphenyltetracarboxylic dianhydride, 4,4'-hydroxydiphthalic anhydride, 2,2-bis(3,4-dicarboxyphenyl)propane dianhydrate, 2,2-bis(2,3-dicarboxyphenyl)propane dihydrate, 1,1-bis(2,3-dicarboxyphenyl)ethane dihydrate, 1,1-bis(3 , 4-dicarboxyphenyl) ethane dihydrate, bis(2,3-dicarboxyphenyl)methane dihydrate, bis(3,4-dicarboxyphenyl)methane dihydrate, bis (3,4-Dicarboxyphenyl)sulfone dianhydrate, 3,4,9,10-perylenetetracarboxylic dianhydride, bis(3,4-dicarboxyphenyl)ether anhydrous, benzene-1 , 2,3,4-tetracarboxylic dianhydride, 3,4,3',4'-benzophenone tetracarboxylic dianhydride, 2,3,2',3'-benzophenone tetracarboxylic acid Dianhydride, 2,3,3',4'-benzophenone tetracarboxylic dianhydride, 1,2,5,6-naphthalene tetracarboxylic dianhydride, 2,3,6,7-naphthalene tetracarboxylic dianhydride Dianhydride, 1,2,4,5-naphthalene tetracarboxylic dianhydride, 1,4,5,8-naphthalene tetracarboxylic dianhydride, 2,6-dichloronaphthalene-1,4,5,8-tetra Carboxylic acid dianhydride, 2,7-dichloronaphthalene-1,4,5,8-tetracarboxylic dianhydride, 2,3,6,7-tetrachloronaphthalene-1,4,5,8-tetracarboxylic acid Dianhydride, phenanthrene-1,8,9,10-tetracarboxylic dianhydride, pyrazine-2,3,5,6-tetracarboxylic dianhydride, thiophene-2,3,4,5-tetracarboxylic di anhydride, 2,3,3',4'-biphenyltetracarboxylic dianhydride, 3,4,3',4'-biphenyltetracarboxylic dianhydride, 2,3,2',3'-biphenyl Tetracarboxylic dianhydride, bis(3,4-dicarboxyphenyl)dimethylsilane dihydrate, bis(3,4-dicarboxyphenyl)tolylsilane dihydrate, bis(3,4 -Dicarboxyphenyl) diphenylsilane dihydrate, 1,4-bis(3,4-dicarboxyphenyldimethylsilyl)benzene dihydrate, 1,3-bis(3, 4-dicarboxyphenyl)-1,1,3,3-tetramethyldicyclohexane dihydrate, terephthalic bis(trimellitic acid monoester anhydride), ethylene tetracarboxylic dianhydride, 1,2 , 3,4-butane tetracarboxylic dianhydride, decahydronaphthalene-1,4,5,8-tetracarboxylic dianhydride, 4,8-dimethyl-1,2,3,5,6,7- Hexahydronaphthalene-1,2,5,6-tetracarboxylic dianhydride, cyclopentane-1,2,3,4-tetracarboxylic dianhydride, pyrrolidine-2,3,4,5-tetracarboxylic acid Dianhydride, 1,2,3,4-cyclobutanetetracarboxylic dianhydride, bis(exo-bicyclo[2,2,1]heptane-2,3-dicarboxylic anhydride)sulfone, bicyclo(2,2 , 2)-oct(7)-ene-2,3,5,6-tetracarboxylic dianhydride, 2,2-bis(3,4-dicarboxyphenyl) hexafluoropropane dianhydrate, 2, 2-bis[4-(3,4-dicarboxyphenoxy)phenyl]hexafluoropropane dihydrate, 4,4'-bis(3,4-dicarboxyphenoxy)diphenylsulfide di Anhydrous, 1,4-bis(2-hydroxyhexafluoroiso Propyl)benzenebis(trimellitic anhydride), 1,3-bis(2-hydroxyhexafluoroisopropyl)benzenebis(trimellitic anhydride), 5-(2,5-dioxotetrahydrofuranyl)-3-methyl-3 - Cyclohexene-1,2-dicarboxylic anhydride, tetrahydrofuran-2,3,4,5-tetracarboxylic dianhydride, etc. These may be used alone or in combination.

The polyurethane-imide resin of the present invention can be synthesized by a common method such as a solution polymerization method. For example, in the case of the solution polymerization method, diisocyanate and diol are dissolved in a solvent capable of dissolving the resulting polyurethane-imide resin such as N-methyl-2-pyrrolidone (NMP), and the °C for 1 hour to 5 hours to synthesize a polyurethane oligomer, then add tetracarboxylic dianhydride and react at 70 °C to 180 °C for 1 hour to 10 hours to obtain a polyurethane-imide resin NMP solution. In addition, depending on the situation, adding a monovalent alcohol, oxime, amine, isocyanate, acid anhydride, etc. to continue the reaction can also modify the terminal of the polyurethane-imide resin. In addition, at the time of synthesis, water, alcohol, tertiary amine, etc. can also be used as a catalyst.

