Resin composition and method for producing the same, as well as adhesive film and interlayer bonding sheet.

Abstract

Provided is a resin composition for adhesive films which has a low dielectric loss and nevertheless attains a sufficient adhesion strength and which can give adhesive films inhibited from suffering resin flow. The resin composition comprises (A) a styrene / butadiene / butylene / styrene block copolymer, (B) an epoxy resin, and (C) a thermosetting resin which is not an epoxy resin, wherein the (A) component has a styrene content of 31-60%.

Description

[Technical Field]

[0001] This invention relates to a resin composition and a method for producing the same, as well as an adhesive film and a layer-indirect bonding sheet. [Background technology]

[0002] In recent years, technological innovations in high-speed, high-capacity communication have advanced in the information and communication field, and the use of the high-frequency range, which enables high-capacity communication, has been increasing. On the other hand, high-frequency signals are prone to attenuation, and antennas and their surrounding flexible circuit boards (hereinafter also called "FPCs") and high-frequency cables (hereinafter also called "RF cables") are required to be designed to have less loss in the high-frequency range. "FPC" is an abbreviation for "Flexible printed circuit," and "RF" is an abbreviation for "Radio Frequency."

[0003] There is a growing demand for core materials with lower dielectric properties used in FPCs, and the use of liquid crystal polymers (hereinafter also referred to as "LCP"), which have lower dielectric properties and better moisture resistance, is increasing compared to conventional polyimide (PI). "LPC" is an abbreviation for "Liquid Crystal Polymer".

[0004] For example, thermosetting resin compositions using specific vinyl compounds and rubber or thermoplastic elastomers, and uncured films made therefrom, have been proposed as materials for use in FPCs and RF cables (see, for example, Patent Document 1). The technology described in Patent Document 1 aims to achieve low elasticity and low dielectric constant and low dielectric loss tangent in the high-frequency range. [Prior art documents] [Patent Documents]

[0005] [Patent Document 1] International Publication No. 2008 / 018483 [Overview of the Initiative] [Problems that the invention aims to solve]

[0006] Currently, FPCs made by laminating LCPs are in practical use, but bonding LCPs sometimes requires high-temperature pressing. Therefore, research is underway on methods to bond LCPs using low-dielectric bonding sheets (e.g., uncured films) that can be pressed at low temperatures.

[0007] Here, the technology described in Patent Document 1, as mentioned above, aims to achieve low elasticity and low dielectric constant / low dielectric loss tangent in the high-frequency range, but it did not take into consideration the resin flow (e.g., fluidity) of the film. Hereafter, the resin flow (fluidity) of the film as described above may be referred to as "resin flow".

[0008] Traditionally, films with high resin flow rates have been used for FPCs, for example, to facilitate wiring embedding. However, in recent years, multilayer substrates, such as those used in the manufacturing of high-frequency circuit boards, are sometimes constructed by drilling holes. Using a highly fluid film on such a drilled and multilayer substrate can cause the film to clog the holes in the substrate, leading to defects. Therefore, it is necessary to suppress resin flow in multilayer substrates that undergo press curing after drilling, and the development of a film capable of suppressing resin flow has been highly desired.

[0009] Furthermore, in the field of electrical and electronic equipment, dielectric properties such as low dielectric constant and low dielectric loss tangent are required for use in high-frequency ranges. In addition, high adhesion to materials such as LCP is required for bonding sheets for multilayer substrates. The material described in Patent Document 1 above had room for improvement in terms of dielectric loss tangent and adhesion strength to LCP as described above.

[0010] This invention has been made in view of the problems of the prior art. The present invention provides a resin composition for adhesive films that can achieve sufficient adhesive strength while having low dielectric loss and can suppress resin flow of the adhesive film, as well as an adhesive film and a layer-indirect bonding sheet. [Means for solving the problem]

[0011] According to the present invention, the following resin compositions and methods for producing the same, as well as adhesive films and interlayer bonding sheets, are provided.

[0012] [1] (A) Styrene / butadiene / butylene / styrene block copolymer and (B) Epoxy resin and (C) Thermosetting resins other than epoxy resins, (E) Organic peroxides and Includes, The styrene ratio of component (A) is 31-60%, The weight-average molecular weight of component (A) is 30,000 to 300,000. The above (C) component is a thermosetting resin with a dielectric constant of 3.0 or less in the frequency range of 10 GHz. the law of nature, The aforementioned component (A) is a hydrogenated styrene-based thermoplastic elastomer in which some of the double bonds are selectively hydrogenated. The aforementioned component (C) has a carbon-carbon double bond at its terminal end. A resin composition.

[0013] [2] The above (A) component is, (A1) A first styrene / butadiene / butylene / styrene block copolymer with a styrene ratio of 40% or more, (A2) A second styrene / butadiene / butylene / styrene block copolymer with a styrene ratio of less than 40%, The resin composition according to [1] above, comprising:

[0014] [3] The resin composition according to [1] or [2], wherein the (C) component is a thermosetting resin having a dielectric loss tangent of 0.004 or less in the 10 GHz frequency range. [4] The resin composition according to [1] or [2], wherein the styrene ratio of component (A) is 33 to 46%. [ 5The resin composition according to [1] or [2], wherein the component (C) is a terminally modified polyphenylene ether resin.

[0015] 6 The resin composition, wherein the component (C) is a modified polyphenylene ether resin having a carbon-carbon double bond at the terminal. The above [1] or [2] as described above.

[0016] 7 The resin composition, wherein the content ratio of the component (C) to the component (A) is 10:90 to 40:60 by mass ratio, (C) component:(A) component = 10:90~40:60. The above [1] or [2] as described above.

[0017] 8 The resin composition, wherein the component (B) is contained in an amount of 0.1 to 3% by mass based on 100% by mass of the resin components in the resin composition. The above [1] or [2] as described above.

[0018] 9 The resin composition further containing a (D) curing catalyst. The above [1] or [2] as described above.

[0020] 10 The above [1] or [2] An adhesive film using the resin composition as described above.

