JP5265449B2 - Resin composition, method for producing resin composition, prepreg, metal-clad laminate, and printed wiring board - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a resin composition which has a low viscosity while maintaining excellent dielectric properties possessed by PPE and excels in the heat resistance of a cured product and the adhesion to a copper foil and the like. <P>SOLUTION: The resin composition includes a reaction product between a low-molecular weight polyphenylene ether having a number average molecular weight of 800-2,000 and averaging 1.5-2 hydroxyl groups per molecule and a low epoxy group number epoxy resin having averaging 2.3 or less epoxy groups per molecule, and a thermosetting resin. <P>COPYRIGHT: (C)2011,JPO&amp;INPIT

Description

  The present invention provides a resin composition suitably used for an insulating material of a printed wiring board, a method for producing the resin composition, a prepreg using the resin composition, a metal-clad laminate using the prepreg, and the metal The present invention relates to a printed wiring board using a tension laminate.

  2. Description of the Related Art In recent years, with various types of electronic equipment, mounting techniques such as higher integration of semiconductor devices to be mounted, higher density of wiring, and multilayering have rapidly progressed as the amount of information processing has increased. Insulating materials such as printed wiring boards used in various electronic devices are required to have a low dielectric constant and dielectric loss tangent in order to increase signal transmission speed and reduce loss during signal transmission.

  Polyphenylene ether (PPE) has excellent dielectric properties such as dielectric constant and dielectric loss tangent even in the high frequency band (high frequency region) from the MHz band to the GHz band, so printed wiring boards for electronic devices that use the high frequency band, etc. The insulating material is preferably used. However, since high molecular weight PPE generally has a high melting point, it tends to have high viscosity and low fluidity. Then, using such PPE, a prepreg used for manufacturing a multilayer printed wiring board or the like is formed, and when a printed wiring board is manufactured using the formed prepreg, at the time of manufacturing, for example, at the time of multilayer molding Forming defects such as generation of voids occurred, and there was a problem of formability that it was difficult to obtain a highly reliable printed wiring board. In order to solve such problems, for example, a technique for causing molecular cleavage by causing a redistribution reaction of high molecular weight PPE in a solvent in the presence of a phenol species and a radical initiator to lower the molecular weight of PPE. It has been known. However, when the molecular weight of PPE is lowered, there is a problem that the curing becomes insufficient and the heat resistance of the cured product is lowered.

  Then, in order to improve the heat resistance etc. of hardened | cured material, as described in the following patent document 1 and the following patent document 2, it is possible to use PPE combining thermosetting resins, such as an epoxy resin. Specifically, Patent Document 1 describes a curable resin composition containing at least one PPE having a number average molecular weight of less than about 3000 and at least one thermosetting resin. Patent Document 2 discloses, in advance, an epoxy compound having at least two epoxy groups in one molecule and a phenol-modified PPE obtained by redistributing PPE in the presence of phenols and a radical initiator. An epoxy resin composition containing a reacted prereacted material and a cyanate compound as an essential component is described.

JP-A-11-302529 JP-A-10-279781

  However, even when a curable resin composition containing a polyphenylene ether resin and a thermosetting resin as in Patent Document 1 is used, the reactivity between the polyphenylene ether resin and the thermosetting resin is insufficient during curing. The heat resistance of the cured product could not be sufficiently improved.

  Patent Document 2 discloses that heat resistance and electrical characteristics can be improved, but phenol-modified PPE obtained by redistributing PPE in the presence of phenols and a radical initiator. Has a broad molecular weight distribution and a low hydroxyl group concentration at the terminal, so that the reactivity is low, and there is a tendency that it cannot sufficiently react with the thermosetting resin at the time of curing. And even if it is a case where the preliminary reaction thing made to react with an epoxy compound previously like patent document 2 is used, since the reactivity of PPE is low, it cannot be said that heat resistance, adhesiveness, etc. are high enough. It was. Moreover, when a highly reactive polyfunctional epoxy compound is used as an epoxy compound to be reacted in advance in order to increase the reactivity, the viscosity is excessively increased, and in some cases, the gel is formed to produce a printed wiring board. There was a problem that it could not be used for prepreg.

  The present invention has been made in view of such circumstances, and maintains a superior dielectric property possessed by PPE, has a low viscosity, and is excellent in heat resistance of a cured product and adhesiveness with a copper foil and the like. The purpose is to provide goods. Another object of the present invention is to provide a method for producing the resin composition, a prepreg using the resin composition, a metal-clad laminate using the prepreg, and a printed wiring board using the metal-clad laminate.