From the obtained polyurethane-imide resin solution, the polyurethane-imide resin may be separated by a reprecipitation method with water or the like according to the purpose.

The composition ratio of the diisocyanate and diol constituting the polyurethane oligomer is preferably 0.1 mol% to 1.0 mol% of the diol component relative to 1.0 part of diisocyanate. The composition ratio of the polyurethane oligomer constituting the polyurethane-imide resin and the tetracarboxylic dianhydride is preferably 0.1 mol% to 2.0 mol% of the tetracarboxylic dianhydride based on 1.0 part of the polyurethane oligomer.

The polyurethane-imide resin of the present invention is for the purpose of imparting toughness to an adhesive, etc., and preferably has an average molecular weight of 5,000 to 500,000 in terms of standard polystyrene as measured by gel permeation chromatography using tetrahydrofuran as a solvent. , more preferably 10,000 to 300,000, most preferably 10,000 to 100,000. When the average molecular weight is less than 5,000, the strength of the resin is low, and if it exceeds 500,000, the solubility of the resin is poor.

The polyurethane-imide resin of the present invention is preferably a polyurethane-imide resin that can be dissolved in a ketone-based solvent. As the ketone-based solvent, acetone, methyl ethyl ketone, 2-pentanone, 3-pentanone, Pentanone, 2-hexanone, methyl isobutyl ketone, 2-heptanone, 4-heptanone, diisobutyl ketone, hexanedione, mesityl oxide, diisopropylidene acetone, isophorone , cyclohexanone, methylcyclohexanone, acetophenone, camphor, etc. Among them, acetone or methyl ethyl ketone is preferred because of its low boiling point and easy removal of solvents.

The polyurethane-imide resin of the present invention described above can be used, for example, as an adhesive for encapsulation of semiconductor devices or for circuit connection in display systems such as semiconductors and liquid crystal displays.

The polyurethane-imide resin of the present invention is excellent in adhesiveness alone, but it is preferably used in combination with a three-dimensional crosslinkable resin and a curing agent for the purpose of improving connection reliability.

The three-dimensional crosslinkable resin used in the present invention includes epoxy resins, cyanate resins, imide resins, radical polymer acrylate-methacrylate-maleimide compounds, and the like. They are used with hardeners. Among them, a composition containing an epoxy resin and its latent curing agent is particularly preferable. In addition, the three-dimensional crosslinkable resin is a radical polymer substance, and it is preferable to be a composition containing a curing agent that generates free radicals by light irradiation or heating. In the case of epoxy resins, known curing agents such as imidazole-based, hydrazine-based, boron trifluoride-amine complexes, sulfonium salts, amines, imides, polyamine salts, and dicyandiamide can be used as curing agents. agents or mixtures thereof. As the epoxy resin, bisphenol-type epoxy resins derived from bisphenol A, bisphenol F, bisphenol S, bisphenol D, etc. are used alone or in combination; Epoxy novolac novolac resins, naphthalene-based epoxy resins with a naphthalene skeleton, glycidylamine-type epoxy resins, glycidyl ether-type epoxy resins, biphenyl alicyclics, etc., which have a molecule greater than or equal to 2 Various epoxy resins with a glycidyl group, other known epoxy resins. Among these epoxy resins, in order to prevent electromigration corrosion or corrosion of metal conductor circuits, it is preferred to use those that reduce impurity ions alkali metal ions, alkaline earth metal ions, halogen ions, especially chloride ions or hydrolyzable chlorine to less than or equal to 300ppm. High purity product.

As a curing agent for epoxy resins, known imidazoles, hydrazines, boron trifluoride-amine complexes, sulfonium salts, amines, imides, polyamine salts, dicyandiamide and other curing agents can be used or For mixtures thereof, latent curing agents are preferred. Microencapsulated curing agents coated with polyurethane-based or polyester-based polymers are preferred because they prolong pot life.

