JP2005314562A - Thermosetting resin composition and its application - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a thermosetting resin composition capable of suitably being used for producing a printed board, etc., and having superior adhesion, processability, heat resistance, and, furthermore, superior resin flowability and dielectric characteristic at a GHz zone, and to provide its representative application technology. <P>SOLUTION: This thermosetting resin composition comprises a polyimide resin component (A), an epoxy resin component (B) and a hardener component (C) for the epoxy resin. The each components described above are formulated so that the total mole of an epoxy group contained in the thermosetting resin composition and a hydroxyl group caused by its ring opening reaction is ≤0.2 mole/100 g. Furthermore, the epoxy resin component (B) comprises at least a low viscosity epoxy resin that has an ICI viscosity of ≤0.5 Pa s at 150°C. Thereby, many balanced and good characteristics such as adhesion are provided for the thermosetting resin composition and its hardened resin. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a thermosetting resin composition and use thereof, and particularly includes a polyimide resin component, an epoxy resin component, and an epoxy curing agent component, and is suitably used for manufacturing various printed wiring boards. The present invention relates to a typical use such as a thermosetting resin composition that can be used and a resin sheet, a laminate, a printed wiring board, and the like using the same.

  In order to improve the information processing capability in electronic devices, in recent years, electrical signals that transmit circuits on printed wiring boards used in electronic devices have been increased in speed and frequency. Therefore, it is desired to maintain the electrical reliability of the printed wiring board even when the electrical signal is increased in frequency, and to suppress the decrease in the transmission speed of the electrical signal in the circuit and the loss of the electrical signal. There are various types of printed wiring boards, and representative ones include flexible printed wiring boards, rigid printed wiring boards, multilayer flexible printed wiring boards, multilayer rigid wiring boards, build-up wiring boards, etc. it can.

  By the way, an insulating layer such as a protective film for protecting the wiring board or circuit or an interlayer insulating film for ensuring insulation between layers in the multilayer wiring board is usually provided on the printed wiring board. It is formed. Since the insulating layers such as the protective film and the interlayer insulating film are provided on the wiring board, in addition to the insulating properties, adhesiveness for bonding to the wiring board is also required.

  In particular, in the production of multilayer flexible printed wiring boards, build-up wiring boards, etc., when the interlayer insulating film is formed on a conductor circuit that has already been formed to produce a multilayered circuit board, the interlayer insulation The film and the insulating film on which the circuit is formed are bonded and fixed together, and at the same time, the material of the interlayer insulating film fills the space between the circuit wirings and the wiring is fixed. For this reason, the interlayer insulating film is required to have fluidity enough to fill the space between the circuit wirings together with excellent adhesion to the circuit, the substrate, and the like. Therefore, the insulating layers such as the protective film and the interlayer insulating film are formed using an adhesive material having adhesiveness and resin fluidity.

  Therefore, when an insulating layer is formed using the adhesive material, the adhesive material (insulating layer) has at least (1) a characteristic that does not adversely affect the transmission of an electric signal (especially in the GHz band), that is, a low dielectric characteristic. Furthermore, it is desirable to have (2) fluidity sufficient to embed circuit wiring together with excellent adhesiveness. Thereby, the printed wiring board for electronic devices which require a high-speed and high frequency electric signal can be provided.

  Here, conventionally, an epoxy adhesive material or a thermoplastic polyimide adhesive material is generally used as the adhesive material used for the wiring board. The above-mentioned epoxy-based adhesive material is excellent in workability such as bonding between adherends under low temperature and low pressure conditions and embedding between circuit wiring lines, and excellent adhesion to adherends. Yes. The thermoplastic polyimide-based adhesive material has excellent heat resistance such as low thermal expansion and high thermal decomposition temperature.

Further, various techniques using a resin composition containing an epoxy resin and a polyimide resin have been proposed as the adhesive material. Specifically, for example, Patent Documents 1 to 4 disclose an adhesive film containing a polyimide resin using a specific acid dianhydride and a thermosetting resin such as an epoxy resin.
JP 2002-12845 A (publication date: January 15, 2002) JP 7-228697 A (publication date: August 29, 1995) JP-A-8-27430 (Publication date: January 30, 1996) WO03 / 006553 Publication (International Publication Date: January 23, 2003)

  However, the above-mentioned conventional adhesive material has a problem that its various characteristics are still insufficient for using it for the purpose of manufacturing a wiring board corresponding to the high frequency of electric signals.

  Specifically, first, in the general epoxy adhesive material, the cured resin (epoxy resin) after curing has a dielectric constant of 4 or more in the GHz band and a dielectric loss tangent of 0.03 or more. Therefore, good dielectric properties cannot be obtained. In contrast, the thermoplastic polyimide-based adhesive material has a dielectric constant of 3.5 or less and a dielectric loss tangent of 0.02 or less in a cured resin (thermoplastic polyimide-based resin) after curing. Excellent dielectric properties. On the other hand, in order to adhere the adherends to each other using the thermoplastic polyimide adhesive material, it is necessary to adhere the adherends under high temperature and high pressure conditions, and the resin fluidity is not sufficient. .

  In addition, the adhesive films disclosed in Patent Documents 1 to 3 are all a mixture of a polyimide resin and an epoxy compound, can be bonded at a low temperature in a short time, and have high heat resistance at high temperatures. It is said that it is excellent. However, the composition of the constituent components of the adhesive film that greatly affects the dielectric properties and the fluidity for circuit embedding is not disclosed in any document. Moreover, only the die-bonding material is disclosed about the use, and the interlayer adhesive material for the printed wiring board is not described in any document. Therefore, no consideration is given to “resin fluidity and excellent dielectric properties” required for the use of printed wiring boards, and therefore such properties cannot be expected.

  Patent Document 4 discloses a resin composition containing a polyimide resin using a specific acid dianhydride and a thermosetting resin. However, it does not describe the composition of the constituent components of the adhesive film that greatly affects the dielectric properties and the fluidity for circuit embedding.

  Therefore, in order to improve the information processing capability of electronic equipment by increasing the frequency of electrical signals, the insulating layer has (i) adhesiveness, (ii) workability and handleability, (iii) heat resistance, (iv In addition to having sufficient resin fluidity, (v) a cured resin after curing is required to exhibit a low dielectric constant and a low dielectric loss tangent even in the GHz band and exhibit sufficient dielectric properties. Therefore, in order to form the said insulating layer, development of the adhesive material which makes the various characteristics of said (i)-(v) sufficient is anticipated.

  The present invention has been made to solve the above-mentioned conventional problems, and its purpose can be suitably used for the production of various printed wiring boards, etc., and is excellent in adhesiveness, workability, and heat resistance. Furthermore, it is providing the thermosetting resin composition excellent in the resin fluidity | liquidity and the dielectric characteristic in a GHz band, and its typical utilization technique.

  As a result of intensive studies in view of the above problems, the inventors of the present invention include a polyimide resin component, an epoxy resin component, and an epoxy curing agent component, which are included in the thermosetting resin composition. (I) a printed wiring board as an adhesive material and an insulating layer by controlling the total number of moles of epoxy groups and the number of moles of hydroxyl groups generated by the ring-opening reaction, and by setting the viscosity of the epoxy resin used to a certain value or less Adhesiveness to adherends such as (ii) Processability and handleability that enables adhesion at low temperatures, (iii) Excellent heat resistance regarding thermal expansion and thermal decomposition, and (iv) Embedding circuits In addition, the fluidity of the resin required for the resin is specifically improved, and (v) the dielectric constant and dielectric loss tangent of the GHz band in the cured resin after curing can be lowered, and the dielectric properties are also excellent. As a result, the present invention has been completed.

  That is, the thermosetting resin composition according to the present invention includes (A) a polyimide resin component, (B) an epoxy resin component, and (C) an epoxy curing agent component in order to solve the above problems. It is a resin composition, Comprising: As for each said component, the sum total of the mole number of the epoxy group contained in the said thermosetting resin composition and the hydroxyl group produced by the ring-opening reaction will be 0.2 mol / 100g or less. In addition, the (B) epoxy resin component contains at least a low-viscosity epoxy resin having an ICI viscosity at 150 ° C. of 0.5 Pa · s or less.

  In the thermosetting resin composition, the minimum melt viscosity is 10 Pa · s or more and 10,000 Pa · s or less under the condition that it is in a semi-cured state and the temperature is in the range of 60 ° C. or more and 200 ° C. or less. It is preferable to show.

  Moreover, in the said thermosetting resin composition, it is preferable that the dielectric loss tangent in GHz band after hardening will be 0.025 or less. Furthermore, in the said thermosetting resin composition, it is preferable that the tensile strength after hardening is 50 Mpa or more, and it is preferable that the tensile elongation rate after hardening is 3% or more.

  Furthermore, in the said thermosetting resin composition, it is preferable that the volume resistance in the normal temperature after hardening is 10E + 15 ohm * cm or more, and it is preferable that the volume resistance in 125 degreeC after hardening is 10E + 14 ohm * cm or more.

  In the said thermosetting resin composition, at least 1 type of polyimide resin contained in the said (A) polyimide resin component is general formula (1).

(Wherein, X ¹ is selected from the group consisting of —O—, —CO—, —O—X ² —O—, and —COO—X ² —OCO—, —C (CF ₃ ) ₂ —. A divalent group selected, and X ² represents a divalent organic group)
The (A-1) acid dianhydride component comprising at least one acid dianhydride having a structure represented by the formula (A-2) and the (A-2) diamine component comprising at least one diamine are reacted. It is preferable that it is obtained.

  In addition, the present invention includes a resin sheet comprising the thermosetting resin composition, a laminate comprising at least one resin layer formed using the thermosetting resin composition, and interlayer adhesion for printed wiring boards. The printed wiring board which uses a material and the said thermosetting resin composition is also contained.

  As described above, in the present invention, when blending each component, the number of moles of the epoxy group and the resulting hydroxyl group is defined, and the low viscosity epoxy resin defined by the ICI viscosity is used. Thereby, the thermosetting component in a thermosetting resin composition can be made into the conditions suitable for manufacture of various printed wiring boards. Therefore, (i) adhesiveness to adherends such as printed wiring boards, (ii) workability and handleability that enables adhesion at low temperature, (iii) heat resistance related to thermal expansion and thermal decomposition, (iv) circuit It is possible to provide a resin flowability necessary for embedding the resin and an excellent thermosetting resin composition. Moreover, in the cured resin obtained by curing the thermosetting resin composition, the dielectric constant and dielectric loss tangent in the GHz band can be made much lower than those of conventional resin compositions composed of polyimide resin and epoxy resin. Therefore, (v) a thermosetting resin composition having excellent dielectric properties can be provided.

  Therefore, the thermosetting resin composition according to the present invention realizes various properties such as excellent dielectric properties, fluidity, heat resistance, adhesiveness, and workability in a balanced manner as compared with conventional resin compositions. There is an effect that can be. In addition, since it is particularly excellent in dielectric properties, it is suitable for use in the manufacture of flexible printed wiring boards, build-up wiring boards, and laminates that require low relative permittivity and low dielectric loss tangent in the GHz band. There is also an effect that can be done.

  One embodiment of the present invention will be described in detail below, but the present invention is not limited to the following description.

In the present embodiment, the present invention is described in detail in the order of the outline of the thermosetting resin composition according to the present invention, each component of the thermosetting resin composition, and the use of the thermosetting resin composition. explain.
(I) Thermosetting resin composition according to the present invention <Total number of moles of hydroxyl groups generated by epoxy group and ring-opening reaction thereof>
The thermosetting resin composition according to the present invention includes at least (A) a polyimide resin component, (B) an epoxy resin component, and (C) an epoxy curing agent component. Ingredients may be included. Each component (essential component) of the above (A) to (C) includes at least one substance classified into each component.

  As a result of intensive studies to reduce the dielectric properties of the thermosetting resin composition after curing, in particular, the dielectric loss tangent, the present inventors have found that the epoxy groups contained in the thermosetting resin composition and the opening thereof. The thermosetting resin composition according to the present invention is cured by blending the above components so that the total number of moles of hydroxyl groups generated by the ring reaction (hereinafter simply referred to as the total number of moles of epoxy groups-hydroxyl groups) is reduced. It was found that the dielectric loss tangent of the cured resin (cured product) can be 0.025 or less. This is thought to be because the hydroxyl group produced by the reaction of the epoxy group affects the dielectric loss tangent, and reducing the number makes the influence of the polyimide resin, which originally has excellent dielectric properties, remarkable.

