JP2013060545A - Phenolic resin composition - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a phenolic resin composition excellent in metal adhesivity and heat resistance of its cured material.SOLUTION: The phenolic resin composition contains a phenolic resin and a disulfide compound, and the disulfide compound contains a compound represented by formula (1) and a compound represented by formula (2). R-S-S-R...(1) wherein Rand Rare hydrogen, or a 1-16C aliphatic group or an aromatic group having a hydroxyl group, a mercapto group, a carboxyl group, an amino group or an amide group, and may be identical or different. In formula (2), n is an integer of 1 to 6; Rto Rare hydrogen, a hydroxyl group, a mercapto group, a carboxyl group, an amino group or an amide group, or a 1-16C aliphatic group or an aromatic group having these substituents, and may be identical or different.

Description

The present invention relates to a phenolic resin composition excellent in metal adhesion and heat resistance of a cured product.

Phenolic resin, a kind of thermosetting resin, has excellent mechanical properties, heat resistance, dimensional stability, chemical resistance, water resistance, and electrical / electronic parts that require electrical insulation and mechanical strength. It is used for packaging materials and industrial parts such as copper-clad laminates for printed wiring, as well as wood adhesives and paints.

Among phenolic resins, phenolic resins are generally synthesized by a reaction between phenols and aldehydes, and under a phenol-excess reaction condition, a thermoplastic resin intermediate called a novolac type is obtained. Under the conditions, a resin intermediate called a resol type is obtained. In addition to phenolic resins, benzoxazine resins that do not generate by-product gas during curing and have excellent moldability and heat resistance have been developed as phenolic resins.

On the other hand, phenolic resins have a problem of weak adhesive strength with difficult-to-adhere metals such as gold, silver, copper, and aluminum. In the field of electronic materials, semiconductor encapsulating materials can be cited as applications requiring adhesive strength with metals, and improvements in adhesion with lead frames (Cu, Au) and the like are desired. In the automotive parts field, there is a problem of low adhesion between the metal segment of the commutator part, which is the rotating part of the motor, and the resin. When the commutator rotates, the metal segment floats, creating a level difference, causing noise, etc. It is generated and the reliability is remarkably lowered, so that improvement in metal adhesion is desired.

Examples of methods for improving the metal adhesion of phenolic resins include a method in which the copper segment surface is boiled with caustic soda and a potassium persulfate aqueous solution to form a cupric oxide film (Patent Document 1), and an epoxy group-containing acrylic. A method of blending resin (Patent Document 2), a method of blending melamine (Patent Document 3), a method of blending silicon gel in addition to melamine (Patent Document 4), a method of blending melamine cyanurate (Patent Document 5) Etc. are disclosed.

JP 58-212943 A JP 2003-292723 A JP 2005-247946 A JP 2006-77061 A JP 2005-263945 A

An object of this invention is to provide the phenol-type resin composition excellent in metal adhesiveness and the heat resistance of hardened | cured material.

The present invention contains a phenolic resin and a disulfide compound, and the disulfide compound contains a compound represented by the following general formula (1) and / or a compound represented by the following general formula (2). It is a resin composition.

Wherein ^{(1), R 1, R} 2 represents hydrogen, a hydroxyl group, a mercapto group, a carboxyl group, an amino group, or an aliphatic group or an aromatic group having 1 to 16 carbon atoms and having an amide group, they They may be the same or different.

In formula (2), n represents an integer of 1 to 6. R ^{3 to} R ⁸ represent hydrogen, a hydroxyl group, a mercapto group, a carboxyl group, an amino group, an amide group, or an aliphatic group having 1 to 16 carbon atoms or an aromatic group having these substituents. They may be the same or different.
The present invention is described in detail below.

