JP2000017146A - Thermosetting resin composition and its cured product - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain the subject thermosetting resin composition that has excellent curing properties and can give cured products of excel-lent resistance to heat and moisture by using a resin having the benzoxazine rings and a phenolic resin bearing primary amino groups. SOLUTION: (A) A benzoxazine ring-bearing resin of the formula [R1 is an alkyl, a cyclohexyl, or (an alkyl ox alkoxysubstituted) phenyl] and (B) a phenolic resin bearing a primary group (for example, a phenol novolak resin into which amine groups are introduced, or aniline or a substituted aniline structure is introduced into a part of a phenol novolak structure) are used, preferably at a weight ratio of A/B=95/5-60/40. The resin of the component A is prepared by adding a mixture of a hydroxyl group-bearing compound and a primary amine to hot formalin solution to allow them to react with each other at 70-110 deg.C for 30-150 minutes.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

TECHNICAL FIELD The present invention relates to a laminate, an adhesive,
The present invention relates to a thermosetting composition and a cured product having excellent heat resistance and moisture resistance used for molding materials, sealing materials, composite materials, and the like.

[0002]

2. Description of the Related Art Laminates in the fields of electrical equipment and electronic components,
Phenolic resins and epoxy resins are used for molding materials, sealing materials, adhesives, paints and the like. In these fields, there is a strong demand for smaller and lighter weight, higher performance, higher density, and higher reliability.
High heat resistance is required.

[0003] A resin composition comprising a resin having a dihydrobenzoxazine ring and a resin having a phenolic hydroxyl group blended with a resin having excellent low hygroscopicity and high heat resistance is known (JP-A-8-183855, JP-A-9-1983). -272786). The resin composition has a lower curing rate than the phenol resin or the epoxy resin, and is an obstacle to improving the productivity.

[0004]

SUMMARY OF THE INVENTION The present invention provides a curable resin composition capable of providing a cured product having excellent curability, heat resistance and moisture resistance.

[0005]

The gist of the present invention is that of the general formula (1)

[0006]

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A thermosetting resin composition comprising a resin having a benzoxazine ring represented by the formula (I) and a phenol resin having a primary amino group, and a thermosetting resin composition obtained by curing the thermosetting resin composition. A cured resin product.

Further, a composite molding material containing the thermosetting resin composition and at least one of an inorganic filler and a fiber material, and a print formed by bonding and molding the composite molding material and a conductive pattern Provide a wiring board.

Further, the present invention provides a prepreg obtained by impregnating a base material with a varnish containing the thermosetting resin composition and then drying, and a metal foil-clad laminate obtained by laminating and molding the prepreg and a metal foil. I do.

[0010]

DETAILED DESCRIPTION OF THE INVENTION In the present invention, the general formula (1)

[0011]

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The resin having a dihydrobenzoxazine ring represented by the formula:

[0013]

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It can be obtained by the reaction shown in the above.

That is, it can be synthesized by reacting a compound having at least one unsubstituted phenolic hydroxyl group at the ortho position with a primary amine and formalin. The resin having a dihydrobenzoxazine ring is disclosed in U.S. Pat.
As disclosed in US Pat. No. 5,152,939, a ring-opening polymerization reaction is caused by heating to generate a phenolic hydroxyl group.
Form a crosslinked structure.

Examples of the compound having a phenolic hydroxyl group include a phenol novolak resin, a resol resin,
Phenolic resins such as xylene-modified phenolic resin, xylylene-modified phenolic resin, alkylphenolic resin, melamine-modified phenolic resin, polybutadiene-modified phenolic resin or bis (2-hydroxyphenyl) methane, bis (4-hydroxyphenylmethane), 4,
4'-dihydroxydiphenyl sulfone, 1,1-bis (4-hydroxyphenyl) ethane, p, p'-isopropylidene biphenol (bisphenol A), 2,2
-Bis [4- (4-hydroxyphenoxy) phenyl]
Bisphenol compounds such as propane, bisphenol compounds such as 4,4'-bisphenol, tris (4-hydroxyphenyl) methane, trisphenol compounds such as 1,1,1-tris (4-hydroxyphenyl) ethane, tetraphenol compounds, etc. Can be mentioned.

As the primary amine, alkylamine, cyclohexylamine, aniline and substituted aniline can be used. When an aliphatic amine is used, the obtained resin is quickly cured, but the heat resistance of the cured product is slightly inferior, and when an aromatic amine such as aniline is used, the heat resistance of the obtained cured product is improved, but the curability is slow. Become.