  The resin composition of the present invention comprises a low molecular weight polyphenylene ether having a number average molecular weight of 800 to 2000 and having an average of 1.5 to 2 hydroxyl groups in one molecule and an epoxy having an average of 2.3 or less in one molecule. It contains a reaction product with a low epoxy group epoxy resin having a group and a thermosetting resin.

  According to the said structure, the resin composition excellent in the heat resistance of cured | curing material and adhesiveness with copper foil etc. can be obtained, maintaining the outstanding dielectric characteristic which PPE has.

  This is considered to be due to the following.

  First, the heat resistance of the cured product can be improved by using a reaction product obtained by reacting a hydroxyl group of PPE, which tends to have low heat resistance, with an epoxy group of an epoxy resin having high heat resistance in advance. it is conceivable that. At that time, PPE having a relatively high reactivity having an average of 1.5 to 2 hydroxyl groups in one molecule and an average of 2.3 or less epoxy groups in one molecule as an epoxy resin are used. It is considered that not only can the heat resistance of the cured product be improved but also an increase in viscosity can be suppressed by using the low epoxy group number epoxy resin. And by containing the reaction product and the thermosetting resin, even when the reactivity between the reaction product and the thermosetting resin is somewhat low at the time of curing, the heat resistance of the cured product and the copper foil, etc. It is thought that this is because the adhesion can be sufficiently increased. Therefore, it is considered that it is possible to obtain a resin composition having a low viscosity and excellent in heat resistance of the cured product and adhesiveness with a copper foil while maintaining the excellent dielectric properties of PPE.

  Moreover, it is preferable that the said thermosetting resin contains at least 1 sort (s) of an epoxy resin and cyanate resin. According to this structure, what was excellent by the heat resistance of hardened | cured material and adhesiveness with copper foil etc. can be obtained. This is considered to be because the thermosetting resin easily reacts with a hydroxyl group or an epoxy group of the reaction product at the time of curing.

  The number of epoxy groups in one molecule of the low epoxy group epoxy resin is preferably 2 to 2.3 on average. According to this structure, the thing excellent in the heat resistance of hardened | cured material and adhesiveness with copper foil etc. can be obtained, suppressing a raise of a viscosity.

  Moreover, it is preferable that the said reaction product is a thing obtained by making 2 mol or more of said low epoxy group number epoxy resins react with 1 mol of said low molecular weight polyphenylene ether. According to this configuration, it is possible to obtain a product having a low viscosity and excellent in heat resistance of the cured product and adhesiveness with a copper foil or the like.

  Moreover, it is preferable to contain 5-30 mass parts of at least 1 sort (s) of a phosphinate flame retardant and a melamine flame retardant with respect to a total of 100 mass parts of the said reaction product and the said thermosetting resin. According to this configuration, not only the viscosity is low and the cured product has excellent heat resistance and adhesion to copper foil, but also the cured product has sufficiently high flame retardancy.

  The melamine compound is preferably melamine polyphosphate. According to this configuration, a cured product having higher flame retardancy can be obtained.

  Moreover, the method for producing the resin composition of the present invention comprises a low molecular weight polyphenylene ether having a number average molecular weight of 800 to 2000 and an average of 1.5 to 2 hydroxyl groups in one molecule, and an average of 2. A step of reacting a hydroxyl group of the low molecular weight polyphenylene ether with an epoxy group of the low epoxy group epoxy resin by heating a mixture of the low epoxy group epoxy resin having 3 or less epoxy groups, and a hydroxyl group of the low molecular weight polyphenylene ether And a step of blending a thermosetting resin with a reaction product obtained by reacting an epoxy group of a low epoxy group number epoxy resin.

  According to the said structure, the resin composition excellent in the heat resistance of cured | curing material and adhesiveness with copper foil etc. can be obtained, maintaining the outstanding dielectric characteristic which PPE has.

  The prepreg of the present invention is obtained by impregnating a fibrous base material with the resin composition. According to this configuration, it is suitable for producing a metal-clad laminate having excellent dielectric properties and heat resistance, and excellent adhesion to a metal foil such as a copper foil. Since the viscosity is low and the fluidity is high, it is possible to obtain a highly reliable material that can suppress the occurrence of molding defects when manufacturing a metal-clad laminate or a printed wiring board using a metal-clad laminate.

  In addition, the metal-clad laminate of the present invention is obtained by laminating a metal foil on the prepreg and molding by heating and pressing. According to this configuration, a printed wiring board having excellent dielectric properties and heat resistance, and excellent adhesion between a metal foil such as a copper foil and a prepreg can be produced while suppressing the occurrence of molding defects, and has excellent reliability. A metal-clad laminate is obtained.

