JP2005349682A - Resin sheet structure and multi-layer wiring board using it - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a resin sheet structure which indicates fluidity when heated/pressurized, is excellent in mechanical properties, can be used as a heat resistant material, and is easy in handling and a multi-layer wiring board produced by using the structure. <P>SOLUTION: In the resin sheet structure, a resin composition layer which contains a polyamic acid (a) of the reaction product of a dicarboxylic acid anhydride (MA), a tetracarboxylic acid dianhydride (DA), and a diamine having a mole ratio MA/DA of 0.001-0.15, a mole ratio A/B of the total acid anhydride groups (A) of MA and DA to the amino groups (B) of the diamine of 0.9-1.1, an imidation ratio of 10% or below, and a reduced viscosity of 0.5-2.0 dl/g measured at 30°C as a N-methyl-2-pyrolidone solution of 0.5 g/dl concentration and a low molecular weight compound (b) 100-250°C in boiling point and in which 60-90 pts. mass of the component (a) and 10-40 pts. mass of the component (b) are contained per 100 pts. mass of the sum of the components (a) and (b) is formed on a film. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a resin sheet structure that exhibits fluidity when heated and pressurized, can be used as a heat-resistant material, and is easy to handle during lamination, and a method for producing a multilayer wiring board using the resin sheet structure.

  In recent years, electronic devices have been remarkably reduced in size and weight, and on the other hand, higher functionality has been achieved. In order to meet such demands, electronic circuit boards on which semiconductor elements are mounted are required to have a higher density of electrical wiring, and the routing of wiring continues to be complicated. In addition, in order to pass higher-speed electrical signals, the wiring length of electrical wiring is required to be further shortened, and accordingly, a semiconductor element having a small thermal expansion coefficient is mounted closer to the electronic circuit board than before. It has become necessary. In such a situation, unprecedented and large stress is applied to the resin used as the interlayer insulating layer of the electronic circuit board, and the occurrence of cracks in the resin is a big problem.

  Conventionally, an epoxy resin is used as an interlayer insulating resin for such a circuit board. Epoxy resins are widely used for electronic materials due to their high fluidity and easy handling, but their thermal expansion coefficient is not small, and because of thermosetting resins, mechanical properties such as tensile strength and elongation are not sufficient. Absent. As a method of lowering the thermal expansion coefficient, mixing of filler components having a low thermal expansion coefficient such as silica is used as a conventional means, but in such a method, the tensile strength and elongation properties are adversely affected and the material becomes brittle. It was not enough to solve the crack problem.

  On the other hand, attempts have been made in recent years to use a thermoplastic resin such as polyetheretherketone or liquid crystal polymer for an interlayer insulating film of an electronic circuit board. These generally have good mechanical properties. As one of such resins, a thermoplastic polyimide sheet has been proposed. In general, polyimide has been widely used as a substrate for an electronic circuit or an interlayer insulating resin layer as a material having a high glass transition temperature / high chemical resistance / excellent mechanical properties / excellent electrical characteristics. However, if polyimide is to be given thermoplasticity for bonding at a temperature suitable for electronic circuit boards, the glass transition temperature of polyimide must be significantly reduced, and another characteristic of polyimide is the low linear thermal expansion coefficient. Will be damaged. Furthermore, there is a method of forming an insulating layer by coating a solvent-soluble polyimide. However, when trying to impart solvent solubility to the polyimide, for example, it has a high affinity for a compound or solvent having a highly flexible structure. A compound having a structure was introduced into the molecular chain, and as a result, the original performance of polyimide was often impaired, such as a decrease in heat resistance, chemical resistance and mechanical properties.

  As a method of using polyimide, there is a method of using polyamic acid which is a polyimide precursor at the time of processing and then converting to polyimide by heat treatment. When this method is used, since it is soluble in a solvent in the state of polyamic acid, it is easy to process, and it is possible to select a molecular structure that does not have problems of heat resistance and chemical resistance. As such material, polyamic acid varnish dissolved in a solvent has been known for a long time, but in the varnish state, the viscosity stability due to moisture absorption is poor, so the varnish must be refrigerated or frozen when not in use. In addition, it was difficult to control the film thickness during coating, and a large amount of solvent had to be volatilized on the user side, which was complicated.

In order to overcome the above problem, a technique for drying and forming a polyamic acid varnish solution as a self-supporting film has been disclosed (see Patent Document 1). However, since polyamic acid has high polarity, it has high hygroscopicity even in a sheet state, and there is a problem that storage stability is lacking as it is.
On the other hand, a technique using a polyamic acid film formed on a release film is disclosed (see Patent Document 2). However, in the disclosed technology, the imidation ratio of the polyamic acid is too high to ensure sufficient fluidity to form an interlayer insulating layer by pressurization, and the reduced viscosity of the polyamic acid polymer is not practical. If it is too high, the fluidity is further impaired. In addition, there is no description about the mechanical properties required for use as an interlayer film, and there is a problem that sufficient mechanical properties cannot be obtained if the reduced viscosity is lowered too much in order to avoid the above-described problem of fluidity deterioration. No solution was shown for them.
Japanese Patent No. 2672906 JP-A-4-226544

  The present invention has fluidity when pressurized at a temperature that can be used for an electronic circuit board without impairing the high glass transition temperature, high chemical resistance, and excellent mechanical properties inherent in the polyimide. An object of the present invention is to provide a resin composition having good viscosity stability during production and excellent stability such as moisture absorption during storage, and a method for producing a multilayer wiring board using the same It is.

