JP2005162945A - Heat-resistant resin composition and resin and adhesive film produced therefrom - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a heat-resistant resin composition keeping excellent adhesiveness and sufficiently high heat-resistance and imparting an adhesive with properties to reduce the production cost without giving adverse effect on the environment and human bodies. <P>SOLUTION: The heat-resistant resin composition contains a polyamide imide resin and a thermosetting resin. The cured film obtained by the thermal curing of the heat-resistant resin composition has a storage modulus of ≥1 GPa at 25-250°C, a thermal expansion coefficient of ≤0.5×10<SP>-3</SP>/K and an internal stress of ≤30 MPa. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a heat resistant resin composition, a resin obtained therefrom, and an adhesive film.

  In recent years, as the mounting density of electronic components has increased with the development of electronic devices, there has been a demand for downsizing, lightening, and increasing the density of electronic components. In order to satisfy these requirements, it is necessary to reduce the thickness and the mounting area of electronic component materials such as wiring boards, adhesives, and semiconductor chips.

  Along with the miniaturization and high density of electronic components, the circuit of the wiring board has been miniaturized, and an adhesive having a strong adhesive force with a metal foil with a small rough shape and excellent heat resistance is required. It became so. However, epoxy resins that have been used for adhesives have poor heat resistance, and polyamic acid, a mixture of polyamic acid and bismaleimide, and polyimide resin are excellent in heat resistance but have a curing temperature of 300 ° C. to 400 ° C. Furthermore, the adhesive strength with the metal foil was insufficient.

As compared with these resins, a polyamide-imide resin has attracted attention as an adhesive exhibiting stable high adhesiveness regardless of the type and shape of the adherend and having high heat resistance. As such a polyamideimide resin, for example, a polyamideimide resin in which an organopolysiloxane structure is introduced into the main chain (see Patent Document 1), and a polyamideimide resin having an organopolysiloxane structure in which an aramid structure is introduced (Patent Document) 2) is known.
Japanese Patent Laid-Open No. 10-60111 JP 2000-239340 A

  However, the present inventors have studied in detail the conventional polyamideimide resin described in Patent Documents 1 and 2 described above, and those described in Patent Document 1 have a low elastic modulus at a relatively high temperature and are heat resistant. We found that there is a problem that the nature is insufficient.

  In addition, the polyamideimide resin described in Patent Document 2 is excellent in heat resistance. However, when a heat treatment is performed after an adhesive containing the resin is applied to a film or the like when manufacturing a wiring board, It has been found that there is a problem that thermal stress is generated between the adherend and the adhesive, and the wiring board is warped.

  Further, these polyamideimide resins are usually used after being dissolved in an organic solvent. For example, when producing an adhesive film, the adhesive film is obtained by applying an adhesive containing a polyamideimide resin dissolved in an organic solvent. Is made. Therefore, it is necessary to volatilize the organic solvent in the end, but since these organic solvents affect the environment and people, it is preferable to refrain from using them. It has also been found that the use of such an organic solvent leads to an increase in production cost because the organic solvent is forcibly removed by heating or the like in order to shorten the production process.

  Therefore, the present invention has been made in view of the above circumstances, maintains excellent adhesiveness, has sufficiently high heat resistance, and can reduce manufacturing costs without affecting the environment and the human body. An object of the present invention is to provide a heat-resistant resin composition for imparting to an adhesive, a resin obtained therefrom, and an adhesive film.

  As a result of intensive studies to achieve the above object, the present inventors have found that the heat resistant resin composition contains a specific resin, and the resin obtained from the heat resistant resin composition has predetermined physical properties. If so, the inventors have found that all of the above characteristics can be fully satisfied at the same time, and have completed the present invention.

That is, the heat resistant resin composition of the present invention contains a polyamideimide resin and a thermosetting resin, and is a cured film obtained by thermosetting the heat resistant resin composition at 25 to 250 ° C. The storage elastic modulus is 1 GPa or more, the thermal expansion coefficient is 0.5 × 10 ⁻³ / K or less, and the internal stress is 30 MPa or less.

Here, the storage elastic modulus and the glass transition temperature described later are physical properties of the heat-resistant resin composition measured using a dynamic viscoelasticity measuring device (DMA), and the thermal expansion coefficient is a thermomechanical analyzer ( It is a physical property value of a heat-resistant resin composition measured using TMA). Further, the glass transition temperature Tg, when any temperature below the Tg represents the T _1, the internal stress σ of the heat-resistant resin composition in that T _1, the thermal expansion coefficient at T ₁ alpha, storage at T ₁ elastic The ratio is obtained from the following formula (13), where E is the rate.
σ = αE (Tg−T ₁ ) (13)

  The heat-resistant resin composition having such physical properties can sufficiently suppress the generation of thermal stress due to adhesion with the conductor layer even when heated to 250 ° C. in a state where it is applied to the conductor layer. . In addition, since excellent adhesiveness is maintained and no organic solvent is used, the environment or human body is not affected, and the manufacturing cost is reduced.

  In addition, the heat-resistant resin composition is preferably such that the polyamideimide resin contained therein is in a solid powder form and the thermosetting resin is in a liquid state. Thereby, since those inclusions are mixed more uniformly, the entire resin obtained by curing the heat-resistant resin composition has the above-described physical properties. Therefore, since it is no longer necessary to contain an organic solvent that has been used in the case of using this type of conventional heat-resistant resin composition as an adhesive or the like, there is no influence on the environment and the human body, and the manufacturing cost is reduced. It becomes possible to reduce.

  Furthermore, if the heat resistant resin composition contains 10 to 100 parts by mass of the thermosetting resin with respect to 100 parts by mass of the polyamideimide resin, it is preferable because it can have excellent curability.

In addition, the heat-resistant resin composition is obtained by adding trimellitic anhydride to a mixture of a diamine having 3 or more aromatic rings in the molecule, a polyoxypropylene diamine, and a siloxane diamine. A first reaction step of reacting a diimide dicarboxylic acid (A) represented by the following general formula (1) obtained by the first reaction step, and a diimide dicarboxylic acid (B) represented by the following general formula (4) And a second reaction step in which an aromatic diisocyanate represented by the following general formula (8) is reacted with a mixture of the diimide dicarboxylic acid (C) represented by the following general formula (6): It is preferable that it is obtained by the production method.