[0021] 11 The above [1] or [2] An interlayer adhesion bonding sheet using the resin composition as described above.

[0022] 12 The above [1] or [2] A cured product comprising the resin composition as described above.

[0023] 13 The 10 A cured product comprising the adhesive film as described above. <000013​​​​​​​​​​​​​​​​​​

[0025] [ 15 ] The above [ 14 A cured product consisting of the laminates described in [ ].

[0026] [ 16 ] The above [1] or [2] A laminate using the resin composition described above.

[0027] [ 17 ] The above [1] or [2] A semiconductor device using the resin composition described above.

[0028]

[18] The process comprises mixing (A) styrene / butadiene / butylene / styrene block copolymer, (B) epoxy resin, and (C) thermosetting resin other than epoxy resin. As component (A), at least (A1) a first styrene / butadiene / butylene / styrene block copolymer having a styrene ratio of 40% or more, and (A2) a second styrene / butadiene / butylene / styrene block copolymer having a styrene ratio of 40% or less, The mixing ratio of component (A1) and component (A2) is adjusted so that the styrene ratio of component (A) is 31-60%. death, As component (C), a thermosetting resin with a dielectric constant of 3.0 or less in the 10 GHz frequency range and having carbon-carbon double bonds at its ends is used. As component (A), a hydrogenated styrene-based thermoplastic elastomer in which a portion of the double bonds is selectively hydrogenated is used. A method for producing a resin composition. [Effects of the Invention]

[0029] The resin composition of the present invention can be suitably used as a resin composition for adhesive films, and in particular, it has the effect of providing sufficient adhesive strength while having low dielectric loss and suppressing resin flow in adhesive films. In particular, when the resin composition of the present invention is used as a bonding sheet for multilayer substrates, it can suppress resin flow in the perforated areas when the substrate is multilayered. Furthermore, the manufacturing method of the resin composition of the present invention allows for the simple production of the above-described resin composition.

[0030] Furthermore, the adhesive film and interlayer bonding sheet of the present invention utilize the above-mentioned resin composition, achieve sufficient adhesive strength while exhibiting low dielectric loss, and in particular, have the effect of suppressing resin flow in the perforated areas when the substrate is multilayered. [Brief explanation of the drawing]

[0031] [Figure 1] This is a schematic diagram illustrating the method for measuring flow rate. [Figure 2] This is a schematic diagram illustrating the method for measuring flow rate. [Figure 3] This is a schematic diagram illustrating the method for measuring flow rate. [Modes for carrying out the invention]

[0032] The embodiments of the present invention will be described below, but the present invention is not limited to the embodiments described below. Therefore, it should be understood that any modifications, improvements, etc., made to the embodiments described below, based on the ordinary knowledge of those skilled in the art, without departing from the spirit of the present invention, also fall within the scope of the present invention.

[0033] (1) Resin composition: One embodiment of the resin composition of the present invention is a resin composition comprising (A) styrene / butadiene / butylene / styrene block copolymer (hereinafter also referred to as "component (A)"), (B) epoxy resin (hereinafter also referred to as "component (B)"), and (C) a thermosetting resin other than epoxy resin (hereinafter also referred to as "component (C)"). In this embodiment, the styrene ratio of component (A) in the resin composition is 31 to 60%. The resin composition configured as described above can be suitably used as a resin composition for adhesive films, and in particular, it can provide sufficient adhesive strength while having low dielectric loss, and can suppress resin flow in the perforated areas when multilayering substrates.

[0034] In addition to components (A), (B), and (C) described above, the resin composition of this embodiment may also contain other components such as (D) a curing catalyst and (E) an organic peroxide.

[0035] (Component A) (A) Component is a styrene / butadiene / butylene / styrene block copolymer with a styrene ratio of 31-60%. Hereafter, styrene / butadiene / butylene / styrene block copolymer may be referred to as "SBBS".

[0036] (A) Component styrene / butadiene / butylene / styrene block copolymer (SBBS) is a hydrogenated styrene-based thermoplastic elastomer obtained by highly selectively hydrogenating the 1,2-bonds in the polybutadiene block of styrene / butadiene / styrene block copolymer (hereinafter also referred to as "SBS"). By including SBBS as component (A), solder heat resistance and dielectric properties can be improved. The presence or absence of component (A) in the resin composition can be detected by methods such as Fourier transform infrared spectrophotometer (FTIR).

[0037] In this embodiment, the styrene / butadiene / butylene / styrene block copolymer as component (A) does not include styrene / ethylene / butylene / styrene block copolymer (hereinafter also referred to as "SEBS"), in which all double bonds in the polybutadiene block are hydrogenated. Hereinafter, styrene-based thermoplastic elastomers in which all double bonds are hydrogenated will be referred to as "hydrogenated styrene-based thermoplastic elastomers," and hydrogenated styrene-based thermoplastic elastomers in which some of the double bonds, such as component (A), are selectively hydrogenated will be referred to as "partially hydrogenated styrene-based thermoplastic elastomers." Furthermore, styrene-based thermoplastic elastomers that have not undergone hydrogenation, such as styrene / butadiene / styrene block copolymer (hereinafter also referred to as "SBS"), will be referred to as "unhydrogenated styrene-based thermoplastic elastomers."

[0038] The resin composition of this embodiment has a particularly important feature in that its styrene ratio is 31-60%. By having a styrene ratio of 31-60% in component (A), it is possible to achieve low resin flow and sufficient adhesive strength to LCP. Here, for example, if the styrene ratio of component (A) is less than 31%, the adhesive strength is strong, but the control of resin flow cannot be said to be sufficient. On the other hand, as the styrene ratio of component (A) increases, resin flow can be suppressed, but the adhesive strength weakens, and if the styrene ratio exceeds 60%, it becomes difficult to form a film of the resin composition. Although not particularly limited, in order to obtain low resin flow and sufficient adhesive strength to LCP, the styrene ratio of component (A) is preferably 32-52%, and more preferably 33-46%.

