JP2000273298A - Flame-retardant, hardening resin composition - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a hardening resin composition that is imparted sufficient flame retardancy despite containing no halogen in the composition, in other words, halogen-free. SOLUTION: The resin composition comprises (i) 30-80 wt.% of (A) a polyphenylene ether resin and (B-1) a melamine-modified phenol-formaldehyde resin, 10-70 wt.% of (C) a phosphoric ester, and (ii) 2-50 wt.% of (D) ammonium phosphate or 10-70 wt.% of (E) a silicone-modified melamine resin.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

TECHNICAL FIELD The present invention relates to a halogen-free flame-retardant curable resin composition and a cured product obtained by curing the same. Further, the present invention relates to a curable composite material comprising the curable resin composition and a substrate, a cured product thereof (cured composite material), a laminate comprising the cured product and a metal foil, and a copper foil with resin.

[0002] The halogen-free flame-retardant curable resin composition of the present invention exhibits excellent chemical resistance, dielectric properties, heat resistance and flame retardancy after curing, and is used in fields such as the electric industry, the space and aircraft industries. Can be used as a dielectric material, an insulating material, a heat-resistant material, a structural material, and the like.

[0003]

2. Description of the Related Art In recent years, there has been a remarkable trend toward miniaturization and high-density mounting methods in the field of electronic devices for communication, consumer use, industrial use, and the like, and accordingly, materials have become more excellent. Heat resistance, dimensional stability, and electrical properties are being demanded. For example, as a printed wiring board, a copper-clad laminate made of a thermosetting resin such as a phenol resin or an epoxy resin has been used. Although these have various performances in a well-balanced manner, they have a drawback that electrical characteristics, particularly, dielectric characteristics in a high frequency range are poor. As a new material for solving this problem, polyphenylene ether has recently attracted attention, and application to copper-clad laminates has been attempted.

For example, Japanese Unexamined Patent Publication (Kokai) No. 61-287739 discloses a laminated plate obtained by curing a resin composition containing polyphenylene ether and triallyl isocyanurate and / or triallyl cyanurate.
No. 7567 discloses a curable resin composition containing a polyphenylene ether modified by reaction with an unsaturated carboxylic acid or an acid anhydride and triallyl isocyanurate and / or triallyl cyanurate, and a laminate obtained using the same. Are disclosed in JP-A-64-69628 and JP-A-64-69628.
No. 69629, JP-A No. 1-113425, 1-11
No. 3426 discloses a curable resin composition containing a polyphenylene ether containing a triple bond or a double bond and triallyl isocyanurate and / or triallyl cyanurate.

Further, as a material obtained by combining polyphenylene ether and epoxy, for example, Japanese Patent Publication No. 64-32
Japanese Patent Application Laid-Open No. 2-1352 discloses a curable resin composition containing polyphenylene ether, various epoxy resins such as bisphenol A type epoxy resin and novolak type epoxy resin, and various curing agents such as phenols and amines.
Japanese Patent Application Laid-Open No. 2-166115 discloses a curable resin composition comprising a polyphenylene ether modified by a reaction with an unsaturated carboxylic acid or an acid anhydride, a polyepoxy compound, and a curing catalyst for epoxy. A curable resin composition comprising a processed polyphenylene ether, a polyepoxy compound, and a curing catalyst for epoxy is disclosed.

The above composition is used for various electronic materials such as a copper-clad laminate. In this case, the flame retardancy of the resin is an essential property from the viewpoint of product safety. Heretofore, organic halogen compounds such as aromatic bromides and brominated epoxies have been used as a method for making resins flame-retardant. However, organic halogen compounds may generate highly toxic dioxins during combustion, and their use has recently been limited. In order to cope with such a situation, attempts have been made to impart halogen-free resin with flame retardancy, but until now, halogen-free resin has sufficient flame retardancy (for example, UL94 standard). V
−0) was difficult to impart.

[0007]

DISCLOSURE OF THE INVENTION The present invention has been made to solve the above-mentioned problems, and has a composition containing no halogen, that is, a curable composition which is halogen-free and has sufficient flame retardancy. A resin composition, a cured product thereof, a curable composite material comprising the curable resin composition and a base material, a cured product thereof (cured composite material), a laminate comprising the cured product and a metal foil, and a resin-attached metal foil. To provide.