  The printed wiring board of the present invention is obtained by forming a circuit by partially removing the metal foil on the surface of the metal-clad laminate. According to this structure, the thing which was excellent in dielectric characteristics and heat resistance, excellent in the adhesiveness between metal foil and a prepreg, and also the generation | occurrence | production of the molding defect was suppressed is obtained.

  According to the present invention, it is possible to provide a resin composition having a low viscosity, excellent heat resistance of a cured product, and excellent adhesion to a copper foil or the like while maintaining excellent dielectric properties of PPE. Moreover, the manufacturing method of the said resin composition, the prepreg using the said resin composition, the metal-clad laminated board using the said prepreg, and the printed wiring board using the said metal-clad laminated board are provided.

  The resin composition of the present invention comprises a low molecular weight polyphenylene ether having a number average molecular weight of 800 to 2000 and having an average of 1.5 to 2 hydroxyl groups in one molecule and an epoxy having an average of 2.3 or less in one molecule. It contains a reaction product with a low epoxy group epoxy resin having a group and a thermosetting resin. That is, the resin composition is obtained by blending the thermosetting resin after prereacting the low molecular weight polyphenylene ether and the low epoxy group number epoxy resin in advance.

  As described above, the resin composition contains a reaction product of the low molecular weight polyphenylene ether and the low epoxy group number epoxy resin. The reaction product is not particularly limited as long as it is a product obtained by reacting (prereacting) a hydroxyl group (OH group) of the low molecular weight polyphenylene ether with an epoxy group of the low epoxy group number epoxy resin. Specifically, for example, one obtained by reacting 2 mol or more of the low epoxy group number epoxy resin to 1 mol of the low molecular weight polyphenylene ether can be used. More specifically, for example, it can be obtained by reacting as follows. First, the low molecular weight polyphenylene ether and the low epoxy group number epoxy resin are stirred in an organic solvent for 10 to 60 minutes so that the low molecular weight polyphenylene ether and the low epoxy group number epoxy resin have a predetermined ratio. Mix. In that case, as a ratio of the low molecular weight polyphenylene ether and the low epoxy group number epoxy resin, for example, a molar ratio of 1: 2 to 1: 4 is preferable. And after mixing the said low molecular weight polyphenylene ether and the said low epoxy group number epoxy resin, the said low molecular weight polyphenylene ether and the said low epoxy group number epoxy resin are made to react by heating at 80-110 degreeC for 2 to 12 hours. . By doing so, the reaction product is obtained. The organic solvent is not particularly limited as long as it dissolves the low molecular weight polyphenylene ether, the low epoxy group number epoxy resin, and the like and does not inhibit these reactions. Specifically, toluene etc. are mentioned, for example.

  When the low molecular weight polyphenylene ether and the low epoxy group number epoxy resin are reacted, a catalyst may be mixed with the mixture of the low molecular weight polyphenylene ether and the low epoxy group number epoxy resin. The catalyst can be used without particular limitation as long as it can promote the reaction between the hydroxyl group of the low molecular weight polyphenylene ether and the epoxy group of the low epoxy group number epoxy resin. Specifically, organic metal salts such as Zn, Cu and Fe of organic acids such as octanoic acid, stearic acid, acetylacetonate, naphthenic acid and salicylic acid; tertiary amines such as triethylamine and triethanolamine; 2 -Imidazoles such as ethyl-4-imidazole (2E4MZ) and 4-methylimidazole; and organic phosphines such as triphenylphosphine, tributylphosphine, tetraphenylphosphonium / tetraphenylborate and the like. These may be used alone or in combination of two or more. Among these, imidazoles, particularly 2-ethyl-4-imidazole, can shorten the reaction time, and further can suppress polymerization of the low epoxy group number epoxy resins (self-polymerization of epoxy resins). Are particularly preferably used. Moreover, it is preferable that content of the said catalyst is 0.05-1 mass part with respect to a total of 100 mass parts of the said low molecular weight polyphenylene ether and the said low epoxy group number epoxy resin. If the content of the catalyst is too small, the reaction between the hydroxyl group of the low molecular weight polyphenylene ether and the epoxy group of the low epoxy group epoxy resin tends to take a long time. It becomes difficult and tends to gel.