  As a result of intensive research in order to solve the above problems, the present inventor has a specific reduced viscosity and is imidized at a specific ratio or less, and is mixed with the polyamic acid described above to have a specific It has been found that a resin sheet structure in which a resin composition characterized by containing a low-molecular compound having a boiling point is formed on a release film can meet the purpose, and the present invention is made based on this finding. It came to.

That is, the present invention is as follows.
(1) a) a polyamic acid comprising a reaction product of a dicarboxylic acid anhydride (hereinafter abbreviated as MA), a tetracarboxylic dianhydride (hereinafter abbreviated as DA), and a diamine, the mole of DA and MA The ratio MA / DA is 0.001 to 0.15, and the molar ratio A of the sum of acid anhydride groups (hereinafter abbreviated as A) of MA and DA and the amino groups (hereinafter abbreviated as B) of diamine. / B is 0.9 to 1.1, the imidization ratio is 10% or less, and the reduced viscosity measured at 30 ° C. as an N-methyl-2-pyrrolidone solution having a concentration of 0.5 g / dl is 0. A polyamic acid in the range of 0.5 to 2.0 dl / g, and b) a low molecular compound having a boiling point of 100 ° C. or higher and 250 ° C. or lower, based on 100 parts by mass of the sum of the components a) and b), a) component is 60 to 90 parts by mass, and b) component is Resin sheet structure resin composition layer is 0 to 40 parts by weight is formed on the film.
(2) A method for producing a multilayer wiring board in which a film is peeled off from the resin sheet structure of (1) and sequentially laminated on a substrate, a low molecular compound is removed after the lamination, and a wiring layer is further formed.

  Since the resin sheet structure of the present invention has a structure formed on a film, it is difficult to absorb moisture, has excellent stability during storage and use in the manufacturing process of an electronic circuit board, and is an electronic circuit board because it is in the form of a sheet. It is excellent in handling in the manufacturing process, and further has a specific reduced viscosity and an imidization ratio of a specific ratio or less and contains a specific ratio of low molecular weight compounds. Therefore, it is necessary for application to the electronic circuit board manufacturing process. While having fluidity under heating and pressing conditions, an interlayer insulating resin layer having sufficient heat resistance, chemical resistance, and mechanical properties can be obtained after imidization proceeds after lamination. Furthermore, since the viscosity stability of the resin is high, it can be handled stably during the manufacture of the sheet structure.

Hereinafter, the present invention will be specifically described.
The resin sheet structure of the present invention comprises a resin composition layer and a film. The polyamic acid which is the component a) in the resin composition is obtained by reacting a dicarboxylic anhydride, a tetracarboxylic dianhydride and a diamine. Examples of the dicarboxylic acid anhydride include phthalic anhydride, benzophenone dicarboxylic acid anhydride, naphthalene dicarboxylic acid anhydride, anthracene dicarboxylic acid anhydride, maleic anhydride, succinic anhydride, and the like. Examples of tetracarboxylic dianhydride include pyromellitic dianhydride, biphenyltetracarboxylic dianhydride, benzophenone tetracarboxylic dianhydride, oxydiphthalic dianhydride, and the like. Examples of the diamine include phenylenediamine, diaminodiphenylmethane, diaminodiphenylsulfone, diaminodiphenyl ether, and 2,2-bis [4- (4-aminophenoxy) phenyl] propane.

  Preferred tetracarboxylic dianhydrides for use in the present invention are pyromellitic dianhydride, benzophenone-3,4,3 ′, 4′-tetracarboxylic dianhydride and biphenyl-3,4,3 ′, 4 ′. -Tetracarboxylic dianhydrides, preferred diamines for this invention are 4,4'-diaminodiphenyl ether and 2,2-bis [4- (4-aminophenoxy) phenyl] propane. Furthermore, each of dicarboxylic acid anhydride, tetracarboxylic dianhydride, and diamine can be used singly or in combination of two or more.

  The polyamic acid obtained by reacting these raw materials has a molar ratio A / B of the total acid anhydride groups of the dicarboxylic anhydride and tetracarboxylic dianhydride to the amino groups of the diamine of 0.9 to 1. .1 is preferable. From the viewpoint of mechanical properties, A / B is preferably 0.9 or more and 1.1 or less. The molar ratio MA / DA between DA and MA is preferably 0.001 to 0.15. MA / DA is preferably 0.001 or more from the viewpoint of fluidity during heating and pressurization, and MA / DA is preferably 0.15 or less from the viewpoint of mechanical properties. MA / DA is more preferably 0.005 to 0.10, and most preferably 0.01 to 0.06.

  These polyamic acids preferably have a reduced viscosity in the range of 0.5 to 2.0 dl / g measured at 30 ° C. as an N-methyl-2-pyrrolidone solution having a concentration of 0.5 g / dl. The reduced viscosity of the polyamic acid is preferably 2.0 dl / g or less from the viewpoint of fluidity during heating and pressurization, and the reduced viscosity is preferably 0.5 dl / g or less from the viewpoint of mechanical properties. A more preferable reduced viscosity is 0.8 to 2.0 dl / g, and still more preferably 1.1 to 1.5 dl / g.