In formula (1), R ¹ represents a group represented by the following general formula (2), and in formula (2), X represents the following formulas (3a), (3b), (3c), ( The group represented by 3d), (3e), (3f), (3g) or (3h) is shown.

In the formula (4), ^{R 2} represents a group represented by the following general formula (5), wherein (5), m is an integer of 1 to 70.

Further, in formula (6), R ³ represents a group represented by the following general formula (7), and in formula (7), R ⁴ and R ⁵ each independently represents a divalent organic group, R ⁶ , R ⁷ , R ⁸ and R ⁹ each independently represent an alkyl group having 1 to 20 carbon atoms or an aryl group having 6 to 18 carbon atoms, and n represents an integer of 1 to 50.

In the formula (8), R ¹⁰ represents a group represented by the following formula (9a), (9b), (9c), (9d) or (9e).

  The heat-resistant resin composition has a sufficiently high elastic modulus at a high temperature and a sufficiently high glass transition temperature (Tg) by containing a polyamideimide resin synthesized using a raw material having such a chemical structure. Can do. Therefore, it is possible to prevent destruction of the adhesive surface due to thermal stress, and it is possible to realize high adhesion even on a smooth surface with a small roughened shape.

  Moreover, when the said polyoxypropylene diamine has an amine equivalent of 100-2000 g / mol, since generation | occurrence | production of a thermal stress can fully be suppressed and adhesiveness can further be improved, it is preferable.

  Moreover, when the said siloxane diamine has an amine equivalent of 400-2500 g / mol, since the adhesive force with respect to the conductor of the resin obtained can be improved especially, it is desirable.

  Furthermore, it is particularly preferable from the viewpoint of curability that the heat-resistant resin composition further contains an epoxy resin curing accelerator and / or a curing agent, and further contains an epoxy resin as a thermosetting resin.

  The adhesive film of the present invention is characterized by comprising the above-described heat-resistant resin composition. Even if this adhesive film is bonded to a conductor such as a metal foil and subjected to heat treatment, the generation of thermal stress between them can be sufficiently suppressed, so that the occurrence of warpage is reduced.

  The curable resin of the present invention is obtained by thermosetting the heat-resistant resin composition as described above. Since such a cured resin has sufficiently excellent adhesion and heat resistance, it is particularly effective when used in the production of electronic components.

  According to the present invention, a heat-resistant resin composition that maintains excellent adhesiveness, has sufficiently high heat resistance, and further imparts properties to the adhesive that can reduce manufacturing costs without affecting the environment and the human body. Products and resins obtained therefrom and adhesive films can be provided.

  Hereinafter, preferred embodiments of the present invention will be described in detail.

The heat resistant resin composition of the present invention contains a polyamideimide resin and a thermosetting resin in a uniformly dispersed state, and is a cured film obtained by thermosetting the heat resistant resin composition. The storage elastic modulus at 25 to 250 ° C. is 1 GPa or more, the thermal expansion coefficient is 0.5 × 10 ⁻³ / K or less, and the internal stress is 30 MPa or less.

(Polyamideimide resin)
The polyamide-imide resin contained in the heat-resistant resin composition is not particularly limited as long as it can give the above-described properties to a resin obtained by thermosetting the heat-resistant resin composition. Can be used. Among them, a first reaction step in which trimellitic anhydride is reacted with a mixture of a diamine having three or more aromatic rings in the molecule, a polyoxypropylene diamine, and a siloxane diamine is obtained by the first reaction step. It is preferable to be obtained by a method for producing a polyamide-imide resin comprising a second reaction step in which an aromatic diisocyanate is reacted with a mixture of diimide dicarboxylic acids (A) to (C).

  The polyamideimide resin thus obtained is a cured resin (hereinafter referred to as “cured resin”) obtained by heat-treating a heat-resistant resin composition containing the polyamideimide resin even at a high temperature of about 250 ° C. Since the elastic modulus is maintained sufficiently high, the cured resin can adhere sufficiently firmly even to a conductor surface such as a metal foil that is not so roughened.

  In addition, since the cured resin has a sufficiently high glass transition temperature, it can sufficiently suppress the generation of thermal stress between the cured resin and the conductor even when a sudden temperature change is applied after the resin is bonded onto the conductor surface. Can do. Therefore, components such as a wiring board provided with such a cured resin and a conductor tend not to be deformed such as warpage.

  Examples of the diamine having three or more aromatic rings in the molecule used in the first reaction step include 2,2-bis [4- (4-aminophenoxy) phenyl] propane (hereinafter abbreviated as BAPP), Bis [4- (3-aminophenoxy) phenyl] sulfone, 2,2-bis [4- (4-aminophenoxy) phenyl] hexafluoropropane, bis [4- (4-aminophenoxy) phenyl] methane, 4, 4′-bis (4-aminophenoxy) biphenyl, bis [4- (4-aminophenoxy) phenyl] ether, bis [4- (4-aminophenoxy) phenyl] ketone, 1,3-bis (4-aminophenoxy) ) Benzene or 1,4-bis (4-aminophenoxy) benzene.

  Among these, BAPP is more preferable from the viewpoint of the balance of properties of the polyamideimide resin and cost. These may be used alone or in combination of two or more.

で表されるものが挙げられる。なお、式（１０）中、ｍは１〜７０の整数を示す。 Polyoxypropylene diamine can be used without limiting what is conventionally known. Specifically, for example, the following general formula (10);

The thing represented by is mentioned. In formula (10), m represents an integer of 1 to 70.

  Such polyoxypropylene diamine can also be obtained commercially. Examples of commercially available products include Jeffamine D-230 (Sun Techno Chemical Co., amine equivalent: 115, trade name), Jeffamine D-400 (Sun Techno Chemical Co., amine equivalent: 200, trade name), Jeffamine D-2000 (Sun Techno Chemical Co., Ltd., amine equivalent: 1,000, trade name), Jeffamine D-4000 (Sun Techno Chemical Co., amine equivalent: 2000, trade name) and the like can be mentioned. These can be used alone or in combination of two or more.

