JP5186456B2 - Resin composition, prepreg, metal-clad laminate, and printed wiring board - Google Patents

Description

  The present invention relates to a resin composition suitably used as an insulating material for a printed wiring board, a prepreg using the resin composition, a metal-clad laminate using the prepreg, and a printed wiring manufactured using the prepreg. Regarding the board.

  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.

  In addition, since PPE is relatively poor in flame retardancy, resin compositions used as insulating materials such as printed wiring boards generally include halogen flame retardants such as brominated flame retardants and tetrabromobisphenol. In many cases, a halogen-containing compound such as a halogen-containing epoxy resin such as an A-type epoxy resin is blended. However, a cured product of such a halogen-containing resin composition may generate harmful substances such as hydrogen halide during combustion, and has a drawback of adversely affecting the human body and the natural environment. Against this background, non-halogenated materials are required as insulating materials for printed wiring boards and the like.

  Thus, specific examples of the non-halogenated resin composition include the composition described in Patent Document 1 below. Patent Document 1 includes a phosphorus flame retardant having a phosphorus content of 20 to 30% by mass, a polyphenylene ether resin having a number average molecular weight of 1000 to 4000, a non-halogen-containing thermosetting resin, and a curing agent for the thermosetting resin. The resin composition containing is described.

JP 2004-315725 A

  According to Patent Document 1, it is disclosed that excellent heat resistance, flame retardancy, and dielectric properties can be exhibited without containing a halogen compound. However, as in Patent Document 1, even when a phosphorus-based flame retardant is contained, it is difficult to sufficiently exhibit the flame retardancy of the cured product when low molecular weight PPE is used. Moreover, even if the flame retardancy can be increased to some extent by containing a relatively large amount of the phosphorus-based flame retardant, there is a problem that it is difficult to sufficiently increase the heat resistance.

  This is considered to be due to the following. As described above, low molecular weight PPE tended to have low heat resistance. Then, it is thought that the resin composition containing low molecular weight PPE and an epoxy compound can improve the heat resistance of hardened | cured material by advancing the hardening reaction of PPE and an epoxy compound. However, it is considered that the phosphorus-based flame retardant inhibits the curing reaction between PPE and the epoxy compound. That is, when a relatively large amount of a phosphorus-based flame retardant that can sufficiently increase the heat resistance of the cured product is contained, the curing reaction between PPE and the epoxy compound proceeds as the heat resistance of the cured product is sufficiently increased. It is thought that it becomes difficult.

  Therefore, it is considered that it is difficult to increase both the flame retardancy and the heat resistance by including a phosphorus flame retardant.

  The present invention has been made in view of such circumstances, and an object thereof is to provide a resin composition having excellent heat resistance and flame retardancy of a cured product while maintaining excellent dielectric properties of PPE. To do. Moreover, it aims at providing the prepreg using the said resin composition, the metal-clad laminated board using the said prepreg, and the printed wiring board manufactured using the said prepreg.

  The resin composition according to one embodiment of the present invention includes a low molecular weight polyphenylene ether having a number average molecular weight of 500 to 2000 and an average of 1.5 to 2 hydroxyl groups in one molecule, and an average of 2 or more in one molecule. An epoxy compound having an epoxy group, a cyanate compound having an average of two or more cyanate groups in one molecule, a phosphinate flame retardant, and a polyphosphate flame retardant having a triazine skeleton, The atomic content is 3.5% by mass or more.

  According to the above configuration, a resin composition excellent in heat resistance and flame retardancy of a cured product can be obtained while maintaining excellent dielectric properties of PPE. Furthermore, even if it does not contain what is generally used as a flame retardant aid, such as aluminum hydroxide or magnesium hydroxide, sufficiently high flame retardancy can be exhibited.

  This is considered to be due to the following.