Of the conventional methods for improving the adhesion of a phenolic resin to a metal, the method disclosed in Patent Document 1 does not modify the phenolic resin itself, but the method disclosed in Patent Document 2 The effect of improving the metal adhesion of the phenolic resin is as small as about 1.5 times. Further, in the methods disclosed in Patent Document 3, Patent Document 4, and Patent Document 5, the metal adhesion is greatly improved, but there is a problem in mechanical strength and heat resistance. Therefore, it has been required to improve the adhesion to metals such as copper while maintaining the excellent heat resistance of the phenolic resin.
Therefore, the present inventors can greatly improve the metal adhesion of the phenolic resin composition and the heat resistance of the cured product by blending the phenolic resin composition with a disulfide compound having a specific structure. The present inventors have found that the present invention can be accomplished and have completed the present invention.

The reason why the metal adhesion of the phenolic resin composition and the heat resistance of the cured product are greatly improved by blending the phenolic resin composition with a disulfide compound having a specific structure is sulfur-sulfur of the disulfide compound. The effect of improving metal adhesion by the cleavage of the bond and the formation of a sulfur-metal interaction is combined with the effect of thermally stabilizing the reaction system due to the specific structure of the disulfide compound. It is thought that it is demonstrated.

The phenolic resin composition of the present invention contains a disulfide compound.
By containing the disulfide compound, the phenolic resin composition of the present invention is excellent in metal adhesion and heat resistance of the cured product. Moreover, the said disulfide compound also has a role as a catalyst which accelerates | stimulates hardening of a phenol-type resin.

The disulfide compound contains a compound represented by the general formula (1) and / or a compound represented by the general formula (2).

In order to greatly improve the adhesion to a metal, in the general formula (1), R ¹ and R ² are preferably other than hydrogen, and in the general formula (2), at least of R ^{3 to} R ⁸ One substituent is preferably other than hydrogen.

In the phenolic resin composition of the present invention, since the cured product of the obtained phenolic resin composition has excellent heat resistance, the compound represented by the general formula (1) is represented by the following general formula (3). It is preferable to contain the represented diphenyl disulfide compound.

In formula (3), R ⁹ and R ¹⁰ are hydrogen, a hydroxyl group, a mercapto group, a carboxyl group, an amino group, an amide group, or a C 1-10 aliphatic group or aromatic group having these substituents. These may be the same as or different from each other. Among these, in order to greatly improve the adhesion to metal, R ⁹ and R ¹⁰ are preferably other than hydrogen, more preferably a hydroxyl group or an amino group, and even more preferably an amino group. As the diphenyl disulfide compound represented by the general formula (3), 4,4′-dithiodianiline is more preferable.

The content of the disulfide compound is preferably 0.01 parts by weight and preferably 20 parts by weight with respect to 100 parts by weight of the phenolic resin. When the content of the disulfide compound is less than 0.01 parts by weight, the obtained phenolic resin composition may be inferior in metal adhesion. When content of the said disulfide compound exceeds 20 weight part, the hardened | cured material of the obtained phenol-type resin composition may become inferior to heat resistance or mechanical strength. The minimum with more preferable content of the said disulfide compound is 0.1 weight part, and a more preferable upper limit is 10 weight part.

The phenolic resin composition of the present invention contains a phenolic resin.
In the present specification, the above “phenolic resin” means a resin having a phenol structure in a repeating unit in a cured product.
Examples of the phenolic resin include benzoxazine resins, phenolic resins such as novolac type phenolic resins and resol type phenolic resins, and the like. Among these, a benzoxazine resin is preferable because no by-product gas is generated when the resulting phenol-based resin composition is cured.

The benzoxazine resin means a compound having a benzoxazine ring.
Examples of the benzoxazine resin include resins represented by the following general formula (4-1) or (4-2), the following general formulas (5-1), (5-2), (5-3), Alternatively, a resin represented by (5-4), a resin represented by the following general formula (6), a resin obtained by ring-opening polymerization of benzoxazine, and the like can be given. Especially, resin represented by general formula (4-1) or (4-2) is preferable, and resin represented by general formula (4-1) is more preferable.