[0039] Here, "styrene ratio" refers to the percentage (%) of the styrene content relative to the total mass of the styrene-based thermoplastic elastomer. For example, the styrene ratio is measured using nuclear magnetic resonance (NMR). Specifically, tetrachloroethane is used as the solvent, and the integral values ​​of the peaks in the range of 5.5 ppm to 6.5 ppm, which corresponds to styrene, and the integral values ​​of the peaks in other ranges are determined, and the ratio is calculated from the obtained values.

[0040] If component (A) consists of only one type of SBBS, the styrene ratio of that SBBS becomes the "styrene ratio of component (A)". If component (A) is a mixture of two or more types of SBBS with different styrene ratios, the weighted average of the styrene ratios of those SBBS becomes the "styrene ratio of component (A)". Thus, when component (A) is a mixture of two or more types of SBBS with different styrene ratios, the styrene ratio of that component (A) is sometimes called the "average styrene ratio".

[0041] Here, for example, if component (A) consists of two types of SBBS with different styrene ratios, the average styrene ratio (%) of component (A) can be calculated based on the following formula (1). Here, one of the two types of SBBS is referred to as "SBBS(1)" and the other as "SBBS(2)". Also, in formula (1), "X (1) " indicates the mass ratio (mass%) of SBBS(1) in component (A), and "X (2) " indicates the mass ratio (mass%) of SBBS(2) in component (A). Also, "ST (1) " indicates the styrene ratio (%) of SBBS(1), and "ST (2) " indicates the styrene ratio (%) of SBBS(2).

[0042]

number

[0043] For example, suppose the styrene ratio of SBBS(1) is 20% and the styrene ratio of SBBS(2) is 40%. If the mass ratio of SBBS(1) in component (A) is 10% by mass and the mass ratio of SBBS(2) is 90% by mass, then the average styrene ratio of component (A) can be calculated using the formula shown in equation (2) below. That is, the average styrene ratio of such component (A) is 38%. If three or more different types of SBBS are mixed, the weighted average value of the styrene ratios of the three or more types of SBBS should be calculated following the formula in equation (1) above.

[0044]

number

[0045] (A) If component (A) is a mixture of two or more SBBS with different styrene ratios, the resin flow can be appropriately controlled and sufficient adhesive strength to LCP can be obtained. For example, component (A) is preferably composed as follows: Component (A) preferably contains (A1) a first styrene / butadiene / butylene / styrene block copolymer with a styrene ratio of 40% or more, and (A2) a second styrene / butadiene / butylene / styrene block copolymer with a styrene ratio of less than 40%. There are no particular restrictions on the mixing ratio (mass ratio) of (A1) the first styrene / butadiene / butylene / styrene block copolymer and (A2) the second styrene / butadiene / butylene / styrene block copolymer; any mixing ratio that results in an average styrene ratio of component (A) containing both falling within the range of 31-60% is acceptable.

[0046] Component (A) has good compatibility with components (B) and (C) and good film-forming ability, and yields a cured product with excellent strength balance. Therefore, its weight-average molecular weight is preferably 30,000 to 300,000, more preferably 40,000 to 100,000, and even more preferably 50,000 to 80,000. The weight-average molecular weight is determined by gel permeation chromatography (GPC) using a calibration curve with standard polystyrene. Component (A) may also be a reactive elastomer to which functional groups such as amines have been added. Using a reactive elastomer to which functional groups have been added can further improve adhesive strength (peel strength).

[0047] There are no particular restrictions on the content of component (A). However, the content ratio of component (C) to component (A) is preferably (C) component:(A) component = 10:90 to 40:60 by mass ratio, and more preferably 15:85 to 35:65. In the above-mentioned content ratio of component (C) to component (A), if the amount of component (C) is too small (in other words, if the amount of component (A) is too large), it is undesirable because the amount of curing component will decrease, and the flow rate will increase. On the other hand, in the above-mentioned content ratio of component (C) to component (A), if the amount of component (C) is too large (in other words, if the amount of component (A) is too small), it is undesirable because the amount of curing component will increase, and the cured film will become hard, resulting in a decrease in adhesiveness.

[0048] Furthermore, component (A) is preferably present in an amount of 60 to 83% by mass, and more preferably in an amount of 65 to 72% by mass, relative to 100% by mass of the resin components in the resin composition.

[0049] (A) A specific example of component (A) is the product name "P5051" manufactured by Asahi Kasei Chemicals. Alternatively, two or more products such as "P1083", "P1500", "P5051", and "P2000" manufactured by Asahi Kasei Chemicals may be used as component (A) in a mixture such that the average styrene ratio is 31-60%.

[0050] ((B) component) Component (B) is an epoxy resin. Examples of epoxy resins for component (B) include bisphenol A type epoxy resin, bisphenol F type epoxy resin, phenol novolac type epoxy resin, alicyclic epoxy resin, siloxane type epoxy resin, biphenyl type epoxy resin, glycidyl ester type epoxy resin, glycidylamine type epoxy resin, hydantoin type epoxy resin, and naphthalene ring-containing epoxy resin. In the epoxy resin composition, the compounds exemplified here may be used individually or in mixtures of two or more. It is preferable that the epoxy resin for component (B) be a solid epoxy resin from the viewpoint of suppressing resin flow. Furthermore, it is preferable that the epoxy resin for component (B) is an epoxy resin having a naphthalene skeleton, as this improves the adhesion of the film formed using the resin composition.

[0051] There are no particular restrictions on the content of component (B). However, component (B) is preferably present in an amount of 0.1 to 3% by mass, and more preferably 0.5 to 1.5% by mass, relative to 100% by mass of the resin component in the resin composition. Including epoxy resin as component (B) can improve adhesive strength. For example, if component (B) is less than 0.1% by mass, it may be difficult to obtain the desired adhesive strength. On the other hand, if there is too much component (B), the dielectric properties may deteriorate.

[0052] (B) Specific examples of component include, for example, bisphenol A type epoxy resin manufactured by Mitsubishi Chemical Corporation, trade name "828EL", and epoxy resin manufactured by Nippon Kayaku Co., Ltd., trade name "502H".