Examples of cyanate resins include bis(4-cyanophenyl)ethane, 2,2-bis(4-cyanophenyl)propane, 2,2-bis(3,5-dimethyl-4- Cyanide) methane, 2,2-bis(4-cyanophenone)-1,1,1,3,3,3-hexafluoropropane, α,α′-bis(4-cyanophenone) Cumene, a cyanate compound of a phenol-added dicyclopentadiene polymer, and the like are used alone or as prepolymers of them in combination. Among them, 2,2-bis(4-cyanophenyl)propane and 2,2-bis(3,5-dimethyl-4-cyanophenyl)methane, etc., due to the special dielectric properties of cured products Excellent, so preferred. As the curing agent for the cyanate resin, metal-based reaction catalysts are used, and metal catalysts such as manganese, iron, cobalt, nickel, copper, and zinc are used. Specifically, they are used as organometallic salt compounds such as 2-ethylhexanoate and naphthenate, and organometallic complexes such as acetylacetonate complexes.

The compounding amount of the metal-based reaction catalyst is preferably from 1 ppm to 3000 ppm, more preferably from 1 ppm to 1000 ppm, most preferably from 2 ppm to 300 ppm, based on the cyanate ester compound. When the compounding amount of the metal-based reaction catalyst is less than 1 ppm, the reactivity and curability tend to be insufficient, and if it exceeds 3000 ppm, the control of the reaction becomes difficult, and the tendency to cure too quickly cannot be restrained.

The radical polymerizable substance (radical polymerizable compound) used in the present invention is a compound having a functional group polymerized by radicals, and there are (meth)acrylate resins, maleimide resins, citraconimide resins, Najimid resins and the like can be used in admixture of two or more types. In addition, the radically polymerizable compound can be used in any state of a monomer or an oligomer, and can also be used as a mixture of monomers and oligomers. Here, (meth)acrylate resin means acrylate resin and methacrylate resin (the same applies hereinafter).

The (meth)acrylate resin is obtained by radically polymerizing (meth)acrylate. Examples of (meth)acrylates include methyl (meth)acrylate, ethyl (meth)acrylate, isopropyl (meth)acrylate, isobutyl (meth)acrylate, ethylene glycol di(meth)acrylate ) acrylate, diethylene glycol di(meth)acrylate, trimethylolpropane tri(meth)acrylate, 1,4-butanediol tetra(meth)acrylate, 2-hydroxy-1, 3-Diacryloyloxypropane, 2,2-bis[4-(acryloyloxymethoxy)phenyl]propane, 2,2-bis[4-(acryloyloxyethoxy)phenyl ] propane, dicyclopentenyl (meth)acrylate tridecenyl (tridecyl) (meth)acrylate, tris(acryloyloxyethyl)isocyanurate, urethane (methyl ) acrylate, oxirane-isocyanurate-modified diacrylate, etc., these can be used alone or in combination of two or more. Moreover, radical polymerization inhibitors, such as hydroquinone and methyl ether hydroquinone, can also be used as needed within the range which does not impair curability.

Furthermore, when a radically polymerizable substance having a phosphate ester structure is used, the adhesive force to inorganic substances such as metals can be improved. The amount of the radically polymerizable substance having a phosphate ester structure is 0.1 to 10 parts by weight, preferably 0.5 to 5 parts by weight. The radically polymerizable substance having a phosphate ester structure is obtained as a reaction product of anhydrous phosphoric acid and 2-hydroxyethyl (meth)acrylate. Specifically, there are mono(2-methacryloyloxyethyl) acidic phosphoric acid ester, di(2-methacryloyloxyethyl) acidic phosphoric acid ester, etc., and may be used individually or in combination.

As the maleimide resin, it is a maleimide resin having at least one maleimide group in the molecule. Examples include phenylmaleimide, 1-methyl-2,4-bismaleimidebenzene, N,N'-m-phenylene bismaleimide, N,N'- p-phenylene bismaleimide, N,N'-4,4-biphenylene bismaleimide, N,N',4,4-(3,3-dimethylbisleimide Phenyl) bismaleimide, N, N', 4,4-(3,3-dimethyldiphenylmethane) bismaleimide, N, N', 4,4-(3 , 3-diethyldiphenylmethane) bismaleimide, N, N'-, 4,4-diphenylmethane bismaleimide, N, N'-, 4,4-di Phenylpropane bismaleimide, N,N'-, 4,4-diphenyl ether bismaleimide, N,N'-, 4,4-diphenylsulfone bismaleimide, 2,2-bis(4-(4-maleimidephenoxy)phenyl)propane, 2,2-bis(3-tert-butyl-3,4-(4-maleimidephenoxy) Oxy)phenyl)propane, 1,1-bis(4-(4-maleimidephenoxy)phenyl)decane, 4,4'-cyclohexylene-bis(1-(4- Maleimidephenoxy)phenoxy)-2-cyclohexylbenzene, 2,2-bis(4-(4-maleimidephenoxy)phenyl)hexafluoropropane, and the like. These may be used individually or in mixture of 2 or more types.