  The low molecular weight polyphenylene ether is not particularly limited as long as it is a polyphenylene ether having a number average molecular weight (Mn) of 800 to 2000 and an average of 1.5 to 2 hydroxyl groups in one molecule. Specific examples include those having a number average molecular weight of 800 to 2000 directly obtained by a polymerization reaction. In addition, when the number average molecular weight is less than 800, even if it is reacted with the low epoxy group number epoxy resin, sufficient heat resistance of the cured product cannot be obtained, and when the number average molecular weight exceeds 2000, the low When a reaction product obtained by reacting with an epoxy resin having an epoxy group number is contained, the viscosity of the resin composition becomes high, sufficient fluidity cannot be obtained, and molding defects cannot be suppressed. Therefore, by using the low molecular weight polyphenylene ether, the dielectric properties are not only good in a wide frequency range, but also have sufficient fluidity to suppress molding defects. When the number of hydroxyl groups is less than 1.5, the reactivity of the reaction product obtained by reacting with the low epoxy group epoxy resin is lowered, and the heat resistance of the cured product of the obtained epoxy resin composition is lowered. In addition, when the number of hydroxyl groups exceeds two, the reactivity with the epoxy group of the low epoxy group number epoxy resin becomes too high, which may cause gelation.

  Specific examples of the low molecular weight polyphenylene ether include poly (2,6-dimethyl-1,4-phenylene oxide).

  The low epoxy group number epoxy resin is not particularly limited as long as the epoxy group has an epoxy group having an average of 2.3 or less per molecule. Specifically, for example, dicyclopentadiene type epoxy resin, bisphenol A type epoxy resin, bisphenol F type epoxy resin, phenol novolac type epoxy resin, naphthalene type epoxy resin, biphenyl type epoxy resin and the like can be mentioned. These may be used alone or in combination of two or more. Among these, bisphenol A type epoxy resin, bisphenol F type epoxy resin, and biphenyl type epoxy resin are preferably used from the viewpoint of good compatibility with the low molecular weight polyphenylene ether. In addition, although it is preferable that the said resin composition does not contain a halogenated epoxy resin, as long as the effect of this invention is not impaired, you may mix | blend as needed.

  Further, the low epoxy group number epoxy resin may have an average of 2.3 or less epoxy groups in one molecule, but is preferably an average of 2 or more. When there are too few epoxy groups, the reactivity of the reaction product obtained by reacting with the low molecular weight polyphenylene ether tends to decrease, and the heat resistance of the cured product of the resulting epoxy resin composition tends to decrease, When there are too many epoxy groups, the reactivity with the hydroxyl group of the low molecular weight polyphenylene ether becomes too high, which may cause gelation.

  Here, the number of hydroxyl groups of the low molecular weight polyphenylene ether and the number of epoxy groups of the low epoxy group epoxy resin can be understood from the standard values of the products of the low molecular weight polyphenylene ether and the low epoxy group epoxy resin used. Specific examples of the number of hydroxyl groups in the low molecular weight polyphenylene ether include a numerical value representing an average value of hydroxyl groups per molecule of all the low molecular weight polyphenylene ethers present in 1 mol of the low molecular weight polyphenylene ether. Can be mentioned. Further, the number of epoxy groups of the low epoxy group epoxy resin specifically includes, for example, an average of epoxy groups per molecule of all the low epoxy group epoxy resins present in 1 mol of the low epoxy group epoxy resin. A numerical value representing the value can be used. The low epoxy group epoxy resin has an epoxy group number of 2.3 or less.

  The thermosetting resin can be used without any particular limitation, and specific examples include an epoxy resin and a cyanate resin.

  The epoxy resin can be used without any particular limitation. Moreover, what has two or more epoxy groups in 1 molecule is preferable. Specifically, the same epoxy resin as the low epoxy group epoxy resin can be used, and more specifically, for example, dicyclopentadiene type epoxy resin, bisphenol A type epoxy resin, bisphenol F type epoxy resin, phenol novolac. Type epoxy resin, naphthalene type epoxy resin, biphenyl type epoxy resin and the like. These may be used alone or in combination of two or more. Among these, biphenyl type epoxy resins are preferably used from the viewpoint of good compatibility with the reaction product. In addition, although it is preferable that the said resin composition does not contain a halogenated epoxy resin, as long as the effect of this invention is not impaired, you may mix | blend as needed.

  The cyanate resin can be used without any particular limitation. Moreover, what has two or more cyanate groups in 1 molecule is preferable. Specifically, for example, 2,2-bis (4-cyanatophenyl) propane (bisphenol A type cyanate resin), bis (3,5-dimethyl-4-cyanatophenyl) methane, 2,2-bis ( And aromatic cyanate ester compounds such as 4-cyanatophenyl) ethane and derivatives thereof. These may be used alone or in combination of two or more.