When the total number of moles of epoxy group-hydroxyl group is M _EH , M _EH can be calculated by the following formula (i). Incidentally, (A) polyimide amount of the resin component (unit: g) of the as W _A, (B) the amount of the epoxy resin component (unit: g) of was and W _B, (C) the amount of the epoxy curing agent component (unit: g) of the set to W _C, (B) an epoxy equivalent of the epoxy resin component (unit: g / eq) and E _B to. The unit of M _EH is mol / 100 g.

M _EH = {(W _B / E _B ) / (W _A + W _B + W _C )} × 100 (i)
However, when a hydroxyl group is included in the chemical structure of the (B) epoxy resin component, the amount of the hydroxyl group is added to the epoxy group of the (B) epoxy resin component to calculate the total number of moles of the epoxy group-hydroxyl group. To do.

  In the present invention, the total number of moles of the epoxy group-hydroxyl group needs to be 0.2 mol / 100 g or less. At this time, the dielectric loss tangent is 0.025 or less. It is preferable for the present invention that the dielectric loss tangent is as small as possible. Therefore, it is preferable that the total number of moles of epoxy group-hydroxyl group is as small as possible. Specifically, it is more preferably 0.18 mol / 100 g or less, and further preferably 0.15 mol / 100 g or less.

<Low viscosity epoxy resin specified by ICI viscosity>
In order to reduce the total number of moles of the epoxy group-hydroxyl group, the blending amount of the (B) epoxy resin component is simply reduced, and this makes it possible to reduce the dielectric loss tangent. However, it became clear by examination that if the blending amount of the (B) epoxy resin component is reduced, the resin fluidity, which is an advantage of the epoxy resin, is lowered.

  Therefore, as a result of further intensive studies, the inventor (B) epoxy resin component used in the present invention has an epoxy resin whose ICI viscosity at 150 ° C. of the epoxy resin is 0.5 Pa · s or less (for convenience of explanation, It has been found that the inclusion of at least one low-viscosity epoxy resin) has an effect of improving the resin fluidity.

  The ICI viscosity in the low-viscosity epoxy resin may be 0.5 Pa · s or less, but is preferably as low as possible for the present invention. Specifically, it is more preferably 0.3 Pa · s or less, and further preferably 0.1 Pa · s or less. When the ICI viscosity of the epoxy resin exceeds 0.5 Pa · s, the resin fluidity is lowered, and there may be a problem in embedding the wiring circuit.

  The ICI viscosity is a viscosity measured with an ICI cone plate viscometer. A cone plate type viscometer sandwiches a sample between a conical cone and a flat plate with a heater, and measures the viscosity of the sample from the torque generated by rotating the cone. The ICI viscosity thus measured can measure the absolute viscosity of a sample as a fluid, and is widely used for rheological analysis. In the present invention, by using at least the low-viscosity epoxy resin defined by the above ICI viscosity as the (B) epoxy resin component, that is, by evaluating the fluid properties of the (B) epoxy resin component by the ICI viscosity, It is possible to satisfactorily control the resin fluidity of the resulting thermosetting resin composition. In addition, the specific measuring method of ICI viscosity is not specifically limited, What is necessary is just to measure on well-known conditions using a well-known ICI cone plate viscometer.

<Composition 2: Thermosetting resin composition: Mixing ratio of components (A) to (C)>
In the thermosetting resin composition, as a method for improving the resin fluidity, there is a method of increasing the compounding amount of the epoxy resin component, but since the dielectric loss tangent tends to increase as described above, the present invention Not good for. Therefore, in order to moderately increase the dielectric loss tangent and improve the resin fluidity, (A) a polyimide resin component, (B) an epoxy resin component, and (C) an epoxy curing agent component are blended at an appropriate blending ratio. Is preferred. That is, in the present invention, a thermosetting resin composition having excellent dielectric loss tangent and resin fluidity is obtained by blending each component in a range where the total number of moles of epoxy groups-hydroxyl groups does not exceed 0.2 mol / 100 g. be able to. As a specific blending ratio satisfying these, each component of (A) polyimide resin component, (B) epoxy resin component, and (C) epoxy curing agent component is (A) / [(B) + by mass ratio. (C)] is preferably blended so as to be 0.4 or more and 2.0 or less, and more preferably 0.70 or more and 1.35 or less. Furthermore, it is preferable to mix | blend at 0.8 or more and 1.3 or less.

  The mass ratio is less than 0.4, that is, the total amount of (B) epoxy resin component and (C) epoxy hardener component contained in the thermosetting resin composition ((B) + (C)). However, if it becomes relatively larger than the content of the (A) polyimide resin component, (iii) heat resistance and (iv) resin fluidity are improved, but (v) dielectric properties cannot be made sufficient. That is, when the mass mixing ratio is less than 0.4, the fluidity of the thermosetting resin composition (for example, resin sheet) before curing increases, the minimum value of the melt viscosity decreases, and the circuit embedding property improves. . Moreover, the heat resistance represented by the elastic modulus, linear expansion coefficient, etc. at the time of high temperature of the cured resin after hardening becomes high. On the other hand, in the cured resin sheet, it is difficult to achieve a low relative dielectric constant and a low dielectric loss tangent (excellent dielectric characteristics) in the GHz (gigahertz) band.

  The excellent dielectric characteristics will be described more specifically. A cured resin can be obtained by heating the thermosetting resin composition at a temperature of 150 ° C. to 250 ° C. for 1 to 5 hours. In this cured resin, the dielectric constant is at a frequency in the GHz band. When it is 3.3 or less and the dielectric loss tangent is 0.025 or less, excellent dielectric characteristics are realized. If the dielectric constant and the dielectric loss tangent are within the above ranges, even when the thermosetting resin composition according to the present invention is used as a protective material or an interlayer insulating material for a printed wiring board, the electrical insulation of the printed wiring board. Therefore, it is possible to provide a highly reliable printed wiring board because it is possible to prevent the decrease in signal transmission speed and signal loss of the circuit on the printed wiring board.

  On the other hand, the mass mixing ratio exceeds 2.0, that is, the content of the (A) polyimide resin component contained in the thermosetting resin composition is (B) an epoxy resin component and (C) an epoxy. When it becomes relatively larger than the total blending amount ((B) + (C)) with the curing agent component, (v) the dielectric properties can be improved, but (i) adhesiveness, (ii) workability・ Handling and (iv) resin fluidity will decrease. That is, when the mass mixing ratio exceeds 2.0, the cured resin after curing can obtain excellent dielectric characteristics in the GHz band. However, in the thermosetting resin composition before curing, the adhesion between the thermosetting resin composition and the conductor or the printed wiring board, or the bonding between the thermosetting resin composition and the conductor or the printed wiring board is not possible. The workability is impaired, and in particular, the circuit embedding property is greatly impaired due to a decrease in resin fluidity.

<Composition 2: Thermosetting resin composition 2: Mixing ratio of components (B) and (C)>
In the thermosetting resin composition according to the present invention, it is more preferable to further define the mixing ratio of the components (B) and (C). The mixing ratio of these two components is defined by the molar ratio. The number of moles of the epoxy group of the epoxy resin contained in the (B) epoxy resin component is represented by the symbol (B) as in the case of the above mass, and the number of moles of active hydrogen contained in the (C) epoxy curing agent component. Is represented by the symbol (C), the molar mixing ratio (C) / (B) of these two components is preferably within a predetermined range.

  Specifically, the lower limit of the molar mixing ratio (C) / (B) is preferably 0.4 or more, and more preferably 0.7 or more. On the other hand, the upper limit of the molar mixing ratio (C) / (B) is preferably 2.0 or less, and more preferably 1.1 or less. Therefore, the preferable range of the molar mixing ratio is in the range of 0.4 to 2.0.

  As a result, (i) adhesion to adherends such as printed wiring boards and conductors, and (ii) workability and handling that enable adhesion at low temperatures for the resulting thermosetting resin composition and cured resin. (Iii) heat resistance related to thermal expansion and thermal decomposition, (iv) resin fluidity necessary for embedding a circuit, and (v) dielectric properties of cured resin. Various characteristics such as moisture resistance test resistance (PCT resistance) by soldering, solder heat resistance, and insulation can be made excellent, and the balance of these characteristics can be made good.

  If the molar mixing ratio is less than 0.4 or exceeds 2.0, (v) dielectric properties are adversely affected in the cured resin after curing. Moreover, also in the thermosetting resin composition before hardening, a glass transition temperature, a thermal expansion coefficient, and the elasticity modulus at the time of high temperature fall, and (iii) heat resistance is also impaired.

<Characteristics of thermosetting resin composition>
The thermosetting resin composition according to the present invention comprises the components (A) to (C) as essential components, and epoxy groups contained in the thermosetting resin composition and hydroxyl groups generated by the ring-opening reaction. 150 ° C. of at least one epoxy resin blended so that the total number of moles is 0.2 mol / 100 g or less and contained in the (B) epoxy resin component contained in the thermosetting resin composition ICI viscosity is 0.5 Pa · s or less. Although the specific characteristics in this thermosetting resin composition are not particularly limited, by defining the minimum value of the melt viscosity under the specific conditions (minimum melt viscosity), (iv) It can be made more preferable. Specifically, the minimum melt viscosity is in the range of 10 Pa · s or more and 10,000 Pa · s or less in the semi-cured state and the temperature is in the range of 60 ° C. or more and 200 ° C. or less. It is preferable.

  If the minimum melt viscosity under the above conditions exceeds 10,000 Pa · s, (iv) even if the resin fluidity becomes insufficient and bubbles remain between the circuits, or even if the layers can be laminated without bubbles, In other words, a circuit (pattern circuit) formed with a predetermined pattern is embossed, and a state in which the unevenness of the surface becomes large is likely to occur. That is, when the minimum melt viscosity exceeds the above upper limit, a situation unfavorable for subsequent processes such as circuit formation and multilayering tends to occur. Therefore, the surface irregularities are preferably as small as possible. Specifically, the ten-point average surface roughness Rz is preferably 10 μm or less, more preferably 5 μm or less, and even more preferably 1 μm or less.

  On the other hand, when the minimum melt viscosity is less than 10 Pa · s, a large amount of the thermosetting resin composition protrudes to the outside of the substrate during processing, and the amount of resin remaining on the substrate decreases. As a result, the circuit cannot be embedded.

  Moreover, in the thermosetting resin composition concerning this invention, the dielectric property of said (v) curable resin can be made more preferable by prescribing | regulating the dielectric loss tangent. Specifically, a cured resin can be obtained by heating the thermosetting resin composition under a temperature condition of 150 ° C. to 250 ° C. for 1 to 5 hours. In this cured resin, at a frequency in the GHz band. The dielectric loss tangent is preferably 0.025 or less, more preferably 0.020 or less, and further preferably 0.015 or less.

  In addition, the thermosetting resin composition according to the present invention includes (A) a polyimide resin component, (B) an epoxy resin component, and (C) an epoxy curing agent component. Excellent physical properties can be exhibited as a functional resin composition. In particular, in order to compensate for the low processability, that is, the low resin fluidity, which is a disadvantage of the polyimide resin, appropriate types of the components (B) and (C) are selected. Moreover, by blending an appropriate amount of the components (B) and (C) with the component (A) so as not to lose the excellent physical properties of the polyimide resin, the excellent physical properties of the polyimide resin can be maintained, and the polyimide resin It becomes possible to obtain a thermosetting resin composition that overcomes the disadvantages. As a result, the thermosetting resin composition according to the present invention has several advantages derived from the characteristics of the polyimide resin.

  Although the thermosetting resin composition according to the present invention has excellent mechanical properties, specifically, the tensile strength is preferably 50 MPa or more, more preferably 80 MPa or more, and further preferably 100 MPa or more. preferable. Here, “tensile strength” refers to the maximum stress that can be withstood by a material before it breaks in tension. Furthermore, the tensile elongation is preferably 3% or more, more preferably 5% or more, and further preferably 10% or more. Here, “tensile elongation” refers to the percentage of the difference between the length when stretched and the original length to the original length. The excellent mechanical properties of the thermosetting resin composition according to the present invention are based on the fact that an appropriate amount of a polyimide resin originally excellent in mechanical properties is blended in the thermosetting resin composition.

  Although the thermosetting resin composition according to the present invention exhibits excellent electrical insulation, specifically, the volume resistance at room temperature is preferably 10E + 15 Ω · cm or more, more preferably 10E + 16 Ω · cm or more. . In addition, it has excellent electrical insulation at high temperatures, and preferably has a volume resistance of 10E + 14 Ω · cm or more at 125 ° C., which is set as a high temperature region of an assumed use environment, and more preferably 10E + 15 Ω · cm or more. Preferably, it is 10E + 16 Ω · cm or more. The excellent electrical insulation of the thermosetting resin composition according to the present invention is based on the fact that an appropriate amount of a polyimide resin originally excellent in electrical insulation is blended in the thermosetting resin composition according to the present invention. In addition, normal temperature here refers to the inside of the range of general room temperature, More specifically, shall refer to the inside of the range of 15-25 degreeC.