  The reduced viscosity in the present invention is determined by N after the resin composition is peeled off from the film after the resin sheet structure is prepared and the polyamic acid mass is calculated using a thermobalance, and then the polyamic acid concentration is 0.5 g / dl. -Methyl-2-pyrrolidone solution is prepared and measured using a Ubbelohde viscometer tube of viscometer number 1 manufactured by Shibata Kagaku Co., Ltd. in a constant temperature water bath at a temperature of 30 ° C ± 1 ° C. The 0.5 g / dl N-methyl-2-pyrrolidone solution contains a low-molecular compound, but since it is a dilute solution of the N-methyl-2-pyrrolidone solution, the reduced viscosity is hardly affected.

  The mass of polyamic acid in the resin composition is determined by a thermobalance method. The resin composition is peeled from the prepared resin sheet, 10 mg of the resin composition is measured with a thermobalance up to 700 ° C. under a nitrogen stream at a temperature rising rate of 10 ° C./min, and the remaining mass at 400 ° C. is defined as the polyimide mass. The amount of water generated during imide ring formation was calculated based on the imidation ratio of the polyamic acid before heating, assuming that 1 mol of water was generated from 1 mol of the amide group in the resin composition, and the amount of water was calculated based on the previous polyimide mass. To the mass of the polyamic acid.

  The polyamic acid of the present invention can be polymerized from a solution in which diamine, dicarboxylic acid anhydride and tetracarboxylic dianhydride are added to a solvent. In this case, the polyamic acid concentration in the solution is preferably 10% by mass to 30% by mass. From the viewpoint that it is necessary to volatilize a large amount of solvent when preparing the resin sheet structure, the polyamic acid concentration in the solution is preferably 10% by mass or more. From the viewpoint of molding processability and storage stability, the polyamic acid concentration in the solution is preferably 30% by mass or less.

  These polyamic acids preferably have an imidization ratio of the amic acid moiety of 10% or less. In a resin composition composed of polyamic acid that has been imidized in excess of 10%, cracks may occur in the process of removing low molecular weight compounds after lamination, or it may not flow sufficiently during heating and pressurization in the lamination process. .

In the present invention, the imidization ratio of the polyamic acid is determined by the IR method as follows. The measuring instrument used is Centaurus manufactured by Thermo Nicolet Corporation, and measurement is performed by the ATR method using a Ge crystal. Journal of Polymer Science: Part A: Polymer Chemistry, Vol. 27, 711-724 (1989), the imidation rate is determined from the ratio of the peak based on the imide ring formation in the vicinity of 1380 cm ⁻¹ to the peak based on the benzene ring in the vicinity of 1500 cm ⁻¹ . That is, draw a baseline as appropriate so as to connect the valleys of the peaks before and after those peaks, and the height from the intersection of the line drawn from each peak to the baseline to the peak to the peak is the absorbance. As defined, the absorbance of 1380 cm ⁻¹ of the resin composition used in the resin sheet structure of the present invention is B1, and the absorbance of 1500 cm ⁻¹ is B2. On the other hand, when the resin sheet structure of the present invention is heat-treated at 300 ° C. for 60 minutes in a nitrogen atmosphere, the absorbance at 1380 cm ⁻¹ of the resin composition is A1, and the absorbance at 1500 cm ⁻¹ is A2. The imidization ratio C is calculated by an equation of ((B1 / B2) / (A1 / A2)) × 100 (%), with 100 at 60 ° C. for 60 minutes. When the absorption at 1380 cm ⁻¹ overlaps with the absorption of the low molecular compound, the absorption at 1720 or 1780 cm ⁻¹ can be used.

  The low molecular compound having a boiling point of 100 ° C. or higher and 250 ° C. or lower, which is the component b) in the resin sheet structure of the present invention, is preferably an organic solvent mixed with the polyamic acid. Examples include γ-butyrolactone, γ-valerolactone, N-methyl-2-pyrrolidone, N, N-dimethylformamide, N, N-dimethylacetamide, dimethyl sulfoxide, 1,3-dioxane, 1,4-dioxane, cyclo Examples include pentanone, cyclohexanone, diethylene glycol dimethyl ether, and tetramethylurea. Preferred low molecular compounds used in the present invention are γ-butyrolactone, N, N-dimethylformamide and N-methyl-2-pyrrolidone. These can be used alone or in admixture of two or more. In addition, for the purpose of improving sheet formability, propylene glycol monomethyl ether acetate, ethyl lactate, anisole, sulfolane, xylene, toluene, mesitylene and the like may be added.

  In the resin composition used in the present invention, it is preferable that the polyamic acid is 60 to 90 parts by mass and the low molecular compound is 10 to 40 parts by mass, based on 100 parts by mass of the polyamic acid and the low molecular compound. . The low molecular compound is preferably 10 parts by mass or more from the viewpoint of fluidity during heating and pressurization, and the low molecular compound is preferably 40 parts by mass or less from the viewpoint of sheet strength and handleability due to stickiness of the sheet. In addition, the ratio of the low molecular compound in the resin composition used by this invention shall be calculated | required by the measurement by a thermobalance method. The resin composition was peeled from the prepared resin sheet, and 10 mg of the resin composition was measured with a thermobalance in a nitrogen stream from room temperature to 700 ° C. at a heating rate of 10 ° C./min. The remaining mass is the polyimide mass, and the remaining amount scattered by heating is the volatile content up to 400 ° C. The amount of water generated during imide ring formation is calculated on the basis of the imidization ratio of the polyamic acid before heating, assuming that 1 mol of water is generated from 1 mol of amide groups in the resin composition, and the amount of water is calculated from the previous volatile matter. Except for the mass of the low molecular weight compound.