  First, the polyphosphate flame retardant having a triazine skeleton is considered to be able to suppress the inhibition of the curing reaction between a low molecular weight polyphenylene ether, an epoxy compound and a cyanate compound among halogen-free phosphorus flame retardants. . In addition, if the polyphosphate flame retardant is contained in a large amount to increase the flame retardancy, the dielectric properties tend to be lowered.

  Such a polyphosphate flame retardant is used in combination with the phosphinate flame retardant, and the polyphosphate flame retardant and the phosphinate salt are used so that the phosphorus atom content falls within the above range. By containing a flame retardant, the inhibition of the curing reaction between the low molecular weight polyphenylene ether, the epoxy compound and the cyanate compound is suppressed while maintaining the excellent dielectric properties of the PPE, and moreover, when either one is contained. It is thought that high flame retardancy can be exhibited.

  Furthermore, it is considered that the curing reaction between the low molecular weight polyphenylene ether, the epoxy compound and the cyanate compound can be promoted by using the epoxy compound and the cyanate compound together.

  From the above, while exhibiting sufficiently high flame retardancy, the curing reaction of low molecular weight polyphenylene ether with epoxy compound and cyanate compound proceeds suitably, so that the excellent dielectric properties possessed by PPE are maintained and cured. It is thought that the heat resistance of an object can be improved. Therefore, it is thought that the resin composition excellent in the heat resistance and flame retardance of hardened | cured material can be obtained, maintaining the outstanding dielectric characteristic which PPE has.

  Moreover, each content of the said low molecular weight polyphenylene ether, the said epoxy compound, and the said cyanate compound is 15-75 mass respectively with respect to a total of 100 mass parts of the said low molecular weight polyphenylene ether, the said epoxy compound, and the said cyanate compound. Parts, 15 to 75 parts by mass, and 5 to 50 parts by mass. According to such a configuration, it is possible to obtain a resin composition that is more excellent in the heat resistance and flame retardancy of the cured product while maintaining the excellent dielectric properties of the PPE. This is considered to be because the curing reaction of the low molecular weight polyphenylene ether with the epoxy compound and the cyanate compound proceeds more suitably.

  Moreover, it is preferable that pH of the said polyphosphate flame retardant is 4-7. According to such a configuration, it is possible to obtain a resin composition that is more excellent in the heat resistance and flame retardancy of the cured product while maintaining the excellent dielectric properties of the PPE. This is considered to be due to the fact that when the pH is within the above range, the flame retardancy is further increased, and further, inhibition of the curing reaction between the low molecular weight polyphenylene ether, the epoxy compound and the cyanate compound is further suppressed. It is done.

  The polyphosphate flame retardant is preferably melamine polyphosphate. According to such a structure, the resin composition excellent in the heat resistance and flame retardance of hardened | cured material can be provided.

  The resin composition according to another embodiment of the present invention includes a low molecular weight polyphenylene ether having a number average molecular weight of 500 to 2000 and an average of 1.5 to 2 hydroxyl groups in one molecule, and one molecule. Polyphosphoric acid having an epoxy compound having an average of 2 to 2.3 epoxy groups and a reaction product of a cyanate compound having two or more cyanate groups in one molecule, a phosphinate flame retardant, and a triazine skeleton It contains a salt-based flame retardant.

  According to the above configuration, a resin composition excellent in heat resistance and flame retardancy of a cured product can be obtained while maintaining excellent dielectric properties of PPE.

  This is considered to be due to the following.

  First, the polyphosphate flame retardant having a triazine skeleton is considered to be able to suppress the inhibition of the curing reaction between a low molecular weight polyphenylene ether, an epoxy compound and a cyanate compound among halogen-free phosphorus flame retardants. . In addition, if the polyphosphate flame retardant is contained in a large amount to increase the flame retardancy, the dielectric properties tend to be lowered.