  The thermosetting resin composition according to the present invention comprises the components (A) to (C) as essential components, and epoxy groups contained in the thermosetting resin composition and hydroxyl groups generated by the ring-opening reaction. 150 ° C. of at least one epoxy resin blended so that the total number of moles is 0.2 mol / 100 g or less and contained in the (B) epoxy resin component contained in the thermosetting resin composition ICI viscosity is 0.5 Pa · s or less. Thus, (i) adhesion between the thermosetting resin composition and an adherend such as a conductor or a printed wiring board, and (ii) processing at the time of bonding the thermosetting resin composition to the conductor or the printed wiring board. (Iii) In addition to being able to improve various properties such as heat resistance such as (iii) low thermal expansion coefficient and high thermal decomposition temperature, (iv) excellent resin fluidity and (v) dielectric properties Can be a thing. Moreover, in the obtained thermosetting resin composition and cured resin, since these various characteristics can be realized in a balanced manner, the present invention provides a flexible printed wiring board, a rigid printed wiring board, a multilayer flexible printed wiring board, and a multilayer rigid wiring board. It can be preferably used for the production of printed wiring boards such as a build-up wiring board and the like, and also imparts various characteristics to a printed wiring board obtained using the thermosetting resin composition of the present invention. be able to.

(II) Each component of the thermosetting resin composition according to the present invention Next, the components (A) to (C) used in the present invention, and (D) other components will be described more specifically. .

(II-1) (A) Polyimide resin component The (A) polyimide resin component used by this invention should just contain at least 1 type of polyimide resin. The thermosetting resin composition according to the present invention is provided with sufficient heat resistance by containing this (A) polyimide resin component, and has excellent flex resistance and excellent resistance to the cured resin after curing. Mechanical properties and chemical resistance can be imparted, and excellent dielectric properties can also be imparted.

  The polyimide resin used as the (A) polyimide resin component in the present invention is not particularly limited, but is preferably a soluble polyimide resin that dissolves in an organic solvent. Here, the soluble polyimide resin refers to a polyimide resin that dissolves in an organic solvent in an amount of 1% by weight or more in a temperature range of 15 ° C to 100 ° C. Examples of the organic solvent include ether solvents such as dioxane, dioxolane and tetrahydrofuran; acetamide solvents such as N, N-dimethylformamide and N, N-diethylacetamide; formamide solvents such as N, N-diethylformamide and the like. Examples of the solvent include at least one solvent selected from N, N-dimethylacetamide; pyrrolidone solvents such as N-methyl-2-pyrrolidone and N-vinyl-2-pyrrolidone. These solvent may use only 1 type and may use it combining 2 or more types by arbitrary ratios.

  If the said soluble polyimide resin is used, when thermosetting the thermosetting resin composition concerning this invention, the process for high temperature and a long time is not required. Therefore, the epoxy resin component (B) described later can be cured efficiently. That is, in the present invention, it is preferable to use a soluble polyimide resin as one of the (A) polyimide resin components in terms of (ii) improving workability and handleability.

  The said polyimide resin can be manufactured by a conventionally well-known method. Specifically, for example, it can be obtained by chemically or thermally imidizing polyamic acid (polyamic acid) which is a precursor material of polyimide resin. Hereinafter, a method for producing a polyimide resin from a polyamic acid by imidization will be described in detail.

<Production (synthesis) method of polyamic acid>
The polyamic acid contains, as monomer raw materials, an (A-1) acid dianhydride component containing at least one acid dianhydride and a (A-2) diamine component containing at least one diamine in an organic solvent. It can synthesize | combine by making it react with. At this time, the total amount of the (A-1) acid dianhydride component and the total amount of the (A-2) diamine component are mixed so as to be substantially equimolar. Accordingly, when two or more compounds are used as (A-1) acid dianhydride component and (A-2) diamine component, respectively, the molar ratio of the total amount of plural diamines and the molar ratio of the total amount of plural acid dianhydrides Are adjusted so as to be substantially equimolar, a polyamic acid copolymer can be obtained.

  The method of reacting the (A-1) acid dianhydride component and the (A-2) diamine component is not particularly limited, but as a typical method, (A-2) the diamine component is organic. A method of obtaining a solution obtained by dissolving a polyamic acid in an organic solvent (hereinafter referred to as a polyamic acid solution) by dissolving in a solvent and then adding and mixing the (A-1) acid dianhydride component. Can be mentioned. Here, “dissolved” means a state in which the solvent completely dissolves the solute and a state in which the solute is uniformly dispersed or diffused in the solvent and is substantially in a dissolved state. Shall be included.

  Note that the addition of the (A-1) acid dianhydride component and the (A-2) diamine component is not limited to the above order, and those skilled in the art can appropriately change, modify, and modify the addition method. Can be modified. For example, the (A-1) acid dianhydride component may be first dissolved or dispersed in an organic solvent, and then the (A-2) diamine component may be added. Alternatively, first, an appropriate amount of the (A-2) diamine component is added to the organic solvent, and then an amount of (A-1) acid dianhydride that is excessive relative to the total amount of the added (A-2) diamine component. It may be a method of adding a physical component and then adding (A-2) a diamine component in an amount corresponding to the excess amount of (A-1) acid dianhydride.

  The reaction conditions (polyamide acid synthesis conditions) of the above (A-1) acid dianhydride component and (A-2) diamine component are not particularly limited, and the acid dianhydride and diamine which are monomer raw materials Any conditions may be used as long as they can be polymerized. However, among the reaction conditions, the reaction temperature is preferably 80 ° C. or lower, and more preferably in the range of 0 to 50 ° C. Moreover, what is necessary is just to set reaction time arbitrarily in the range of 30 minutes-50 hours. If the reaction temperature and reaction time are within these ranges, the polyamic acid can be efficiently synthesized.

  The organic solvent used for the synthesis of the polyamic acid is not particularly limited as long as it is an organic polar solvent. However, it is preferable to select an organic solvent that is a good solvent for the polyamic acid and has a boiling point as low as possible. When such an organic solvent is used, (1) the viscosity of the reaction solution increases when the monomer raw material components (A-1) and (A-2) are subjected to a polymerization reaction (during synthesis of polyamic acid). This is preferable in terms of the production process from the viewpoint of making it easy to stir and suppressing (2) easy drying of the resulting polyimide resin.

  Specific examples of the organic solvent include sulfoxide solvents such as dimethyl sulfoxide and diethyl sulfoxide; formamide solvents such as N, N-dimethylformamide and N, N-diethylformamide; N, N-dimethylacetamide and N, Acetamide solvents such as N-diethylacetamide; Pyrrolidone solvents such as N-methyl-2-pyrrolidone and N-vinyl-2-pyrrolidone; Phenol, o-cresol, m-cresol, p-cresol, xylenol, halogenated phenol And phenol solvents such as catechol; hexamethylphosphoramide, γ-butyrolactone, and the like. These solvent may use only 1 type and may use it combining 2 or more types by arbitrary ratios. Furthermore, you may use it combining aromatic hydrocarbons, such as xylene or toluene, with respect to the said organic solvent as needed.

<(A-1) Acid dianhydride component>
The (A-1) acid dianhydride component as a monomer raw material used for the synthesis of the polyamic acid is not particularly limited, and particularly, in the finally obtained polyimide resin, solubility in various organic solvents, If various properties such as heat resistance and compatibility with the other essential components (B) to (C) can be sufficiently realized, a known acid dianhydride can be used. Of these, aromatic tetracarboxylic dianhydrides are preferred. In particular, the aromatic tetracarboxylic dianhydride has the following general formula (1)

(Wherein, X ¹ is selected from the group consisting of —O—, —CO—, —O—X ² —O—, —COO—X ² —OCO—, —C (CF ₃ ) ₂ —. A divalent group selected, and X ² is preferably a compound having a structure represented by: Only one type of acid dianhydride having such a structure may be used, or two or more types may be used in combination at any ratio.

In the acid dianhydride having the structure represented by the general formula (1) (referred to as “acid dianhydride of the formula (1)” for convenience of explanation), the thermosetting resin composition finally obtained X ¹ in the general formula (1) is —O—X ² —O— or —COO—X ² —OCO— because the dielectric properties and heat resistance of the product and the cured resin can be made excellent. Preferably there is. Here, X ² is a group of formulas (1-1) shown below.

Or a divalent aromatic organic group selected from the following general formula (1-2)

( _Wherein X ³ is a divalent group selected from the group consisting of —C _p H _2p —, —C (═O) —, —SO ₂ —, —O—, and —S—). And p is an integer of 1 or more and 5 or less) and is preferably any one of divalent aromatic organic groups having a structure represented by:

  Among the above aromatic tetracarboxylic dianhydrides, it is particularly preferable to use 4,4 '-(4,4'-isopropylidenediphenoxy) bisphthalic dianhydride represented by the following structural formula.

  This 4,4 ′-(4,4′-isopropylidenediphenoxy) bisphthalic dianhydride has solubility in various organic solvents, heat resistance and (B) epoxy for the resulting polyamic acid and polyimide resin. Various properties such as compatibility with the resin component and (C) epoxy curing agent component, dielectric properties and the like can be made sufficient, and the balance of the properties can also be made good. In addition, the compound used as the (A-1) acid dianhydride component has an advantage that it is easily available.

  Further, it is particularly preferable to use 4,4'-hexafluoroisopropylidenediphthalic anhydride as the aromatic tetracarboxylic dianhydride. This 4,4′-hexafluoroisopropylidenediphthalic anhydride is soluble in various organic solvents, heat resistance, (B) epoxy resin component and (C) epoxy with respect to the resulting polyamic acid and polyimide resin. While improving compatibility with a hardening | curing agent component, it can be excellent in especially a dielectric characteristic, and the balance of each characteristic can also be made favorable. In addition, the compound used as the (A-1) acid dianhydride component has an advantage that it is easily available.

  As other acid dianhydride components represented by the formula (1) that can be used as the above (A-1) acid dianhydride component, specifically, for example, ethylenebis (trimellitic acid monoester acid anhydride) ) Can be preferably used.

  As the (A-1) acid dianhydride component, a plurality of types of compounds (acid dianhydride) can be used. Therefore, in the present invention, at least one acid dianhydride is used as the above general formula (1). An acid dianhydride having a structure represented by may be used. That is, as the (A-1) acid dianhydride component, it is sufficient that at least one acid dianhydride of the above-described formula (1) is contained, and two or more of them are optionally mixed in any proportion. It may be contained in combination, and may further contain an acid dianhydride other than the acid dianhydride of the above formula (1) (hereinafter, other acid dianhydrides).

  The content of the acid dianhydride of the above formula (1) in the acid dianhydride component (A-1), that is, the ratio of the acid dianhydride of the formula (1) in all the acid dianhydrides is all When the acid dianhydride component is 100 mol%, it is preferably 50 mol% or more. If the content of the acid dianhydride of formula (1) is 50 mol% or more, the resulting polyamic acid and polyimide resin have solubility in various organic solvents, (B) epoxy resin component and (C) epoxy curing Various properties such as compatibility with the agent component and dielectric properties can be made excellent.

  Although it does not specifically limit as another acid dianhydride which can be used as said (A-1) acid dianhydride component, It is an aromatic which has structures other than the structure represented by the said General formula (1). Tetracarboxylic dianhydride can be preferably used. Specifically, for example, pyromellitic dianhydride [1,2,4,5-benzenetetracarboxylic dianhydride], 3,3 ′, 4,4′-diphenylsulfone tetracarboxylic dianhydride, 1,4,5,8-naphthalenetetracarboxylic dianhydride, 2,3,6,7-naphthalenetetracarboxylic dianhydride, 3,3 ′, 4,4′-dimethyldiphenylsilanetetracarboxylic dianhydride 1,2,3,4-furantetracarboxylic dianhydride, 4,4′-bis (3,4-dicarboxyphenoxy) diphenylpropanoic dianhydride, 3,3 ′, 4,4′- Biphenyltetracarboxylic dianhydride, 2,3,3 ′, 4′-biphenyltetracarboxylic dianhydride, p-phenylenediphthalic anhydride and the like can be mentioned. These other acid dianhydrides may be used alone or in combination of two or more at any ratio.