  Additives may be added to the resin composition used in the present invention depending on the application. Examples of the additive include a dehydrating agent, an imidization catalyst, a filler such as silica, a thermosetting resin such as an epoxy resin, a thermoplastic resin such as polyamide, a monofunctional or polyfunctional monomer, and an organic peroxide. Examples thereof include surface modifiers such as reaction catalysts and silane coupling agents.

  In the resin sheet structure of the present invention, the resin composition layer is formed on the film, so that the resin composition layer can be fused and pressure-bonded during storage or use, moisture absorption of the resin composition layer, and the resin composition layer. It is possible to prevent adhesion of dust and the like, and to facilitate handling of the resin composition layer during lamination. The film is not particularly limited as long as it has no problem when the resin composition layer is formed thereon and can be peeled off. Polyolefin such as polyethylene and polypropylene, polyester such as polyethylene terephthalate, polycarbonate , Polymer films such as polyimide, and metal foil. These thicknesses are not particularly limited.

  Moreover, as a film used by this invention, a support base film with a release layer can be used according to a use. Examples of the supporting base film include the polymer films described above. As the release layer, a known and commonly used silicone-based or non-silicone-based release agent can be used in accordance with the characteristics of the resin varnish, and the thickness is generally 0.1 to 3 μm.

  In the present invention, a method of forming a resin composition layer on a film includes a varnish obtained by dissolving the resin composition in a solvent on a film (hereinafter also referred to as a resin varnish), a rotary coater, a knife coater, a doctor blade, It can be obtained by applying the film by a known coating means such as a flow coater to a uniform thickness of 1 to 600 μm from the upper surface of the film and then heating as described later. In addition, a resin composition layer is formed on the film, and the resin composition layers of the same composition or different compositions formed on other films are aligned with the resin surface, and the film is peeled between them as necessary. A thick resin composition sheet can be obtained by inserting a predetermined number of the resin composition layers and simultaneously heating and pressure bonding.

In the present invention, the conditions for heating the resin varnish to form the resin composition layer on the film are usually 60 to 130 ° C. and 5 to 30 minutes. There is no particular limitation as long as the ratio of component a) to component b) and the imidization ratio are in the above ranges.
As thickness after heat forming of a resin composition layer, 5-80 micrometers is preferable. 80 μm or less is preferable from the viewpoint of causing stress due to shrinkage accompanying the heat treatment to exceed the supporting force of the film and causing curling during drying. Moreover, since the resin composition layer is thick, the evaporation rate of the solvent in the resin varnish is slow and the productivity is reduced. On the other hand, 5 μm or more is preferable from the viewpoint of mechanical properties.

The resin sheet structure of the present invention consisting of a resin composition layer and a film is stored as it is, or a protective film is further layered on the other surface of the resin composition layer and wound into a roll.
The method for producing a multilayer wiring board of the present invention comprises the step of bonding the resin sheet structure of the present invention to the conductor-forming substrate on the resin composition layer side, and further adding a low molecular compound of component b) in the resin composition layer. It is carried out by removing and simultaneously with or subsequently proceeding with imidization.
Conductor-forming substrates include resin substrates such as epoxy resins, thermosetting polyphenylene ether resins, and bismaleimide triazine resins, resin composite substrates reinforced with the resin and glass cloth, nonwoven fabric, and flexible substrates such as polyimide and liquid crystal polymers. The thing which formed the conductor with metal foil or plating is mentioned.

For the laminating process, a press machine and a roll laminator that can be normally used can be used. As the processing conditions, the resin sheet structure is superposed so that the resin layer faces the conductor forming substrate. 180 ° C., 0.5 to 9.8 MPa, 0.1 to 30 minutes, and in the case of a roll laminator, thermocompression bonding is performed under conditions such as 80 to 180 ° C., 0.1 to 4.9 MPa, 0.1 to 10 m / min. . In particular, as the temperature, it is preferable to carry out at a temperature that does not exceed + 50 ° C. than the heating temperature at the time of forming the resin composition layer because generation of volatiles is suppressed.
As a method for removing the low-molecular compound as component b), there are dry treatment and wet treatment. As the dry treatment, the film can be peeled and heat treatment can be performed. The heat treatment temperature can be selected according to the heat resistance of the substrate. The heat treatment time can be selected according to the application.

  For example, when laminated on a glass cloth reinforced epoxy resin cured substrate, the heat treatment temperature is 100 to 260 ° C., and the time is 10 to 500 minutes. When a sufficiently high temperature is selected as the heat treatment temperature, both the removal of low molecular weight compounds and the progress of imidization are achieved by the heat treatment. Moreover, as a wet process, after extracting a low molecular compound with water, alcohol, etc. according to the used low molecular compound, it can dry at low temperature. In this case, imidization can be advanced by performing a heat treatment subsequently.