[0053] ((C) component) Component (C) is a thermosetting resin other than epoxy resin. Any thermosetting resin other than epoxy resin can be selected, but a thermosetting resin with a low dielectric constant and dielectric loss tangent is preferred. More specifically, a thermosetting resin with a dielectric constant of preferably 3.0 or less, more preferably 2.5 or less in the 10 GHz frequency range, or a dielectric loss tangent of 0.004 or less, more preferably 0.003 or less in the 10 GHz frequency range is preferred. From this viewpoint, a suitable example of a thermosetting resin other than epoxy resin as component (C) is a terminally modified polyphenylene ether resin.

[0054] Furthermore, among the terminally modified polyphenylene ether resins described above, modified polyphenylene ether resins having carbon-carbon double bonds at the terminals are more preferred. Modified polyphenylene ether resins having carbon-carbon double bonds at the terminals have relatively low polarity and yield a low dielectric loss tangent.

[0055] (C) The thermosetting resin other than epoxy resin as component (C) preferably has a number average molecular weight of 1000 or more, and more preferably has a number average molecular weight of 2000 or more from the viewpoint of suppressing resin flow.

[0056] ((D) component) Component (D) is a curing catalyst. Component (D) is an ingredient that assists in the curing of adhesive films and interlayer bonding sheets formed using the resin composition of this embodiment. In particular, it is preferable that component (D) is a catalyst that promotes the curing reaction of the epoxy resin of component (B).

[0057] Examples of curing catalysts as component (D) include imidazole-based curing catalysts, amine-based curing catalysts, and phosphorus-based curing catalysts. Examples of imidazole-based curing catalysts include imidazole compounds such as 2-methylimidazole, 2-undecylimidazole, 1-cyanoethyl-2-undecylimidazole, 2-heptadecylimidazole, 2-ethyl-4-methylimidazole, 1-cyanoethyl-2-ethyl-4-imidazole, 2-phenylimidazole, 1-benzyl-2-phenylimidazole, and 2-phenyl-4-methylimidazole. Among these, 2-ethyl-4-methylimidazole, 1-cyanoethyl-2-undecylimidazole, and 1-cyanoethyl-2-ethyl-4-imidazole are preferred. Examples of amine-based curing catalysts include triazine compounds such as 2,4-diamino-6-[2'-methylimidazolyl-(1')]ethyl-s-triazine, and tertiary amine compounds such as 1,8-diazabicyclo[5,4,0]undecene-7(DBU), triethylenediamine, benzyldimethylamine, and triethanolamine. Among these, 2,4-diamino-6-[2'-methylimidazolyl-(1')]ethyl-s-triazine is preferred. Examples of phosphorus-based curing catalysts include triphenylphosphine, tributylphosphine, tri(p-methylphenyl)phosphine, and tri(nonylphenyl)phosphine. Among these, imidazole-based curing catalysts are preferred because they can be adjusted to have appropriate curability. Furthermore, imidazole-based curing catalysts having a benzene ring are more preferred because they can increase the adhesive strength of the uncured film formed using the resin composition of this embodiment over time. Examples of such imidazole-based curing catalysts include 2-phenylimidazole, 1-benzyl-2-phenylimidazole, and 2-phenyl-4-methylimidazole, with 1-benzyl-2-phenylimidazole being particularly preferred.

[0058] The content of component (D) can be appropriately selected depending on the type of curing catalyst used as component (D). When an imidazole-based curing catalyst is used as component (D), it is preferably 0.01 to 20 parts by mass, more preferably 0.1 to 15 parts by mass, and even more preferably 1 to 10 parts by mass, per 100 parts by mass of epoxy resin of component (B). If the content of component (D) is too low, the curing performance may deteriorate. On the other hand, if the content of component (D) is too high, the shelf life of the adhesive film may deteriorate.

[0059] ((E) component) Component (E) is an organic peroxide. Examples of organic peroxides of component (E) include t-butyl peroxybenzoate, t-butyl peroxyisopropyl carbonate, t-butyl peroxy-2-ethylhexyl carbonate, t-butyl peroxyacetate, dicumyl peroxide, 2,5-dimethyl-2,5-di(t-butylperoxy)hexane, di-t-butyl peroxide, 2,5-dimethyl-2,5-di(t-butylperoxy)hexine-3, and 1,1-di(t-butylperoxy)-3,3 Examples include 5-trimethylcyclohexane, 1,1-di(t-butylperoxy)cyclohexane, methyl ethyl ketone peroxide, 2,5-dimethylhexyl-2,5-diperoxybenzoate, t-butyl hydroperoxide, p-menthane hydroperoxide, benzoyl peroxide, p-chlorobenzoyl peroxide, t-butyl peroxyisobutyrate, hydroxyheptyl peroxide, and diclohexanone peroxide.

[0060] By adding an organic peroxide of component (E), the curing reaction of component (C), such as a terminally modified polyphenylene ether resin, can be accelerated and its reactivity can be stabilized. Considering that the resin composition of this embodiment will be used in film form, it is preferable that component (E) does not become active in the temperature range of 60 to 120°C during the film drying process, but becomes active at higher temperatures. An example of such a component (E) is t-butyl peroxybenzoate.

[0061] (Other combination drugs) The resin composition of this embodiment may further contain components other than those described above (A) to (E) as necessary. Specific examples of such components include silane coupling agents, defoaming agents, flow regulators, film-forming aids, dispersants, and inorganic particles. The type and amount of each compounding agent are as per conventional methods.

[0062] On the other hand, it is preferable that the resin composition of this embodiment does not contain any components that adversely affect the high-frequency characteristics of the adhesive film formed using it. Examples of such components include liquid rubber and flame retardants.

[0063] (Properties of resin compositions) The resin composition of this embodiment preferably has the following characteristics, for example. The resin composition of this embodiment preferably has excellent electrical properties at high frequencies in its cured product (e.g., thermoset product). Specifically, the cured product of the resin composition preferably has a dielectric constant (ε) of 2.5 or less in the frequency range of 1 to 10 GHz, and more preferably 2.4 or less. Furthermore, the dielectric loss tangent (tanδ) in the frequency range of 1 to 10 GHz is more preferably 0.0025 or less, and more preferably 0.0022 or less. By having the dielectric constant (ε) and dielectric loss tangent (tanδ) in the frequency range of 1 to 10 GHz within the above range, electrical signal loss in the frequency range of 1 to 10 GHz can be reduced.