<(A-2) Diamine component>
The (A-2) diamine component as a monomer raw material used for the synthesis of the polyamic acid is not particularly limited, and in particular, in the finally obtained polyimide resin, solubility in various organic solvents, heat resistance, If various characteristics such as solder heat resistance, PCT resistance, low water absorption, and thermoplasticity can be sufficiently realized, a known diamine can be used. Of these, aromatic diamines are preferred. In particular, the aromatic diamine includes phenylenediamines such as 1,3-phenylenediamine and 1,2-phenylenediamine, and the following general formula (2):

(In the formula, Y ^{1 s} independently represent —C (═O) —, —SO ₂ —, —O—, —S—, — (CH ₂ ) _m —, —NHCO—, —C It represents a divalent group selected from the group consisting of (CH ₃ ) ₂ —, —C (CF ₃ ) ₂ —, and —C (═O) O—, or a direct bond, and each R is independently And a hydrogen atom, a halogen atom, or an alkyl group having 1 to 4 carbon atoms, and m and n are each independently an integer of 1 to 5). Is preferable, and a compound having a structure represented by the general formula (2) is more preferable. Note that the direct bond referred to here means that two benzene rings are bonded to each other by directly bonding carbon contained in each of the two benzene rings.

  Specific examples of the diamine having the structure represented by the general formula (2) (referred to as “diamine of formula (2)” for convenience of description) include, for example, bis [4- (3-aminophenoxy). ) Phenyl] methane, bis [4- (4-aminophenoxy) phenyl] methane, 1,1-bis [4- (3-aminophenoxy) phenyl] ethane, 1,1-bis [4- (4-amino) Phenoxy) phenyl] ethane, 1,2-bis [4- (3-aminophenoxy) phenyl] ethane, 1,2-bis [4- (4-aminophenoxy) phenyl] ethane, 2,2-bis [4- Bis [((3-aminophenoxy) phenyl] propane, 2,2-bis [4- (4-aminophenoxy) phenyl] propane, 2,2-bis [4- (3-aminophenoxy) phenyl] butane, etc. A Nophenoxy) phenyl] alkanes; 2,2-bis [3- (3-aminophenoxy) phenyl] -1,1,1,3,3,3-hexafluoropropane, 2,2-bis [4- ( Bis [(aminophenoxy) phenyl] fluoroalkanes such as 4-aminophenoxy) phenyl] -1,1,1,3,3,3-hexafluoropropane; 1,3-bis (3-aminophenoxy) benzene; 1,3-bis (4-aminophenoxy) benzene, 1,4-bis (3-aminophenoxy) benzene, 1,4-bis (4-aminophenoxy) benzene, 4,4′-bis (4-aminophenoxy) ) Bis (aminophenoxy) benzene compounds such as biphenyl; bis [4- (3-aminophenoxy) phenyl] ketone, bis [4- (4-aminophenoxy) Bis [aminophenoxy) ketone compounds such as enyl] ketone; Bis [(aminophenoxy) such as bis [4- (3-aminophenoxy) phenyl] sulfide, bis [4- (4-aminophenoxy) phenyl] sulfide Phenyl] sulfide compounds; bis [(aminophenoxy) phenyl] sulfone compounds such as bis [4- (3-aminophenoxy) phenyl] sulfone and bis [4- (4-aminophenoxy) phenyl] sulfone; Bis [(aminophenoxy) phenyl] ether compounds such as 4- (3-aminophenoxy) phenyl] ether and bis [4- (4-aminophenoxy) phenyl] ether; 1,4-bis [4- (3 -Aminophenoxy) benzoyl] benzene, 1,3-bis [4- (3-aminophenoxy) Bis [(aminophenoxy) benzoyl] benzene compounds such as benzoyl] benzene; 4,4′-bis [3- (4-aminophenoxy) benzoyl] diphenyl ether, 4,4′-bis [3- (3- Bis [(aminophenoxy) benzoyl] diphenyl ether compounds such as aminophenoxy) benzoyl] diphenyl ether; benzophenone compounds such as 4,4′-bis [4- (4-amino-α, α-dimethylbenzyl) phenoxy] benzophenone , Such as 4,4′-bis [4- (4-amino-α, α-dimethylbenzyl) phenoxy] diphenylsulfone, bis [4- {4- (4-aminophenoxy) phenoxy} phenyl] sulfone and the like (phenoxy ) Phenyl sulfone compounds; 1,4-bis [4- (4-aminophenoxy) ) -Α, α-dimethylbenzyl] benzene, bis [(aminophenoxy) dimethylbenzene] benzene compounds such as 1,3-bis [4- (4-aminophenoxy) -α, α-dimethylbenzyl] benzene; Etc. These diamines of the formula (2) may be used alone or in combination of two or more at any ratio.

  Among the diamines of the above formula (2), the following general formula (2-1)

(However, in the formula, each Y ¹ independently represents —C (═O) —, —SO ₂ —, —O—, —S
_{-, - (CH 2) m} -, - NHCO -, - C (CH 3) 2 -, - C (CF 3) 2 -, and, -C (=
O) represents a divalent group selected from the group consisting of O- or a direct bond, and each R independently represents a hydrogen atom, a halogen atom or an alkyl group having 1 to 4 carbon atoms, m , N are each independently an integer of 1 or more and 5 or less), that is, a diamine having an amino group at the meta position can be more preferably used. If the diamine has an amino group at the meta position as shown in the formula (2), the resulting polyimide resin is more soluble in various organic solvents than when a diamine having an amino group at the para position is used. It can be excellent.

  Specific examples of the diamine having the structure represented by the general formula (2-1) (referred to as “meta-position diamine” for the sake of convenience) include, for example, examples of the diamine of the formula (2) described above. Among the compounds mentioned as bis [4- (3-aminophenoxy) phenyl] methane, 1,1-bis [4- (3-aminophenoxy) phenyl] ethane, 1,2-bis [4- (3- Aminophenoxy) phenyl] ethane, 2,2-bis [4- (3-aminophenoxy) phenyl] propane, 2,2-bis [4- (3-aminophenoxy) phenyl] butane, 2,2-bis [3 -(3-Aminophenoxy) phenyl] -1,1,1,3,3,3-hexafluoropropane, 1,3-bis (3-aminophenoxy) benzene, 1,4-bis (3-aminophenoxy) Benze Bis [4- (3-aminophenoxy) phenyl] ketone, bis [4- (3-aminophenoxy) phenyl] sulfide, bis [4- (3-aminophenoxy) phenyl] sulfone, bis [4- (3- Aminophenoxy) phenyl] ether, 1,4-bis [4- (3-aminophenoxy) benzoyl] benzene, 1,3-bis [4- (3-aminophenoxy) benzoyl] benzene, 4,4′-bis [ And 3- (3-aminophenoxy) benzoyl] diphenyl ether. These meta diamines may be used alone or in combination of two or more at any ratio.

  Of these, it is particularly preferable to use 1,3-bis (3-aminophenoxy) benzene as the meta-position diamine. If the 1,3-bis (3-aminophenoxy) benzene is used, the final thermosetting resin composition has excellent solubility in various organic solvents, solder heat resistance, and PCT resistance. It becomes possible.

  Further, as the diamine contained in the (A-2) diamine component, a diamine having a hydroxyl group (—OH) and / or a carboxyl group (—COOH) (referred to as “hydroxyl group / carboxyl group-containing diamine” for convenience of explanation). Can be mentioned. If this hydroxyl group / carboxyl group-containing diamine is used, hydroxyl groups and / or carboxyl groups can be introduced into the resulting polyimide resin.

  When at least one of a hydroxyl group and a carboxyl group is introduced into the polyimide resin, curing of the epoxy resin component (B) described later can be promoted in the thermosetting resin composition. Therefore, when hardening a thermosetting resin composition, it becomes possible to perform the thermosetting of the (B) epoxy resin component at low temperature or for a short time. Furthermore, since the (B) epoxy resin component reacts with a hydroxyl group or a carboxyl group, the polyimide resins are cross-linked via the epoxy resin. Therefore, in the cured resin after curing, the molecular structure is strengthened.

  Therefore, by using the hydroxyl group / carboxyl group-containing diamine to obtain a polyimide resin into which a hydroxyl group and / or a carboxyl group have been introduced, the thermosetting resin composition and the cured resin finally obtained have heat resistance, Various characteristics such as solder heat resistance and PCT resistance can be further improved.

  The hydroxyl group / carboxyl group-containing diamine is not particularly limited as long as it has at least one of a hydroxyl group and a carboxyl group in its structure. Specifically, for example, diaminophenol compounds such as 2,4-diaminophenol; diaminobiphenyl compounds such as 3,3′-dihydroxy-4,4′-diaminobiphenyl; 3,3′-diamino-4, 4'-dihydroxybiphenyl, 4,4'-diamino-3,3'-dihydroxybiphenyl, 4,4'-diamino-2,2'-dihydroxybiphenyl, 4,4'-diamino-2,2 ', 5 Hydroxybiphenyl compounds such as 5′-tetrahydroxybiphenyl; 3,3′-diamino-4,4′-dihydroxydiphenylmethane, 4,4′-diamino-3,3′-dihydroxydiphenylmethane, 4,4′-diamino -2,2'-dihydroxydiphenylmethane, 2,2-bis [3-amino-4-hydroxyphenyl] propane 2,2-bis [4-amino-3-hydroxyphenyl] propane, 2,2-bis [3-amino-4-hydroxyphenyl] hexafluoropropane, 4,4′-diamino-2,2 ′, 5 Hydroxydiphenylalkanes such as 5′-tetrahydroxydiphenylmethane; 3,3′-diamino-4,4′-dihydroxydiphenyl ether, 4,4′-diamino-3,3′-dihydroxydiphenyl ether, 4,4′-diamino- Hydroxydiphenyl ether compounds such as 2,2′-dihydroxydiphenyl ether and 4,4′-diamino-2,2 ′, 5,5′-tetrahydroxydiphenyl ether; 3,3′-diamino-4,4′-dihydroxydiphenylsulfone 4,4'-diamino-3,3'-dihydroxydiphenylsulfo Diphenylsulfone compounds such as 4,4′-diamino-2,2′-dihydroxydiphenylsulfone, 4,4′-diamino-2,2 ′, 5,5′-tetrahydroxydiphenylsulfone; Bis [(hydroxyphenyl) phenyl] alkanes such as [4- (4-amino-3-hydroxyphenoxy) phenyl] propane; Bis such as 4,4′-bis (4-amino-3-hydroxyphenoxy) biphenyl (Hydroxyphenoxy) biphenyl compounds; bis [(hydroxyphenoxy) phenyl] sulfone compounds such as 2,2-bis [4- (4-amino-3-hydroxyphenoxy) phenyl] sulfone; 3,5-diaminobenzoic acid Diaminobenzoic acids such as acids; 3,3′-diamino-4,4′-dicarboxybiphenyl, 4,4′-dia Carboxy such as Mino-3,3′-dicarboxybiphenyl, 4,4′-diamino-2,2′-dicarboxybiphenyl, 4,4′-diamino-2,2 ′, 5,5′-tetracarboxybiphenyl, etc. Biphenyl compounds; 3,3′-diamino-4,4′-dicarboxydiphenylmethane, 4,4′-diamino-3,3′-dihydroxydiphenylmethane, 4,4′-diamino-2,2′-dihydroxy Diphenylmethane, 2,2-bis [4-amino-3-carboxyphenyl] propane, 2,2-bis [3-amino-4-carboxyphenyl] hexafluoropropane, 4,4′-diamino-2,2 ′, Carboxydiphenylalkanes such as carboxydiphenylmethane such as 5,5′-tetracarboxydiphenylmethane; -4,4'-dicarboxydiphenyl ether, 4,4'-diamino-3,3'-dicarboxydiphenyl ether, 4,4'-diamino-2,2'-dicarboxydiphenyl ether, 4,4'-diamino-2 Carboxydiphenyl ether compounds such as 2,2 ', 5,5'-tetracarboxydiphenyl ether; 3,3'-diamino-4,4'-dicarboxydiphenylsulfone, 4,4'-diamino-3,3'-dicarboxy Diphenyl sulfone compounds such as diphenyl sulfone, 4,4′-diamino-2,2′-dicarboxydiphenyl sulfone, 4,4′-diamino-2,2 ′, 5,5′-tetracarboxydiphenyl sulfone; Bis [((2-bis [4- (4-amino-3-carboxyphenoxy) phenyl] propane) and the like Ruboxyphenyl) phenyl] alkanes; bis (hydroxyphenoxy) biphenyl compounds such as 4,4′-bis (4-amino-3-hydroxyphenoxy) biphenyl; 2,2-bis [4- (4- Bis [(carboxyphenoxy) phenyl] sulfone compounds such as amino-3-carboxyphenoxy) phenyl] sulfone; and the like. These hydroxyl group / carboxyl group-containing diamines may be used alone or in combination of two or more at any ratio.