The multilayer wiring board of the present invention in which the resin sheet of the present invention is laminated is subjected to a dry process such as laser processing or a wet process such as alkali etching to form a via with a conductor formation substrate, and then a method such as plating or sputtering. Further conductor formation is possible.
Next, the present invention will be described with reference to examples and reference examples.

The mechanical properties of a film obtained by imidizing the resin composition (hereinafter referred to as polyimide film) were evaluated by the elongation at break of the tensile strength / elongation curve. A film having a thickness of 10 μm prepared by heat treatment at 300 ° C. for 60 minutes under nitrogen was prepared and measured under the conditions of a sample width of 3 mm and a pulling speed of 40 mm / min.
The fluidity of the resin composition layer was determined by cutting the resin composition layer formed on the polyester film into a 10 cm square sheet and pressing it at a pressure of 2.9 MPa and 170 ° C. for 10 minutes, and then flowing out of the sheet. Was evaluated in terms of mass%. From the viewpoint of the resin composition exhibiting sufficient fluidity, the fluidity is preferably 5.0% by mass or more.

[Example 1]
A silica gel drying tube for absorbing water was attached to a 500 ml glass separable three-necked flask equipped with a stainless steel vertical stirrer. In this flask, 347.9 g of N-methyl-2-pyrrolidone (dehydrated) (hereinafter abbreviated as NMP) manufactured by Wako Pure Chemical Industries, Ltd., 4,4′-diaminodiphenyl ether (hereinafter abbreviated as ODA) manufactured by Wakayama Seika Kogyo Co., Ltd. After adding 27.5 g at room temperature, stirring and dissolving, the flask was cooled with ice water. When the temperature of the liquid in the flask reached 5 ° C., 0.5 g of phthalic anhydride (hereinafter abbreviated as PA) manufactured by Wako Pure Chemical Industries, Ltd. was added and stirred for 5 minutes. 4,4′-benzophenonetetracarboxylic dianhydride (hereinafter abbreviated as BTDA) was gradually added to the flask and stirred for 8 hours while cooling with ice water (A / B = 1.0, MA / DA). = 0.026). The reduced viscosity of the polyamic acid after completion of the reaction was 1.27 dl / g.

The elongation at break of the polyimide film obtained using this resin varnish was 49%.
The resin varnish was applied on a polyester film held on a smooth plate kept at 80 ° C., allowed to stand for 30 minutes, and then dried at 100 ° C. for 30 minutes in an air circulation type drying furnace to obtain a resin sheet structure. . The thickness of the resin composition layer after drying was 40 μm. As a result of analyzing the composition of this resin composition layer, it was 75.5 parts by mass of polyamic acid and 24.5 parts by mass of NMP having an imidization rate of 3% and a reduced viscosity of 1.08 dl / g.
The fluidity of this resin composition layer was 8.5% by mass, which was good fluidity.
The temperature rise rate of the resin composition peeled from the polyester film was 10 ° C./min, the 5% weight loss temperature based on the mass at 400 ° C. using a thermobalance under nitrogen was 571 ° C., and the heat resistance of the produced polyimide resin The property was good.

This resin sheet structure was vacuum-pressed at 90 ° C., 10 minutes, 4.9 MPa on a 5 cm square FR-4 substrate patterned with the resin composition layer side facing the substrate, and then the polyester film was peeled off, Although heat treatment was performed at 200 ° C. for 90 minutes in an air circulation type drying furnace, the resin composition was filled following the irregularities on the substrate surface, and defects such as fine cracks and voids were not seen on the substrate surface. It was.
The reduced viscosity of the polyamic acid after storing this resin varnish at room temperature for 5 days was 1.27 dl / g.

[Example 2]
A silica gel drying tube for absorbing water was attached to a 300-ml glass separable three-necked flask equipped with a stainless steel vertical stirrer. NMP256.3g and ODA13.5g were added to this flask at room temperature, and after stirring and dissolving, the flask was cooled with ice water. When the temperature of the liquid in the flask reached 5 ° C., 0.3 g of PA was added and after stirring for 5 minutes, 21.4 g of BTDA was gradually added to the flask and stirred for 8 hours while cooling with ice water (A / B = 1. 0, MA / DA = 0.026). The reduced viscosity of the polyamic acid after completion of the reaction was 0.85 dl / g.

The elongation at break of the polyimide film obtained using this resin varnish was 35%.
This resin varnish was spread on a polyester film held on a smooth plate kept at 80 ° C., allowed to stand for 30 minutes, and then dried at 100 ° C. for 30 minutes in an air circulation type drying furnace to obtain a resin sheet structure. . The thickness of the resin composition layer after drying was 40 μm. As a result of analyzing the composition of this resin composition layer, they were 74.0 parts by mass of polyamic acid and 26.0 parts by mass of NMP having an imidization rate of 4% and a reduced viscosity of 0.73 dl / g.
The fluidity of this resin composition layer was 10.0% by mass, which was good fluidity.
The temperature rise rate of the resin composition peeled from the polyester film was 10 ° C./min, the 5% weight loss temperature based on the mass at 400 ° C. using a thermobalance under nitrogen was 571 ° C., and the heat resistance of the produced polyimide resin The property was good.