  The polyoxypropylene diamine preferably has an amine equivalent of 100 to 2000 g / mol, more preferably has an amine equivalent of 500 to 1500 g / mol, and particularly preferably has an amine equivalent of 700 to 1200 g / mol. By using polyoxypropylene diamine having an amine equivalent weight within the above range, when the obtained heat-resistant resin composition is used in a laminate, etc., it is effective in generating warpage after being applied to a film or the like and dried. Can be reduced. Furthermore, adjusting the amine equivalent within the above numerical range is preferable from the viewpoint of improving adhesiveness.

  The “amine equivalent” in the present invention refers to the mass (g) of a resin (compound) containing 1 mol of an amino group.

なお、式（１１）中、Ｒ^１１、Ｒ^１２はそれぞれ独立に二価の有機基を示し、Ｒ^１３、Ｒ^１４、Ｒ^１５及びＲ^１６はそれぞれ独立に炭素数１〜２０のアルキル基又は炭素数６〜１８のアリール基を示し、ｎは１〜５０の整数を示す。 Siloxane diamine can be used without limiting what is conventionally known. Examples of the siloxane diamine include those represented by the following general formula (11).

In formula (11), R ¹¹ and R ¹² each independently represent a divalent organic group, and R ¹³ , R ¹⁴ , R ¹⁵ and R ¹⁶ each independently represent an alkyl group having 1 to 20 carbon atoms or carbon The aryl group of number 6-18 is shown, n shows the integer of 1-50.

  In formula (11), examples of the divalent organic group include an alkylene group such as a methylene group, an ethylene group or a propylene group, or an arylene group such as a phenylene group, a tolylene group or a xylylene group.

なお、式（１２ａ）、（１２ｂ）、又は（１２ｃ）中、ｎは、１〜５０の整数を示す。 More specifically, examples of such siloxane diamine include those represented by the following general formula (12a), (12b), or (12c).

In addition, in formula (12a), (12b), or (12c), n shows the integer of 1-50.

  Such siloxane diamine can also be obtained commercially. Examples of commercially available products include amino-modified silicone oil X-22-161AS (manufactured by Shin-Etsu Chemical Co., Ltd., amine equivalent 450, trade name), X-22-161A (manufactured by Shin-Etsu Chemical Co., Ltd., amine equivalent). 840, trade name), X-22-161B (Shin-Etsu Chemical Co., Ltd., amine equivalent 1500, trade name), BY16-853 (Toray Dow Corning Silicone Co., Ltd., amine equivalent 650, trade name) or BY16-853B (Toray Dow Corning Silicone Co., Ltd., amine equivalent 2200, trade name). These may be used alone or in combination of two or more.

  The siloxane diamine preferably has an amine equivalent of 400 to 2500 g / mol, more preferably has an amine equivalent of 1000 to 2000 g / mol, and particularly preferably has an amine equivalent of 1300 to 1700 g / mol. By using a siloxane diamine having an amine equivalent within the above range, the adhesiveness of the resulting heat-resistant resin composition tends to be further improved.

  In the first reaction step, an aprotic polar solvent can also be used. The aprotic polar solvent is preferably an organic solvent that does not react with the diamine having three or more aromatic rings in the molecule, polyoxypropylene diamine, siloxane diamine, and trimellitic anhydride. Specific examples include dimethylacetamide, dimethylformamide, dimethyl sulfoxide, N-methyl-2-pyrrolidone, γ-butyrolactone, sulfolane, and cyclohexanone. Since the imidization reaction in the first reaction step requires high temperature, among these, it is more preferable to use N-methyl-2-pyrrolidone having a high boiling point. These may be used alone or in combination of two or more.

  The aprotic polar solvent preferably has a moisture content of 0.2% by mass or less. If this water content exceeds 0.2% by mass, the presence of trimellitic acid produced by hydration of trimellitic anhydride does not sufficiently advance the reaction, and the molecular weight of the polyamideimide resin tends to decrease. .

  The mixing ratio of each diamine described above is preferably as follows when the total amount thereof is 100 mol%. That is, the diamine having 3 or more aromatic rings in the molecule is preferably mixed in an amount of 0.0 to 70.0 mol%, and more preferably 0.0 to 65.0 mol%. Moreover, it is preferable that 10.0-70.0 mol% of polyoxypropylene diamine is mixed, and it is more preferable that 20.0-60.0 mol% is mixed. Furthermore, it is preferable that 10.0-50.0 mol% of siloxane diamine is mixed, and it is preferable that 10.0-40.0 mol% is mixed. When a mixture with a mixing ratio outside the preferred numerical range is used, the resulting heat resistant resin composition tends to cause warping of the wiring board, or the molecular weight of the polyamideimide resin tends to decrease.

  Moreover, the compounding ratio of trimellitic anhydride to the mixture of these diamines is preferably 2.05 to 2.20, more preferably 2.10 to 2.20 in terms of molar ratio. If this molar ratio is less than 2.05, diamine remains, and the molecular weight of the finally obtained polyamideimide resin tends to decrease. On the other hand, when the molar ratio exceeds 2.20, trimellitic anhydride remains, and the molecular weight of the finally obtained polyamideimide resin tends to decrease.

  Further, the blending amount of the aprotic polar solvent described above is the total amount of diamine having 3 or more aromatic rings in the molecule, polyoxypropylene diamine, siloxane diamine, trimellitic anhydride and the aprotic polar solvent and other raw materials. It is preferable to adjust so that it may become 10-80 mass% with respect to 100 mass%, and it is more preferable when it adjusts so that it may become 50-80 mass%. If the blending amount of the aprotic polar solvent is less than 10% by mass, the solubility of trimellitic anhydride is lowered, so that the reaction does not proceed sufficiently. Moreover, when the compounding quantity exceeds 80 mass%, it will become disadvantageous as an industrial manufacturing method.