  Among the above-mentioned compounds, it is particularly preferable to use 3,3′-dihydroxy-4,4′-diaminobiphenyl represented by the following structural formula as the hydroxyl group / carboxyl group-containing diamine.

  By including 3,3′-dihydroxy-4,4′-diaminobiphenyl in the (A-2) diamine component, good solder heat resistance and PCT resistance are obtained for the resulting thermosetting resin composition and cured resin. Can be given.

  Thus, the (A-2) diamine component contains at least one diamine of the above formula (2) (particularly a meta-position diamine), and further contains at least one hydroxyl group / carboxyl group-containing diamine. It is preferable that Even when the diamine of formula (2) is not included, it is preferable that at least one hydroxyl group / carboxyl group-containing diamine is included. That is, in the present invention, the (A-2) diamine component preferably contains at least one diamine of the formula (2) and / or a hydroxyl group / carboxyl group-containing diamine. Thereby, more excellent solder heat resistance and PCT resistance can be obtained with respect to the obtained thermosetting resin composition and cured resin.

  The content of the diamine of the above formula (2) in the diamine component (A-2), that is, the ratio of the diamine of the formula (2) in all the diamines is 60 mol when all the diamine components are 100 mol%. % To 99 mol% is preferable. Similarly, the content of the hydroxyl group / carboxyl group-containing diamine in the diamine component (A-2), that is, the ratio of the hydroxyl group / carboxyl group-containing diamine in all diamines was 100 mol% of all diamine components. In some cases, it is preferably 1 mol% or more and 40 mol% or less. When the content of each diamine deviates from the above range, the resulting thermosetting resin composition and cured resin tend to impair the solubility in various organic solvents, solder heat resistance, and PCT resistance.

  In addition, what is necessary is just to combine each said diamine in each arbitrary ratio, and when using together the diamine of said Formula (2), and a hydroxyl group / carboxyl group containing diamine, what is necessary is just to contain each within the said range. .

  Furthermore, the diamine component (A-2) may contain a diamine other than the diamine of the above formula (2) and the hydroxyl group / carboxyl group-containing diamine (referred to as “other diamine” for convenience of explanation). (A-2) Other diamines contained in the diamine component are not particularly limited, but aromatic diamines can be preferably used.

  Specific examples of the aromatic diamine include m-phenylenediamine, o-phenylenediamine, p-phenylenediamine, m-aminobenzylamine, p-aminobenzylamine, and bis (3-aminophenyl) sulfide. , (3-aminophenyl) (4-aminophenyl) sulfide, bis (4-aminophenyl) sulfide, bis (3-aminophenyl) sulfoxide, (3-aminophenyl) (4-aminophenyl) sulfoxide, bis (3 -Aminophenyl) sulfone, (3-aminophenyl) (4-aminophenyl) sulfone, bis (4-aminophenyl) sulfone, 3,4'-diaminobenzophenone, 4,4'-diaminobenzophenone, 3,3'- Diaminodiphenylmethane, 3,4'-diaminodiphenylmeta 4,4′-diaminodiphenylmethane, 4,4′-diaminodiphenyl ether, 3,3′-diaminodiphenyl ether, 3,4′-diaminodiphenyl ether, bis [4- (3-aminophenoxy) phenyl] sulfoxide, bis [4 -(Aminophenoxy) phenyl] sulfoxide and the like can be mentioned.

  These other diamines may be used alone or in combination of two or more in any ratio. Moreover, it is preferable that content of the other diamine in the said (A-2) diamine component is less than 10 mol% when all the diamine components are 100 mol%. If it exceeds 10 mol%, the content of the diamine of formula (2) and the hydroxyl group / carboxyl group-containing diamine may be reduced, and a polyimide resin having desired physical properties may not be obtained.

<Imidization of polyamic acid>
By mixing and stirring the (A-1) acid dianhydride component and (A-2) diamine component in an organic solvent as described in the above section <Production (synthesis) method of polyamic acid> A polyamic acid solution is obtained. A soluble polyimide resin can be obtained by imidizing the polyamic acid in the polyamic acid solution. Specific examples of imidization performed at this time include (1) thermal method, (2) chemical method, and (3) vacuum imidization method. By these methods, a polyimide resin is obtained by dehydrating and ring-closing the polyamic acid.

  The above (1) thermal method is a method in which the polyamic acid solution is heat-treated to perform dehydration and cyclization, and the specific steps thereof are not particularly limited. For example, imidization is performed by heat treatment of the polyamic acid solution. A process such as advancing the reaction and simultaneously evaporating the solvent can be mentioned. By this thermal method, a solid polyimide resin can be obtained. In addition, although the conditions of the said heat processing are not specifically limited, It is preferable to heat at the temperature of 300 degrees C or less for the time of the range of about 5 minutes-20 minutes.

  The above (2) chemical method is a method of dehydrating and ring-closing polyamic acid using a dehydrating agent, and the specific process is not particularly limited. A method of performing a dehydration reaction and evaporation of an organic solvent by adding a dehydrating agent and a catalyst that are more than the stoichiometric amount can be mentioned. By this chemical method, a solid polyimide resin can be obtained.

  Examples of the dehydrating agent include aliphatic acid anhydrides such as acetic anhydride; aromatic acid anhydrides such as benzoic anhydride; carbodiimides such as N, N′-dicyclohexylcarbodiimide and N, N′-diisopropylcarbodiimide. Can do. Examples of the catalyst include aliphatic tertiary amines such as triethylamine; aromatic tertiary amines such as dimethylaniline; heterocyclic groups such as pyridine, α-picoline, β-picoline, γ-picoline, and isoquinoline. Tertiary amines; and the like.

  In addition, it is preferable that the temperature condition at the time of (2) dehydration ring closure by a chemical method is 100 degrees C or less, and it is preferable to carry out reaction time within the range of about 1 minute-50 hours. The evaporation of the organic solvent is preferably performed at a temperature of 200 ° C. or less for a time in the range of about 5 minutes to 120 minutes.

  Further, the (3) vacuum imidization method is a method of imidizing polyamic acid by heat treatment under reduced pressure, and the specific steps thereof are not particularly limited. The heating condition may be in the range of 80 to 400 ° C., but in order to perform imidization and dehydration efficiently, the temperature is more preferably 100 ° C. or more, and further preferably 120 ° C. or more. Here, the maximum temperature in the heat treatment is preferably set to be equal to or lower than the thermal decomposition temperature of the polyimide resin, and is usually set within a temperature range of about 150 ° C. to 350 ° C., which is a complete temperature of imidization. The pressure condition is preferably low pressure. Specifically, it is preferably within a range of 0.001 to 0.9 atmosphere, more preferably within a range of 0.001 to 0.8 atmosphere, and a range of 0.001 to 0.7 atmosphere. More preferably, it is within.

  According to the above (3) vacuum imidization method, water produced by imidization can be positively removed out of the system, so that hydrolysis of polyamic acid can be suppressed. As a result, a high molecular weight polyimide resin can be obtained. Furthermore, if this method is used, one-side ring-opened product or both-side ring-opened products existing as impurities in the acid dianhydride that is a raw material of the polyamic acid can be closed, so that the molecular weight of the polyimide resin is further improved. can do.

  In the imidation methods (1) to (3) described above, the case of evaporating the solvent has been described as an example. However, the imidization method is not limited to this, and the solvent need not be evaporated. . Specifically, for example, a method of adding a polyimide resin solution obtained by the imidization method of the above (1) and (2) to a poor solvent and precipitating the polyimide resin can be mentioned. In this method, the unreacted monomer (acid dianhydride / diamine) contained in the polyimide resin solution is removed for purification. If this is dried, a higher quality solid polyimide resin can be obtained.

The poor solvent used in this method is not particularly limited as long as it is well mixed with the solvent of the polyimide resin solution, but the polyimide resin is a solvent that is difficult to dissolve. Specific examples include acetone, methanol, ethanol, isopropanol, benzene, methyl cellosolve (registered trademark), and methyl ethyl ketone. These poor solvents may use only 1 type and may use it combining 2 or more types by arbitrary ratios.
In the present invention, a generally available polyimide resin can be applied as the (A) polyimide resin component. Specifically, a polyetherimide resin (trade name; Ultem) made of Japan GE Plastics can be mentioned.

(II-2) (B) Epoxy Resin Component The (B) epoxy resin component used in the present invention may contain a compound having two or more reactive epoxy groups in the molecule, that is, an epoxy resin. At least one epoxy resin is a low-viscosity epoxy resin having an ICI viscosity of 0.5 Pa · s or less. As described above, by using such an epoxy resin component (B), it is possible to improve the resin fluidity in a semi-cured state in the thermosetting resin composition according to the present invention. Specifically, for example, the minimum melt viscosity of the thermosetting resin composition is 10 pa · s or more and 10,000 Pa · s under the condition of being in a semi-cured state and having a temperature in the range of 60 ° C. or more and 200 ° C. or less. It can be as follows. It is preferable for the present invention that the ICI viscosity is as low as possible, more preferably 0.3 Pa · s or less, and still more preferably 0.1 Pa · s or less.

  Among the epoxy resin components (B), the low viscosity epoxy resin is not particularly limited as long as the ICI viscosity satisfies the above conditions. Specifically, for example, bisphenol type epoxy resin, bisphenol A novolac epoxy resin, biphenyl epoxy resin, phenol novolac epoxy resin, alkylphenol novolac epoxy resin, polyglycol epoxy resin, cycloaliphatic epoxy resin, cresol novolac epoxy resin, glycidylamine epoxy resin, naphthalene epoxy And epoxy resins such as resins, urethane-modified epoxy resins, rubber-modified epoxy resins, and epoxy-modified polysiloxanes; halogenated epoxy resins; crystalline epoxy resins having a melting point; These epoxy resins may be used alone or in combination of two or more at any ratio.

  Among these epoxy resins, an epoxy resin having at least one aromatic ring and / or aliphatic ring in a molecular chain, a biphenyl type epoxy resin having a biphenyl skeleton, a naphthalene type epoxy resin having a naphthalene skeleton, and a crystalline epoxy having a melting point A resin is more preferably used. These epoxy resins have a relatively low ICI viscosity, and thus have a high effect of lowering the melt viscosity of the thermosetting resin, which is an effect of the present invention. In addition, these epoxy resins are easily available and have excellent compatibility with the components (A), (B), and (C). Furthermore, excellent heat resistance and insulation can be imparted to the cured resin after curing.

  Among the above epoxy resins, the following group of formulas (3)

(However, in the formula, p, q, and r each independently represent an arbitrary integer)
An epoxy resin represented by or a crystalline epoxy resin can be more preferably used. If these epoxy resins are used, various properties such as dielectric properties, heat resistance and circuit embedding properties can be imparted to the thermosetting resin composition and the cured resin, and a good balance of these properties can be obtained. Can be.

  Furthermore, in the present invention, it is particularly preferable to use the crystalline epoxy resin. The crystalline epoxy resin has a particularly low ICI viscosity, and the melt viscosity of the thermosetting resin composition is specifically reduced, so that the circuit embedding property can be greatly improved (that is, the resin fluidity can be improved). ).

  The crystalline epoxy resin is not particularly limited as long as it is an epoxy resin having a melting point and having a structure including a crystal structure. Specifically, for example, trade name: YX4000H (Japan Epoxy Resin Co., Ltd.) Company name, biphenyl type epoxy resin), trade name: EXA7337 (manufactured by Dainippon Ink Industries, Ltd., xanthene type epoxy resin) and the like are preferably used.

  Here, the lower limit of the melting point of the crystalline epoxy resin is preferably 60 ° C. or higher, and more preferably 80 ° C. or higher. The upper limit of the melting point is preferably 220 ° C. or less, and more preferably 200 ° C. or less. Therefore, the melting point of the crystalline epoxy resin is preferably in the range of 60 ° C. or higher and 220 ° C. or lower. When the melting point is less than 60 ° C., when the thermosetting resin composition is molded into a sheet, phase separation tends to occur during molding. Therefore, the (B) epoxy resin component is deposited on the sheet surface or the sheet is sticky. On the other hand, when melting | fusing point exceeds 220 degreeC, the temperature which bonds and processes a thermosetting resin composition on a printed wiring board etc. will become high.