  As the thermosetting resin, the epoxy resin and the cyanate resin may be used alone or in combination. Moreover, as content of the said thermosetting resin, it is 20-80 mass parts with respect to a total of 100 mass parts of the said reaction product and the said thermosetting resin, sufficient heat resistance and the outstanding dielectric material. This is preferable because the characteristics can be maintained.

  Moreover, it is preferable to mix | blend the curing catalyst for accelerating | stimulating the crosslinking reaction (curing reaction) with the said reaction product and the said thermosetting resin in the said resin composition. Even if not blended, the reaction can proceed if the temperature is raised, but depending on the process conditions, it may not be possible to raise the temperature. Therefore, it is preferable to blend the curing catalyst. Specific examples of such curing catalysts include, for example, organic metal salts such as Zn, Cu, and Fe of organic acids such as octanoic acid, stearic acid, acetylacetonate, naphthenic acid, and salicylic acid, triethylamine, and triethanol. Examples include tertiary amines such as amines, imidazoles such as 2-ethyl-4-imidazole, and 4-methylimidazole. These may be used alone or in combination of two or more. Among these, an organic metal salt, particularly zinc octoate, is particularly preferably used because high heat resistance can be obtained.

  The blending ratio of the curing catalyst is not particularly limited. For example, when an organometallic salt is used, 0.005 to 5 parts by mass with respect to 100 parts by mass in total of the reaction product and the thermosetting resin. In the case of using imidazoles, it is preferably 0.01 to 5 parts by mass with respect to 100 parts by mass in total of the reaction product and the thermosetting resin.

  It is preferable that a flame retardant is further blended in the resin composition. The flame retardant can be used without any particular limitation. Specific examples include phosphinate flame retardants and melamine flame retardants. Specific examples of the phosphinate flame retardant include phosphinic acid metal salts such as dialkylphosphinic acid aluminum salts. Examples of the melamine flame retardant include melamine phosphate and melamine polyphosphate, and melamine polyphosphate is preferably used as the melamine flame retardant. As said flame retardant, the said flame retardant may be used independently and may be used in combination of 2 or more type. In addition, the resin composition may include 5 to 30 parts by mass of at least one of the phosphinate flame retardant and the melamine flame retardant with respect to 100 parts by mass of the reaction product and the thermosetting resin. It is preferable to make it contain from the point which is excellent in a flame retardance and heat resistance. When the amount of the phosphinate flame retardant and the melamine flame retardant is too small, the flame retardancy tends to be insufficient, and when too large, the heat resistance and Tg tend to decrease.

  Moreover, you may mix | blend an inorganic filler with the said resin composition further as needed for the purpose of improving the dimensional stability at the time of a heating, or improving a flame retardance.

  Specific examples of the inorganic filler include silica, alumina, talc, aluminum hydroxide, magnesium hydroxide, titanium oxide, mica, aluminum borate, barium sulfate, and calcium carbonate. In addition, the inorganic filler may be used as it is, but it is particularly preferable that the surface is treated with an epoxy silane type or amino silane type silane coupling agent. A metal-clad laminate obtained by using a resin composition containing an inorganic filler surface-treated with a silane coupling agent as described above has high heat resistance during moisture absorption and also has high interlayer peel strength. Tend.

  The resin composition is blended with additives such as heat stabilizers, antistatic agents, ultraviolet absorbers, flame retardants, dyes, pigments, lubricants, etc., as necessary, as long as the effects of the present invention are not impaired. May be.

  In the present invention, the number average molecular weight of the low molecular weight polyphenylene ether, the low epoxy group number epoxy resin, the reaction product, and the thermosetting resin is specifically, for example, gel permeation chromatography. Can be measured.

  When the prepreg is produced, the resin composition is often prepared and used in the form of a varnish for the purpose of impregnating a base material (fibrous base material) for forming the prepreg. That is, the resin composition is usually often prepared in a varnish form. Such a varnish is prepared as follows, for example.

  First, the reaction product, the thermosetting resin, and the like are charged into an organic solvent and dissolved. At this time, heating may be performed as necessary. Furthermore, a varnish can be obtained by adding a curing catalyst, a flame retardant and an inorganic filler, which are used as necessary, and dispersing them to a predetermined dispersion state using a ball mill, a bead mill, a planetary mixer, a roll mill or the like. A resin composition is prepared. The organic solvent is not particularly limited as long as it dissolves the reaction product and the thermosetting resin and does not inhibit the curing reaction. Specifically, toluene etc. are mentioned, for example.