  In the first reaction step, it is preferable to use an aromatic hydrocarbon that can be azeotroped with water. Specific examples include benzene, xylene, ethylbenzene, and toluene. Among these, toluene having a relatively low boiling point and less harmful to the working environment is particularly preferable. The amount of the aromatic hydrocarbon used is preferably in the range of 0.1 to 0.5 mass ratio (10 to 50 mass%) of the aprotic polar solvent.

  In the first reaction step, by reacting trimellitic anhydride with a mixture of a diamine having three or more aromatic rings in the molecule, a polyoxypropylene diamine, and a siloxane diamine, the above general formula (1), Diimide dicarboxylic acids (A) to (C) represented by (4) and (6) are obtained.

Among these, examples of the alkyl group having 1 to 20 carbon atoms (R ^{6 to} R ⁹ ) in the molecule of diimide dicarboxylic acid (C) include, for example, methyl group, ethyl group, n-propyl group, isopropyl group, n -Butyl group, isobutyl group, sec-butyl group, tert-butyl group, pentyl group, isopentyl group, neopentyl group, hexyl group, heptyl group, octyl group, nonyl group, decyl group, undecyl group, dodecyl group, tridecyl group, Examples include tetradecyl group, pentadecyl group, hexadecyl group, heptadecyl group, octadecyl group, nonadecyl group, icosyl group, and structural isomers thereof.

Further, diimide dicarboxylic acid (C) is the aryl group having 6 to 18 carbon atoms ^(R 6 ~R ⁹⁾ having in the molecule, for example, a phenyl group, a naphthyl group, and anthryl group or phenanthryl group. Moreover, the aromatic ring hydrogen atom of these aryl groups may be substituted with a halogen atom, an amino group, a nitro group, a cyano group, a mercapto group, an allyl group or an alkyl group having 1 to 20 carbon atoms.

  In the second reaction step, a desired polyamide-imide resin can be obtained by reacting an aromatic diisocyanate with a mixture of the diimide dicarboxylic acids (A) to (C).

  In the second reaction step, an aromatic dicarboxylic acid or an aliphatic dicarboxylic acid can be used in addition to the diimide dicarboxylic acids (A) to (C) from the viewpoint of heat resistance. Examples of the aromatic dicarboxylic acid include terephthalic acid, phthalic acid, and naphthalenedicarboxylic acid. Examples of the aliphatic carboxylic acid include adipic acid, sebacic acid, decanedioic acid, dodecanedioic acid, and dimer acid. Etc. The blending amount is preferably about 5 to 10 mol% with respect to 100 mol% of the total amount of dicarboxylic acid.

  As aromatic diisocyanate, what is represented by the said General formula (8) is preferable. Specific examples of such aromatic diisocyanates include, for example, 4,4′-diphenylmethane diisocyanate (hereinafter abbreviated as MDI), 2,4-tolylene diisocyanate (hereinafter abbreviated as TDI), and 2,6-tolylene diisocyanate. , Naphthalene-1,5-diisocyanate or 2,4-tolylene dimer.

  Among these, 4,4'-diphenylmethane diisocyanate is more preferable from the viewpoint of imparting flexibility to the cured resin and preventing crystallinity. These may be used alone or in combination of two or more.

  In addition to the above aromatic diisocyanate, aliphatic diisocyanate can also be used from the viewpoint of heat resistance. Examples of the aliphatic diisocyanate include hexamethylene diisocyanate, 2,2,4-trimethylhexamethylene diisocyanate, and isophorone diisocyanate. The blending amount is preferably about 5 to 10 mol% with respect to 100 mol% of the total amount of diisocyanate.

  The mixing ratio of the above-mentioned aromatic diisocyanate and optionally added aliphatic diisocyanate to the mixture of diimide dicarboxylic acid (A) to (C) and optionally added aromatic dicarboxylic acid and aliphatic carboxylic acid, The molar ratio is preferably 1.05 to 1.50, more preferably 1.10 to 1.30. If the molar ratio is less than 1.05, the molecular weight of the polyamideimide resin tends to decrease, and even if the molar ratio exceeds 1.50, the molecular weight of the polyamideimide resin tends to decrease. Therefore, the formability and flexibility of the film provided with them tend to decrease.

  The weight average molecular weight (Mw) of the polyamideimide resin obtained through the first reaction step and the second reaction step is preferably 30,000 to 300,000, more preferably 40000 to 200,000, and particularly preferably 50,000 to 100,000. preferable. When the weight average molecular weight is less than 30000, the strength and flexibility in the state of forming a film using the polyamideimide resin tend to decrease, and the tackiness increases and the micro-layer separation structure tends to disappear. is there. When the weight average molecular weight exceeds 300,000, flexibility and adhesiveness in a state where a film is formed tend to be lowered. In addition, the weight average molecular weight in this invention is measured by the gel permeation chromatography method, and is converted with the analytical curve created using standard polystyrene.

  More specifically, the above-described polyamideimide resin is produced by the following method, for example.

  First, in the first reaction step, a mixture of diamine having three or more aromatic rings in the molecule, polyoxypropylene diamine and siloxane diamine, and trimellitic anhydride are mixed, and the aprotic polar solvent described above is further added. Added.

  And these are heated to reaction temperature of 50-90 degreeC, and are made to react about 0.2 to 1.5 hours. When the reaction temperature is lower than 50 ° C., the reaction tends to be slow and industrially disadvantageous, and at a temperature higher than 150 ° C., the reaction with a carboxyl group that does not cyclize proceeds to generate an imide. There is a tendency to be disturbed.

  Next, the above-described aromatic hydrocarbon capable of azeotroping with water is further added, and the reaction system is heated to 120 to 180 ° C. In the first reaction step, the reaction of the diamine mixture and trimellitic anhydride is considered to form an imide bond by dehydrating and closing the anhydrous portion of trimellitic anhydride once the ring is opened. Is preferably carried out at the end of the first reaction step by adding an aromatic hydrocarbon azeotropic with water to the resulting reaction mixture and raising the temperature. By adding an aromatic hydrocarbon azeotropic with water to the reaction mixture, water generated by the dehydration ring-closing reaction can be efficiently removed.

  At this time, when the reaction temperature is lower than 120 ° C., water tends not to be sufficiently removed, and when the reaction temperature is higher than 180 ° C., dissipation of aromatic hydrocarbons tends not to be prevented.