The citraconimide resin is a resin obtained by polymerizing a citraconimide compound having at least one citraconimide group in its molecule. Examples of citraconimide compounds include phenylcitraconimide, 1-methyl-2,4-biscitraconimidebenzene, N,N'-m-phenylene biscitraconyl Imine, N, N'-p-phenylene biscitraconimide, N, N'-, 4,4-bisphenylene biscitraconimide, N, N', 4,4-( 3,3-Dimethylbiphenylene) bis-citraconimide, N, N', 4,4-(3,3-dimethyldiphenylmethane) bis-citraconimide, N, N'-,4,4-(3,3-Diethyldiphenylmethane)biscitraconimide, N,N',4,4-diphenylmethane biscitraconimide, N, N',4,4-diphenylpropane biscitraconimide, N,N',4,4-diphenyl ether biscitraconimide, N,N',4,4-diphenylsulfone bis Citraconimide, 2,2-bis(4-(4-citraconimidephenoxy)phenyl)propane, 2,2-bis(3-tert-butyl-3,4-(4- citraconimidephenoxy)phenyl)propane, 1,1-bis(4-(4-citraconimidephenoxy)phenyl)decane, 4,4′-cyclohexylene-bis (1-(4-citraconimidephenoxy)phenoxy)-2-cyclohexylbenzene, 2,2-bis(4-(4-citraconimidephenoxy)phenyl)hexa Fluoropropane, etc. These may be used individually or in mixture of 2 or more types.

As endomethylenetetrahydrophthalic imide resin, it is endomethylenetetrahydrophthalic acid imide having at least one endomethylenetetrahydrophthalic imide group in the molecule. Resin after polymerization of imine compound. Examples of endomethylenetetrahydrophthalimide compounds include phenylendomethylenetetrahydrophthalimide, 1-methyl-2,4-bisendomethylene Tetrahydrophthalimide benzene, N, N'-m-phenylene bis-endomethylene tetrahydrophthalic imide, N, N'-p-phenylene bis-endomethylene tetrahydrophthalate Hydrogenated phthalimide, N, N', 4,4-biphenylene bis-endomethylene tetrahydrophthalimide, N, N'-, 4,4-(3, 3-Dimethylbiphenylene) bis-bridged methylene tetrahydrophthalimide, N, N', 4,4-(3,3-dimethyldiphenylmethane) double-bridged imide Methyltetrahydrophthalimide, N, N'-, 4,4-(3,3-diethyldiphenylmethane) bis-endomethylenetetrahydrophthalimide, N,N',4,4-diphenylmethane bis-endomethylene tetrahydrophthalic imide, N,N'-,4,4-diphenylpropane bis-endomethylene tetrahydrophthalic imide Phthalimide, N, N', 4,4-diphenyl ether bis-bridged methylene tetrahydrophthalic imide, N, N'-, 4,4-diphenylsulfone double bridged imide Methyltetrahydrophthalimide, 2,2-bis(4-(4-endomethylenetetrahydrophthalimidephenoxy)phenyl)propane, 2,2-bis (3-tert-butyl-3,4-(4-methanotetrahydrophthalimidephenoxy)phenyl)propane, 1,1-bis(4-(4-methano phenyltetrahydrophthalimide (phenoxy) phenyl) decane, 4,4'-cyclohexylene-bis(1-(4-endomethylene tetrahydrophthalimide benzene oxy)phenoxy)-2-cyclohexylbenzene, 2,2-bis(4-(4-methylenetetrahydrophthalimidophenoxy)phenyl)hexafluoropropane, and the like. These may be used individually or in mixture of 2 or more types.

When using the radically polymerizable compound described above, a curing agent (polymerization initiator) that generates radicals by light irradiation or heating is used. The curing agent is not particularly limited as long as it is a compound that generates radicals by heat or light, and there are peroxides, azo compounds, etc., and are suitably selected in consideration of the intended connection temperature, connection time, storage stability, etc. In terms of high reactivity and storage stability, it is preferred to select organic peroxides with a half-life of 10 hours at a temperature higher than or equal to 40°C and a half-life of 1 minute at a temperature lower than or equal to 180°C, especially preferred An organic peroxide whose half-life is 10 hours at a temperature higher than or equal to 50° C. and whose half-life is 1 minute is lower than or equal to 170° C. is selected. When the connection time is set at 10 seconds, in order to obtain a sufficient reaction rate, the compounding amount of the curing agent is preferably 1% by weight to 20% by weight, particularly preferably 2% by weight to 15% by weight. As specific compounds of the organic peroxide used in the present invention, diacyl peroxides, peroxydicarbonates, peroxyesters, peroxyketals, dialkyl peroxides, hydrogen peroxide, Selected from among silyl peroxides and the like. Peroxyesters, dialkyl peroxides, hydrogen peroxide, and silyl peroxides, because the chloride ion or organic acid in the initiator is less than or equal to 5000ppm, the organic acid produced after thermal decomposition is less, which can inhibit the use of Corrosion of connection terminals of circuit components formed of metal or the like is particularly preferred.