[0064] In this embodiment, it is preferable that the cured resin composition has sufficient adhesive strength. Specifically, it is preferable that the cured resin composition has a peel strength (180-degree peel) of 4 N / cm or more against a roughened copper foil surface, as measured in accordance with JIS K6854-2. It is also preferable that the peel strength (90-degree peel) against a liquid crystal polymer film, as measured in accordance with JIS K6854-1, is 3 N / cm or more.

[0065] (Method for manufacturing resin compositions) The resin composition of this embodiment can be manufactured by conventional methods. For example, first, components (A) to (C) above are mixed in the presence of a solvent to obtain a mixture. When manufacturing the resin composition of this embodiment, a styrene / butadiene / butylene / styrene block copolymer with a styrene ratio of 31 to 60% is used as component (A). Furthermore, the epoxy resin described above is used as component (B), and a thermosetting resin other than the epoxy resin described above is used as component (C). If the resin composition contains other optional components besides components (A) to (C), these optional components may be added to the mixture described above according to conventional methods as appropriate. The mixing of components (A) to (C) can be carried out, for example, using a heated mixing kneader. There are no particular restrictions on the mixing conditions; for example, a rotation speed of 100 to 1000 rpm, 80°C, and 3 hours can be used.

[0066] When manufacturing the resin composition of this embodiment, it is preferable to use at least (A1) a first styrene / butadiene / butylene / styrene block copolymer with a styrene ratio of 40% or more and (A2) a second styrene / butadiene / butylene / styrene block copolymer with a styrene ratio of less than 40% as component (A), and to adjust the blending ratio of components (A1) and (A2) as described above so that the average styrene ratio of component (A) is 31 to 60%. By configuring it in this way, the styrene ratio (average styrene ratio) of component (A) can be adjusted to a desired value. For example, commercially available styrene / butadiene / butylene / styrene block copolymer can be used as component (A), but since the styrene ratio of commercially available products is determined by the specifications of the thermoplastic elastomer, it is difficult to adjust the styrene ratio of such styrene / butadiene / butylene / styrene block copolymer to a desired value. Therefore, by using the method described above, namely by mixing component (A1) with a styrene ratio of 40% or more and component (A2) with a styrene ratio of less than 40%, it becomes possible to finely adjust the styrene ratio of component (A).

[0067] Next, after the resulting mixture is cooled, components (D) and (E) are added as needed, and the mixture is stirred at room temperature for, for example, 30 to 60 minutes. In this way, the resin composition of this embodiment can be produced.

[0068] (2) Adhesive films and interlayer bonding sheets: Next, embodiments of the adhesive film and interlayer bonding sheet of the present invention will be described. The adhesive film of this embodiment is an adhesive film using the resin composition of this embodiment described above. The adhesive film of this embodiment has low dielectric loss while providing sufficient adhesive strength, and in particular, it can suppress resin flow in the perforated areas when the substrate is multilayered. The adhesive film of this embodiment can be obtained from the resin composition of this embodiment by known methods. For example, the resin composition of this embodiment can be diluted with a solvent to make a varnish, which can be applied to at least one side of a support, dried, and then provided as a film attached to a support or a film peeled off from a support.

[0069] Suitable solvents for use as varnish include ketones such as methyl ethyl ketone and methyl isobutyl ketone; aromatic solvents such as toluene and xylene; and high-boiling point solvents such as dioctyl phthalate and dibutyl phthalate. The amount of solvent used is not particularly limited and can be the amount conventionally used, but preferably it is 20 to 90% by mass relative to the solid content.

[0070] The support is appropriately selected according to the desired form in the method for manufacturing the adhesive film and is not particularly limited, but examples include metal foil such as copper or aluminum, and resin carrier films such as polyester or polyethylene. When the adhesive film is provided in the form of an adhesive film peeled from the support, it is preferable that the support is released with a silicone compound or the like.

[0071] The method of applying the varnish is not particularly limited, but examples include the slot die method, gravure method, doctor coater method, etc., and is appropriately selected according to the desired film thickness, but the gravure method is particularly preferred because it allows for the design of a thin film. The application is carried out so that the thickness of the film formed after drying is the desired thickness. Such a thickness can be derived from the solvent content by those skilled in the art.

[0072] The thickness of the adhesive film is designed appropriately based on the properties such as mechanical strength required for the application, but is generally 1 to 100 μm, and preferably 1 to 30 μm when thin film thickness is required.

[0073] The drying conditions are designed appropriately according to the type and amount of solvent used in the varnish, the amount of varnish used, and the thickness of the application, and are not particularly limited, but for example, they can be set at 60-100°C and carried out under atmospheric pressure.

[0074] The interlayer bonding sheet of this embodiment, like the adhesive film described above, is an interlayer bonding sheet for multilayer substrates using the resin composition of this embodiment. Therefore, sufficient adhesive strength can be obtained while maintaining low dielectric loss, and in particular, resin flow in the perforated areas can be suppressed when multilayering the substrate.

[0075] When using the adhesive film of this embodiment as an adhesive film for electrical and electronic applications, the procedure for use is as follows: Place the adhesive film on the surface to be bonded of one of the objects to be bonded, and then place the other object so that its surface to be bonded is in contact with the exposed surface of the adhesive film of this embodiment. When using the adhesive film of this embodiment with a support, place the adhesive film so that its exposed surface is in contact with the surface to be bonded of one of the objects, and temporarily press the adhesive film onto the bonded surface. The temperature during temporary pressing can be, for example, 130°C.

[0076] Next, after the initial bonding, the support is peeled off to expose the adhesive film, onto which the other object is placed so that its bonded surface is in contact with the exposed surface of the adhesive film. After these steps are performed, the object is heat-pressed at a predetermined temperature and for a predetermined time, and then heat-cured. Note that the heat-pressing step may be omitted.