[0008]

The present invention firstly provides:
(I) (A) a polyphenylene ether-based resin, and (B)
-1) Melamine-modified phenol formaldehyde resin:
30 to 80% by weight, (C) phosphate: 10 to 70
% By weight, and (ii) ammonium phosphate (D):
A curable resin composition containing 50% by weight or (E) a silicone-modified melamine resin: 10 to 70% by weight.

Second, (i) (A) a polyphenylene ether-based resin, (B-1) a melamine-modified phenol formaldehyde resin, and (B-2) an epoxy resin:
80% by weight, (C) phosphate: 10-70% by weight, and (ii) (D) ammonium phosphate: 2-50
% By weight, or (E) silicone-modified melamine resin: 1
0 to 70% by weight.

Third, a cured product obtained by curing the first and second curable resin compositions is provided. Fourth, a curable composite material comprising the first and second curable resin compositions and a base material, wherein the base material is contained at a ratio of 5 to 90% by weight. I will provide a.

Fifth, a cured composite material obtained by curing the fourth curable composite material is provided. Sixthly, a laminate comprising the fifth cured composite material and a metal foil is provided. Seventh
In addition, the present invention provides a resin-attached metal foil characterized in that the first and second curable resin composition films are formed on one surface of the metal foil.

Hereinafter, the present invention will be described in more detail. Preferred examples of the polyphenylene ether resin (A) used in the present invention include poly (2,6-dimethyl-1,4-phenylene ether) obtained by homopolymerization of 2,6-dimethylphenol, and poly (2,6). -Dimethyl-1,4-phenylene ether) styrene graft copolymer, 2,6
-Copolymer of dimethylphenol and 2,3,6-trimethylphenol, copolymer of 2,6-dimethylphenol and 2-methyl-6-phenylphenol, presence of 2,6-dimethylphenol and polyfunctional phenol compound Polyfunctional polyphenylene ether resin obtained by polymerization under
For example, JP-A-63-301222, JP-A-1-2
General formula (A) as disclosed in JP-A-97428
And copolymers containing the units of (B).

With respect to the molecular weight of the polyphenylene ether resin described above, the viscosity number ηsp / C measured with a 0.5 g / dl chloroform solution at 30 ° C. is 0.1 to 1.
Those in the range of 0 can be preferably used. Further, the polyphenylene ether-based resin referred to in the present invention includes a modified product. Such a modified product is specifically a polyphenylene ether resin containing an unsaturated group (Japanese Patent Application Laid-Open No. 64-69).
No. 628, JP-A-1-113425, JP-A-1-11
No. 3426), and a reaction product of a polyphenylene ether resin with an unsaturated carboxylic acid and / or acid anhydride.

The above (A) polyphenylene ether-based resin is the sum of (A) and (B-1), or (A)
It is preferable to mix 10 to 70 parts by weight based on 100 parts by weight of the total of (B-1) and (B-2).
Examples of the (B-1) melamine-modified phenol formaldehyde resin used in the present invention include phenol,
Co-condensates of phenols such as cresol, xylenol, butylphenol, nonylphenol and melamines such as melamine, benzoguanamine, acetoguanamine and formguanamine, and formaldehyde; And a mixture of a phenol formaldehyde condensate and a melamine formaldehyde condensate, including those modified with tung oil, isomerized linseed oil and the like.

In these melamine-modified phenol formaldehyde resins, the blending ratio of melamines, that is, the degree of modification leads to a slight increase in the nitrogen content, which greatly affects the flame retardancy and various properties as a laminate. In order to impart sufficient flame retardancy to the resin composition and satisfy various characteristics required for the laminate, the nitrogen content in the melamine-modified phenol formaldehyde resin is 2 to 3.
It is desirably 0% by weight.

The (B-2) epoxy resin used in the present invention may have a low molecular weight (including a monomer) or a high molecular weight as long as it contains two or more epoxy groups in one molecule. These are used alone or in combination of two or more. Typical examples of these are
Glycidyl ether type epoxy resin obtained by reaction of phenols or alcohols with epichlorohydrin, glycidyl type epoxy resin obtained by reaction of amines or cyanuric acid with epichlorohydrin, obtained by oxidation of double bond [For details of these, see “Epoxy Resin Handbook” edited by Masaki Shinbo, Nikkan Kogyo Shimbun, 1987].