  Examples of a method for producing a prepreg using the obtained varnish-like resin composition include a method in which a fibrous base material is impregnated with the resin composition and then dried.

  Specific examples of the fibrous base material include glass cloth, aramid cloth, polyester cloth, glass nonwoven fabric, aramid nonwoven fabric, polyester nonwoven fabric, pulp paper, and linter paper. When a glass cloth is used, a laminate having excellent mechanical strength can be obtained, and a flat glass processed glass cloth is particularly preferable. Specifically, the flattening processing can be performed, for example, by continuously pressing a glass cloth with a press roll at an appropriate pressure and compressing the yarn flatly. In addition, as a thickness of the said fibrous base material, the thing of 0.04-0.3 mm can generally be used, for example.

  The impregnation is performed by dipping or coating. The impregnation can be repeated a plurality of times as necessary. At this time, it is also possible to repeat the impregnation using a plurality of solutions having different compositions and concentrations, and finally adjust to a desired composition and resin amount.

  The fibrous base material impregnated with the resin composition is heated at a desired heating condition, for example, 80 to 170 ° C. for 1 to 10 minutes to obtain a semi-cured (B stage) prepreg.

  As a method for producing a metal-clad laminate using the prepreg thus obtained, one or a plurality of the prepregs are stacked, and a metal foil such as a copper foil is stacked on both upper and lower surfaces or one surface thereof. By heating and pressing to laminate and integrate, a double-sided metal foil-clad laminate or a single-sided metal foil-clad laminate can be produced. The heating and pressing conditions can be appropriately set depending on the thickness of the laminate to be manufactured, the type of the resin composition of the prepreg, etc. For example, the temperature is 170 to 210 ° C., the pressure is 3.5 to 4.0 Pa, and the time For 60 to 150 minutes.

  Since the resin composition contains a reaction product obtained by previously reacting the low molecular weight polyphenylene ether and the low epoxy group number epoxy resin, the resin composition has a low viscosity and is cured while maintaining the excellent dielectric properties of the polyphenylene ether. It has excellent heat resistance and adhesion to copper foil. Therefore, the metal-clad laminate using the obtained prepreg can be produced while suppressing the occurrence of molding defects in the printed wiring board.

  And the printed wiring board which provided the conductor pattern as a circuit on the surface of a laminated body can be obtained by carrying out the etching process etc. of the metal foil on the surface of the produced laminated body. The printed wiring board thus obtained is excellent in dielectric characteristics and has high heat resistance.

  The present invention will be described more specifically with reference to the following examples. However, the scope of the present invention is not limited to these examples.

[Preparation of reaction product]
In this example, each component used in preparing the reaction product will be described.

(Polyphenylene ether)
PPE1: polyphenylene ether (MX90 manufactured by SABIC, number average molecular weight Mn1000, average number of hydroxyl groups in one molecule 1.7)
PPE2: polyphenylene ether obtained by reducing the molecular weight of a high molecular weight polyphenylene ether by a known molecular weight reduction method (molecular cutting method) (number average molecular weight Mn1500, average number of hydroxyl groups in one molecule 1.1)
(Epoxy resin)
Monofunctional epoxy resin: alkylphenol glycidyl ether (Epiclon 520 manufactured by DIC Corporation, number average molecular weight Mn210, average number of epoxy groups 1.0 in one molecule)
Bisphenol F type epoxy resin: Bisphenol F type epoxy resin (YDF8170 manufactured by Toto Kasei Co., Ltd., number average molecular weight Mn310, average number of epoxy groups 2.0 in one molecule)
Biphenyl type epoxy resin: Biphenyl type epoxy resin (NC3100 manufactured by Nippon Kayaku Co., Ltd., number average molecular weight Mn620, average number of epoxy groups 2.3 in one molecule)
Naphthalene novolac type epoxy resin: Naphthalene novolac type epoxy resin (Epiclon HP5000, number average molecular weight Mn780, manufactured by DIC Corporation, average number of epoxy groups 2.5 in one molecule)
Biphenyl type epoxy resin: Biphenyl type epoxy resin (Nippon Kayaku Co., Ltd. NC3000H, number average molecular weight Mn910, average number of epoxy groups in one molecule 3.4)
(Catalyst during pre-react)
Catalyst: 2-ethyl-4-imidazole (2E4MZ)
[Preparation method]
After adding each component to toluene so that it may become the mixture ratio of Table 1, it was made to stir at 100 degreeC for 6 hours. By doing so, the reaction product was prepared by pre-reacting with the low molecular weight polyphenylene ether and the low epoxy group number epoxy resin.