  The dehydration cyclization reaction is preferably carried out until no water is generated. Completion of the dehydration ring-closing reaction can be carried out, for example, by confirming that a theoretical amount of water has been distilled off with a moisture determination receiver or the like.

  In this way, the first reaction step is completed, and the above-described diimide dicarboxylic acids (A) to (C) are obtained.

  In addition, it is preferable to remove the aromatic hydrocarbon azeotropic with water before the second reaction step. In the state containing aromatic hydrocarbons, the product polyamideimide may precipitate during the reaction. The method for removing the aromatic hydrocarbon is not particularly limited. For example, there is a method in which the aromatic hydrocarbon is distilled off by further raising the temperature after the dehydration ring-closing reaction.

  Subsequently, in the second reaction step, the above-mentioned aromatic diisocyanate is added to diimide dicarboxylic acid (A) to (C), and further, if necessary, the above-mentioned aromatic dicarboxylic acid or aliphatic dicarboxylic acid and aliphatic diisocyanate are added. The mixture is added and reacted at a reaction temperature of 150 to 250 ° C. for about 0.5 to 3 hours.

  If the reaction temperature is less than 150 ° C., the reaction time tends to be longer. If the reaction temperature exceeds 250 ° C., the reaction between diisocyanates occurs, the reaction efficiency decreases, and the elastic modulus and mechanical strength of the resulting polyamideimide resin decrease. Tend.

  In the second reaction step, a small amount of other by-products of the diimidedicarboxylic acid (A) to (C) generated in the first reaction step may be included within a range that does not affect the final performance. In addition, the solvent used in the first reaction step can be used as it is. From this, the reaction mixture after the first reaction step can be used in the second reaction step without particularly performing an isolation operation, and the reaction operation can be simplified.

  In this way, the second reaction step is completed, and a desired polyamideimide resin can be obtained.

  After completion of the reaction, for example, the reaction product is put into methanol to precipitate a resin component, and further filtered to take out the deposited resin component and remove the residual solvent at a temperature of about 50 ° C. Thus, a solid polyamideimide resin is obtained.

(Thermosetting resin)
The thermosetting resin according to the present invention can be used without particular limitation as long as it has a functional group that reacts with the amide group in the polyamide-imide resin. Specifically, for example, an epoxy resin, a polyimide resin, an unsaturated polyester resin, a polyurethane resin, a bismaleimide resin, a triazine-bismaleimide resin, a phenol resin, or the like can be given.

  Among these, an epoxy resin having an epoxy group is particularly preferable from the viewpoint of improving thermal characteristics, mechanical characteristics, and electrical characteristics, being excellent in adhesiveness, and handling. These may be used alone or in combination of two or more.

  Examples of the epoxy resin include polyepoxy ethers, polyepoxy esters, amines, amides, N-epoxy derivatives of compounds having a heterocyclic nitrogen base, and alicyclic epoxy resins. The polyepoxy ether can be obtained by reacting a polyhydric alcohol such as bisphenol A, a novolac type phenol resin or an orthocresol novolac type phenol resin or a polyhydric alcohol such as 1,4-butanediol with epichlorohydrin. The polyepoxy ester can be obtained by reacting a polybasic acid such as phthalic acid or hexahydrophthalic acid with epichlorohydrin.

  Examples of the bifunctional epoxy resin include bisphenol A type or bisphenol F type epoxy resin. Examples of the bisphenol A-type or bisphenol F-type liquid epoxy resin include Epicoat 807, Epicoat 827, and Epicoat 828 (trade name, manufactured by Yuka Shell Epoxy Co., Ltd.), D.I. E. R. 331, D.D. E. R. 337 or D.I. E. R. 359 (above, product name manufactured by Dow Chemical Japan Co., Ltd.), Epic R140P or Epomic R110 (above, product name made by Mitsui Petrochemical Co., Ltd.), or YD8125 or YDF8170 (above, product name made by Toto Kasei Co., Ltd.) Etc. can be illustrated.

  Examples of the polyfunctional epoxy resin having 3 or more epoxy groups include phenol novolac type epoxy resins and cresol novolac type epoxy resins. Examples of the phenol novolac type epoxy resin include EPPN-201 (manufactured by Nippon Kayaku Co., Ltd.). Examples of the cresol novolac type epoxy resin include ESCN-195 or ESCN-220 (above, manufactured by Sumitomo Chemical Co., Ltd., products). Name), EOCN1020, EOCN4400, or EOCN102S (above, Nippon Kayaku Co., Ltd., trade name), YDCN701, YDCN702, YDCN500-2, YDCN500-10 (above, Toto Kasei Co., Ltd., trade name), and the like. These may be used alone or in combination of two or more.

  An epoxy resin containing a phosphorus atom in the skeleton can also be used. Use of a phosphorus-containing epoxy resin is preferable in that flame retardancy can be imparted to the composition. Examples of the phosphorus-containing epoxy resin include ZX-1548-1, ZX-1548-2, or ZX-1548-3 (above, manufactured by Tohto Kasei Co., Ltd., trade name).

  The epoxy equivalent of such an epoxy resin preferably takes into account that the epoxy group of the resin reacts with the amide group of the polyamideimide resin. Therefore, the epoxy equivalent is preferably 150 to 250, and more preferably 160 to 200.

  The polyamide-imide resin and thermosetting resin described above are preferably dispersed uniformly in the heat-resistant resin composition. Thereby, it becomes possible to have excellent adhesiveness, electrical characteristics, mechanical characteristics, thermal characteristics, and the like over the entire cured resin.

  Further, when an adhesive using the heat resistant resin composition is adhered to an adherend such as a conductor and heated, warping or the like may occur if a large thermal stress is generated in a part thereof. However, when the above-described resin is uniformly dispersed in the heat-resistant resin composition, generation of a large thermal stress is suppressed only in a part, and thus occurrence of warpage or the like can be sufficiently reduced. .