This resin sheet structure was pressed at 130 ° C. for 2 minutes and 4.9 MPa on a patterned 5 cm square FR-4 substrate with the resin composition layer side facing the substrate, and then the polyester film was peeled off. Although heat treatment was performed at 200 ° C. for 90 minutes in an air circulation type drying furnace, the resin composition was filled following the irregularities on the substrate surface, and defects such as fine cracks and voids were not seen on the substrate surface. It was.
The reduced viscosity of the polyamic acid after storing this resin varnish at room temperature for 5 days was 0.85 dl / g.

[Example 3]
A silica gel drying tube for absorbing water was attached to a 300-ml glass separable three-necked flask equipped with a stainless steel vertical stirrer. NMP208.8g, Wakayama Seika Kogyo Co., Ltd. 2,2-bis [4- (4-aminophenoxy) phenyl] propane (hereinafter abbreviated as BAPP) 33.8g was added to this flask at room temperature and stirred and dissolved. Later, the flask was cooled with ice water. When the temperature of the liquid in the flask reached 5 ° C., 0.3 g of PA was added, and after 5 minutes, 26.2 g of BTDA was gradually added to the flask, stirred for 7 hours while cooling with ice water, and further at room temperature. The mixture was stirred for 1 hour (A / B = 1.0, MA / DA = 0.026). The reduced viscosity of the polyamic acid after completion of the reaction was 1.59 dl / g.

The elongation at break of the polyimide film obtained using this resin varnish was 29%.
This resin varnish was spread on a polyester film held on a smooth plate kept at 80 ° C., allowed to stand for 30 minutes, and then dried at 100 ° C. for 30 minutes in an air circulation type drying furnace to obtain a resin sheet structure. . The thickness of the resin composition layer after drying was 40 μm. As a result of analyzing the composition of this resin composition layer, it was 30.5 parts by mass of polyamic acid and 29.5 parts by mass of NMP having an imidization rate of 5% and a reduced viscosity of 1.34 dl / g.
The fluidity of this resin composition layer was 14.6% by mass, which was good fluidity.
The resin sheet structure was pressed on a 0.8 cm thick 10 cm square FR-5 substrate with the resin composition layer side facing the substrate at 130 ° C. for 2 minutes at 2.9 MPa, and then the polyester film was peeled off. Although heat treatment was performed at 200 ° C. for 90 minutes in an air circulation type drying furnace, no defects such as fine cracks and voids were found on the substrate surface.

  The reduced viscosity of the polyamic acid after storing this resin varnish at room temperature for 5 days was 1.59 dl / g.

[Example 4]
A silica gel drying tube for absorbing water was attached to a 300-ml glass separable three-necked flask equipped with a stainless steel vertical stirrer. NMP208.8g and BAPP33.8g were added to this flask at room temperature, and after stirring and dissolving, the flask was cooled with ice water. When the temperature of the liquid in the flask reached 5 ° C., 0.3 g of PA was added. After 5 minutes, 17.7 g of pyromellitic dianhydride (hereinafter abbreviated as PMDA) manufactured by Daicel Chemical Industries, Ltd. was gradually added to the flask. The mixture was stirred for 7 hours while cooling with ice water, and further stirred at room temperature for 1 hour (A / B = 1.0, MA / DA = 0.026). The reduced viscosity of the polyamic acid after the completion of the reaction was 1.71 dl / g.

The elongation at break of the polyimide film obtained using this resin varnish was 69%.
The resin varnish was spread on a polyester film held on a smooth plate kept at 80 ° C., allowed to stand for 30 minutes, and then dried at 100 ° C. for 30 minutes in an air circulation type drying furnace to obtain a resin sheet structure. . The thickness of the resin composition layer after drying was 40 μm. As a result of analyzing the composition of this resin composition layer, they were 71.5 parts by mass of polyamic acid and 28.5 parts by mass of NMP having an imidization rate of 5% and a reduced viscosity of 1.46 dl / g.
The fluidity of this resin composition layer was 7.6% by mass, which was good fluidity.

The resin sheet structure was pressed on a 0.8 cm thick 10 cm square FR-5 substrate with the resin composition layer side facing the substrate at 130 ° C. for 2 minutes at 2.9 MPa, and then the polyester film was peeled off. Although heat treatment was performed at 200 ° C. for 90 minutes in an air circulation type drying furnace, no defects such as fine cracks and voids were found on the substrate surface.
The reduced viscosity of the polyamic acid after storing this resin varnish at room temperature for 5 days was 1.71 dl / g.

[Example 5]
A silica gel drying tube for absorbing water was attached to a 500 ml glass separable three-necked flask equipped with a stainless steel vertical stirrer. After adding NMP347.9g and ODA27.5g to this flask at room temperature, stirring and melt | dissolving, the flask was cooled with ice water. When the temperature of the liquid in the flask reached 5 ° C., 0.5 g of PA was added, and after another 5 minutes, biphenyl-3,4,3 ′, 4′-tetracarboxylic dianhydride (hereinafter abbreviated as BPDA) 39 .9 g was gradually added to the flask, stirred for 7 hours while cooling with ice water, and further stirred for 1 hour at room temperature (A / B = 1.0, MA / DA = 0.026). The reduced viscosity of the resin after completion of the reaction was 1.23 dl / g.
The elongation at break of the polyimide film obtained using this resin varnish was 103%.