[Number average molecular weight Mn of reaction product]
The reaction product was measured for molecular weight distribution by gel permeation chromatography [HLC-8210 manufactured by Tosoh Corporation, column configuration: Super HM-M (1) + Super HM-H (1) manufactured by Tosoh Corporation]. The number average molecular weight was determined. In addition, when the reaction product is gelatinized, it cannot measure and shows in Table 1 "-".

[Prereact result]
When the obtained reaction product is visually evaluated to determine whether or not it is gelled, if it is not gelled and Mn of the reaction product is increased from Mn of PPE, in Table 1, “ “OK”. Further, in the case of gelation, “gelation” is shown in Table 1. Since the resin composition mentioned later cannot be prepared when it gelatinizes, the following compositions and evaluation are shown as "-" in Table 1. When no pre-react is performed, “None” is shown in Table 1.

[Preparation of resin composition]
In this example, each component used when preparing the resin composition will be described.

(Thermosetting resin)
Biphenyl type epoxy resin: Biphenyl type epoxy resin (Nippon Kayaku Co., Ltd. NC3000H, number average molecular weight Mn910, average number of epoxy groups in one molecule 3.4)
Bisphenol A type cyanate resin: 2,2-bis (4-cyanatophenyl) propane (BADCY made by Lonza Japan)
Phosphinate flame retardant: Aluminum dialkylphosphinate (OP935 manufactured by Clariant Japan)
Melamine flame retardant: Melamine polyphosphate (Melapur 200 manufactured by Ciba)
Curing catalyst: zinc octoate (manufactured by DIC Corporation)
[Preparation method]
The thermosetting resin was added to the obtained reaction product solution so as to have the blending ratio shown in Table 1, and then the mixture was stirred at room temperature for 30 minutes. By doing so, the thermosetting resin was completely dissolved and dispersed in the resulting reaction product solution. Then, a component other than the thermosetting resin was added and dispersed with a ball mill to obtain a varnish-like resin composition (resin varnish).

  Next, after impregnating the obtained resin varnish into a glass cloth (WEA116E manufactured by Nitto Boseki Co., Ltd.), prepreg was obtained by heating and drying at 150 ° C. for 3 to 5 minutes.

  And 6 sheets of each obtained prepreg are laminated | stacked and laminated | stacked, Furthermore, copper foil (Furukawa Circuit foil Co., Ltd. product GT-MP, thickness 18micrometer) is distribute | arranged to both the outer layers, respectively, the temperature of 220 degreeC and the pressure of 3 MPa By heating and pressing under conditions, a copper-clad laminate having a thickness of 0.75 mm was obtained.

  Each prepreg and copper clad laminate prepared as described above were evaluated by the method shown below.

[Melt viscosity of prepreg]
The melt viscosity at 130 ° C. of the prepreg was measured using a flow tester “CFT-500A” manufactured by Shimadzu Corporation.

[Glass transition temperature (Tg)]
The Tg of the prepreg was measured using a viscoelastic spectrometer “DMS100” manufactured by Seiko Instruments Inc. At this time, measurement was performed with a bending module at a frequency of 10 Hz, and Tg was a temperature at which tan α was maximized when the temperature was raised from room temperature to 280 ° C. under a temperature rising rate of 5 ° C./min.

[Copper foil adhesion strength]
The peel strength (copper foil adhesion strength) of the copper foil on the surface of the copper-clad laminate was measured according to JIS C 6481. At this time, a pattern having a width of 10 mm and a length of 100 mm was formed on a test piece having a width of 20 mm and a length of 100 mm. .

[Interlayer adhesion strength]
The peel strength (interlayer adhesion strength) between the prepregs of the copper clad laminate was measured according to JIS C 6481. At this time, a pattern having a width of 10 mm and a length of 100 mm is formed on a test piece having a width of 20 mm and a length of 100 mm, and the prepreg on the uppermost surface is peeled off at a speed of 50 mm / min by a tensile tester, and the peeling strength at that time Was measured.

[Heat resistance (T288)]
In accordance with IPC TM650, the heat resistance (T288) of the copper clad laminate was evaluated.

[Dielectric properties (dielectric constant and dielectric loss tangent)]
Using a cavity resonator “CP461” manufactured by Kanto Electronics Co., Ltd., the dielectric constant and dielectric loss tangent of the copper clad laminate at 2 GHz were measured.

[Flame retardance]
After removing the copper foil on the surface of the copper clad laminate, a test piece having a length of 125 mm and a width of 12.5 mm was cut out. Then, this test piece was evaluated according to "Test for Flammability of Plastic Materials-UL 94" of Underwriters Laboratories.