  Such a polyphosphate flame retardant is used in combination with the phosphinate flame retardant, and the polyphosphate flame retardant and the phosphinate salt are used so that the phosphorus atom content falls within the above range. By containing a flame retardant, the inhibition of the curing reaction between the low molecular weight polyphenylene ether, the epoxy compound and the cyanate compound is suppressed while maintaining the excellent dielectric properties of the PPE, and moreover, when either one is contained. It is thought that high flame retardancy can be exhibited.

  Furthermore, it is considered that the heat resistance of the cured product can be improved by using a reaction product obtained by previously reacting PPE, which tends to have low heat resistance, with an epoxy compound and cyanate compound having high heat resistance. . Moreover, it is thought that the curing reaction of low molecular weight polyphenylene ether, an epoxy compound, and a cyanate compound can be accelerated | stimulated by using an epoxy compound and a cyanate compound together in that case.

  From the above, while exhibiting sufficiently high flame retardancy, the curing reaction of low molecular weight polyphenylene ether with epoxy compound and cyanate compound proceeds suitably, so that the excellent dielectric properties possessed by PPE are maintained and cured. It is thought that the heat resistance of an object can be improved. Therefore, it is thought that the resin composition excellent in the heat resistance and flame retardance of hardened | cured material can be obtained, maintaining the outstanding dielectric characteristic which PPE has.

  The prepreg according to another aspect of the present invention is obtained by impregnating a fibrous base material with the resin composition. According to such a structure, what can manufacture the metal-clad laminated board excellent in a dielectric characteristic, heat resistance, and a flame retardance is obtained. Moreover, since the polyphenylene ether contained in the resin composition has a low molecular weight, the resin composition has a low viscosity and a high fluidity. Therefore, the obtained prepreg is excellent in reliability capable of suppressing the occurrence of molding defects when manufacturing a metal-clad laminate or a printed wiring board using the metal-clad laminate.

  In addition, the metal-clad laminate according to another aspect of the present invention is obtained by laminating a metal foil on the prepreg and heating and pressing. According to such a configuration, a highly reliable metal-clad laminate capable of producing a printed wiring board excellent in dielectric properties, heat resistance, and flame retardancy while suppressing the occurrence of molding defects can be obtained.

  A printed wiring board according to another aspect of the present invention is manufactured using the prepreg. According to such a configuration, it is possible to obtain one that is excellent in dielectric properties, heat resistance, and flame retardancy, and that further suppresses the occurrence of molding defects.

  ADVANTAGE OF THE INVENTION According to this invention, the resin composition excellent in the heat resistance and flame retardance of hardened | cured material can be provided, maintaining the outstanding dielectric characteristic which PPE has. Moreover, the prepreg using the said resin composition, the metal-clad laminated board using the said prepreg, and the printed wiring board manufactured using the said prepreg are provided.

  The resin composition according to the embodiment of the present invention includes a low molecular weight polyphenylene ether having a number average molecular weight of 500 to 2000 and an average of 1.5 to 2 hydroxyl groups in one molecule, and an average of 2 or more in one molecule. An epoxy compound having an epoxy group, a cyanate compound having an average of two or more cyanate groups in one molecule, a phosphinate flame retardant, and a polyphosphate flame retardant having a triazine skeleton, The atomic content is 3.5% by mass or more.

  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 500 to 2000 and an average of 1.5 to 2 hydroxyl groups in one molecule. Specifically, for example, those having a number average molecular weight of 500 to 2000 directly obtained by a polymerization reaction can be mentioned. On the other hand, if the molecular weight of the low molecular weight polyphenylene ether is too low, there is a tendency that sufficient heat resistance of the cured product cannot be obtained. On the other hand, if the molecular weight of the low molecular weight polyphenylene ether is too high, the melt viscosity becomes high, sufficient fluidity cannot be obtained, and molding defects tend not to 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. In addition, when the average number of hydroxyl groups per molecule (average number of hydroxyl groups) of the low molecular weight polyphenylene ether is too small, the reactivity with the epoxy group of the epoxy compound or the cyanate group of the cyanate compound is lowered, and a cured product is obtained. There is a tendency that sufficient heat resistance cannot be obtained. Moreover, when the average number of hydroxyl groups of the low molecular weight polyphenylene ether is too large, the reactivity with the epoxy group of the epoxy compound or the cyanate group of the cyanate compound tends to be too high, for example, the storage stability of the resin composition There is a risk of problems such as a decrease.