  In addition, it is preferable that the epoxy resin used as (B) epoxy resin component is a high purity epoxy resin, even if it is any epoxy resin mentioned above. In the thermosetting resin composition and the cured resin thus obtained, highly reliable electrical insulation can be realized. In the present invention, the high purity standard is the concentration of halogen or alkali metal contained in the epoxy resin. Specifically, the concentration of halogen or alkali metal contained in the epoxy resin is preferably 25 ppm or less, more preferably 15 ppm or less when extracted under the conditions of 120 ° C. and 2 atm. . When the content concentration of halogen or alkali metal is higher than 25 ppm, the reliability of electrical insulation is impaired in the cured resin after curing.

  In the present invention, it is essential that the number of moles of the epoxy group contained in the thermosetting resin composition and the hydroxyl group generated by the ring-opening reaction be 0.2 mol / 100 g or less. Therefore, (B) the epoxy resin component used in the present invention should determine the blending amount of (A) the polyimide resin component and (C) the epoxy curing agent component in consideration of its epoxy value (also referred to as epoxy equivalent). is there. That is, in order to develop the resin composition of the present invention with excellent dielectric properties, resin fluidity, heat resistance, adhesiveness, electrical insulation, etc. in a well-balanced manner, the epoxy group and the hydroxyl group generated by the ring-opening reaction thereof are used. It is important that the number is 0.2 mol / 100 g or less, and (B) an epoxy resin component having an appropriate epoxy value for determining the blending amounts of (A), (B), and (C) Is preferably selected. For this purpose, the epoxy value of the (B) epoxy resin component is preferably 150 g / eq or more, more preferably 170 g / eq or more, and most preferably 190 g / eq or more. Further, the upper limit value of the epoxy value of the (B) epoxy resin component is preferably 700 g / eq or less, more preferably 500 g / eq or less, and most preferably 300 g / eq or less. Therefore, the epoxy value of the epoxy resin used as the (B) epoxy resin component is preferably in the range of 150 g / eq to 700 g / eq.

  In order to make the number of moles of the hydroxyl group generated by the epoxy group contained in the thermosetting resin composition and the ring-opening reaction thereof to be 0.2 mol / 100 g or less when the epoxy value of the epoxy resin is less than 150, (B) The compounding quantity of an epoxy resin must be decreased, and the resin fluidity | liquidity of the thermosetting resin composition of this invention will become low. On the other hand, when the epoxy value exceeds 700 g / eq, the crosslink density in the cured resin is lowered, so that the heat resistance is impaired.

(II-3) (C) Epoxy curing agent component The (C) epoxy curing agent component used in the present invention is not particularly limited as long as it is a compound having two or more active hydrogens in one molecule. . Examples of active hydrogen sources include amino groups, carboxyl groups, phenolic hydroxyl groups, alcoholic hydroxyl groups, thiol groups, and the like, and compounds having these functional groups can be used as the (C) epoxy curing agent component of the present invention. It is. Among these, when an amine-based epoxy curing agent having an amino group and a polyphenol-based epoxy curing agent having a phenolic hydroxyl group are used, the thermosetting resin composition of the present invention is excellent in the property balance, and thus can be preferably used.

  Examples of the polyphenol type epoxy curing agent used in the present invention include phenol novolak, xylylene novolak, bisphenol A novolak, triphenylmethane novolak, biphenyl novolak, dicyclopentadiene phenol novolak and the like. In order to impart excellent dielectric properties, those having a large hydroxyl equivalent are preferred, and the hydroxyl equivalent is preferably 100 g / eq or more, more preferably 150 g / eq or more, and even more preferably 200 g / eq or more.

  In the present invention, it is particularly preferable to use an amine-based epoxy curing agent as the (C) epoxy curing agent component, which can impart good resin fluidity to the thermosetting resin composition, and is also a cured resin after curing. Good heat resistance can be imparted.

  The amine-based epoxy curing agent component used in the present invention only needs to contain at least one amine compound. The amine-based epoxy curing agent component is not particularly limited. For example, monoamines such as aniline, benzylamine, aminohexane, etc .; (A-2) used in the production of the polyamic acid described above are exemplified as the diamine component. Various diamines; polyamines such as diethylenetriamine, tetraethylenepentamine, and pentaethylenehexamine; Among these amines, it is preferable to use an aromatic diamine, preferably an aromatic diamine having a molecular weight of 300 or more, and an aromatic diamine having a molecular weight in the range of 300 to 600. More preferably. Thereby, favorable heat resistance and dielectric properties can be given to the cured resin after curing.

  When the molecular weight of the aromatic diamine is less than 300, in the cured resin after curing, the number of polar groups contained in the structure increases, so that the dielectric characteristics are impaired. That is, the dielectric constant and dielectric loss tangent of the cured resin are increased. On the other hand, when the molecular weight exceeds 600, the crosslink density in the cured resin is lowered, so that the heat resistance may be impaired.

  The aromatic diamine is not particularly limited. Specifically, for example, 1,4-diaminobenzene, 1,3-diaminobenzene, 2,5-dimethyl-1,4-diaminobenzene, 1, 2-diaminobenzene, benzidine, 3,3′-dichlorobenzidine, 3,3′-dimethylbenzidine, 3,3′-dimethoxybenzidine, 3,3′-dihydroxybenzidine, 3,3 ′, 5,5′-tetra Methylbenzidine, 2,2′-dimethyl-4,4′-diaminobiphenyl, 2,2′-bis (trifluoromethyl) -4,4′-diaminobiphenyl, 3,3′-diaminodiphenylmethane, 3,4′- Diaminodiphenylmethane, 4,4'-diaminodiphenylmethane, 4,4'-diaminodiphenylpropane, 4,4'-diaminodiph Nylhexafluoropropane, 4,4′-diaminodiphenylsilane, 4,4′-diaminodiphenyldiethylsilane, 4,4′-diaminodiphenylethylphosphine oxide, 4,4′-diaminodiphenyl N-methylamine, 4,4 '-Diaminodiphenyl N-phenylamine, 3,3'-diaminodiphenyl ether, 3,4'-diaminodiphenyl ether, 4,4'-diaminodiphenyl ether, 3,3'-diaminodiphenyl thioether, 3,4'-diaminodiphenyl thioether 4,4′-diaminodiphenylthioether, 3,3′-diaminodiphenylsulfone, 3,4′-diaminodiphenylsulfone, 4,4′-diaminodiphenylsulfone, 3,3′-diaminobenzanilide, 3,4 ′ -Zia Nobenzanilide, 4,4′-diaminobenzanilide, 3,3′-diaminobenzophenone, 3,4′-diaminobenzophenone, 4,4′-diaminobenzophenone, 1,3-bis (3-aminophenoxy) benzene, 1,3-bis (4-aminophenoxy) benzene, 1,4-bis (3-aminophenoxy) benzene, 1,4-bis (4-aminophenoxy) benzene, bis [4- (3-aminophenoxy) phenyl ] Methane, bis [4- (4-aminophenoxy) phenyl] methane, 1,1-bis [4- (3-aminophenoxy) phenyl] ethane, 1,1-bis [4- (4-aminophenoxy) Phenyl] ethane, 1,2-bis [4- (3-aminophenoxy) phenyl] ethane, 1,2-bis [4- (4-aminophenoxy) phenyl Enyl] ethane, 2,2-bis [4- (3-aminophenoxy) phenyl] propane, 2,2-bis [4- (4-aminophenoxy) phenyl] propane, 2,2-bis [4- (3 -Aminophenoxy) phenyl] butane, 2,2-bis [4- (4-aminophenoxy) phenyl] butane, 2,2-bis [4- (3-aminophenoxy) phenyl] -1,1,1,3 , 3,3-hexafluoropropane, 2,2-bis [4- (4-aminophenoxy) phenyl] -1,1,1,3,3,3-hexafluoropropane, 4,4′-bis (3 -Aminophenoxy) biphenyl, 4,4'-bis (4-aminophenoxy) biphenyl, bis [4- (3-aminophenoxy) phenyl] ketone, bis [4- (4-aminophenoxy) phenyl] ketone Bis [4- (3-aminophenoxy) phenyl] sulfide, bis [4- (4-aminophenoxy) phenyl] sulfide, bis [4- (3-aminophenoxy) phenyl] sulfone, bis [4- (4- Aminophenoxy) phenyl] sulfone, bis [4- (3-aminophenoxy) phenyl] ether, bis [4- (4-aminophenoxy) phenyl] ether, 1,4-bis [4- (3-aminophenoxy) benzoyl Benzene, 1,3-bis [4- (3-aminophenoxy) benzoyl] benzene, 4,4′-bis [3- (4-aminophenoxy) benzoyl] diphenyl ether, 4,4′-bis [3- ( 3-Aminophenoxy) benzoyl] diphenyl ether, 4,4′-bis [4- (4-amino-α, α-dimethylbenzen) ) Phenoxy] benzophenone, 4,4′-bis [4- (4-amino-α, α-dimethylbenzyl) phenoxy] diphenylsulfone, bis [4- {4- (4-aminophenoxy) phenoxy} phenyl] sulfone, 1,4-bis [4- (4-aminophenoxy) -α, α-dimethylbenzyl] benzene, 1,3-bis [4- (4-aminophenoxy) -α, α-dimethylbenzyl] benzene, 1, Examples include 5-diaminonaphthalene and 9,9′-bis (4-aminophenyl) fluorene. These diamines may be used alone or in combination of two or more at any ratio.

  Among these, in particular, 2,2-bis [4- (3-aminophenoxy) phenyl] propane, 2,2-bis [4- (4-aminophenoxy) phenyl] propane, 2,2-bis [3- (3-Aminophenoxy) phenyl] -1,1,1,3,3,3-hexafluoropropane, 2,2-bis [4- (4-aminophenoxy) phenyl] -1,1,1,3 3,3-hexafluoropropane, bis [4- (3-aminophenoxy) phenyl] sulfone, bis [4- (4-aminophenoxy) phenyl] sulfone, bis [4- (3-aminophenoxy) phenyl] ether, Bis [4- (4-aminophenoxy) phenyl] ether can be more preferably used.

  These compounds are preferable not only from the viewpoint of easy handling and availability such as being easily dissolved in a solvent, but also by containing these compounds in the (B) amine component, thereby providing heat resistance to a cured resin after curing ( The glass transition temperature is high), and various properties such as dielectric properties can be made excellent.

(II-4) (D) Other components The thermosetting resin composition according to the present invention includes (D) other components other than the components (A) to (C) as necessary. It may be. (D) Other components are not particularly limited. Specifically, for example, (D-1) a curing accelerator for promoting the reaction between the epoxy resin component and the epoxy curing agent component, ( D-2) Inorganic filler, (D-3) thermosetting resin component, etc. can be mentioned.

  The (D-1) curing accelerator used in the present invention is not particularly limited. Specifically, for example, imidazole compounds, phosphine compounds such as triphenylphosphine; tertiary amine systems, Examples include amine compounds such as trimethanolamine, triethanolamine, and tetraethanolamine; borate compounds such as 1,8-diaza-bicyclo [5,4,0] -7-undecenium tetraphenylborate. it can. These curing accelerators may be used alone or in combination of two or more at any ratio. Among these, imidazole compounds are preferable. Specifically, for example, imidazole, 2-ethylimidazole, 2-ethyl-4-methylimidazole, 2-phenylimidazole, 2-undecylimidazole, 1-benzyl-2-methylimidazole, 2-heptadecylimidazole, 2 -Imidazoles such as isopropylimidazole, 2,4-dimethylimidazole, 2-phenyl-4-methylimidazole; 2-methylimidazoline, 2-ethylimidazoline, 2-isopropylimidazoline, 2-phenylimidazoline, 2-undecylimidazoline 2,4-dimethylimidazoline, imidazolines such as 2-phenyl-4-methylimidazoline; 2,4-diamino-6- [2′-methylimidazolyl- (1 ′)]-ethyl-s-triazine, 2, 4-Diamino-6- [2 ' Azines such as undecylimidazolyl- (1 ′)]-ethyl-s-triazine, 2,4-diamino-6- [2′-ethyl-4′-methylimidazolyl- (1 ′)]-ethyl-s-triazine Imidazoles; and the like. These imidazoles may be used alone or in combination of two or more at any ratio.

  The amount (mixing ratio) of these curing accelerators is not particularly limited, and is an amount that can accelerate the reaction between the epoxy resin component and the epoxy curing agent and does not impair the dielectric properties of the cured resin. In general, when the total amount of the (B) epoxy resin component is 100 parts by weight, it is preferably used within the range of 0.01 to 10 parts by weight, preferably 0.1 to 5 parts by weight. More preferably, it is used within the range.