In formulas (4-1) and (4-2), n represents an integer of 1 to 4, and Y ¹ represents hydrogen, an alkyl group having 1 to 8 carbon atoms, a cycloalkyl group, an aryl group, an allyl group, or Represents an aralkyl group, and Y ² represents an alkyl group having 1 to 8 carbon atoms, a cycloalkyl group, an aryl group, an allyl group, or an aralkyl group.

In formulas (5-1) to (5-4), X ¹ represents CH ₂ , C (CH ₃ ) ₂ , O, S, or SO ₂ .

In formula (6), n represents an integer and is not particularly limited, but is preferably 1 to 20, and X ² is hydrogen, an alkyl group having 1 to 8 carbon atoms, an alkoxy group having 1 to 4 carbon atoms, It represents at least one functional group selected from the group consisting of a methylol group and a phenyl group, and X ³ represents the following formula (7-1), (7-2), (7-3) or (7- The substituent represented by 4) is represented.

Moreover, as said phenol resin, resin etc. which are represented by following General formula (8) are mentioned, for example.

In formula (8), n represents an integer and is not particularly limited, but is preferably 1 to 20, and X ⁴ is hydrogen, an alkyl group having 1 to 8 carbon atoms, an alkoxy group having 1 to 4 carbon atoms, It represents at least one functional group selected from the group consisting of a methylol group and a phenyl group, and X ⁵ and X ⁶ represent an alkyl group having 1 to 10 carbon atoms.

The phenolic resin composition of the present invention may contain other resins other than the phenolic resin, if necessary.
Examples of the other resin include epoxy resin, urea resin, melamine resin, unsaturated polyester, vinyl ester resin, diallyl phthalate resin, polyurethane, silicon resin, polyimide, vinyl chloride resin, vinylidene chloride resin, vinyl acetate resin, polystyrene. Methacrylic resin, polyethylene, polypropylene, fluororesin, polyamide, polyacetal, polycarbonate, polyester, polyphenylene ether, polyphenylene sulfide, polyarylate, polysulfone, polyethersulfone, polyetheretherketone, liquid crystalline polymer and the like.

When a novolac type phenol resin or a resol type phenol resin is used as the phenolic resin, the phenolic resin composition of the present invention preferably contains a curing agent.
As the curing agent in the case of using the novolac type phenol resin, hexamitylenetetramine is generally used and can also be used in the phenolic resin composition of the present invention. Moreover, as a hardening | curing agent in the case of using the said resol type phenol resin, sodium hydroxide, sodium carbonate, the hydroxide of alkaline-earth metal, ammonia, a tertiary amine, etc. are mentioned.
Examples of other curing agents include amine-based curing agents, acid anhydride-based curing agents, polyamide-based curing agents, and latent curing agents such as boron trifluoride amine complex and dicyandiamide. can do.
Examples of the amine curing agent include aliphatic polyamines such as diethylenetriamine and triethylenetetramine, and aromatic polyamines such as metaphenylenediamine, diaminodiphenylmethane, and diaminodiphenylsulfone. However, although the amine-based curing agent exhibits excellent adhesion to metals, it causes toxicity to the human body, high viscosity, and coloring.
Examples of the acid anhydride-based curing agent include succinic anhydride, maleic anhydride, phthalic anhydride, hexahydrophthalic anhydride, methylhexahydrophthalic anhydride, methyltetrahydrophthalic anhydride, nadic anhydride, and hydrogenated anhydride. Nadic acid, trimetic anhydride, pyromellitic anhydride, etc. can be used.
The above acid anhydride curing agent is easy to handle with low viscosity, the pot life is relatively long, the cured product is excellent in electrical insulation, mechanical properties, heat stability, chemical resistance, It has advantages such as superior safety and hygiene compared to the amine curing agent, and is suitable for optical semiconductor sealing materials such as LED elements, semiconductor sealing materials, and electrical / electronic insulating materials. Can be used. Among these acid anhydride curing agents, phthalic anhydride, hexahydrophthalic anhydride, and methylhexahydrophthalic anhydride are preferably used.
These curing agents may be used alone or in combination of two or more.