This resin varnish is spread on a polyester film held on a smooth plate kept at 80 ° C., left for 30 minutes, and then dried at 100 ° C. for 30 minutes in an air circulation type drying furnace to obtain a resin sheet structure. It was. The thickness of the resin composition layer after drying was 40 μm. As a result of analyzing the composition of this resin composition layer, they were 73.5 parts by mass of polyamic acid and 26.5 parts by mass of NMP having an imidization ratio of 5% and a reduced viscosity of 1.05 dl / g.
The fluidity of this resin composition layer was 8.5% by mass, which was good fluidity.

The resin sheet structure was pressed on a 0.8 cm thick 10 cm square FR-5 substrate with the resin composition layer side facing the substrate at 130 ° C. for 2 minutes at 2.9 MPa, and then the polyester film was peeled off. Although heat treatment was performed at 200 ° C. for 90 minutes in an air circulation type drying furnace, no defects such as fine cracks and voids were found on the substrate surface.
The reduced viscosity of the polyamic acid after storing this resin varnish at room temperature for 5 days was 1.23 dl / g.

[Example 6]
A silica gel drying tube for absorbing water was attached to a 300-ml glass separable three-necked flask equipped with a stainless steel vertical stirrer. NMP93.2g and ODA16.5g were added to this flask at room temperature, and after stirring and dissolving, the flask was cooled with ice water. When the temperature of the liquid in the flask reached 5 ° C., 0.16 g of PA was added, and after stirring for 5 minutes, 26.3 g of BTDA was gradually added to the flask and stirred for 8 hours while cooling with ice water. When the viscosity increased during the reaction, 153.4 g of NMP was added (A / B = 1.0, MA / DA = 0.013). The reduced viscosity of the polyamic acid after completion of the reaction was 1.83 dl / g.

The elongation at break of the polyimide film obtained using this resin varnish was 63%.
The resin varnish was applied on a polyester film held on a smooth plate kept at 80 ° C., allowed to stand for 30 minutes, and then dried at 100 ° C. for 30 minutes in an air circulation type drying furnace to obtain a resin sheet structure. . The thickness of the resin composition layer after drying was 40 μm. As a result of analyzing the composition of this resin composition layer, they were 74.5 parts by mass of polyamic acid and 25.5 parts by mass of NMP having an imidization rate of 3% and a reduced viscosity of 1.60 dl / g.
The fluidity of this resin composition layer was 7.5% by mass, which was good fluidity.
The temperature rise rate of the resin composition peeled from the polyester film was 10 ° C./min, the 5% weight loss temperature based on the mass at 400 ° C. using a thermobalance under nitrogen was 570 ° C., and the heat resistance of the produced polyimide resin The property was good.

This resin sheet structure was vacuum-pressed at 90 ° C. for 10 minutes and 4.9 MPa on a patterned 5 cm square FR-4 substrate with the resin composition layer side facing the substrate, and then the polyester film was peeled off. Although the heat treatment was performed at 200 ° C. for 90 minutes in an air circulation type drying furnace, the resin composition was filled following the unevenness of the substrate surface, and defects such as fine cracks and voids were found on the substrate surface. There wasn't.
The reduced viscosity of the polyamic acid after storing this resin varnish at room temperature for 5 days was 1.83 dl / g.

[Example 7]
A silica gel drying tube for absorbing water was attached to a 300-ml glass separable three-necked flask equipped with a stainless steel vertical stirrer. NMP208.4g and ODA16.5g were added to this flask at room temperature, and after stirring and dissolving, the flask was cooled with ice water. When the temperature of the liquid in the flask reached 5 ° C., 0.64 g of PA was added, and after stirring for 5 minutes, 25.8 g of BTDA was gradually added to the flask and stirred for 8 hours while cooling with ice water (A / B = 1. 0, MA / DA = 0.054). The reduced viscosity of the polyamic acid after completion of the reaction was 0.94 dl / g.

The elongation at break of the polyimide film obtained using this resin varnish was 58%.
The resin varnish was applied on a polyester film held on a smooth plate kept at 80 ° C., allowed to stand for 30 minutes, and then dried at 100 ° C. for 30 minutes in an air circulation type drying furnace to obtain a resin sheet structure. . The thickness of the resin composition layer after drying was 40 μm. As a result of analyzing the composition of this resin composition layer, they were 73.5 parts by mass of polyamic acid and 26.5 parts by mass of NMP having an imidization rate of 4% and a reduced viscosity of 0.77 dl / g.
The fluidity of this resin composition layer was 9.0% by mass, which was good fluidity.
The temperature rise rate of the resin composition peeled from the polyester film was 10 ° C./min, the 5% weight loss temperature based on the mass at 400 ° C. using a thermobalance under nitrogen was 571 ° C., and the heat resistance of the produced polyimide resin The property was good.

This resin sheet structure was vacuum-pressed at 90 ° C. for 10 minutes and 4.9 MPa on a patterned 5 cm square FR-4 substrate with the resin composition layer side facing the substrate, and then the polyester film was peeled off. Although the heat treatment was performed at 200 ° C. for 90 minutes in an air circulation type drying furnace, the resin composition was filled following the unevenness of the substrate surface, and defects such as fine cracks and voids were found on the substrate surface. There wasn't.
The reduced viscosity of the polyamic acid after storing this resin varnish at room temperature for 5 days was 0.94 dl / g.