  In order to uniformly disperse these resins in the heat-resistant resin composition, the polyamide-imide resin is in a powder form (particle diameter is about 1 mm or less), and the temperature at which the thermosetting resin is mixed (usually Preferably, it is liquid at room temperature. Thereby, it becomes possible to disperse | distribute efficiently and uniformly by heat-melting the composition.

  More preferably, the polyamideimide resin powder has a particle size of 100 μm or less. When the particle diameter exceeds 100 μm, even if heated and melted, there is a tendency that a uniform state is not obtained.

  When using an epoxy resin as a thermosetting resin, you may further add the hardening | curing agent or hardening accelerator which reacts with an epoxy resin in a heat resistant resin composition. As the curing agent, for example, amines, imidazoles, polyfunctional phenols or acid anhydrides can be used, and these also function as curing accelerators.

  Examples of amines that can be used include dicyandiamide, diaminodiphenylmethane, and guanylurea.

  As the phenolic resin and polyfunctional phenols having a hydroxyl group, hydroquinone, resorcinol, bisphenol A and their halogen compounds, and a novolak type phenolic resin or a resol type phenolic resin that is a condensate with formaldehyde can be used. Examples of the phenol resin include Phenolite LF2882, Phenolite LF2822, Phenolite TD-2090, Phenolite TD-2149, Phenolite VH4150, Phenolite VH4170, Pryofen KA-1160 or Pryofen KA-1163 (and larger Nippon Ink Chemical Industries, Ltd., trade name) and the like.

  As the acid anhydrides, phthalic anhydride, benzophenone tetracarboxylic dianhydride, methyl hymic acid, or the like can be used.

  As the imidazole as a curing accelerator, alkyl group-substituted imidazole or benzimidazole can be used. Specific examples include 2-methylimidazole, 2-phenylimidazole, 2-ethyl-4-methylimidazole, 1-cyanoethyl-2-phenylimidazole, 2-phenyl-4-methyl-5-hydroxymethylimidazole, and the like. 2MZ, 2PZ, 2E4MZ, 2PZ-CN, 2P4MHZ (trade name, manufactured by Shikoku Kasei Kogyo Co., Ltd.) and the like.

  Next, the compounding quantity of each component contained in the heat resistant resin composition of this invention is demonstrated.

  In the heat resistant resin composition of this invention, it is preferable to mix | blend 10-100 mass parts of thermosetting resins with respect to 100 mass parts of polyamideimide resins, and it is more preferable to mix | blend 30-80 mass parts. More preferably, 50 parts by mass is blended. When the blending amount of the thermosetting resin is less than 10 parts by mass with respect to 100 parts by mass of the polyamideimide resin, the solvent resistance is poor and the function as the thermosetting resin tends to be lowered. On the other hand, when the amount exceeds 100 parts by mass, the Tg is lowered by the unreacted thermosetting resin and the heat resistance becomes insufficient, or the cross-linked structure of the cured resin becomes dense, and the flexibility tends to be lowered.

  In the case of amines, the compounding amount of the curing agent or curing accelerator is preferably such that the active hydrogen equivalent of the amine and the epoxy equivalent of the epoxy resin are approximately equal. When the curing accelerator is imidazole, the amount is not simply equal to that of active hydrogen, and 0.1 to 2 parts by mass is required with respect to 100 parts by mass of the epoxy resin. If the blending amount of these curing agents and curing accelerators is less than the above lower limit value, the uncured epoxy resin tends to remain and Tg tends to be low. If the upper limit value is exceeded, unreacted curing agents and curing accelerators are present. Residual insulation tends to decrease.

  In addition, polyfunctional phenols and acid anhydrides as curing agents are added for the purpose of cross-linking with the remaining epoxy group residues without reacting with the amide group, so that they are cured in a smaller amount than those described above. The reactivity can be improved.

  Next, application examples of the heat resistant resin composition of the present invention will be described.

  In order to form an adhesive layer using the heat-resistant resin composition of the present invention, for example, it may be applied to an adherend as it is to form an adhesive layer, or an adhesive film provided with an adhesive layer on a supporting substrate. You may form and form the contact bonding layer which consists of this heat resistant resin composition.

  An adhesive film provided with the adhesive layer of the present invention can be produced, for example, by applying a heat-resistant resin composition dispersed on a supporting substrate and then curing it slightly by heating. The heating conditions at this time are preferably such that the reaction rate of the heat resistant resin composition is 20 to 40%. Usually, the heating temperature is more preferably 140 to 150 ° C.

  Examples of the supporting substrate include polyolefin such as polyethylene or polyvinyl chloride, polyester such as polyethylene terephthalate, polycarbonate, tetrafluoroethylene resin film, release paper, and metal such as copper foil and aluminum foil. A foil etc. are mentioned.

  The thickness of the supporting substrate is preferably 10 to 150 μm. In addition, you may perform a mat | matte process, a corona treatment, or a mold release process to a support base material.

  The thickness of the adhesive layer containing the heat resistant resin composition laminated on the support substrate is preferably 5 to 50 μm, and more preferably 10 to 40 μm. In particular, when the adhesive layer is thicker than 50 μm, the residual solvent content increases and the adhesive strength and heat resistance are likely to be reduced.

  Examples of the form of the adhesive film include a sheet shape or a roll shape cut by a certain length. From the viewpoint of storage stability, productivity, and workability, a protective film is further laminated on the surface of the heat-resistant resin composition opposite to the surface that is bonded to the support substrate, and wound into a roll and stored. It is preferable to do.

  Examples of the protective film include polyolefins such as polyethylene and polyvinyl chloride, polyesters such as polyethylene terephthalate, polycarbonates, tetrafluoroethylene resin films, and release paper, as in the case of the support substrate. The thickness of the protective film is more preferably 10 to 100 μm. Further, the protective film may be subjected to mud treatment, corona treatment or mold release treatment.

  The adhesive film of the present invention can be used as, for example, a polyimide film with an adhesive by laminating it on a polyimide film or the like. For example, it can be used as a coverlay film for a flexible wiring board and a base film. Furthermore, it can also be used as a substrate for a flexible wiring board by laminating metal foils.

  In addition, when using an adhesive film, after laminating | stacking, you may remove a support base material, You may remove before laminating | stacking.