The total amount of (A) polyphenylene ether resin and (B-1) melamine-modified phenol formaldehyde resin, (A) polyphenylene ether resin, (B-1) melamine-modified phenol formaldehyde resin, and (B-2) ) The total amount of epoxy resin is
It is desirable to mix them in a ratio of 30 to 80% by weight based on the total amount of each component of (A) to (E).

The phosphoric acid ester (C) which can be used in the present invention includes phenyl or aryl ester of phosphoric acid, phenyl or aryl ester of phosphonic acid, phenyl or aryl ester of phosphinic acid, trialkylphosphine oxide, triphenyl Examples include phosphine oxide and triarylphosphine oxide.

Specific examples of such phosphate compounds include, for example, triphenyl phosphate, tricresyl phosphate, trixylenol phosphate, cresyl diphenyl phosphate, xylenol diphenyl phosphate, triisopropylphenyl phosphate, trinonyl phosphate, and the like. Nonylphenyl diphenyl phosphate and the like can be mentioned, and these can be used alone or in combination of two or more. These phosphate esters are 10 to 70% by weight, preferably 30 to 70% by weight, more preferably 5 to 70% by weight, based on the sum of the components (A) to (E).
It is blended at a ratio of 0 to 70% by weight. 10% by weight
If it is less than 70%, the flame retardancy is insufficient, and if it exceeds 70% by weight, the electrical properties and other physical properties deteriorate.

As the (D) ammonium phosphate used in the present invention, specific compounds include, for example, monoammonium phosphate, diammonium phosphate, triammonium phosphate, ammonium polyphosphate and the like. Alternatively, two or more kinds can be used as a mixture. Ammonium phosphate is blended in order to enhance the flame retardant effect. The compounding ratio of ammonium phosphate is 2 to 50% by weight, preferably 10 to 50% by weight, more preferably 30 to 50% by weight based on the total amount of each component of (A) to (D).
５０50% by weight. If the amount is less than 2% by weight, sufficient flame retardancy cannot be obtained, and if it exceeds 50% by weight, solder heat resistance and other physical properties deteriorate.

The (E) silicone-modified melamine resin used in the present invention is a resin obtained by co-condensing melamines and silicone. Melamines used herein include melamine resins containing methylol groups by condensation of melamine and aldehydes, benzoguanamine resins also containing methylol groups, butylated melamine resins whose methylol groups are etherified with butanol, and butylated benzoguanamines. Resins and the like are used, and these are used alone or in combination of two or more.

Examples of the silicone include organosiloxanol containing a hydroxyl group bonded to a silicon atom and organoalkoxysilane (or siloxane) containing an alkoxy group bonded to a silicon atom. These may be used alone or in combination of two or more. These are used as a mixture. The organo group may be only a methyl group, but preferably contains a phenyl group together with the methyl group in order to improve heat resistance.

The reaction between the melamine and the silicone is carried out in a solvent such as toluene at a reaction temperature of 100 to 120 ° C., and the condensation is carried out by dehydration of a methylol group and a silanol group. These silicone-modified melamine resins are used in an amount of 10 to 70% by weight, preferably 3 to 70% by weight based on the total amount of the components (A) to (E).
0 to 70% by weight, more preferably 50 to 70% by weight. If the amount is less than 10% by weight, there is no effect in improving the flame retardancy. If the amount exceeds 70% by weight, problems such as insufficient punching workability when a laminate is formed arise.

In the present invention, the above components (A) to (D) or (A) to (E) are essential components, but other components can be added as long as the object of the present invention is not adversely affected. Examples of the other components that can be added include a curing agent and a curing accelerator. These will be described below. As the curing agent, compounds usually used for curing epoxy resins, for example, dicyandiamide, aromatic amines and the like as amines, phenol novolak resins, cresol novolak resins, bisphenol A and the like as phenol curing systems, Are used alone or in combination of two or more. Further, as a curing agent, a crosslinkable compound such as diallyl phthalate, divinylbenzene, a polyfunctional acryloyl compound, a polyfunctional methacryloyl compound, a polyfunctional isocyanate, an unsaturated polyester, triallyl isocyanurate, triallyl cyanurate, polybutadiene,
Styrene-butadiene, styrene-butadiene-styrene and the like can also be mentioned, and these can be used alone or as a mixture of two or more. It is also possible to use a mixture of two or more compounds which are usually used for curing an epoxy resin and a crosslinkable compound.