Examples of diacyl peroxides include isobutyl peroxide, 2,4-dichlorobenzoyl peroxide, 3,5,5-trimethylhexanoyl peroxide, octanoyl peroxide, peroxide Lauroyl peroxide, stearoyl peroxide, succinyl peroxide, benzoyl toluene peroxide, benzoyl peroxide, etc.

Examples of peroxydicarbonates include di-n-propyl peroxydicarbonate, diisopropyl peroxydicarbonate, bis(4-tert-butylcyclohexyl)peroxydicarbonate, bis(2-ethyl Oxymethoxyperoxy)dicarbonate, bis(2-ethylhexylperoxy)dicarbonate, dimethoxybutyldicarbonate, bis(3-methyl-3-methoxybutylperoxy)dicarbonate Oxygen) dicarbonates, etc.

Examples of peroxyesters include cumenyl peroxyneodecanoate, 1,1,3,3-tetramethylbutylperoxyneodecanoate, 1-cyclohexyl-1-methylethyl Peroxyneodecanoate, tert-hexyl peroxyneodecanoate, tert-butyl peroxypivalate, 1,1,3,3-tetramethylbutylperoxy-2-ethylhexanoate, 2 , 5-Dimethyl-2,5-di(2-ethylhexanoylperoxy)hexane, 1-cyclohexyl-1-methylethylperoxy-2-ethylhexanoate, tert-hexylperoxy Oxy-2-ethylhexanoate, tert-butylperoxy-2-ethylhexanoate, tert-butylperoxyisobutyrate, 1,1-bis(tert-butylperoxy)cyclohexane, tert-hexylperoxyisopropyl monocarbonate, tert-butylperoxy-3,5,5-trimethylhexanoate, tert-butyl perlaurate, 2,5-dimethyl-2,5-di (m-toluoyl peroxy)hexane, tert-butylperoxyisopropyl monocarbonate, tert-butylperoxy-2-ethylhexyl monocarbonate, tert-hexyl perbenzoate, tert-butyl peracetate, etc. .

Examples of peroxyketals include 1,1-bis(tert-hexylperoxy)-3,3,5-trimethylcyclohexane, 1,1-bis(tert-hexylperoxy)cyclohexane, 1,1-bis(tert-butylperoxy)-3,3,5-trimethylcyclohexane, 1,1-(tert-butylperoxy)cyclododecane, 2,2-bis(tert-butyl base peroxy) decane, etc.

Examples of dialkyl peroxides include α,α'-bis(tert-butylperoxy)diisopropylbenzene, dicumenyl peroxide, 2,5-dimethyl-2,5 - Di(tert-butylperoxy)hexane, tert-butylcumyl peroxide and the like.

Examples of hydrogen peroxides include dicumyl hydroperoxide, cumene hydroperoxide, and the like.

Examples of silyl peroxides include tert-butyltrimethylsilyl peroxide, bis(tert-butyl)dimethylsilyl peroxide, tert-butyltrivinylsilyl peroxide, bis(tert-butyl)divinylsilyl peroxide, tri(tert-butyl)vinylsilyl peroxide, tert-butyltriallylsilyl peroxide, bis (tert-butyl)diallylsilyl peroxide, tri(tert-butyl)allylsilyl peroxide, and the like.

In the case where the adherend is, for example, a connecting terminal of a metal circuit part, in order to suppress its corrosion, it is preferred that the chloride ion and organic acid contained in the curing agent be less than or equal to 5000 ppm, and it is more preferred that after thermal decomposition A curing agent that generates less organic acid. In addition, from the viewpoint of improving the stability of the adhered body, it is preferred to have a weight retention rate greater than or equal to 20% by weight after being left open for 24 hours at room temperature (25° C.) and normal pressure. These curing agents can be used in admixture as appropriate.

The curing agents that generate these free radicals can be used alone or in combination, and can also be used in combination with decomposition accelerators, inhibitors, and the like.

In addition, microencapsulated curing agents coated with polyurethane-based or polyester-based high-molecular substances are preferred because they prolong pot life.

The adhesive composition of the present invention may also use polyvinyl butyral resin, polyvinyl formal resin, polyester resin, polyamide resin, poly Polymer components of imide resin, xylene resin, phenoxy resin, polyurethane resin, urea resin, etc., acrylic rubber, etc. These polymer components preferably have a molecular weight of 10,000 to 10,000,000.