The resin of the present invention can be synthesized by adding a mixture of a compound having a hydroxyl group and a primary amine to heated formalin and reacting the mixture at a temperature of 70 to 110 ° C. for 30 to 150 minutes.

The phenolic resin having a primary amino group of the present invention is a compound in which a phenolic hydroxyl group and a primary amino group are in the same molecule, and an amine group in a phenol novolak resin described in JP-A-5-105734. A compound having an aniline or substituted aniline structure in a part of the phenol novolak structure described in JP-A-7-18060 is effective.

In the present invention, the curability can be remarkably promoted by using a phenol resin having a primary amino group which promotes the ring opening reaction of the resin having a dihydrobenzoxazine ring. In addition, the cured product properties of the resin composition of the present invention have low water absorption and high heat resistance, high glass transition temperature, high strength, and flame retardancy equivalent to or higher than those of the conventional resin composition having a dihydrobenzoxazine ring. Can be granted. In addition, the cured resin of the present invention is crosslinked and cured by a ring opening reaction,
There are no by-products during the reaction, and voids hardly remain in the cured product.

The optimum compounding ratio of the resin having a dihydrobenzoxazine ring to the phenol resin having a primary amino group is 95/5 to 60/40 (weight ratio). If the ratio is out of this range, the curing properties deteriorate.

The curing rate of the curable resin composition of the present invention can be increased by using a compound capable of accelerating the ring opening reaction of the dihydrobenzoxazine ring. The compound includes benzylmethylamine,
Amine compounds such as diaminodiphenyl ether, organic phosphorus compounds such as triphenylphosphine, boron trifluoride amine complex, dicyandiamide and derivatives thereof, and compounds having a phenolic hydroxyl group are effective. In particular, when the phenolic hydroxyl group and the primary amino group are in the same molecule, the effect is remarkable.

The resin composition of the present invention comprises an epoxy resin,
A thermosetting resin such as a bismaleimide resin or a flexible agent such as an elastomer, gel particles, or rubber can be used in combination. Examples of the epoxy resin include bisphenol epoxy resin, novolak epoxy resin, cresol novolak epoxy resin, polyphenol epoxy resin, polyglycol epoxy resin, alicyclic epoxy resin, halogenated epoxy resin, and the like. The bismaleimide resin is not particularly limited. For example, 4,4'-diphenylmethane bismaleimide or 2,2-bis [4- (4-
When (maleimidophenoxy) phenyl] propane is used, a sufficient crosslinking density can be ensured.

The thermosetting resin composition of the present invention may contain an elastomer to improve the brittleness of the resin. Examples of the elastomer include, but are not particularly limited to, an elastomer in which a part of the main chain structural units are cross-linked with each other, a thermosetting resin having a dihydrobenzoxazine ring, and phenol formed by opening a dihydrobenzoxazine ring. Liquid elastomers having a functional group capable of reacting with a hydroxyl group are preferred.

In the case of an elastomer in which a part of the main chain structural units are cross-linked with each other, an acrylonitrile-butadiene copolymer elastomer is particularly preferably used.

Further, a thermosetting resin having a dihydrobenzoxazine ring in the elastomer and a phenolic hydroxyl group generated by ring opening of the dihydrobenzoxazine ring can react with a functional group such as an epoxy group, a hydroxyl group or a carboxyl group. Those having a functional group having a high solubility parameter such as a group are particularly preferred. In the case of a solid elastomer, the particle size is preferably 0.2 mm or less.

[0027] When these elastomers having a crosslinked structure are mixed with a thermosetting resin having a dihydrobenzoxazine ring and cured, a sea-island type dispersion structure in which the selected particle size is maintained as long as the particles are not mixed easily can be easily obtained. And toughness is improved.

The functional groups of the thermosetting resin having a dihydrobenzoxazine ring and the liquid elastomer having a functional group capable of reacting with a phenolic hydroxyl group generated by opening of the dihydrobenzoxazine ring include amino groups, epoxy groups, Carboxyl groups and phenolic hydroxyl groups.

The mixing ratio of the above elastomer is preferably 1 to 100 parts by weight of the thermosetting resin composition.
To 50 parts by weight, more preferably 2 to 40 parts by weight.
When the amount is less than 1 part by weight, it is difficult to improve the toughness, and when the amount exceeds 50 parts by weight, the mechanical properties may be deteriorated.