Examples of the curing accelerator include curing accelerators and radical initiators usually used for epoxy resins. The former includes, for example, imidazole compounds, and the latter includes ordinary peroxides such as perhexin 25B. Is mentioned. Further, the curable resin composition of the present invention,
In addition to those mentioned above, fillers and additives can be blended and used in amounts not to impair the original properties, for the purpose of further imparting desired performance according to the use. Examples of such a filler include carbon black, barium titanate, glass beads, and hollow glass spheres. In addition, examples of the additive include an antioxidant, a heat stabilizer, an antistatic agent, a plasticizer, a pigment, a dye, and a colorant. Further, (A), (B-1), (B
It is also possible to mix one or more thermoplastic resins and thermosetting resins other than -2).

The above (A) to (D) or (A) to
As a method for mixing the components (E), a solution mixing method in which each component is uniformly dissolved or dispersed in a solvent, a melt blending method in which the components are heated by an extruder or the like can be used. Solvents used for solution mixing include benzene,
Aromatic solvents such as toluene and xylene, and tetrahydrofuran are used alone or in combination of two or more.

The curable resin composition of the present invention may be formed into a desired shape in advance according to its use. The molding method is not particularly limited. Usually, a casting method in which the resin composition is dissolved in the above-described solvent and molded into a desired shape, or a heat melting method in which the resin composition is heated and melted to form a desired shape is used. The cured product of the present invention is obtained by curing the curable resin composition described above. The method of curing is arbitrary, and a method using heat, light, an electron beam, or the like can be employed.

When curing by heating, the temperature is as follows:
Depending on the type of radical initiator, 80-30
0 ° C, more preferably in the range of 120 to 250 ° C. The time is about 1 minute to 10 hours, more preferably 1 minute to 5 hours. Further, this curable resin composition can be used by being bonded to a metal foil and / or a metal plate as in the case of a cured composite material described later.

Next, the fourth and fifth curable composite materials of the present invention and their cured products will be described. Fourth Embodiment of the Present Invention
The curable composite material is characterized by comprising the first or second curable resin composition of the present invention and a base material. Examples of the base material used in the present invention include various glass cloths such as roving cloth, cloth, chopped mat, and surfacing mat, asbestos cloth, metal fiber cloth and other synthetic or natural inorganic fiber cloths, wholly aromatic polyamide fibers, wholly aromatic fibers. Or non-woven fabric obtained from liquid crystal fiber such as aromatic polyester fiber or polybenzozar fiber, or woven or non-woven fabric obtained from synthetic fiber such as polyvinyl alcohol fiber, polyester fiber or acrylic fiber, natural fiber such as cotton cloth, linen cloth or felt Natural cellulose-based cloths such as cloth, carbon fiber cloth, kraft paper, cotton paper, and paper-glass mixed fiber paper may be used alone or in combination of two or more.

In the present invention, the proportion occupied by the substrate is 5 to 90 parts by weight, more preferably 10 to 80 parts by weight, further preferably 20 to 70 parts by weight, based on 100 parts by weight of the curable composite material. . When the proportion of the base material is less than 5 parts by weight, the dimensional stability and strength after curing of the composite material are insufficient, and when the proportion of the base material is more than 90 parts by weight, the dielectric properties of the composite material are inferior, which is not preferable. .

In the curable composite material of the present invention, if necessary, a coupling agent can be used for the purpose of improving the adhesion at the interface between the resin and the substrate. As the coupling agent, general ones such as a silane coupling agent, a titanate coupling agent, an aluminum-based coupling agent, and a zircoaluminate coupling agent can be used. As a method for producing the curable composite material of the present invention, for example, the components (A) to (D) or the components (A) to (E) described in the first section of the present invention and other components as necessary. Is uniformly dissolved or dispersed in the above-mentioned aromatic or ketone-based solvent or a mixed solvent thereof, impregnated into a substrate, and then dried.