  Among these compounds, 2-ethyl-4-methylimidazole, 2-phenyl-4-methylimidazole, 2,4-diamino-6- [2 ′] are excellent in circuit embedding property, availability, solvent solubility and the like. -Undecylimidazolyl- (1 ')]-ethyl-s-triazine is more preferably used.

<(D-2) Inorganic filler>
The (D-2) inorganic filler is not particularly limited, and for example, fused silica, crystalline silica, alumina or the like can be used alone or in combination. Among these, spherical fused silica has a small adverse effect on the resin flowability, which is the effect of the present invention, and has the effect of reducing the overall coefficient of thermal expansion, and can be preferably used. With respect to the amount of these inorganic fillers added, it is preferable to add 1 to 200 parts by weight, more preferably 30 parts, based on 100 parts by weight of the resin composition containing the components (A), (B) and (C) of the present invention. It is preferable to add ~ 100 parts by weight.

<(D-3) Thermosetting resin component>
The (D-3) thermosetting component is not particularly limited, but specifically, for example, bismaleimide resin, bisallyl nadiimide resin, acrylic resin, methacrylic resin, hydrosilyl cured resin, allyl cured Thermosetting resin such as resin and unsaturated polyester resin; Side chain reactive group type thermosetting having reactive groups such as allyl group, vinyl group, alkoxysilyl group, hydrosilyl group at the side chain or terminal of polymer chain Polymer; etc. can be used. These thermosetting components may be used alone or in combination of two or more at any ratio. By adding these thermosetting components, various properties such as adhesion, heat resistance, and workability can be improved in the resulting thermosetting resin composition and the cured resin after curing.

  The amount (mixing ratio) of the thermosetting component is not particularly limited as long as it is an amount that can exhibit various characteristics improving effects and does not impair the dielectric properties of the cured resin. .

(III) Use of the thermosetting resin composition according to the present invention The thermosetting resin composition according to the present invention can be suitably used for various applications, among which a flexible printed wiring board and a build-up wiring board. The printed wiring board can be suitably used as a material for a printed wiring board or the like. Specifically, it is suitably used as a protective material for protecting a printed wiring board or a patterned circuit on the printed wiring board, an interlayer insulating material for ensuring insulation between layers in a multilayer printed wiring board, or the like. be able to.

<Resin solution>
Although the form in the case of utilizing the thermosetting resin composition concerning this invention is not specifically limited, For example, it can use as a resin solution (varnish). A resin solution (varnish) is a general term for paints made by dissolving a resin or the like in a solvent. The method for preparing the resin solution is not particularly limited, and the thermosetting resin composition according to the present invention may be added to an appropriate solvent and stirred. Alternatively, the components (A) to (D) described above may be dissolved or dispersed in an appropriate solvent to prepare a solution for each component, and these may be mixed. The solution according to component at this time may contain only each component of (A)-(D), and may contain two or more types of components. Moreover, even if it is the same component, when using multiple types of compounds, you may prepare a solution about each. For example, when two types of polyimide resins are used as the (A) polyimide resin component, the respective polyimide resins may be prepared and mixed as a solution.

  The solvent that can be used in the resin solution is not particularly limited as long as it is a solvent that can dissolve the thermosetting resin composition or each of the components (A) to (D). The following solvents are preferable. Specifically, for example, cyclic ethers such as tetrahydrofuran, dioxolane and dioxane; ethers such as chain ethers such as ethylene glycol dimethyl ether, triglyme, diethylene glycol, ethyl cellosolve and methyl cellosolve; and the like are preferably used. In addition, a mixed solvent obtained by mixing these ethers with toluene, xylenes, glycols, N, N-dimethylformamide, N, N-dimethylacetamide, N-methylpyrrolidone, cyclic siloxane, chain siloxane, etc. is also preferably used. Can do. These solvent may use only 1 type and may use it combining 2 or more types by arbitrary ratios.

<Resin sheet>
Moreover, the thermosetting resin composition concerning this invention can be used as a resin sheet by shape | molding in advance into a sheet form. The configuration of the resin sheet is not particularly limited, and specifically, for example, a single-layer sheet composed solely of a thermosetting resin composition, or the above thermosetting resin composition on one or both sides of a film substrate. Examples of the laminate include a two-layer sheet or a three-layer sheet provided with a resin layer, and a multilayer sheet obtained by alternately laminating a resin layer composed of a film base material and a thermosetting resin composition. Therefore, the present invention includes not only a thermosetting resin composition but also a laminate comprising at least one resin layer formed using the thermosetting resin composition.

  The method for molding the resin sheet is not particularly limited. Usually, the resin solution is cast or coated on the surface of the film substrate (support), and then the resin solution is dried to form a film. What is necessary is just to shape | mold. In this resin sheet, the thermosetting resin composition is in a semi-cured state (B stage state). Therefore, if the semi-cured resin sheet is peeled from the support, the single-layer sheet can be obtained. Moreover, if the resin sheet is not peeled off, a two-layer sheet comprising a film substrate and a resin layer of a thermosetting resin composition can be obtained.

  Furthermore, if a resin solution is cast or applied on both surfaces of the film substrate, and then the resin solution is dried, a three-layer sheet comprising the film substrate and the resin layers on both surfaces thereof can be obtained. Moreover, the said multilayer sheet can be manufactured by repeating the process of casting or apply | coating the said resin solution on the surface of the said film base material, and drying a resin solution after that.

  The kind of film base material used as the support is not particularly limited, and a known resin film can be suitably used. Moreover, when manufacturing a single layer sheet, you may use support bodies other than a film base material. Examples of such a support include a drum and an endless belt.

  When the thermosetting resin composition according to the present invention is used as a resin sheet, whether it is used as a single layer sheet or a laminate, the thickness of the resin layer (a layer made of the thermosetting resin composition) is It is not particularly limited. The thickness of the resin layer may be set to an appropriate thickness depending on the purpose of use.

  Furthermore, the thermosetting resin composition according to the present invention may impregnate the resin solution (varnish) in various fibers such as glass cloth, glass mat, aromatic polyamide fiber cloth, and aromatic polyamide fiber mat. it can. A fiber-reinforced resin sheet can be obtained by semi-curing the thermosetting resin composition impregnated in the fibers.

<Metal layer-containing laminate>
Moreover, the laminated body concerning this invention can also obtain the laminated body (metal layer containing laminated body) containing a metal layer, if not a resin film etc. but metals, such as copper and aluminum, are used as the said film base material. The configuration of the metal layer-containing laminate is not particularly limited as long as it is a laminate including one or more resin layers and metal layers each made of a thermosetting resin composition. Moreover, the resin layer may be provided only on one side of the metal layer or on both sides. Furthermore, you may laminate | stack a metal layer and a resin layer alternately.

  As described above, the metal layer-containing laminate can be produced by casting or coating a resin solution on the surface of the metal layer and drying the resin solution, but is not limited thereto. . For example, it can also be manufactured by laminating a metal foil on the surface of the resin layer in a single-layer sheet or a two-layer sheet obtained by the method described above. Moreover, it can also manufacture by forming a metal layer on the surface of the resin layer in a single layer sheet or a 2 layer sheet | seat by methods, such as chemical plating and sputtering.

<Printed wiring board>
The thermosetting resin composition, resin sheet, laminate, and printed wiring board interlayer adhesive material according to the present invention can be preferably used for printed wiring board applications. When producing a printed wiring board using the metal layer-containing laminate according to the present invention, the metal layer-containing laminate according to the present invention is laminated on an inner layer substrate on which a circuit pattern is formed, and between the circuit patterns according to the present invention. After embedding with the thermosetting resin composition, an etching process is performed on the metal layer to form a circuit (pattern circuit) having a desired pattern, and the printed wiring board according to the present invention can be obtained.

  When the printed wiring board according to the present invention is manufactured using the resin sheet according to the present invention, the metal foil, the resin sheet, and the inner layer substrate on which the circuit pattern is formed are sequentially laminated, and the thermosetting of the present invention is performed between the circuit patterns. After embedding with the conductive resin composition, it is possible to obtain a printed wiring board according to the present invention by performing a pattern etching process by a subtractive method to form a desired conductor circuit pattern. In addition, in the inner layer substrate, after etching the metal foil on the entire surface after lamination to obtain the thermosetting resin surface according to the present invention in which the roughened surface of the metal foil is transferred, the electroless surface is electroless It is also possible to obtain a metal layer for a circuit pattern by plating. This method can be preferably applied to a circuit pattern forming method by an additive method, and is particularly preferably performed when fine wiring formation is necessary.

  When a flexible printed wiring board is used for the inner layer substrate, a multilayer flexible wiring board is manufactured, and when a printed wiring board using a glass-epoxy base is used, a multilayer rigid wiring board or a build-up wiring board is used. Will be manufactured. In addition, vias (holes used only for connecting the layers) need to be formed in the multilayer printed wiring board for vertical electrical connection. In the printed wiring board of the present invention, laser, mechanical A via can be formed by a known method such as drilling or punching, and can be made conductive by a known method such as electroless plating, conductive paste, direct plating, or the like.

  The thermosetting resin composition according to the present invention has appropriate fluidity in a semi-cured state. Therefore, by performing thermocompression treatment such as hot press treatment, laminating treatment (thermal laminating treatment), and hot roll laminating treatment, it is possible to satisfactorily embed the space between pattern circuits with a resin (thermosetting resin composition). .

  Although the processing temperature in the said thermocompression bonding process is not specifically limited, It is preferable to exist in the range of 50 degreeC or more and 250 degrees C or less, It is more preferable to exist in the range of 60 degreeC or more and 200 degrees C or less, 80 degreeC More preferably, it is in the range of 180 ° C. or less. When the said processing temperature exceeds 250 degreeC, a thermosetting resin composition will harden | cure at the time of a thermocompression bonding process, and there exists a possibility that favorable lamination | stacking cannot be performed. On the other hand, when the treatment temperature is lower than 50 ° C., the fluidity of the thermosetting resin composition is low, and it becomes difficult to embed a pattern circuit.

  The thermosetting resin composition layer provided on the pattern circuit serves as a protective material for protecting the pattern circuit or an interlayer insulating material in a multilayer printed wiring board. Therefore, it is preferable that the pattern circuit is embedded and then completely cured by performing heat curing or the like. The specific method of heat curing is not particularly limited, and may be performed under conditions that can sufficiently cure the resin layer, that is, the thermosetting resin composition.

  In the case of curing the resin layer (thermosetting resin composition), in order to sufficiently advance the curing reaction of the epoxy resin component (B), after the metal layer and the resin layer are bonded together, post heat treatment is performed. It is preferable to implement. The conditions for the post heat treatment are not particularly limited, but it is preferable to perform the heat treatment for 10 minutes to 3 hours under temperature conditions in the range of 150 ° C. to 200 ° C.

  Thus, the laminated body and printed wiring board concerning this invention are equipped with the resin layer containing the thermosetting resin composition mentioned above. Therefore, the laminated body and the resin layer of the printed wiring board can impart various properties such as adhesion, workability / handleability, heat resistance, resin fluidity, and dielectric properties in a balanced manner. Thereby, it becomes possible to manufacture a high quality laminated body and a printed wiring board suitably. In particular, when the laminate and the printed wiring board have circuits or the like, the electrical reliability of each circuit can be ensured, and a decrease in signal transmission speed and signal loss in each circuit can be suppressed.

  The present invention will be described more specifically based on examples, but the present invention is not limited to this. Those skilled in the art can make various changes, modifications, and alterations without departing from the scope of the present invention. In addition, when using the thermosetting resin composition concerning this invention as a resin sheet, the fluidity | liquidity, lamination property, and the amount of volatile components were evaluated or computed as follows. Further, the dielectric properties, glass transition temperature, mechanical properties, and volume resistance of a cured resin sheet (cured resin) obtained by heating and curing the resin sheet were measured and evaluated as follows.