The conductive particles used in the present invention are not particularly limited as long as they have electrical conductivity capable of obtaining electrical connection, and include metal particles such as Au, Ag, Ni, Cu, Co, solder, carbon, and the like. In addition, conductive particles obtained by coating non-conductive glass, ceramics, plastic, etc. with the above-mentioned metal conductive substance can also be used. At this time, in order to obtain sufficient electrical conductivity, it is preferred that the thickness of the coated metal layer be greater than or equal to The conductive particles are used in the range of 0.1% by volume to 30% by volume relative to the binder component, preferably in the range of 0.1% by volume to 20% by volume.

In the adhesive composition of the present invention, the proportion of the polyurethane-imide resin (A) and the three-dimensional crosslinking resin (B) constituted by the structure represented by the general formula (I) is expressed by (A) in parts by weight. :(B)=1:99 to 99:1 can be used, preferably 10:90 to 90:10.

In adhesive compositions using urethane-imide resins, fillers or particles can be added for the purpose of improving fluidity and physical properties, or for the purpose of adding electrical conductivity, anisotropic electrical conductivity, and thermal conductivity. . Such fillers or particles may be silicon dioxide, antimony trioxide, gold, silver, copper, nickel, aluminum, stainless steel, carbon, ceramics, or the above-mentioned metals, non-conductive glass, ceramics, plastics, etc. A core is a filler or particle in which the above-mentioned metal or carbon is coated on the core. The amount of fillers or particles used is not particularly limited, but preferably 0.1 to 50% by volume relative to 100% by volume of the adhesive composition containing polyurethane-imide resin.

The adhesive composition containing the polyurethane-imide resin of the present invention may appropriately add various polymers for the purpose of improving the adhesive force and the physical properties of the adhesive. The polymer used is not particularly limited. As such polymers, general-purpose phenoxy resins such as bisphenol A phenoxy resins, bisphenol F phenoxy resins, bisphenol A and bisphenol F copolymer phenoxy resins, and polymethyl phenoxy resins can be used. Acrylic esters, polyacrylates, polyimides, polyurethanes, polyesters, polyvinyl butyral, SBS and its epoxy modified products, SEBS and its modified products, etc. These can be used individually or in mixture of 2 or more types. Furthermore, these polymers may contain siloxane bonds or fluorine substituents. These polymers can be suitably used as an adhesive composition if the mixed resins are completely dissolved in each other, or if they undergo microphase separation and become cloudy. The molecular weight of the above-mentioned polymer is not particularly limited, but generally, the average molecular weight is preferably from 5,000 to 150,000, particularly preferably from 10,000 to 80,000. When the value is less than 5,000, the physical properties of the binder tend to decrease, and when it exceeds 150,000, the compatibility with other components tends to deteriorate. The amount used is preferably 20 parts by weight to 320 parts by weight relative to 100 parts by weight of the polyurethane-imide resin-containing adhesive composition. When the amount used is less than 20 parts by weight or exceeds 320 parts by weight, fluidity and adhesiveness tend to decrease.

To the adhesive composition containing the polyurethane-imide resin of the present invention, a softener, an accelerator, an antiaging agent, a colorant, a flame retardant, and a coupling agent may be added as appropriate.

The adhesive composition containing the polyurethane-imide resin of the present invention can be used in a paste form when it is liquid at normal temperature (25° C.). When it is solid at room temperature, it can also be gelatinized using a solvent in addition to heating. As the solvent that can be used, as long as it has no reactivity with the adhesive composition and additives and shows sufficient solubility, it will not be particularly limited, and the boiling point at normal pressure (atmospheric pressure) is preferably 50° C. to 150° C. ℃ solvent. In addition, when the boiling point is lower than or equal to 50° C., there is a concern of volatilization when left at room temperature, and thus use in an open system is limited. In addition, if the boiling point is higher than or equal to 150° C., it will be difficult to volatilize the solvent, which may adversely affect the reliability after bonding.

The adhesive composition containing the polyurethane-imide resin of the present invention can also be used in the form of a film. If necessary, a solvent or the like is added to the adhesive composition to form a solution, and the solution is coated on a release substrate such as a fluororesin film, a polyethylene terephthalate film, a release paper, etc., or made without Substrates such as woven fabrics are impregnated with the above-mentioned solution, placed on a release substrate, and can be used as a film after removing the solvent and the like. It is more convenient from the viewpoint of operability and the like if it is used in the form of a film.

The adhesive composition containing the polyurethane-imide resin of the present invention can be used as an adhesive for different types of adherends having different thermal expansion coefficients. Specifically, it can be used as silver paste, silver film, circuit connection materials represented by anisotropic conductive adhesives, elastomers for CSP, lining fillers for CSP, LOC tapes, adhesive materials for die bonding, etc. etc. are used as representative semiconductor device adhesives.