The impregnation is performed by dipping (dipping), coating or the like. The impregnation can be repeated multiple times as necessary, and in this case, the impregnation can be repeated using multiple solutions having different compositions and concentrations to finally adjust the desired resin composition and resin amount It is. The fifth cured composite material of the present invention is obtained by curing the curable composite material thus obtained by a method such as heating. The manufacturing method is not particularly limited, for example, a plurality of the curable composite material,
The layers are adhered to each other under heat and pressure, and at the same time, thermosetting is performed to obtain a cured composite material having a desired thickness. Moreover, it is also possible to obtain a cured composite material having a new layer configuration by combining the cured composite material once cured by adhesion and the curable composite material. Lamination molding and curing are usually performed simultaneously using a hot press or the like, but both may be performed independently. That is, the uncured or semi-cured composite material obtained by lamination molding in advance can be cured by heat treatment or another method.

The molding and curing are performed at a temperature of 80 to 300.
° C, pressure: 0.1 to 1000 kg / cm ² , time: 1 minute to 10 hours, more preferably temperature: 150 to 2
The reaction can be performed at 50 ° C., pressure: 1 to 500 kg / cm ² , time: 1 minute to 5 hours. The sixth laminate of the present invention comprises the fifth cured composite material of the present invention and a metal foil. Examples of the metal foil used here include a copper foil and an aluminum foil. The thickness is not particularly limited, but is in the range of 5 to 200 μm, more preferably 5 to 105 μm.

The method for producing the laminate of the present invention includes:
For example, the curable composite material described above as the fourth of the present invention and a metal foil and / or a metal plate are laminated in a layer structure according to the purpose, and the respective layers are adhered under heat and pressure, and simultaneously thermoset. Methods can be mentioned. In the laminate of the present invention, the curable composite material and the metal foil are laminated in an arbitrary layer configuration. The metal foil can be used as both a surface layer and an intermediate layer. In addition to the above, lamination and curing may be repeated a plurality of times to form a multilayer.

An adhesive can be used for bonding the metal foil. Examples of such an adhesive include, but are not particularly limited to, epoxy-based, acrylic-based, phenol-based, and cyanoacrylate-based adhesives. The lamination molding and curing can be performed under the same conditions as in the fifth aspect of the present invention. Finally, the seventh metal foil with resin of the present invention will be described. The resin-attached metal foil of the present invention comprises the first or second curable resin composition of the present invention and a metal foil. As the metal foil used here, for example,
Copper foil, aluminum foil and the like can be mentioned. Although the thickness is not particularly limited, it is 5 to 200 μm, more preferably 5 to 200 μm.
The range is 105 μm.

The method for producing the resin-attached metal foil of the present invention is not particularly limited.
After uniformly dissolving or dispersing the component (D) or the components (A) to (E) and, if necessary, other components in a solvent such as an aromatic or ketone-based solvent or a mixed solvent thereof, and applying the solution to a metal foil. Drying method is mentioned. The application can be repeated multiple times as necessary, and in this case, the application can be repeated using multiple solutions with different compositions and concentrations to finally adjust the desired resin composition and resin amount It is.

[0037]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Next, the present invention will be described with reference to embodiments. In the following Examples and Comparative Examples, “parts” means “parts by weight”.

[0038]

Reference Example 1 A four-necked flask equipped with a condenser was charged with 126 g of melamine and 243 g of 37% formalin, adjusted to PH9 by adding triethylamine, heated to 90 ° C. with stirring, and reacted at this temperature for 30 minutes. I let it.
Next, 188 g of phenol and 308 g of 37% formalin were added thereto and reacted for 2 hours by a reflux reaction, followed by dehydration under reduced pressure to obtain a melamine-modified phenol formaldehyde resin.

[0039]

[Reference Example 2] 600 g of butylated melamine and organosiloxanol [(OH) were placed in a four-necked flask equipped with a condenser.
_{2 SiPh-O-SiMe 2 -O} -SiPh (OH) -
O-SiMe ₂ (OH)] was reacted at 120 ° C. for 2 hours in a toluene reflux to obtain a silicone-modified melamine resin.