In general, a curing agent such as an acid anhydride curing agent has a long pot life and low toxicity, but on the other hand, the curing reaction proceeds relatively slowly, and thus curing may require a high temperature and a long time. Therefore, you may use a hardening | curing agent and a hardening accelerator together as needed.

Examples of the curing accelerator include tertiary amines such as benzylmethylamine and imidazoles such as 2-ethyl-4-methylimidazole.
When a phenol resin suitable for a semiconductor sealing material is used as the curing agent, imidazoles such as 2-methylimidazole, 2-ethylimidazole, 2-ethyl-4-methylimidazole, 2- Use tertiary amines such as (dimethylaminomethyl) phenol and 1,8-diazabicyclo (5.4.0) -undecene-7, phosphines such as triphenylphosphine, and metal compounds such as tin octylate. Is preferred.

The phenolic resin composition of the present invention may contain an inorganic filler.
Examples of the inorganic filler include glass fiber, fused silica, crystalline silica, alumina, aluminum hydroxide, clay, talc, and kaolin.

The phenolic resin composition of the present invention may contain a release agent.
Examples of the release agent include stearic acid, zinc stearate, montanic acid, and polyolefin.

The phenolic resin composition of the present invention may contain a silane coupling agent.
Examples of the silane coupling agent include amino silane, epoxy silane, mercapto silane, and the like.

The phenolic resin composition of the present invention may contain a colorant.
Examples of the colorant include inorganic pigments and organic pigments such as carbon black.

The method for producing the phenolic resin composition of the present invention is not particularly limited, and the above-mentioned phenolic resin, the above disulfide compound, and additives such as other resins and curing agents to be added as necessary are three rolls. The method of mixing using etc. is mentioned.

Although the temperature at the time of mixing the said phenol-type resin and the said disulfide compound is not specifically limited, The preferable minimum of the temperature to mix is 50 degreeC, and a preferable upper limit is 250 degreeC. When the temperature at the time of mixing the phenolic resin and the disulfide compound is less than 50 ° C., the disulfide compound is not uniformly dispersed, and the cured product of the resulting phenolic resin composition has high heat resistance and mechanical strength. May be inferior. When the temperature at the time of mixing the phenolic resin and the disulfide compound exceeds 250 ° C., the disulfide compound is decomposed, and the cured product of the resulting phenolic resin composition may be inferior in heat resistance. The more preferable lower limit of the temperature when mixing the phenolic resin and the disulfide compound is 100 ° C., and the more preferable upper limit is 200 ° C.

Since the phenolic resin composition of the present invention is excellent in metal adhesion and heat resistance of a cured product, it is suitably used for semiconductor encapsulating materials, commutator parts that are rotating parts of motors, and the like. In addition, it can be used for applications such as paints, coating agents, printing inks, resist inks, adhesives, molding materials, and electrical insulating materials.

ADVANTAGE OF THE INVENTION According to this invention, the phenol resin composition excellent in metal adhesiveness and the heat resistance of hardened | cured material can be provided.

Hereinafter, the present invention will be described in more detail with reference to examples. However, the present invention is not limited to these examples.

Example 1
As phenolic resin, 4,4′-dithiodianiline (manufactured by Sumitomo Seika Co., Ltd., “DTDA”) as a disulfide compound with respect to 100 parts by weight of benzoxazine resin (manufactured by Shikoku Chemicals, “Fa type”) 0.1 part by weight was added and mixed while heating to 140 ° C. to obtain a phenolic resin composition.

(Example 2)
A phenolic resin composition was obtained in the same manner as in Example 1 except that the amount of 4,4′-dithiodianiline was changed to 1 part by weight.

(Example 3)
A phenolic resin composition was obtained in the same manner as in Example 1 except that the amount of 4,4′-dithiodianiline was changed to 2 parts by weight.

Example 4
A phenolic resin composition was obtained in the same manner as in Example 1 except that 2 parts by weight of 3,3′-dihydroxydiphenyl disulfide (manufactured by Tokyo Chemical Industry Co., Ltd.) was blended in place of 4,4′-dithiodianiline. It was.