It is preferable to use the adhesive composition of the present invention for parts for circuit connection. The circuit connection member is composed of a substrate and electrodes. The substrate is not particularly limited as long as it is a substrate on which electrodes necessary for electrical connection are formed, and there are glass or plastic substrates, printed wiring boards, Ceramic wiring boards, flexible printed wiring boards, semiconductor wafers, etc. can be used in combination as necessary.

The conditions for connection are not particularly limited. The connection temperature is 90° C. to 250° C., and the connection time is 1 second to 10 minutes. It is appropriately selected according to the application, adhesive, and substrate, and post-curing may also be performed if necessary. In addition, although the connection is performed by heat and pressure, energy other than heat, such as light, ultrasonic waves, electromagnetic waves, etc., may be used as needed.

Tackifiers such as fillers, softeners, accelerators, anti-aging agents, colorants, flame retardants, coupling agents, terpene-based resins, etc. may be added suitably to the adhesive composition for circuit connection of the present invention. .

Example

Hereinafter, the present invention will be specifically described based on examples, but the present invention is not limited by these examples.

Example 1

In 1-methyl-2-pyrrolidone, diphenylmethane-4,4'-diisocyanate (1.0mol), diphenylmethane-2,4'-diisocyanate ( 1.0mol) and polytetramethylene glycol (0.8mol) with an average molecular weight of 1000 were reacted for 1 hour, and 4,4'-hydroxyphthalic anhydride (1.0mol), triethylamine and 1-methyl-2 - pyrrolidone, further stirring at 100° C. for 3 hours. Further, benzyl alcohol was added, and the mixture was stirred at 100°C for 1 hour to complete the reaction. The obtained solution was put into vigorously stirred water, the precipitate was filtered, and dried in vacuum at 80° C. for 8 hours to obtain polyurethane-imide resin PUI-1. As a result of measuring the obtained polyurethane-imide resin by GPC (gel permeation chromatography), Mw=51000 and Mn=22000 in terms of polystyrene. In addition, this urethane-imide resin was soluble in methyl ethyl ketone at a solid content of 40% by weight.

The obtained polyurethane-imide resin was dissolved in methyl ethyl ketone with a solid content concentration of 40% by weight, and the urethane acrylate (U-108, Shin Nakamura Chemical Co., Ltd. Industry Co., Ltd. product name), 1,1-bis(tert-hexylperoxy)-3,3,5-trimethylcyclohexane (Parhekisa TMH, product name of NOF Corporation) as a curing agent , and then mix and disperse 1.5% by volume of conductive particles. The conductive particles are formed by setting a nickel layer with a thickness of 0.2 μm on the surface of the particle with polystyrene as the core, and setting a metal layer with a thickness of 0.2 μm on the outside of the nickel layer. Conductive particles with a particle size of 5 μm and a specific gravity of 2.5. It was coated on a fluororesin film with a thickness of 80 μm using a coating device, and dried with hot air at 70° C. for 10 minutes to obtain a film-like adhesive with an adhesive layer thickness of 20 μm.

Example 2

The diol component of PUI-1 was changed to poly(hexamethylene carbonate) having an average molecular weight of 2000, and synthesized in the same manner as in Example 1 to obtain PUI-2. As a result of measurement by GPC, Mw=55000 and Mn=25000 in terms of polystyrene.

This PUI-2 was formulated in accordance with Table 1 in the same manner as in Example 1 to obtain a film-like adhesive having a thickness of the adhesive layer of 20 μm.

Example 3

The glycol component of PUI-1 is changed into the polytetramethylene glycol (0.4mol) that the average molecular weight is 1000, the poly(hexamethylene carbonate) (0.4mol) that the average molecular weight is 2000, synthesizes in the same manner as in Example 1 , get PUI-3. As a result of measurement by GPC, Mw=55000 and Mn=25000 in terms of polystyrene. In addition, this polyurethane imide resin was soluble in methyl ethyl ketone at a solid content of 40% by weight.

This PUI-3 was formulated in accordance with Table 1 in the same manner as in Example 1 to obtain a film-like adhesive having an adhesive layer thickness of 20 μm.

Comparative example 1

Instead of PUI-1, a phenoxy resin (PKHC, trade name manufactured by Unionka-Bide Co., Ltd., average molecular weight 45,000, methyl ethyl ketone solution (solid content 40% by weight)) was used, and a film was obtained in the same manner as in Example 1. adhesive.