[Comparative Example 1]
The surface of the resin sheet structure of Example 1 was covered with a fluororesin film, and after heat treatment at 130 ° C. for 10 minutes, the fluororesin film was peeled off and the composition of the resin composition layer was analyzed. It was 76.5 parts by mass of polyamic acid and 23.5 parts by mass of NMP containing water.
This resin sheet structure was pressed at 90 ° C. for 10 minutes at 4.9 MPa on a FR-5 substrate having a thickness of 10 mm square with the resin composition layer side facing the substrate, and then the polyester film was peeled off. Fine cracks were found on the surface of the substrate heat-treated at 200 ° C. for 90 minutes in an air circulation type drying furnace.

[Comparative Example 2]
The surface of the resin sheet structure of Example 1 was covered with a fluororesin film, and after heat treatment at 110 ° C. for 10 minutes, the fluororesin film was peeled off and the composition of the resin composition layer was analyzed. It was 75.5 parts by mass of polyamic acid and 24.5 parts by mass of NMP containing water.
The resin sheet structure was pressed at 90 ° C. for 10 minutes at 4.9 MPa on a FR-5 substrate having a thickness of 10 mm and a resin composition layer side facing the substrate, and then the polyester film was peeled off. Fine cracks were found on the surface of the substrate heat-treated at 200 ° C. for 90 minutes in an air circulation type drying furnace.

[Comparative Example 3]
A silica gel drying tube for absorbing water was attached to a 300-ml glass separable three-necked flask equipped with a stainless steel vertical stirrer. NMP180.6g and ODA20.1g were added to this flask at room temperature, and after stirring and dissolving, the flask was cooled with ice water. When the temperature of the liquid in the flask reached 5 ° C., 2.4 g of PA was added and stirred for 5 minutes, and then 29.7 g of BTDA was gradually added to the flask and stirred for 8 hours while cooling with ice water (A / B = 1). 0.0, MA / DA = 0.17). The reduced viscosity (30 ° C., polymer concentration 0.5 g / dl, NMP) of the polyamic acid after the reaction was 0.42 dl / g.
The elongation at break of the polyimide film obtained using this resin varnish was 8.8%.

[Comparative Example 4]
Dry nitrogen was passed through a 500 ml glass separable three-necked flask equipped with a stainless steel vertical stirrer. NMP400.0g and Wako Pure Chemical Industries p-phenylenediamine 20.94g were added to this flask at room temperature, and it stirred and melt | dissolved at 20 degreeC. While the temperature of the liquid in the flask was 20 ° C., 28.5 g of BPDA was gradually added to the flask, and 21.1 g of PMDA was gradually added. 20 minutes after adding PMDA, the temperature was raised to 30 ° C. and the mixture was stirred for 3 hours. Furthermore, it stirred at room temperature for 5 hours (A / B = 1.0, MA / DA = 0). The reduced viscosity (30 ° C., polymer concentration 0.5 g / dl, NMP) of the polyamic acid after the reaction was 3.10 dl / g.
After the resin varnish was stored at room temperature for 5 days, the reduced viscosity (30 ° C., polymer concentration 0.5 g / dl, NMP) of the polyamic acid was 1.97 dl / g, and the viscosity decreased.

[Comparative Example 5]
After adding 9.5 mass% 2-ethyl-4-methylimidazole with respect to the resin varnish of Example 1, and stirring for 30 minutes at room temperature, the resin sheet structure was obtained by the method similar to Example 1. FIG.
The imidation ratio of the polyamic acid of this resin sheet structure was 14%.
The fluidity of this resin composition layer was 0.4% by mass, and the fluidity was poor.

  The present invention has excellent moldability, mechanical properties, and heat resistance, is easy to handle, and is suitable as an insulating material for electronic circuit boards.

Claims (2)

  a) a polyamic acid comprising a reaction product of a dicarboxylic anhydride (hereinafter abbreviated as MA), a tetracarboxylic dianhydride (hereinafter abbreviated as DA) and a diamine, wherein the molar ratio of DA and MA is MA / DA is 0.001 to 0.15, and the molar ratio A / B of the total of acid anhydride groups (hereinafter abbreviated as A) possessed by MA and DA and the amino group (hereinafter abbreviated as B) possessed by diamine is 0.9 to 1.1, the imidization ratio is 10% or less, and the reduced viscosity measured at 30 ° C. as an N-methyl-2-pyrrolidone solution having a concentration of 0.5 g / dl is 0.5 to A) component containing polyamic acid in the range of 2.0 dl / g and b) a low molecular compound having a boiling point of 100 ° C. or higher and 250 ° C. or lower, based on 100 parts by mass of the sum of a) component and b) component Is 60 to 90 parts by mass and b) the component is 10 to 0 resin sheet structure resin composition layer is formed on the film is a parts by weight.   The method includes the steps of peeling the film from the resin sheet structure of claim 1 and laminating the substrate on which the wiring layer is formed, removing the low molecular weight compound after laminating, and further laminating the substrate to form the wiring layer. A method of manufacturing a multilayer wiring board characterized by the above.