[0077] The temperature during heat bonding is preferably 100 to 150°C. The heat bonding time is preferably 0.5 to 10 minutes. The heat curing temperature is preferably 150 to 200°C. The heat curing time is preferably 30 to 120 minutes. Alternatively, instead of using a pre-formed film, the resin composition of this embodiment may be diluted with a solvent to form a varnish, which may be applied to the bonding surface of one of the objects to be bonded, dried, and then the object to be bonded may be placed on top of it.

[0078] When using the adhesive film of this embodiment as a coverlay film, the procedure for use is as follows: Place the adhesive film of this embodiment at a predetermined position on a wired resin substrate with a wiring pattern formed on its main surface, that is, on the side with the wiring pattern, where the adhesive film will be covered. Then, pre-press, heat-press, and heat-cur the film at a predetermined temperature and time. Note that the heat-press step may be omitted. The temperature and time for pre-press, heat-press, and heat-curing are the same as when used as an adhesive film for electrical and electronic applications.

[0079] The interlayer bonding sheet of this embodiment is suitable as an interlayer bonding sheet for multilayer substrates and can be used, for example, for interlayer bonding between substrates of a semiconductor device. In this case, the objects to be bonded, as described in the adhesive film section above, are multiple substrates that are stacked in multiple layers and constitute a semiconductor device. For interlayer bonding between substrates of a semiconductor device, instead of using a pre-formed film, a varnish obtained by diluting the resin composition of this embodiment with a solvent may be used.

[0080] There are no particular restrictions on the substrates that make up the semiconductor device; for example, organic substrates such as epoxy resin, phenolic resin, and bismaleimidotriazine resin, or inorganic substrates such as CCL substrates, ceramic substrates, and silicon substrates can all be used. For example, a laminate in which components containing liquid crystal polymers are laminated using the interlayer bonding sheet of this embodiment can be cited as a suitable example.

[0081] Furthermore, the resin composition, adhesive film, and interlayer bonding sheet described above can also be provided as cured products obtained by curing them. For example, a cured product made from the resin composition of this embodiment, a cured product made from the adhesive film of this embodiment, and a cured product made from the interlayer bonding sheet can be provided. Furthermore, a cured product made from a laminate in which a member containing a liquid crystal polymer using the interlayer bonding sheet is laminated can also be provided.

[0082] Furthermore, the present invention can also provide laminates using the resin compositions described above, and semiconductor devices using the resin compositions. In particular, the resin compositions of this embodiment have low dielectric loss while providing sufficient adhesive strength, and can suppress resin flow in the perforated areas when the substrate is multilayered. [Examples]

[0083] The present invention will be described in more detail below with reference to examples, but the present invention is not limited in any way by these examples. In the following examples, parts and % refer to parts by mass and mass% unless otherwise specified.

[0084] (Examples 1-14, Comparative Examples 1-5) [Sample preparation] Each component was weighed and mixed according to the proportions (mass%) shown in Tables 1 to 4 below. These mixtures were then placed in a reaction vessel heated to 80°C and mixed under atmospheric pressure for 4 hours while rotating at 150 rpm. However, the curing catalyst (component D) and the organic peroxide (component E) were added after cooling. In this manner, varnishes containing the resin compositions of Examples 1 to 14 and Comparative Examples 1 to 5 were prepared.

[0085] [Component (A)] (A-1): Partially hydrogenated styrene-based thermoplastic elastomer (SBBS(1)), manufactured by Asahi Kasei Chemicals, trade name "P1083". (A-2): Partially hydrogenated styrene-based thermoplastic elastomer (SBBS(2)), manufactured by Asahi Kasei Chemicals, product name "P1500". (A-3): Partially hydrogenated styrene-based thermoplastic elastomer (SBBS(3)), manufactured by Asahi Kasei Chemicals, product name "P5051". (A-4): Partially hydrogenated styrene-based thermoplastic elastomer (SBBS(4)), manufactured by Asahi Kasei Chemicals, product name "P2000". [Component (A')] (A'-5): Non-hydrogenated styrene thermoplastic elastomer (SBS(1)), manufactured by JSR Corporation, product name "TR2003". (A'-6): Hydrogenated styrene-based thermoplastic elastomer (SEBS(1)), manufactured by Asahi Kasei Chemicals, trade name "H1517". [(B) component] (B-1): Epoxy resin, manufactured by Nippon Kayaku Co., Ltd., product name "EPPN-502H". (B-2): Epoxy resin, manufactured by Mitsubishi Chemical Corporation, product name "828EL". [(C) component] (C-1): Thermosetting resin other than epoxy resin, manufactured by Mitsubishi Gas Chemical Company, product name "OPE-1200". (C-2): Thermosetting resin other than epoxy resin, manufactured by Mitsubishi Gas Chemical Company, product name "OPE-2200". [(D) component] (D-1): Curing catalyst, imidazole manufactured by Adeka Corporation, trade name "EH2021". (D-2): Curing catalyst, 2-ethyl-4-methylimidazole manufactured by Shikoku Chemicals Co., Ltd., trade name "2E4MZ". [(E) component] (E-1): Organic peroxide, manufactured by NOF Corporation, product name "Perbutyl Z". (E-2): Organic peroxide, manufactured by NOF Corporation, product name "Parkmill D". [Other compounding agents] (Inorganic particles-1): Fused silica, manufactured by Denka Co., Ltd., product name "FB-300MDX". (Inorganic particles-2): Fused silica, manufactured by Denka Co., Ltd., product name "FB-300MDX (low dielectric loss tangent treatment)".