Comparative example 2

Instead of PUI-1, polyvinyl butyral resin (3000K, trade name manufactured by Denki Kagaku Kogyo Co., Ltd., average degree of polymerization 800, methyl ethyl ketone solution (solid content 40% by weight)), and Example 1 A film-like adhesive was obtained in the same manner.

Determination of Adhesive Strength

Using the film-like adhesive obtained by the above-mentioned manufacturing method, a 2-layer flexible printed circuit board ( FPC) and glass (thickness 1.1mm, surface resistance 20Ω/□) formed with a thin layer of 0.2μm indium tin oxide (ITO), using a thermocompression bonding device (heating method: constant heating type (Constant ヒ one ト), (manufactured by Toray Engineering Co., Ltd.) was heated and pressed at 170°C and 3 MPa for 20 seconds, and the entire width was 2 mm to connect to prepare a connected body.

The adhesive strength of the obtained connected body was measured and evaluated by the 90 degree peeling method according to JIS-Z0237 standard. Here, the measuring device of the adhesive strength used Tension UTM-4 (peeling speed 50 mm/min, 25 degreeC) manufactured by Toyo Body Win Co., Ltd..

The results of the measurements performed above are summarized in Table 1.

Table 1

project Example 1 Example 2 Example 3 Comparative example 1 Comparative example 2 PUI-1 80 PUI-2 80 PUI-3 80 PKHC 80 3000K 80 U-108 20 20 20 20 20 TMN 3 3 3 3 3 Adhesive strength (N/m) 580 500 600 100 150

In Examples 1 to 3 of the adhesive composition using the polyurethane-imide resin represented by the general formula (I) of the present invention, the adhesive strength was high. In contrast, in Comparative Example 1 using a phenoxy resin and Comparative Example 2 using a polyvinyl butyral resin, the adhesive strength deteriorated.

Similarly, the same effect can be obtained by including an epoxy resin and a latent curing agent in the three-dimensional crosslinkable resin.

As mentioned above, the polyurethane-imide resin of this invention and the adhesive composition containing this polyurethane-imide resin are suitable for the adhesive agent for circuit connection or semiconductor encapsulation excellent in adhesive force. In addition, according to the present invention, it is possible to provide a product that can be connected at a low temperature, shortens the connection time, and has an excellent adhesive force that can cope with the narrowing of the electrode width and electrode interval due to the increase in the density of the circuit. The characteristic adhesive composition, and the adhesive composition for circuit connection using this adhesive composition, these adhesive compositions are also excellent in connection reliability.

Claims (13)

1. A polyurethane-imide resin represented by general formula (I), In formula (I), R ¹ is a divalent organic group containing an aromatic ring or an aliphatic ring, R ² is a diol residue with a molecular weight of 500-10,000 without an aromatic ring, and R ³ is a divalent alcohol residue containing 4 or more A carbon tetravalent organic group, n and m are integers ranging from 1 to 100. 2. The polyurethane-imide resin according to claim 1, which is characterized in that it is block copolymerized after chain extension of polyurethane oligomers obtained from diisocyanates and diols with tetracarboxylic dianhydrides thing. 3. polyurethane-imide resin according to claim 1, is characterized in that, in general formula (I), 10mol%～100mol% ^of R has the structure represented with following general formula (II), 4. polyurethane-imide resin according to claim 1, is characterized in that, in above-mentioned general formula (I), 10mol%～100mol% of ^R2 is to be made up of the repeating unit represented by following general formula (III) The average molecular weight is 500-10000 diol residues without aromatic rings, -(CH ₂ -CH ₂ -CH ₂ -CH ₂ -O)- (III) 5. The polyurethane-imide resin according to claim 1, which has an average molecular weight of 5,000 to 500,000 and is soluble in a ketone-based solvent. 6. An adhesive composition containing the polyurethane-imide resin according to claim 1. 7. The adhesive composition according to claim 6, further comprising a three-dimensional crosslinkable resin. 8. The adhesive composition according to claim 6, wherein the polyurethane-imide resin is a block copolymer obtained by chain-extending a polyurethane oligomer with tetracarboxylic dianhydride. 9. The adhesive composition according to claim 7, wherein the polyurethane-imide resin is a block copolymer obtained by chain-extending a polyurethane oligomer with tetracarboxylic dianhydride. 10. The adhesive composition according to claim 7, wherein the three-dimensional cross-linkable resin is at least a free-radical polymer and contains a curing agent that generates free radicals by light irradiation or heating. 11. The adhesive composition according to claim 7, wherein the three-dimensional crosslinkable resin is at least an epoxy resin and contains a latent curing agent. 12. The adhesive composition according to any one of claims 6 to 11, further comprising conductive particles. 13. An adhesive composition for circuit connection, wherein the adhesive composition according to any one of claims 6 to 12 is used for a member for circuit connection.