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

  Here, the average number of hydroxyl groups of the low molecular weight polyphenylene ether can be understood from the standard value of the product of the low molecular weight polyphenylene ether to be used. Specific examples of the average number of hydroxyl groups of the low molecular weight polyphenylene ether include the 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.

  The number average molecular weight of the low molecular weight polyphenylene ether can be specifically measured using, for example, gel permeation chromatography.

  Moreover, it is preferable that content of the said low molecular weight polyphenylene ether is 15-75 mass parts with respect to a total of 100 mass parts of the said low molecular weight polyphenylene ether, the said epoxy compound, and the said cyanate compound, and 25-50 masses. More preferably, it is a part. If the amount of the low molecular weight polyphenylene ether is too small, the excellent dielectric properties of the polyphenylene ether tend not to be maintained. If the amount is too large, the heat resistance of the cured product tends to be insufficient. That is, when the content of the low molecular weight polyphenylene ether is within the above range, the heat resistance of the cured product is sufficiently high, and the excellent dielectric properties of the polyphenylene ether can be exhibited.

  The epoxy compound is not particularly limited as long as it has an average of two or more epoxy groups in one molecule, and may be an epoxy resin. Specifically, for example, dicyclopentadiene type epoxy resin, bisphenol A type epoxy resin having bisphenol A skeleton, bisphenol F type epoxy resin having bisphenol F skeleton, phenol novolac type epoxy resin, naphthalene type epoxy resin having naphthalene skeleton And biphenyl type epoxy resins such as biphenyl aralkyl type epoxy resins. These may be used alone or in combination of two or more. Among these, bisphenol A type epoxy resin, biphenyl type epoxy resin, bisphenol F type epoxy resin, and naphthalene type epoxy resin are preferable from the viewpoint of good compatibility with the low molecular weight polyphenylene ether, bisphenol A type epoxy resin, And biphenyl aralkyl type epoxy resins are more preferably used. 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.

  Moreover, as said epoxy compound, the average number of epoxy groups per molecule (average number of epoxy groups) should just be 2 or more. Thus, when there are many epoxy groups, it is preferable from the point which the heat resistance of the hardened | cured material of the obtained resin composition increases. In addition, the average number of epoxy groups of the said epoxy compound here can be known from the specification value of the product of the said epoxy compound to be used. Specific examples of the number of epoxy groups in the epoxy compound include an average value of epoxy groups per molecule of all the epoxy compounds present in 1 mol of the epoxy compound.

  Moreover, it is preferable that content of the said epoxy compound is 15-75 mass parts with respect to a total of 100 mass parts of the said low molecular weight polyphenylene ether, the said epoxy compound, and the said cyanate compound, and is 25-50 mass parts. Preferably there is. When the amount of the cyanate compound is too small, the heat resistance of the cured product tends to be insufficient. Moreover, when there are too many said cyanate compounds, the influence of a cyanate compound will become large and there exists a tendency which cannot maintain the outstanding dielectric characteristic which polyphenylene ether has. That is, when the content of the cyanate compound is within the above range, the heat resistance of the cured product is sufficiently high, and the excellent dielectric properties of polyphenylene ether can be exhibited.

  The cyanate compound is not particularly limited as long as the cyanate group has an average of 2 or more in one molecule. Specifically, for example, 2,2-bis (4-cyanatophenyl) propane, bis (3,5-dimethyl-4-cyanatophenyl) methane, 2,2-bis (4-cyanatophenyl) ethane Or aromatic cyanate ester compounds such as derivatives thereof. These may be used alone or in combination of two or more.