[0040]

Example 1 Poly (2,500) having a viscosity number ηsp / C of 0.54 measured in a chloroform solution of 0.5 g / dl at 30 ° C.
6-dimethyl-1,4-phenylene ether) 15 parts,
45 parts of melamine-modified phenol formaldehyde resin synthesized in Reference Example 1, cresyl diphenyl phosphate 2
5 parts of ammonium polyphosphate and 5 parts of ammonium polyphosphate were dissolved or dispersed in toluene to prepare a varnish.
/ M ² of glass cloth was immersed for impregnation, and dried in an air oven to obtain a curable composite material. Next, six sheets are laminated so that the thickness after curing becomes about 0.8 mm, and a copper foil having a thickness of 35 μm is placed on both sides thereof at 180 ° C. and 40 k.
It was molded and cured using a press molding machine at g / cm ² for 90 minutes.

With respect to the laminate obtained here, UL94
When a flammability test was performed based on the standard, it was V-0.

[0042]

Examples 2 to 12 A laminate was prepared and flammability was measured in the same manner as in Example 1, except that the number of parts of each component of the curable resin composition was changed as shown in Table 1. V-
It became 0.

[0043]

Example 13 A varnish was prepared in the same manner as in Example 1, and this was applied to a copper foil having a thickness of 18 μm with a bar coater so that the resin layer had a thickness of 50 μm. A copper foil was produced. Next, two pieces of the resin-attached copper foil are superimposed, and heated at 180 ° C. and 40 kg / cm ² for 9 hours.
It was molded and cured using a press molding machine for 0 minutes.

With respect to the laminate obtained here, UL94
When a flammability test was performed based on the standard, it was V-0. Table 1 summarizes the results of Examples 1 to 13.

[0045]

[Table 1]

[0046]

[Comparative Example 1] The compounding number of tricresyl phosphate was 2
A laminate was prepared and the flammability was measured in the same manner as in Example 1 except that the number of parts of ammonium polyphosphate was changed to 0 part and the amount of ammonium polyphosphate was changed to 1 part.

[0047]

Comparative Examples 2 to 6 A laminated body was prepared and flammability was measured in the same manner as in Comparative Example 1 except that the number of parts of each component of the curable resin composition was changed as shown in Table 2. The result was obtained.

[0048]

Comparative Example 7 The number of parts of tricresyl phosphate was 2
A copper foil with a resin was prepared and the flammability was measured in the same manner as in Example 13 except that the mixing number of the ammonium polyphosphate was changed to 0 part and the mixing amount of the ammonium polyphosphate was changed to 1 part. The results of Comparative Examples 1 to 7 are collectively shown in Table 2.

[0049]

[Table 2]

[0050]

According to the present invention, a curable resin composition which is halogen-free and has sufficient flame retardancy (V-0 according to UL94 standard), a cured product thereof, a curable resin composition and a substrate A curable composite material, a cured product thereof (cured composite material), a laminate comprising the cured product and a metal foil, and a metal foil with a resin are provided.

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Claims (7)

[Claims] 1. (i) (A) a polyphenylene ether-based resin and (B-1) a melamine-modified phenol formaldehyde resin: 30 to 80% by weight, (C) a phosphate ester: 10 to 70% by weight, and (ii) A curable resin composition containing (D) ammonium phosphate: 2 to 50% by weight, or (E) silicone-modified melamine resin: 10 to 70% by weight. 2. (i) (A) a polyphenylene ether-based resin, (B-1) a melamine-modified phenol formaldehyde resin, and (B-2) an epoxy resin: 30 to 80% by weight, and (C) a phosphate ester: 10 -70% by weight, and (ii) (D) ammonium phosphate: 2-50% by weight;
Or (E) a silicone-modified melamine resin: 10 to 70
% By weight of the curable resin composition. 3. A cured product obtained by curing the curable resin composition according to claim 1 or 2. 4. A curable composite material comprising the curable resin composition according to claim 1 and a substrate, wherein the substrate is 5 to 5.
A curable composite material containing 90% by weight. 5. A cured composite material obtained by curing the curable composite material according to claim 4. 6. A laminate comprising the cured composite material according to claim 5 and a metal foil. 7. A metal foil with resin, wherein a film of the curable resin composition according to claim 1 or 2 is formed on one surface of the metal foil.