[0086] In Examples 1-11, 13, 14 and Comparative Example 3, resin compositions were prepared using two elastomers from (A-1) to (A-4) as component (A). In particular, in Examples 1-11, 13, and 14, the amounts of the two elastomers were adjusted so that the average styrene ratio of component (A) fell within the range of 33-46%. The "Elastomer Content Ratio of Component (A) and Component (A')" column in Tables 1-4 shows the content ratio (%) of component (A) and component (A') relative to the total of component (A) to (D) (100.00%). The "Ratio of First Elastomer" and "Ratio of Second Elastomer" columns in Tables 1-4 show the blending ratio (%) of the two elastomers used as component (A) and component (A'). If only one of the components (A) and (A') is used, "100.00%" should be written in the "Ratio of the First Elastomer" column. The "Average Styrene Ratio" column in Tables 1 to 4 shows the styrene ratio of the components (A) and (A') used in each example and comparative example. In addition, in Examples 13 and 14, fused silica as shown in Table 3 was further added as another compounding agent to prepare the resin composition.

[0087] Next, a varnish containing the obtained resin composition was applied to one side of a support (a PET film that had been treated for mold release) and dried at 100°C to obtain an adhesive film with a support.

[0088] Next, a PET film treated with a release agent was placed on the adhesive film with a support prepared in each example and comparative example to obtain a PET film / adhesive film / PET film laminate. This film laminate was pressed at a press temperature of 200°C, a temperature holding time of 75 minutes, and a press pressure of 0.44 MPa (45 kgf / cm²). 2 The adhesive film was heat-cured by hot pressing under the specified heating and pressurizing conditions. After the PET film, which had been treated with a release agent, was removed from both sides of the cured adhesive film, the following evaluations were performed. The results of each evaluation are shown in Tables 1 to 4.

[0089] [Dielectric constant (ε), dielectric loss tangent (tanδ)] The adhesive film was heated at 200°C for 75 minutes at 0.44 MPa (45 kgf / cm²).2 The adhesive film was heat-cured and peeled off the support. A test piece (50±0.5mm × 100±2mm) was then cut from the adhesive film and its thickness was measured. The dielectric constant (ε) and dielectric loss tangent (tanδ) of the film whose thickness was measured were measured using the dielectric resonator method (SPDR method). The measurement frequency for the dielectric resonator method was set to 10 GHz. The dielectric constant (ε) is preferably 3.0 or less, and more preferably 2.5 or less. The dielectric loss tangent (tanδ) is preferably 0.0025 or less, and more preferably 0.0020 or less.

[0090] [Adhesive peel strength (copper foil)] Copper foil was bonded to both sides of the adhesive film with the roughened side facing inward, and then heat-pressed using a press machine. The heat-pressing conditions were 200°C, 75 minutes, and 0.44 MPa (45 kgf / cm²). 2 The test specimens obtained in this way were cut to a width of 10 mm, peeled off using an autograph, and the peel strength was measured. The average value for each N=5 measurement was calculated. A bonding peel strength (copper foil) of 4 or higher is preferable.

[0091] [Adhesive Peel Strength (LCP)] Copper foil was attached to one side of the adhesive film with the roughened side facing inward, and LCP was bonded to the other side. The films were then heat-pressed together using a press machine. The heat-pressing conditions were 200°C, 75 minutes, and 0.44 MPa (45 kgf / cm²). 2 The test specimens obtained in this manner were cut to a width of 10 mm, peeled off using an autograph, and the peel strength was measured. The average value for each N=5 measurement was calculated. A bonding peel strength (LCP) of 3 or higher is preferable.

[0092] [Flow rate] The measurement of the flow rate was performed by the method as shown in FIGS. 1 to 3. FIGS. 1 to 3 are schematic diagrams for explaining the method of measuring the flow rate. In FIGS. 1 to 3, (a) is a plan view of a test piece used for measuring the flow rate, and (b) shows the cross section A-A' of FIG. 1, the cross section B-B' of FIG. 2, and the cross section C-C' of FIG. 3, respectively. For the measurement of the flow rate, first, as shown in FIG. 1, a copper foil 12 with a thickness of 18 μm was bonded to one side of an adhesive film 11 cut out to 100 mm × 100 mm with the glossy surface facing inward. The size of the copper foil 12 was also 100 mm × 100 mm, the same as that of the adhesive film 11. Next, as shown in FIG. 2, at each intermediate part of each side of the square periphery of the adhesive film 11 bonded to the copper foil 12, a hole 20 with a diameter of 6 mm penetrating the adhesive film 11 and the copper foil 12 was punched with a punch to produce a test piece 10 for measuring the flow rate. Next, as shown in FIG. 3, an LCP 13 was attached to one side of the obtained test piece 10 and thermocompression bonded with a press machine. The conditions for thermocompression bonding were 200 °C, 75 minutes, and 0.44 MPa (45 kgf / cm 2 ). After press curing, the part where the hole 20 was made in the test piece 10 was observed with an electron microscope, and the length (μm) of the resin flow at each part (4 points) where the hole 20 was made was measured. The length (μm) of the resin flow was measured as the length of the largest part of the resin flow for each part where the hole 20 was made. Then, the average value of the resin flow lengths at the 4 points was used as the measured value in the evaluation of the flow rate. In the evaluation of the flow rate, the above-mentioned measured value (average value) needs to be 150 μm or less, and it is more preferable that it is 80 μm or less.

[0093] 〔Reliability (Moisture Absorption Reflow)〕 An LCP cut out to 100 mm × 100 mm was bonded to both sides of an adhesive film cut out to 100 mm × 100 mm and thermocompression bonded with a press machine. The conditions for thermocompression bonding were 200 °C, 75 minutes, and 0.44 MPa (45 kgf / cm 2) was performed. Five strips measuring 10 mm x 100 mm were cut from the test specimens obtained in this manner and placed in a constant temperature bath at 85°C and 85% humidity for 12 hours. After 12 hours, the test specimens were removed from the constant temperature bath and passed through a 260°C reflow oven five times. If there was no swelling or peeling after the moisture absorption reflow, the specimen was considered a pass and was marked "Pass" in Tables 1 to 4. On the other hand, if there was swelling or peeling after the moisture absorption reflow, the specimen was considered a failure and was marked "NG" in Tables 1 to 4.