  Moreover, as said cyanate compound, the average number of cyanate groups per molecule (average number of cyanate groups) should just be 2 or more. Thus, when there are many cyanate groups, it is preferable from the point which the heat resistance of the hardened | cured material of the obtained resin composition increases. In addition, the average cyanate group number of the said cyanate compound here can be known from the standard value of the product of the said cyanate compound to be used. Specific examples of the number of cyanate groups in the cyanate compound include an average value of epoxy groups per molecule of all the cyanate compounds present in 1 mole of the cyanate compound.

  Moreover, it is preferable that content of the said cyanate compound is 5-50 mass parts with respect to a total of 100 mass parts of the said low molecular weight polyphenylene ether, the said epoxy compound, and the said cyanate compound, and is 20-45 mass parts. Preferably there is. When the amount of the cyanate compound is too small, the heat resistance of the cured product tends to be insufficient. Moreover, when there are too many said cyanate compounds, the influence of a cyanate compound will become large and there exists a tendency which cannot maintain the outstanding dielectric characteristic which polyphenylene ether has. That is, when the content of the cyanate compound is within the above range, the heat resistance of the cured product is sufficiently high, and the excellent dielectric properties of polyphenylene ether can be exhibited.

  Moreover, as the low molecular weight polyphenylene ether, the epoxy compound, and the cyanate compound, a reaction product obtained by reacting the low molecular weight polyphenylene ether, the epoxy compound, and the cyanate compound in advance may be used. Specifically, the resin composition has a number average molecular weight of 500 to 2000, a low molecular weight polyphenylene ether having an average of 1.5 to 2 hydroxyl groups in one molecule, and an average of 2 to 2. A reaction product of an epoxy compound having three epoxy groups and a cyanate compound having two or more cyanate groups in one molecule, a phosphinate flame retardant, a polyphosphate flame retardant having a triazine skeleton, and It contains. By doing so, it is possible to further improve the heat resistance of the cured product by using a reaction product obtained by previously reacting PPE which tends to have low heat resistance with an epoxy compound and cyanate compound having high heat resistance. It is considered possible. Moreover, it is thought that the curing reaction of a low molecular weight polyphenylene ether, an epoxy compound, and a cyanate compound can be further accelerated | stimulated by using an epoxy compound and a cyanate compound together in that case.

  In addition, as described above, the resin composition contains a phosphinate flame retardant and a polyphosphate flame retardant having a triazine skeleton.

  The phosphinate flame retardant is not particularly limited. Specific examples include phosphinic acid metal salts such as aluminum dialkylphosphinic acid salts. As said phosphinate flame retardant, the said phosphinate flame retardant may be used independently and may be used in combination of 2 or more type.

  The polyphosphate flame retardant is not particularly limited as long as it is a polyphosphate having a triazine skeleton, and is used for enhancing flame retardancy. Since this polyphosphate flame retardant is a polymer, it is considered that not only the flame retardancy can be improved, but also hydrolysis resistance, heat resistance and the like can be improved. Moreover, it is thought that the said polyphosphate flame retardant can exhibit the carbonization promotion effect notably with respect to the said polyphenylene ether resin rather than the said epoxy resin. And it is thought that the carbonization layer formed by exhibiting the carbonization promotion effect can suppress the spread of combustible gas and heat, and can fully raise a flame retardance. Therefore, it is considered that the flame retardancy of the cured product of the obtained resin composition can be sufficiently enhanced by using the polyphosphate together with a predetermined amount or more of the polyphenylene ether resin.

  Specific examples of the polyphosphate flame retardant include melamine polyphosphate, melam polyphosphate, melem polyphosphate, and complex salts thereof. Among these, melamine polyphosphate is preferably used. Examples of the complex salt include those described in JP-A-10-306081.