(Example 5)
A phenolic resin composition was obtained in the same manner as in Example 1 except that 2 parts by weight of 1,2-dithiane was blended in place of 4,4′-dithiodianiline.

(Example 6)
Instead of 4,4′-dithiodianiline, a phenolic resin was used in the same manner as in Example 1 except that 2 parts by weight of trans-4,5-dihydroxy-1,2-dithiane (manufactured by Aldrich) was blended. A composition was obtained.

(Comparative Example 1)
No 4,4′-dithiodianiline was used and only benzoxazine resin was used.

(Comparative Example 2)
Example 1 except that 2 parts by weight of 4,4′-thiodiphenol (manufactured by Sumitomo Seika Co., Ltd., “TDP”), which is a monosulfide compound, was blended in place of 4,4′-dithiodianiline. Similarly, a phenolic resin composition was obtained.

(Comparative Example 3)
A phenolic resin composition was obtained in the same manner as in Example 1 except that 2 parts by weight of a melamine monomer (manufactured by Tokyo Chemical Industry Co., Ltd.) as a triazine compound was blended in place of 4,4′-dithiodianiline.

(Comparative Example 4)
Ricacid MH-700 (manufactured by Nippon Nippon Chemical Co., Ltd., 4-methylhexahydrophthalic anhydride / hexahydrophthalic anhydride = 100 parts by weight of bisphenol A type epoxy resin (manufactured by Mitsubishi Chemical Corporation, “jER828”) = 70/30) 90 parts by weight, 1 part by weight of 2-ethyl-4-methylimidazole (manufactured by Shikoku Kasei Co., Ltd., “Cureazole 2E4MZ”) was added as a curing accelerator to obtain an epoxy resin composition.

(Comparative Example 5)
A curing agent is prepared by dissolving 2 parts by weight of 4,4′-dithiodianiline (“DTDA”, manufactured by Sumitomo Seika Co., Ltd.) with respect to 100 parts by weight of a bisphenol A type epoxy resin (manufactured by Mitsubishi Chemical, “jER828”). 90 parts by weight of Ricacid MH-700 (manufactured by Shin Nippon Rika Co., Ltd., 4-methylhexahydrophthalic anhydride / hexahydrophthalic anhydride = 70/30), and 2-ethyl-4-methylimidazole (Shikoku Kasei Co., Ltd.) as a curing accelerator 1 part by weight of “Cureazole 2E4MZ” was added to obtain an epoxy resin composition.

<Evaluation>
The following evaluation was performed on the epoxy resin compositions obtained in Examples 1 to 6 and Comparative Examples 2 and 3, the benzoxazine resin of Comparative Example 1 and Comparative Examples 4 and 5. It was. The results are shown in Tables 1-3.

(90 degree peel adhesion strength test)
An electrolytic copper foil (manufactured by Fukuda Metal Powder Co., Ltd.) having a nominal thickness of 35 μm and a smooth surface roughness Rz = 0.25 μm was cut into a size of 5 cm to 5 cm and washed with acetone to wash the preservative. Etching with% nitric acid for 30 seconds, washing with distilled water, and drying at 60 ° C. gave a test piece.
The phenol resin composition, the benzoxazine resin, and the epoxy resin composition obtained in the examples and comparative examples were each applied to an aluminum plate, and the smooth surfaces of the test pieces obtained thereon were overlaid. After heating at 150 ° C. for 3 hours, the coating was further cured by heating at 180 ° C. for 3 hours. After curing, a 1 cm width was cut with a cutter to obtain a 90 ° peel test piece. The aluminum plate was degreased with acetone, then polished with abrasive paper (No. 600), the polishing debris removed with acetone and dried.
About the obtained 90 degree | times peeling test piece, the 90 degree | times peeling adhesive strength test was implemented on the conditions of the test speed of 25 mm / min using DAGE-SERISE4000 (made by an arc rack company).