〔Liquidity〕
Using a shear mode dynamic viscoelasticity measuring device (CVO, manufactured by Bohling), measure the complex viscosity (Pa · s) of the resin sheet before heat curing under the following conditions and measure the melt viscosity from the complex viscosity. did. The melt viscosity of each resin sheet was evaluated at the lowest melt viscosity within a temperature range of 60 ° C. or higher and 200 ° C. or lower.
Measurement frequency: 1Hz
Temperature rising rate: 12 ° C./min Measurement sample: Circular resin sheet having a diameter of 3 mm [Laminating property 1: presence / absence of bubble entrapment]
Glass epoxy substrate FR-4 (product number: MCL-E-67, manufactured by Hitachi Chemical Co., Ltd.) having a circuit formed with a height of 18 μm, a circuit width of 50 μm, and a distance between circuits of 50 μm; copper foil Sandwich the resin sheet (thickness of 50 μm) so as to contact the glossy surface of the circuit formation surface and copper foil (product number: BHY22BT, manufactured by Japan Energy Co., Ltd.) having a thickness of 50 μm and a total thickness of 1.2 mm. A laminate was obtained by heating and pressurizing for 1 hour under conditions of a temperature of 180 ° C. and a pressure of 3 MPa. The copper foil of the obtained laminate was chemically removed with an iron (III) chloride-hydrochloric acid solution. The surface of the exposed resin sheet was visually observed using an optical microscope (50 times magnification), and the presence or absence of bubbles in the circuit was confirmed.

  If no bubble entrapment between the circuits (the part where the resin does not enter between the circuits) is confirmed, the stacking property is passed (○), and if the entrapment of bubbles is confirmed (or thermosetting resin composition) When the product is too fluid), the stackability was evaluated as rejected (x).

[Laminating property 2: surface irregularities]
Moreover, about the same laminated body as the said laminated property 1, the magnitude | size of the surface unevenness | corrugation on a circuit was evaluated using the NewView5030 system by the light wave interference type surface roughness meter ZYGO company.

[Calculation of amount of volatile components in resin sheet]
Using a mass spectrometer (product number: TGA50, manufactured by Shimadzu Corporation), the resin sheet was placed in a sample container, and the change in weight was measured under the following conditions. The weight decreased within the range of 100 ° C. to 300 ° C. was calculated as a ratio to the weight of the resin sheet before the weight change, and was defined as the amount of volatile components.
Measurement temperature range: 15 ° C-350 ° C
Temperature rising rate: 20 ° C./min Measurement atmosphere: Nitrogen, flow rate 50 mL / min Sample container: Aluminum [Dielectric properties]
Using a cavity resonator perturbation method complex dielectric constant evaluation apparatus (trade name, manufactured by Kanto Electronics Application Development Co., Ltd.), the dielectric constant and dielectric loss tangent of the cured resin sheet were measured under the following conditions.
Measurement frequency: 5 GHz
Measurement temperature: 22 ° C to 24 ° C
Measurement humidity: 45% to 55%
Measurement sample: Resin sheet left for 24 hours under the above measurement temperature and humidity conditions [Glass transition temperature]
Using DMS-200 (product number, manufactured by Seiko Denshi Kogyo Co., Ltd.), the measurement length (measurement jig interval) is 20 mm, measurement is performed under the following conditions, and the temperature of tan δ (= ε ′ / ε ″) The peak temperature of the dispersion spectrum was defined as the glass transition temperature (° C.).
Measurement atmosphere: Under dry air atmosphere
Measurement temperature: 20 ° C to 400 ° C
Measurement sample: cured resin sheet slit to 9 mm width and 40 mm length [Mechanical characteristics]
A cured resin sheet was prepared, and mechanical properties (elastic modulus, tensile strength, tensile elongation) were measured according to JPCA-BU01-1998 (published by Japan Printed Circuit Industry Association).

[Volume resistivity]
A cured resin sheet was prepared, and volume resistance values at room temperature and 125 ° C. were measured according to JIS C6481.

[Synthesis example of polyimide resin]
In a glass flask having a volume of 2000 ml, 0.95 equivalent of 1,3-bis (3-aminophenoxy) benzene (APB) and 0.05 equivalent of 3,3′-dihydroxy-4,4 in dimethylformamide (DMF). '-Diaminobiphenyl (manufactured by Wakayama Seika Kogyo Co., Ltd.) was charged and stirred to dissolve in a nitrogen atmosphere to obtain a DMF solution. Subsequently, the inside of the flask was placed under a nitrogen atmosphere, and the DMF solution was stirred while being cooled with ice water, and 1 equivalent of 4,4 ′-(4,4′-isopropylidenediphenoxy) bisphthalic anhydride (IPBP, GE) was added. Then, the polyamic acid solution was obtained by further stirring for 3 hours. In addition, the usage-amount of the said DMF was set so that the preparation density | concentration of the monomer of APB, 3,3'- dihydroxy-4,4'-diaminobiphenyl and IPBP might be 30 weight%.

  By transferring 300 g of the polyamic acid solution to a vat coated with a fluororesin and heating in a vacuum oven under reduced pressure for 3 hours under the conditions of 200 ° C. and 5 mmHg (about 0.007 atm, about 5.65 hPa). A polyimide resin was obtained.

[Example 1]
Each component shown below was dissolved in dioxolane so as to have a mixing ratio shown in Table 1 to obtain a resin solution (varnish) as a thermosetting resin composition according to the present invention.
(A) Polyimide resin component: polyimide resin obtained by the above synthesis example (B) Epoxy resin component: polyfunctional epoxy resin (trade name: Epicoat 1032H60, ICI viscosity 0.3 Pa · s, epoxy value = 194 g / eq, Japan epoxy Resin Co., Ltd.)
(C) Epoxy curing agent component: 4,4′-diaminodiphenyl sulfone (DDS, molecular weight = 248, manufactured by Wakayama Seika Kogyo Co., Ltd.)
The obtained resin solution was cast on the surface of a 125 μm-thick PET film (trade name Therapy HP, manufactured by Toyo Metallizing Co., Ltd.) as a support. Then, it heat-dried for 3 minutes each at the temperature of 60 degreeC, 80 degreeC, 100 degreeC, 120 degreeC, and 140 degreeC with a hot air oven, and obtained the 2 layer sheet | seat which uses a PET film as a film base material. A single-layer sheet (resin sheet before heat curing) was obtained by peeling and removing the PET film from the two-layer sheet. The thickness of the obtained resin sheet was 50 μm. The resin fluidity, lamination property, and volatile component amount of the obtained resin sheet were evaluated. The results are shown in Table 2.

  Next, using 18 μm rolled copper foil (trade name: BHY-22B-T, manufactured by Japan Energy Co., Ltd.), the resin sheet was sandwiched so as to be in contact with the roughened copper foil surface of the rolled copper foil. . Then, the copper foil laminated body (metal layer containing laminated body) of the structure which pinched | interposed the resin sheet with the rolled copper foil was obtained by heat-pressing for 1 hour on conditions of temperature 180 degreeC and pressure 3MPa. The copper foil of the obtained copper foil laminate was removed by etching to obtain a cured resin sheet. The obtained cured resin sheet was measured for dielectric properties, glass transition temperature, mechanical properties, and volume resistance. The results are shown in Table 2.

[Examples 2 to 5]
A resin sheet (before heat curing) and a cured resin sheet obtained by curing the resin sheet in the same manner as in Example 1 except that the components (A) to (D) are mixed in the ratios shown in Table 1. Got.

  About the obtained resin sheet, fluidity | liquidity, lamination | stacking property, and the amount of volatile components were evaluated, and the dielectric property, glass transition temperature, mechanical property, and volume resistance were evaluated about the cured resin sheet. The results are shown in Table 2.

  In Table 1 and / or Table 3 below, trade name: Ultem is a polyimide resin made by Nippon GE Plastics, and trade name: 1032H60 is a polyfunctional epoxy resin made by Japan Epoxy Resins Co., Ltd. Product name: N660 is a cresol novolac resin manufactured by Dainippon Ink, Ltd. Product name: YX4000H is a biphenyl type epoxy resin manufactured by Japan Epoxy Resin Co., Ltd., Product name: N680 is Dainippon Ink It is a cresol novolac type epoxy resin manufactured by Co., Ltd., DDS is an abbreviation for 4,4′-diaminodiphenylsulfone (manufactured by Wakayama Seika Kogyo Co., Ltd.), and BAPS-M is bis [4- (3-amino Phenoxy) phenyl] sulfone (Wakayama Seika Kogyo Co., Ltd.) is the abbreviation for the product name: C11Z-A is Shikoku Kasei Kogyo. Ltd.) of 2,4-diamino-6- [2'-undecyl-imidazolylmethyl - (1 ')] - ethyl -s- triazine.

[Comparative Examples 1-3]
A resin sheet (before heat curing) and a cured resin sheet obtained by curing the resin sheet in the same manner as in Example 1 except that the components (A) to (D) were mixed in the ratios shown in Table 3. Got. About the obtained resin sheet, fluidity | liquidity, lamination property, and the amount of volatile components were evaluated, and the dielectric characteristic and the glass transition temperature were evaluated about the cured resin sheet. The results are shown in Table 4.

  As is clear from the above results, the thermosetting resin composition according to the present invention includes (A) a polyimide resin component, (B) an epoxy resin component, and (C) an epoxy curing agent component, and the thermosetting resin. The epoxy group contained in the curable resin composition and the total number of moles of the hydroxyl group generated by the ring-opening reaction are blended so as to be 0.2 mol / 100 g or less, and contained in the thermosetting resin composition. By setting the ICI viscosity at 150 ° C. of the at least one epoxy resin of the at least one epoxy resin (B) to be 0.5 Pa · s or less, (i) adhesiveness, (ii) workability and handleability, It can be seen that various characteristics such as (iii) heat resistance, (iv) resin fluidity, and (v) dielectric characteristics can be realized in a sufficient and balanced manner.

  Note that the present invention is not limited to the configurations described above, and various modifications are possible within the scope of the claims, and technical means disclosed in different embodiments and examples respectively. Embodiments obtained by appropriate combinations are also included in the technical scope of the present invention.

  As described above, the thermosetting resin composition according to the present invention has sufficient (i) adhesiveness, (ii) workability and handleability, (iii) heat resistance, and (iv) resin flowability. In addition, (v) the cured resin after curing exhibits a low dielectric constant and a low dielectric loss tangent even in the GHz band, and can exhibit sufficient dielectric properties. Therefore, it can use suitably for manufacture of printed wiring boards, such as a flexible printed wiring board and a buildup wiring board. Therefore, the present invention can be suitably used not only in the material processing industry such as resin compositions and adhesives and various chemical industries, but also in the industrial field of various electronic components.

Claims (12)

A thermosetting resin composition comprising (A) a polyimide resin component, (B) an epoxy resin component, and (C) an epoxy curing agent component,
Each of the above components is blended so that the total number of moles of the epoxy group contained in the thermosetting resin composition and the hydroxyl group generated by the ring-opening reaction is 0.2 mol / 100 g or less,
Furthermore, the thermosetting resin composition characterized in that the epoxy resin component (B) contains at least a low-viscosity epoxy resin having an ICI viscosity at 150 ° C. of 0.5 Pa · s or less.   The minimum melt viscosity is in the range of 10 Pa · s to 10,000 Pa · s in a semi-cured state and the temperature is in the range of 60 ° C. or higher and 200 ° C. or lower. The thermosetting resin composition according to 1.   The thermosetting resin composition according to claim 1 or 2, wherein the dielectric loss tangent in the GHz band after curing is 0.025 or less.   The thermosetting resin composition according to any one of claims 1 to 3, wherein a tensile strength after curing is 50 MPa or more.   The thermosetting resin composition according to any one of claims 1 to 4, wherein the tensile elongation after curing is 3% or more.   6. The thermosetting resin composition according to claim 1, wherein the volume resistance at room temperature after curing is 10E + 15 Ω · cm or more.   The thermosetting resin composition according to any one of claims 1 to 6, wherein the volume resistance at 125 ° C after curing is 10E + 14Ω · cm or more. The at least one polyimide resin contained in the (A) polyimide resin component is represented by the general formula (1).

(Wherein, X ¹ is selected from the group consisting of —O—, —CO—, —O—X ² —O—, —COO—X ² —OCO—, —C (CF ₃ ) ₂ —. A divalent group selected, and X ² represents a divalent organic group)
(A-1) an acid dianhydride component comprising at least one acid dianhydride having a structure represented by:
The thermosetting resin composition according to any one of claims 1 to 7, wherein the thermosetting resin composition is obtained by reacting (A-2) a diamine component comprising at least one diamine. Stuff.   The resin sheet which consists of a thermosetting resin composition of any one of Claim 1 thru | or 8.   A laminate comprising at least one resin layer formed of the thermosetting resin composition according to any one of claims 1 to 9.   The interlayer adhesive material for printed wiring boards which consists of a thermosetting resin composition of any one of Claim 1 thru | or 10, a resin sheet, or a laminated body.   A printed wiring board comprising the thermosetting resin composition according to any one of claims 1 to 11, a resin sheet, a laminate, and an interlayer adhesive material for a printed wiring board.