Further, in the resin composition of the present invention, ordinary inorganic fillers, organic fillers, and reinforcing fibers can be used as fillers. For example, staple fiber, yarn, cotton cloth,
Glass cloth, glass mat, glass fiber, carbon fiber,
Quartz fiber, flame-retardant synthetic fiber, silica powder, calcium carbonate, magnesium hydroxide and the like. Pretreatment of these with a coupling agent is also effective in improving the affinity of the interface with the resin.

Regarding the mixing of these resins and curing agents,
There are no particular restrictions on the method or order. The use of a coupling agent at this time is also effective for improving the affinity of the interface with the resin.

If necessary, a release agent and a coloring agent can be used in combination.

The method for producing a copper-clad laminate, a prepreg, a sealing material, and a molding material from these resin compositions is not particularly limited.

Usually, these resin compositions are converted into a solution by using an organic solvent, and then applied to a substrate and dried. The thus-prepared prepregs are laminated, copper foils are formed on both sides thereof, and then pressed, whereby a copper-clad laminate can be manufactured. Further, by melting and kneading the resin composition and the filler, a sealing material, a molding material, and the like can be manufactured.

The thermosetting composition of the present invention does not generate volatile by-products at the time of curing, so that it has no odor or the like and does not cause deterioration of the working environment.

[0036]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be specifically described below with reference to embodiments.

As the resin having a dihydrobenzoxazine ring, two kinds of resins were synthesized by the following method.

(Resin A) (1) Synthesis of phenol novolak resin phenol 1.9 kg, formalin (37% aqueous solution) 1.0
kg and 4 g of oxalic acid were charged into a 5-liter flask and reacted at a reflux temperature for 6 hours. Then, 6666.1 Pa inside
Unreacted phenol and water were removed under reduced pressure to obtain a phenol novolak resin. The obtained phenol novolak resin has a softening point of 84 ° C. (ring and ball method),
The polynuclear / binuclear ratio (peak area ratio by gel permeation chromatography) was 82/18.

(2) Introduction of Dihydrobenzoxazine Ring 1.70 kg (corresponding to 16 mol of hydroxyl groups) of the phenol novolak resin obtained above was treated with 1.49 kg (16 m2) of aniline.
ol) and stirred at 80 ° C. for 5 hours to prepare a uniform mixed solution. 1.62 kg of formalin was charged into a 5 liter flask and heated to 90 ° C., and a mixed solution of phenol novolak resin / aniline was gradually added thereto over 30 minutes. At the end of the addition, the mixture was kept at the reflux temperature for 30 minutes and then reduced to 6666.1 Pa or less at 100 ° C. for 2 hours to remove the condensed water, and 75% of the reactive hydroxyl groups (by NMR analysis) were converted to dihydrobenzoxazine. A modified resin (A) was obtained.

(Resin B) Resin (B) having a dihydrobenzoxazine ring introduced therein was prepared in the same manner as in Resin A except that a mixture of 0.93 kg of aniline and 0.64 kg of toluidine was used instead of aniline. The obtained resin (B) was a phenol novolak resin in which a dihydrobenzoxazine ring was introduced into 71% (by NMR analysis) of a reactive hydroxyl group.

As a phenol novolak resin which is a curing agent for a resin having a dihydrobenzoxazine ring, HP-850N manufactured by Hitachi Chemical Co., Ltd. was used. Further, a proto-epoxy resin YDB-400T manufactured by Toto Kasei Kogyo Co., Ltd. was used as a flame retardant. As an elastomer, cross-linked NBR, XER- manufactured by Nippon Synthetic Rubber Co., Ltd.
91 was used.

Resins having a phenolic hydroxyl group and a primary amino group in the molecule are disclosed in JP-A-5-105734 and JP-A-5-105734.
The following two types were synthesized according to the method described in JP-A-7-18060.

(Resin C): hydroxyl equivalent (g / eq) 2
01, amine equivalent (g / eq) 820, average molecular weight 6
20 (Resin D): hydroxyl equivalent (g / eq) 115, amine equivalent (g / eq) 227, average molecular weight 650 As a comparative material, only a resin having a dihydrobenzoxazine ring was used.

[0044]

Examples 1 to 4 and

Comparative Examples 1 and 2 The resin compositions shown in Examples 1 to 4 and Comparative Examples 1 and 2 were measured for gel time, glass transition temperature after curing at 185 ° C. for 90 minutes, and water absorption.