(5% weight loss temperature)
The phenolic resin composition, benzoxazine resin, and epoxy resin composition obtained in Examples and Comparative Examples were cured by heating at 150 ° C. for 3 hours and 180 ° C. for 3 hours, respectively, and the cured product was finely pulverized and measured. It was.
About the obtained test piece, 5% weight by temperature increase conditions 35-530 degreeC and 10 degrees C / min using the differential thermothermal weight simultaneous measuring apparatus (the SII nanotechnology company make, "TG / DTA6200"). The decrease temperature was measured.

(Exothermic temperature)
For the phenolic resin compositions obtained in Examples 3 and 4 and Comparative Example 3 and the benzoxazine resin of Comparative Example 1, using a differential scanning calorimeter (“DSC 6220” manufactured by SII Nanotechnology Inc.) The exothermic temperature at the time of hardening was measured on temperature rising conditions of 35-320 degreeC and 10 degrees C / min.
In addition, it shows that the one where the heat generation start temperature and the heat generation peak temperature of the first heat generation temperature and the second heat generation temperature shown in Table 3 are lower is cured at a lower temperature.

From Table 1, when the disulfide compound represented by the general formula (1) or the disulfide compound represented by the general formula (2) is added to the phenolic resin, Comparative Example 1 in which these disulfide compounds are not added and In comparison, the effect of improving the peel strength and heat resistance against copper was observed. In Example 3, the peel strength was improved about 5 times by adding 2 parts by weight of 4,4′-dithiodianiline to 100 parts by weight of the benzoxazine resin.
On the other hand, from Table 2, when a compound having no disulfide bond was added to the phenolic resin (Comparative Example 2), the effect of improving metal adhesion was not observed, and when a triazine compound was added (Comparative Example) In 3), although the metal adhesion was improved, the cured product of the obtained phenolic resin composition was inferior in heat resistance.
Moreover, it turns out that the disulfide compound represented by the said General formula (1) does not show the outstanding effect with respect to an epoxy resin from the result of Comparative Examples 4 and 5. In addition, a decrease in heat resistance was observed when the disulfide compound was added.
Moreover, from Table 3, when only the benzoxazine resin was used (Comparative Example 1), the addition of the disulfide compound represented by the general formula (1) resulted in a lower curing temperature (Examples). 3, 4). When the triazine compound was added (Comparative Example 3), the curing temperature was low, but the effect was less than that of the Example.

ADVANTAGE OF THE INVENTION According to this invention, the phenol resin composition excellent in metal adhesiveness and the heat resistance of hardened | cured material can be provided.

Claims (5)

Containing a phenolic resin and a disulfide compound,
The disulfide compound contains a compound represented by the following general formula (1) and / or a compound represented by the following general formula (2).

Wherein ^{(1), R 1, R} 2 represents hydrogen, a hydroxyl group, a mercapto group, a carboxyl group, an amino group, or an aliphatic group or an aromatic group having 1 to 16 carbon atoms and having an amide group, they They may be the same or different.

In formula (2), n represents an integer of 1 to 6. R ^{3 to} R ⁸ represent hydrogen, a hydroxyl group, a mercapto group, a carboxyl group, an amino group, an amide group, or an aliphatic group having 1 to 16 carbon atoms or an aromatic group having these substituents. They may be the same or different. The phenolic resin composition according to claim 1, comprising a diphenyl disulfide compound represented by the following general formula (3).

In formula (3), R ⁹ and R ¹⁰ are hydrogen, a hydroxyl group, a mercapto group, a carboxyl group, an amino group, an amide group, or a C 1-10 aliphatic group or aromatic group having these substituents. These may be the same as or different from each other. The phenolic resin composition according to claim 2, wherein the diphenyl disulfide compound represented by the general formula (3) is 4,4'-dithiodianiline. The phenolic resin composition according to claim 1, 2 or 3, wherein the content of the disulfide compound is 0.01 to 20 parts by weight with respect to 100 parts by weight of the phenolic resin. The phenolic resin composition according to claim 1, 2, 3, or 4, wherein the phenolic resin contains a benzoxazine resin.