  The pH of the polyphosphate flame retardant is preferably 4-7. When the pH of the polyphosphate flame retardant is too low, the curing reaction between the low molecular weight polyphenylene ether and the epoxy resin is inhibited, and the heat resistance of the cured product tends to be lowered. Moreover, when the pH of the polyphosphate flame retardant is too high, the material tends to be unstable or a by-product tends to be mixed in a large amount. The pH of the polyphosphate can be measured with a general pH meter.

  The polyphosphate flame retardant is specifically preferably, for example, having an average particle size of 10 μm or less, more preferably 5 μm or less.

  As described above, the polyphosphate flame retardant can be used without particular limitation as long as it is a polyphosphate having a triazine skeleton, and specifically, for example, JP-A-10-306081 What was prepared by the method of description, etc. can be used. Examples of the method for adjusting the pH of the polyphosphate flame retardant include a method for adjusting the mixing ratio of polyphosphoric acid and melamine, melam, melem, etc. in the method for producing polyphosphate. .

  Further, the contents of the phosphinate flame retardant and the polyphosphate flame retardant are such that the phosphorus atom content is 3.5% by mass or more based on the resin composition. . When there is too little content of the said phosphinate flame retardant and the said polyphosphate flame retardant, there exists a tendency which cannot fully raise the flame retardance of hardened | cured material. In addition, the content of the phosphinate flame retardant and the polyphosphate flame retardant is an amount such that the phosphorus atom content is 5% by mass or less with respect to the resin composition. The amount is preferably 4.5% by mass or less. When the content of the phosphinate flame retardant and the polyphosphate flame retardant is too large, the heat resistance and dielectric properties of the cured product tend to be reduced. There is a tendency that sufficient flame retardancy cannot be obtained.

  In addition, content of the said phosphorus atom is a ratio (mass%) with respect to the said resin composition, and can be computed from content of the phosphorus atom of the said phosphinate flame retardant and the said polyphosphate flame retardant to be used.

  The content ratio of the polyphosphate flame retardant to the phosphinate flame retardant (polyphosphate flame retardant / phosphinate flame retardant) is 0.25 to 2 in terms of mass ratio. preferable. If the content ratio is too low, the ratio of the phosphinate flame retardant increases, the curing reaction between the low molecular weight polyphenylene ether, the epoxy compound and the cyanate compound is inhibited, and the cured product has sufficient heat resistance. There is a tendency not to increase. Further, if the content ratio is too high, the ratio of the polyphosphate flame retardant increases, and if it is contained in an amount that can sufficiently increase the flame retardancy of the cured product, the dielectric constant of the cured product becomes too high. , The dielectric properties tend to decrease.

  Moreover, you may mix | blend a hardening | curing agent with the said resin composition. As the curing agent, those conventionally used in general can be used. Specific examples include amine curing agents such as primary amines and secondary amines, phenolic curing agents such as bisphenol A and bisphenol F, and acid anhydride curing agents. Among these, an amine curing agent is preferable from the viewpoint of improving curability, and specifically, diethyltoluenediamine is more preferable among the amine curing agents. The curing agent is preferably blended in an equivalent ratio of 0.1 to 0.5 equivalent with respect to the epoxy compound.

  Further, the resin composition may contain a curing accelerator together with the curing agent in order to promote a crosslinking reaction (curing reaction) between the low-molecular polyphenyl ether, the epoxy compound, and the cyanate compound. . Even if the curing accelerator is 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. In such a case, the curing catalyst is blended. Is preferred. 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, in the case of using an organometallic salt, 0.005 to a total of 100 parts by mass of the low molecular weight polyphenylene ether, the epoxy compound, and the cyanate compound. It is preferably 5 parts by mass.

  The polyphenylene ether resin composition may further contain a flame retardant other than the phosphinate flame retardant and the polyphosphate flame retardant as a flame retardant. Such a flame retardant can be used without any particular limitation.

  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 polyphenylene ether 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 an interlayer peel strength. Tend to be higher.

  The resin composition may be blended with additives such as a heat stabilizer, an antistatic agent, an ultraviolet absorber, a dye, a pigment, a lubricant and the like, as necessary, as long as the effects of the present invention are not impaired. .