  In the present invention, when such an adhesive layer is formed, it is not necessary to use an organic solvent, so that the environment and the human body are not affected. In addition, although the organic solvent needs to be volatilized finally, in the present invention in which such an organic solvent is not used, a step for removing the organic solvent can be omitted, which also reduces the manufacturing cost. Connected.

Such an adhesive layer according to the present invention is finally thermoset and provided on a printed wiring board or the like in a cured resin state. At that time, the adhesive layer has a thermal expansion coefficient of 0.5 × 10 ⁻³ / K or less, a storage elastic modulus of 1 GPa or more, and an internal stress of 30 MPa or less. There is a need. The adhesive layer having such physical properties can maintain excellent adhesiveness and sufficiently suppress deformation due to thermal stress generated on an adhesive surface such as a printed wiring board.

  EXAMPLES Hereinafter, although an Example demonstrates this invention further in detail, this invention is not limited to these Examples.

(Synthesis Examples 1-4)
Into a 1 L separable flask equipped with a 25 mL capacity water meter with a cock connected to a reflux condenser, a thermometer and a stirrer, BAPP (2,2-bis) was used as a diamine having three or more aromatic rings in the molecule. [4- (4-aminophenoxy) phenyl] propane), polyoxypropylene diamine (Jephamine D-2000 (manufactured by Sun Techno Chemical Co., Ltd., amine equivalent: 1000, trade name)), siloxane diamine (reactive silicone oil X- 22-161-B (manufactured by Shin-Etsu Chemical Co., Ltd., amine equivalent: 1540, trade name)), TMA (trimellitic anhydride), and NMP (N-methyl-2-pyrrolidone) and γ as aprotic polar solvents -BL (γ-butyrolactone) was charged at the blending ratio (parts by mass) shown in Table 1, respectively, and 30 minutes at 80 ° C Stir for a while. Next, 100 mL of toluene was added as an aromatic hydrocarbon azeotropic with water, and then the temperature was raised to 160 ° C. and refluxed at that temperature for 2 hours.

  Subsequently, it is confirmed that approximately 3.6 mL or more of water has been stored in the moisture determination receiver, and that the outflow of water stored in the moisture determination receiver has been removed. However, the temperature was raised to about 190 ° C. to remove toluene.

  Thereafter, the solution was returned to room temperature, MDI (4,4′-diphenylmethane diisocyanate) and TDI (2,4-tolylene diisocyanate) were added as aromatic diisocyanates at a blending ratio (parts by mass) shown in Table 1, 190 The reaction was carried out at 2 ° C. for 2 hours.

  After completion of the reaction, the reaction product was gradually added into methanol to precipitate the resin component, and the resin component was taken out by filtration through a 10 μm filter. And after making it dry at 70-80 degreeC for about 1 hour, it grind | pulverizes with a grinder, a large particle is removed using the filter which has a 100 micrometers pore diameter, and the synthesis examples 1-4 which have a particle diameter of 100 micrometers or less in particle diameter A polyamide-imide resin was obtained. In addition, Table 1 shows the weight average molecular weight of the obtained polyamideimide resin.

(Example 1)
The heat resistant resin composition of Example 1 was obtained as follows. That is, 70 parts by mass of the modified polyamide resin of Synthesis Example 1, 30 parts by mass of bisphenol A type phenolic resin (Epomic R-140P, trade name, manufactured by Mitsui Petrochemical Co., Ltd.), 0.15 parts by mass of dicyandiamide and 2- 0.2 mass part of ethyl-4-methylimidazole was mix | blended and it stirred for about 1 hour until each material could be mixed uniformly. Subsequently, the mixture was allowed to stand at room temperature for 24 hours to perform defoaming, whereby the heat resistant resin composition of Example 1 was obtained.

(Examples 2 and 3)
The heat-resistant resin compositions of Examples 2 and 3 were obtained in the same manner as Example 1 except that the polyamideimides of Synthesis Examples 2 and 3 were used instead of the polyamideimide resin of Synthesis Example 1, respectively.

(Comparative Example 1)
The heat resistant resin composition of Comparative Example 1 was obtained in the same manner as in Example 1 except that the polyamideimide of Synthesis Example 4 was used instead of the polyamideimide resin of Synthesis Example 1.

(Comparative Example 2)
The heat resistant resin composition of Comparative Example 2 was obtained without using a polyamideimide resin. That is, first, as materials, 70 parts by mass of the above-described bisphenol A type phenol resin, 30 parts by mass of phenol novolac resin (TD2131, manufactured by Dainippon Ink & Chemicals, Inc., trade name), 2-ethyl-4-methylimidazole 0.2 parts by mass and 1 part by mass of triphenylphosphine were blended, and thereafter, the heat resistant resin composition of Comparative Example 2 was obtained in the same manner as in Example 1.

(Evaluation of warpage after drying)
Each obtained heat-resistant resin composition was applied to a rectangular polyimide film having a thickness of 25 μm (Kapton 100H, manufactured by Toray DuPont Co., Ltd., trade name) so that the thickness after drying was 25 μm. And it dried at 140 degreeC for 5 minute (s), and the sample (100 mm width x 100 mm length) for evaluating the curvature after drying was obtained.

  Each sample was then placed on a horizontal reference surface with the polyimide film on the bottom. At this time, when the sample is warped, the lower surface of the polyimide film is lifted upward from the reference surface. Therefore, the distance of the longest portion of the lower surface from the reference surface is measured. Regarding the evaluation, when the warpage of the sample is not recognized, it is “◯”, when the above-mentioned distance of the polyimide film lower surface from the reference surface is 10 mm or less, it is “△”, and when the distance exceeds 10 mm It was set as “x”. The results are shown in Table 2.