  These results are shown in Table 1.

  As can be seen from Table 1, low molecular weight polyphenylene ether (PPE1) having an average of 1.5 to 2 hydroxyl groups in one molecule and low epoxy group number epoxy having an average of 2.3 or less epoxy groups in one molecule. When a reaction product with a resin and at least one of a biphenyl type epoxy resin and a bisphenol A type cyanate resin are contained as a thermosetting resin (Examples 1 to 5), an average of 2.3 per molecule When pre-reacting using an epoxy resin having an epoxy group exceeding (Comparative Examples 1 to 3), pre-reacting using low molecular weight polyphenylene ether (PPE2) having an average of less than 1.5 hydroxyl groups in one molecule Compared to the cases (Comparative Examples 4 and 5) and the case of no pre-react (Comparative Example 6), the excellent dielectric properties of PPE are maintained. Low viscosity, a resin composition excellent in adhesion to the heat resistance and copper foil or the like of the cured product was obtained. In addition, when pre-reacting using an epoxy resin having an average of more than 2.3 epoxy groups in one molecule (Comparative Examples 1 to 3), gelation occurs during pre-react to prepare the reaction product, The resin composition could not be constructed.

  Furthermore, a reaction product obtained by reacting 2 moles or more of a low epoxy group number epoxy resin having an average of 2 to 2.3 epoxy groups in one molecule with respect to 1 mole of low molecular weight polyphenylene ether (PPE1). (Examples 2, 3, and 5) are used in the case of using a low epoxy group number epoxy resin having an average of less than 2 epoxy groups in one molecule (Example 1) or 1 mol of low molecular weight polyphenylene ether. On the other hand, it was found that the heat resistance was further improved as compared with the case where the reaction product obtained by reacting less than 2 mol of the low epoxy group number epoxy resin was used (Example 4).

Claims (11)

Low molecular weight polyphenylene ether having a number average molecular weight of 800 to 2000 and having an average of 1.5 to 2 hydroxyl groups in one molecule, and low epoxy group number epoxy resin having an average of 2.3 or less epoxy groups in one molecule The reaction product with
Containing thermosetting resin ,
The said thermosetting resin contains the cyanate resin which has a 2 or more cyanate group in 1 molecule, The resin composition characterized by the above-mentioned. The thermosetting resin may be 2,2-bis (4-cyanatophenyl) propane, bis (3,5-dimethyl-4-cyanatophenyl) methane, 2,2-bis (4- The resin composition of Claim 1 containing the 1 type, or 2 or more types of aromatic cyanate ester compound chosen from the group which consists of a cyanate phenyl) ethane and these derivatives. The thermosetting resin, the resin composition according to claim 1 or claim 2 further comprising an epoxy resin. The resin composition according to any one of claims 1 to 3 , wherein an average number of epoxy groups in one molecule of the low epoxy group number epoxy resin is 2 to 2.3. The resin composition according to any one of claims 1 to 4 , wherein the reaction product is obtained by reacting 2 mol or more of the low epoxy group number epoxy resin with respect to 1 mol of the low molecular weight polyphenylene ether. object. 6. The composition according to claim 1, comprising 5 to 30 parts by mass of at least one of a phosphinate flame retardant and a melamine flame retardant with respect to a total of 100 parts by mass of the reaction product and the thermosetting resin. 2. The resin composition according to item 1. The resin composition according to claim 6 , wherein the melamine flame retardant is melamine polyphosphate. Low molecular weight polyphenylene ether having a number average molecular weight of 800 to 2000 and having an average of 1.5 to 2 hydroxyl groups in one molecule, and low epoxy group number epoxy resin having an average of 2.3 or less epoxy groups in one molecule A step of reacting a hydroxyl group of a low molecular weight polyphenylene ether with an epoxy group of a low epoxy group number epoxy resin by heating the mixture with
Adding a thermosetting resin containing a cyanate resin having two or more cyanate groups in one molecule to a reaction product obtained by reacting a hydroxyl group of a low molecular weight polyphenylene ether and an epoxy group of a low epoxy group number epoxy resin; The manufacturing method of the resin composition characterized by the above-mentioned. A prepreg obtained by impregnating a fibrous base material with the resin composition according to any one of claims 1 to 7 . A metal-clad laminate obtained by laminating a metal foil on the prepreg according to claim 9 and heating and pressing. A printed wiring board obtained by forming a circuit by partially removing the metal foil on the surface of the metal-clad laminate according to claim 10 .