  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 low molecular weight polyphenyl ether, the epoxy compound, the cyanate compound, and the like are introduced into an organic solvent and dissolved. At this time, heating may be performed as necessary. Furthermore, if necessary, by adding a curing agent, a curing catalyst, a flame retardant and an inorganic filler, using a ball mill, a bead mill, a planetary mixer, a roll mill, etc., and dispersing until a predetermined dispersion state, A varnish-like resin composition is prepared. The organic solvent is not particularly limited as long as it dissolves the low molecular weight polyphenyl ether, the epoxy compound, and the cyanate compound 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 produced, the type of the resin composition of the prepreg, etc. For example, the temperature is 170 to 220 ° C., the pressure is 3 to 4 MPa, and the time is 60 to 150. Can be minutes.

  The resin composition is excellent in the heat resistance and flame retardancy of the cured product while maintaining the excellent dielectric properties of polyphenylene ether. For this reason, the metal-clad laminated board using the prepreg obtained using the said resin composition is excellent in a dielectric characteristic, heat resistance, and a flame retardance. Moreover, since the polyphenylene ether contained in the resin composition has a low molecular weight, the resin composition has a low viscosity and a high fluidity. Therefore, the obtained prepreg is excellent in reliability capable of suppressing the occurrence of molding defects when manufacturing a metal-clad laminate or a printed wiring board using the metal-clad laminate.

  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 has excellent dielectric properties and has high heat resistance and flame retardancy.

  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.

<Examples 1-3, Comparative Examples 1-8>
[Preparation of resin composition]
In this example, each component used when preparing the resin composition will be described.

(Polyphenylene ether)
PPE: polyphenylene ether (MX-90 manufactured by SABIC Innovative Plastics, number average molecular weight Mn1000, average number of hydroxyl groups 1.7)
(Epoxy compound)
Biphenyl aralkyl type epoxy resin (Nippon Kayaku Co., Ltd. NH3000H, average epoxy group number 3.4)
Bisphenol A type epoxy resin (YD8125 manufactured by Tohto Kasei Co., Ltd., average number of epoxy groups 2)
(Cyanate compound)
2,2′-bis (4-cyanatophenyl) propane (LADC Japan Co., Ltd. BADCy, average cyanate group number 2)
(Phosphonate flame retardant)
Aluminum dialkylphosphinate (OP935 manufactured by Clariant Japan)
(Polyphosphate flame retardant with triazine skeleton)
Melamine polyphosphate (Melapur 200 manufactured by Ciba)
(Other)
Aluminum hydroxide (CL303M manufactured by Sumitomo Chemical Co., Ltd.)
Magnesium hydroxide (MGZ3 manufactured by Sakai Chemical Industry Co., Ltd.)
Zinc molybdate (KGM911C manufactured by SHERWIN Williams)
[Preparation method]
Polyphenylene ether was dissolved in toluene heated to 90 ° C. After adding an epoxy compound and a cyanate compound so that it might become the mixture ratio (mass part) of Table 1 to the obtained solution, it was made to melt | dissolve completely by stirring for 30 minutes. Furthermore, varnish-like resin composition (resin varnish) was obtained by adding other components such as phosphinate flame retardant and polyphosphate flame retardant and dispersing with a bead mill.

  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 120 to 160 ° C. for 3 to 7 minutes.

  Then, the obtained 6 prepregs were stacked one on top of another, and copper foils (GT-MP manufactured by Furukawa Circuit Foil Co., Ltd., thickness 35 μm) were disposed on both outer layers, and the temperature was 220 ° C. for 2 hours. The copper-clad laminate having a thickness of 0.75 mm was obtained by heating and pressing under the condition of a pressure of 3 MPa.

<Example 4>
Example 4 uses a bisphenol A type epoxy resin instead of a biphenyl aralkyl type epoxy resin, and further uses a reaction product obtained by reacting a polyphenylene ether with an epoxy compound and a cyanate compound in advance. The process is the same as in Example 1 except that the above is performed.