(Adhesive evaluation)
Each heat-resistant resin composition was applied to the above-described polyimide film so that the thickness after drying was 20 μm, and was dried at 140 ° C. for 5 minutes to form a heat-resistant resin composition layer. . Next, the surface of the heat-resistant resin composition layer not bonded to the polyimide film is a roughened surface of a rolled copper foil (BHY-22B-T, manufactured by Nikko Gould Wheel Co., Ltd., trade name) having a thickness of 35 μm. Then, the film was temporarily bonded by hot roll lamination under the conditions of 160 ° C. and 0.5 MPa. Then, the temporarily bonded laminate is put in a dryer set at 200 ° C. and subjected to thermosetting treatment for 2 hours, and the adhesiveness between the heat resistant resin composition layer and the roughened surface of the rolled copper foil, and the heat resistance A sample for evaluating the adhesiveness between the conductive resin composition layer and the polyimide film was obtained.

  Moreover, instead of bonding one surface of the heat-resistant resin composition layer to the roughened surface of the rolled copper foil, except for bonding one surface of the heat-resistant resin composition layer to the glossy surface of the rolled copper foil, the above-mentioned In the same manner as above, a sample for evaluating the adhesion between the heat resistant resin composition layer and the glossy surface of the rolled copper foil was obtained.

  In order to evaluate the adhesiveness, a heat resistant resin is obtained by peeling off a rolled copper foil or polyimide film having a width of 10 mm at a temperature of 25 ° C. at a rate of 50 mm / min at a temperature of 25 ° C. Peel strength (kN / m) between composition layer and rolled copper foil (roughened surface), between heat resistant resin composition layer and rolled copper foil (glossy surface), and between heat resistant resin composition and polyimide film ) Was measured. The results are shown in Table 2.

(Measurement of glass transition temperature)
Each heat-resistant resin composition was applied to a tetrafluoroethylene resin film having a thickness of 50 μm (Naflon tape TOMBO9001, manufactured by Nichias Co., Ltd., trade name) so that the thickness after drying was 20 μm, It was dried at 140 ° C. for 5 minutes to form a heat resistant resin composition layer. Next, it was put in a drier set at 200 ° C., subjected to thermosetting treatment for 2 hours, and then peeled off the tetrafluoroethylene resin film, thereby measuring a glass transition temperature (Tg) sample (5 mm width). × 20 mm length).

  Tg is a dynamic viscoelasticity measuring device (RSA2, manufactured by Rheometric Scientific F.E., trade name), tensile mode, distance between chucks: 22.5 mm, measurement temperature: −50 to It was measured under the conditions of 250 ° C., heating rate: 5 ° C./min and measurement frequency: 10 Hz, and the maximum value of the tan δ peak was adopted. The results are shown in Table 2.

(Measurement of storage modulus)
The storage elastic modulus was measured in the same manner as the Tg measurement described above. The results are shown in Table 2.

(Evaluation of solder heat resistance)
Evaluation of solder heat resistance is performed by immersing a sample in which the above-mentioned heat-resistant resin composition layer and the roughened surface of the rolled copper foil are bonded together in a 300 ° C. solder bath for 3 minutes, This was done by visual observation. When neither swelling nor peeling of the sample was observed, “◯” was given, and when the sample was swollen or peeled, “x” was given. The results are shown in Table 2.

(Measurement of thermal expansion coefficient)
The coefficient of thermal expansion was determined by using the TMA (manufactured by Seiko Denshi Kogyo Co., Ltd.), the tensile mode and the measurement temperature: Measured under conditions of ˜250 ° C. and heating rate: 5 ° C./min. The results are shown in Table 2.

Claims (9)

A heat-resistant resin composition containing a polyamide-imide resin and a thermosetting resin,
The cured film obtained by thermosetting the heat-resistant resin composition has a storage elastic modulus at 25 to 250 ° C. of 1 GPa or more, a thermal expansion coefficient of 0.5 × 10 ⁻³ / K or less, and an internal stress of 30 MPa or less. The heat resistant resin composition characterized by the above-mentioned.   The heat-resistant resin composition according to claim 1, wherein the polyamide-imide resin is in a solid powder form, and the thermosetting resin is liquid.   The heat-resistant resin composition according to claim 1 or 2, comprising 10 to 100 parts by mass of the thermosetting resin with respect to 100 parts by mass of the polyamideimide resin. A first reaction step in which the polyamideimide resin is reacted with trimellitic anhydride to a mixture of a diamine having three or more aromatic rings in the molecule, a polyoxypropylene diamine, and a siloxane diamine;
Diimide dicarboxylic acid (A) represented by the following general formula (1) obtained by the first reaction step;

(In formula (1), R ¹ represents a group represented by the following general formula (2).)

(In the formula (2), X represents a group represented by the following formula (3a), (3b), (3c), (3d), (3e), (3f), (3g) or (3h). .)

Diimide dicarboxylic acid (B) represented by the following general formula (4);

(In formula (4), R ² represents a group represented by the following general formula (5).)

(In formula (5), m represents an integer of 1 to 70.)
Diimide dicarboxylic acid (C) represented by the following general formula (6);

(In formula (6), R ³ represents a group represented by the following general formula (7).)

(In Formula (7), R ⁴ and R ⁵ each independently represent a divalent organic group, and R ⁶ , R ⁷ , R ⁸ and R ⁹ are each independently an alkyl group having 1 to 20 carbon atoms or An aryl group having 6 to 18 carbon atoms, and n represents an integer of 1 to 50.)
Into a mixture of
A second reaction step of reacting an aromatic diisocyanate represented by the following general formula (8);

(In formula (8), R ¹⁰ represents a group represented by the following formula (9a), (9b), (9c), (9d) or (9e)).

The heat-resistant resin composition according to claim 1, wherein the heat-resistant resin composition is obtained by a method for producing a polyamideimide resin containing   The heat-resistant resin composition according to claim 4, wherein the polyoxypropylenediamine has an amine equivalent of 100 to 2000 g / mol.   The heat-resistant resin composition according to claim 4 or 5, wherein the siloxane diamine has an amine equivalent of 400 to 2500 g / mol.   The heat resistance according to any one of claims 1 to 6, further comprising an epoxy resin as the thermosetting resin and further containing a curing accelerator and / or a curing agent of the epoxy resin. Resin composition.   An adhesive film comprising the heat-resistant resin composition according to any one of claims 1 to 7.   A cured resin obtained by thermosetting the heat-resistant resin composition according to any one of claims 1 to 7.