[0094] [Solder heat resistance test] The procedure was carried out in accordance with JIS C5012 (1993). Specifically, copper foil was bonded to both sides of the adhesive film with the roughened side facing inward, and then heat-pressed using a press machine. The heat-pressure conditions were 200°C, 75 minutes, and 0.44 MPa (45 kgf / cm²). 2 The obtained test specimens were cut to 25mm x 25mm and floated in a solder bath heated to 288°C for 3 minutes to check for blistering. If no blistering occurred after 3 minutes, it was considered a pass and was marked "Pass" in Tables 1 to 4. On the other hand, if blistering occurred within 3 minutes, it was considered a failure and was marked "NG" in Tables 1 to 4.

[0095] [Table 1]

[0096] [Table 2]

[0097] [Table 3]

[0098] [Table 4]

[0099] 〔result〕 As shown in Tables 1 to 3, the resin compositions of Examples 1 to 14, in which the average styrene ratio of component (A) was set to a predetermined value, showed good results in all evaluations of dielectric constant (ε), dielectric loss tangent (tanδ), adhesive peel strength (copper foil), adhesive peel strength (LCP), flow rate, reliability (moisture-absorbing reflow), and solder heat resistance test. In particular, the resin compositions of Examples 1 to 14 were able to produce adhesive films in which the resin flow could be suppressed to 150 μm or less in flow rate measurements, and were able to suppress resin flow in the perforated areas when multilayering high-frequency substrates.

[0100] The resin composition of Comparative Example 1 had too high a styrene ratio in component (A), making it impossible to form a film. The resin composition of Comparative Example 2 had too low a styrene ratio in component (A), resulting in a resin flow of 200 μm during flow rate measurement. The resin composition of Comparative Example 3 did not contain epoxy resin as component (B), and therefore failed the evaluation of adhesive peel strength (LCP), reliability (moisture-absorbing reflow), and solder heat resistance tests. The resin composition of Comparative Example 4 did not contain styrene / butadiene / butylene / styrene block copolymer (SBBS) as component (A), but instead contained styrene / butadiene / styrene block copolymer (SBS(1)), and therefore failed the evaluation of dielectric loss tangent (tanδ), adhesive peel strength (LCP), and flow rate. The resin composition of Comparative Example 5 also did not contain styrene / butadiene / butylene / styrene block copolymer (SBBS) as component (A), but instead contained styrene / butadiene / styrene block copolymer (SEBS(1)), and failed the reliability (moisture absorption reflow) and solder heat resistance tests. [Industrial applicability]

[0101] The resin composition of the present invention can be used as a resin composition for adhesive films. Furthermore, the adhesive film and interlayer bonding sheet of the present invention can be used in interlayer fume-reducing films for printed circuit boards, in the manufacture of electronic components, and the like. [Explanation of symbols]

[0102] 10 test specimens 11 Adhesive film 12 Copper foil 13 LCP 20 holes

Claims

1. (A) Styrene / butadiene / butylene / styrene block copolymer, (B) Epoxy resin and (C) Thermosetting resins other than epoxy resins, (E) Organic peroxides and Includes, The styrene ratio of component (A) is 31-60%, The weight-average molecular weight of component (A) is 30,000 to 300,000. The (C) component is a thermosetting resin with a dielectric constant of 3.0 or less in the 10 GHz frequency region. The aforementioned component (A) is a hydrogenated styrene-based thermoplastic elastomer in which a portion of the double bonds are selectively hydrogenated. A resin composition wherein component (C) has a carbon-carbon double bond at its terminal end.

2. The above-mentioned component (A) is, (A1) A first styrene / butadiene / butylene / styrene block copolymer with a styrene ratio of 40% or more, (A2) A second styrene / butadiene / butylene / styrene block copolymer with a styrene ratio of less than 40%, The resin composition according to claim 1, comprising:

3. The resin composition according to claim 1 or 2, wherein the (C) component is a thermosetting resin having a dielectric loss tangent of 0.004 or less in the 10 GHz frequency region.

4. The resin composition according to claim 1 or 2, wherein the styrene ratio of component (A) is 33 to 46%.

5. The resin composition according to claim 1 or 2, wherein the (C) component is a terminally modified polyphenylene ether resin.

6. The resin composition according to claim 1 or 2, wherein the (C) component is a modified polyphenylene ether resin having carbon-carbon double bonds at its termini.

7. The resin composition according to claim 1 or 2, wherein the content ratio of component (C) to component (A) is, by mass ratio, component (C) : component (A) = 10:90 to 40:

60.

8. The resin composition according to claim 1 or 2, wherein the component (B) is contained in an amount of 0.1 to 3% by mass relative to 100% by mass of the resin component in the resin composition.

9. (D) The resin composition according to claim 1 or 2, further comprising a curing catalyst.

10. An adhesive film using the resin composition according to claim 1 or 2.

11. A layer-indirect bonding sheet using the resin composition according to claim 1 or 2.

12. A cured product comprising the resin composition according to claim 1 or 2.

13. A cured product comprising the adhesive film described in claim 10.

14. A laminate comprising members containing a liquid crystal polymer using the interlayer bonding sheet described in claim 11.

15. A cured product comprising the laminate described in claim 14.

16. A laminate using the resin composition according to claim 1 or 2.

17. A semiconductor device using the resin composition described in claim 1 or 2.

18. The process comprises a step of mixing (A) styrene / butadiene / butylene / styrene block copolymer, (B) epoxy resin, and (C) thermosetting resin other than epoxy resin. As component (A), at least (A1) a first styrene / butadiene / butylene / styrene block copolymer having a styrene ratio of 40% or more, and (A2) a second styrene / butadiene / butylene / styrene block copolymer having a styrene ratio of less than 40%, The mixing ratio of component (A1) and component (A2) is adjusted so that the styrene ratio of component (A) is 31-60%. As component (C), a thermosetting resin with a dielectric constant of 3.0 or less in the 10 GHz frequency region and having carbon-carbon double bonds at its ends is used. A method for producing a resin composition, wherein the component (A) is a hydrogenated styrene-based thermoplastic elastomer in which a portion of the double bonds are selectively hydrogenated.

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