  Specifically, the reaction product was prepared as follows. 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, a reaction product was prepared by pre-reacting (prereacting) the low molecular weight polyphenylene ether with the epoxy compound and the cyanate compound.

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

[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.

[Dielectric constant]
Using a cavity resonator “CP461” manufactured by Kanto Electronics Application Development Co., Ltd., the dielectric constant of a copper clad laminate at 2 GHz was measured.

[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.

  These results are shown in Table 1.

  In Table 1, the phosphorus atom content is the ratio (% by mass) to the resin composition, and the phosphorus atom content of the phosphinate flame retardant and the polyphosphate flame retardant used. It is calculated from

  As can be seen from Table 1, a low molecular weight polyphenylene ether having a number average molecular weight of 500 to 2000 and an average of 1.5 to 2 hydroxyl groups in one molecule and an average of 2 or more epoxy groups in one molecule. It contains an epoxy compound, a cyanate compound having an average of two or more cyanate groups in one molecule, a phosphinate flame retardant, and a polyphosphate flame retardant having a triazine skeleton, and the phosphorus atom content is When the resin composition of 3.5% by mass or more is used (Examples 1 to 3), the excellent dielectric properties of polyphenylene ether (PPE) compared to other cases (Comparative Examples 1 to 8) While maintaining the characteristics, a prepreg having excellent flame retardancy and high Tg was obtained.

  Further, when a resin composition containing a reaction product obtained by reacting them in advance instead of the low molecular weight polyphenylene ether, epoxy compound and cyanate compound (Example 4) is used, Examples 1 to 3 Similarly, as compared with Comparative Examples 1 to 8, a prepreg having excellent flame retardancy and high Tg was obtained while maintaining the excellent dielectric properties of polyphenylene ether (PPE).

Claims (9)

Low molecular weight polyphenylene ether having a number average molecular weight of 500 to 2000 and having an average of 1.5 to 2 hydroxyl groups in one molecule;
An epoxy compound having an average of two or more epoxy groups in one molecule;
A cyanate compound having an average of two or more cyanate groups in one molecule;
A phosphinate flame retardant,
Containing a polyphosphate flame retardant having a triazine skeleton,
Content of phosphorus atom is 3.5 mass% or more, The resin composition characterized by the above-mentioned.   Each content of the low molecular weight polyphenylene ether, the epoxy compound, and the cyanate compound is 15 to 75 parts by mass with respect to a total of 100 parts by mass of the low molecular weight polyphenylene ether, the epoxy compound, and the cyanate compound, respectively. It is 15-75 mass parts, 5-50 mass parts, The resin composition of Claim 1.   The resin composition according to claim 1 or 2, wherein the polyphosphate flame retardant has a pH of 4 to 7.   The resin composition according to claim 1, wherein the polyphosphate flame retardant is melamine polyphosphate. Low molecular weight polyphenylene ether having a number average molecular weight of 500 to 2,000 having an average of 1.5 to 2 hydroxyl groups in one molecule, an epoxy compound having an average of 2 to 2.3 epoxy groups in one molecule, and 1 A reaction product of a cyanate compound having two or more cyanate groups in the molecule;
A phosphinate flame retardant,
Containing a polyphosphate flame retardant having a triazine skeleton ,
Content of phosphorus atom is 3.5 mass% or more, The resin composition characterized by the above-mentioned . The resin composition according to any one of claims 1 to 5, wherein a content ratio of the polyphosphate flame retardant to the phosphinate flame retardant is 0.25 to 2 in terms of mass ratio. A prepreg obtained by impregnating a fibrous base material with the resin composition according to any one of claims 1 to 6 . A metal-clad laminate obtained by laminating a metal foil on the prepreg according to claim 7 and heating and pressing. A printed wiring board manufactured using the prepreg according to claim 7 .