Gel time: 0.3 g of the resin or composition was stirred on a pot plate maintained at 160 ° C. with a 1 mm-diameter iron bar at a rate of once / second, and the time until stringiness disappeared was measured.

Glass transition temperature: Thermomechanical measuring device (TM
It was determined from the inflection point of the thermal expansion curve (heating rate 10 ° C./min) according to A).

Water absorption: The cured product cured under the above conditions was left in a pressure cooker (PCT) pot at 121 ° C. for 20 hours, and then determined by the rate of change in weight after PCT with respect to the initial weight.

[0048]

[Table 1]

[0049]

[Table 2]

[0050]

Embodiments 5 and 6; and

Comparative Example 3 A metal foil-clad laminate was prepared by dissolving the resin compositions shown in Examples 1 and 2 and Comparative Example 1 in MEK and applying 55% varnish to a glass cloth to prepare a coated cloth and prepreg. did. The coating conditions are 140 ° C / 1.5 minutes + 170 ° C /
2 minutes + 175 ° C / 2 minutes + 150 ° C / 1.5 ° C minutes. A copper foil (18 μm) was arranged on both sides of the obtained eight coated cloths,
The temperature was raised from room temperature to 185 ° C. for 30 minutes under a pressure of 30 kgf / cm ² , and then heated and pressed at 185 ° C. for 15 minutes to obtain a copper-clad laminate. After the obtained copper-clad laminate was treated by a pressure cooker method for a predetermined time, it was immersed in a solder bath (260 ° C., 20 seconds) to measure the time until blistering occurred.

[0051]

[Table 3]

[0052]

Embodiments 7 and 8; and

Comparative Example 4 Carbana wax, carbon black, epoxy silane, and fused silica were separately mixed with 1,2,2,320 parts by weight of the resins shown in Examples 3 and 4 and Comparative Example 1, respectively. Was kneaded at 90 ° C. for 30 minutes using a hot roll to prepare a sealing material. Using the sealing material, a semiconductor element was transferred at 185 ° C. and 70 kgf / cm ² by a transfer molding machine.
Seal molding was performed under the condition of 180 seconds. Next, the sealed product was post-cured at 180 ° C. for 6 hours to obtain a target semiconductor device.

The reliability of the semiconductor device is 85 ° C., 85 ° C.
% RH for 24 hours.
Heat treatment was performed for 0 second (reflow crack test) to evaluate the rate of occurrence of package cracks.

[0054]

[Table 4]

[0055]

According to the present invention, it is possible to obtain a thermosetting resin composition which is excellent in curability and can provide a cured product having excellent heat resistance, moisture resistance and the like. In addition, highly reliable electronic components and electric appliances using the thermosetting resin composition can be obtained.

 ──────────────────────────────────────────────────の Continuing on the front page (72) Inventor Hideo Nagase 1500 Oji Ogawa, Shimodate City, Ibaraki Prefecture Inside the Shimodate Plant, Hitachi Chemical Co., Ltd. Inside the Shimodate Plant (72) Inventor Shinichi Kamoshida 1500 Oji Ogawa, Shimodate City, Ibaraki Prefecture Inside the Shimodate Plant, Hitachi Chemical Co., Ltd. 72) Inventor Shunichi Numata 48 Wadai, Tsukuba-shi, Ibaraki Prefecture F-term in Tsukuba Development Laboratory, Hitachi Chemical Co., Ltd. (reference) DG01H DH01A GB43 HB31 JB01 JB12 JB13A JJ03 4J002 CC07X CC28W GF00 GJ01 GQ05

Claims (6)

[Claims] 1. A compound of the general formula (1) A thermosetting resin composition comprising: a resin having a benzoxazine ring represented by the formula: and a phenol resin having a primary amino group. 2. A cured resin obtained by curing the thermosetting resin composition according to claim 1. 3. A composite molding material comprising the thermosetting resin composition according to claim 1 and at least one of an inorganic filler and a fiber material. 4. A prepreg obtained by impregnating a substrate with a varnish containing the thermosetting resin composition according to claim 1 and then drying. 5. A metal foil-clad laminate obtained by laminating the prepreg according to claim 4 and a metal foil. 6. A printed wiring board formed by bonding and molding the composite molding material according to claim 2 and a conductive pattern.