JP2009242480A - Phenolic polymer, its production method, and its application - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a phenolic polymer suitable for sealing a semiconductor having low melting viscosity and flame retardancy, to provide its composition and to provide its production method. <P>SOLUTION: Phenols represented by formula (1), an aromatic compound represented by formula (2) (R<SP>1</SP>denotes hydrogen, a 1-6C alkyl or an aryl and X demotes a halogen, OH or OCH<SB>3</SB>), a m-xylene-formaldehyde condensate and formaldehyde are reacted at a molar ratio of the aromatic compound to the phenols of 0.1 to 0.6, at a rate by weight of the condensate to the phenols of 5 to 25% and at a molar ratio of formaldehyde to the phenols of 0.01 to 0.20 to obtain the phenolic polymer. In the easy and inexpensive production method of the phenolic polymer, the phenols, the aromatic compound and the condensate are reacted and then formaldehyde is added to condense them. As the composition, an epoxy resin composition with an epoxy resin is suitable. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a phenolic polymer, a process for producing the same, and a use thereof. More specifically, the present invention relates to a phenolic polymer suitable for semiconductor sealing applications having a low melt viscosity and flame retardancy, a composition thereof, and a method for producing the same.

  When phenol aralkyl resin is used as a curing agent for epoxy resin, it has excellent physical properties such as heat resistance, moisture resistance, mechanical properties, etc., and a low-viscosity resin can be produced. Used for molds and surface mounting resins, especially as semiconductor sealing resins.

  In recent years, as semiconductor packages have become smaller and thinner and more complicated in shape, semiconductor sealing resins are increasingly required to have low viscosity. If the viscosity is low, the filler can be filled with a high amount, which is advantageous not only in terms of solder heat resistance and moisture resistance reliability, but also improved in fluidity and can be applied to a package having a complicated shape such as BGA.

  In recent years, there has been a movement to reduce or eliminate substances that may be harmful due to the importance of corporate activities in consideration of the global environment. Epoxy resins have excellent flame resistance without using halogenated flame retardants and antimony compounds. There is a need for an epoxy resin composition that is excellent in flame retardancy without using a halogen-based flame retardant and antimony compound, even in phenolic aralkyl resins that have been used for advanced packages, and in general-purpose packages. Since it is used, it is used (patent documents 1, 2). At present, there is a demand for a curing agent having flame retardancy equal to or higher than that of phenol aralkyl resin and having a low melt viscosity.

Japanese Patent Application No. 5-97965 Japanese Patent Application No. 11-5831

  An object of the present invention is to provide a phenolic polymer suitable for semiconductor sealing applications having a low melt viscosity and flame retardancy, a composition thereof, and a production method thereof.

  The present invention relates to a phenol represented by the following general formula (1), an aromatic compound represented by the following general formula (2), an m-xylene / formaldehyde condensate, and formaldehyde with respect to the phenolic aromatic compound. The molar ratio is 0.1 to 0.6, the m-xylene / formaldehyde condensate is 5 to 25% by weight based on phenols, and the molar ratio of formaldehyde to phenols is 0.01 to 0.20. A phenolic polymer obtained by reacting under conditions is provided.

（式（１）中、Ｒ^１は水素、炭素数１〜６のアルキル基またはアリール基であり、式（２）中、Ｘはハロゲン、ＯＨ基又はＯＣＨ_３基である。）
。

(In formula (1), R ¹ is hydrogen, an alkyl group having 1 to 6 carbon atoms or an aryl group, and in formula (2), X is a halogen, OH group or OCH ₃ group.)
.

  The present invention provides an epoxy resin composition comprising the above-described phenolic polymer and an epoxy resin.

  The present invention also provides a condensate of the phenol represented by the general formula (1), the aromatic compound represented by the general formula (2), and the m-xylene / formaldehyde resin with respect to the phenol of the aromatic compound. After reacting under the condition that the molar ratio is 0.1 to 0.6 and the m-xylene / formaldehyde condensate is 5 to 25% by weight based on the phenols, the molar ratio of formaldehyde to the phenols is further 0.1. A method for producing a phenolic polymer obtained by adding and condensing at 01 to 0.20 is provided.

  ADVANTAGE OF THE INVENTION According to this invention, the phenolic polymer which is useful for a molding material, various binders, a coating material, a laminated material, etc., and is low melt viscosity but high in softening point and its manufacturing method are provided.

  According to the present invention, a phenolic polymer that is particularly useful as an epoxy resin curing agent and can form an epoxy resin composition excellent in low melt viscosity and flame retardancy, especially when used for semiconductor encapsulation, And an epoxy resin composition thereof.

  The present invention provides a phenol represented by the general formula (1), an aromatic compound represented by the general formula (2), an m-xylene / formaldehyde condensate, and formaldehyde. The molar ratio with respect to phenol is 0.1 to 0.6, the m-xylene / formaldehyde condensate is 5 to 25% by weight based on the phenols, and the molar ratio of formaldehyde to phenols is 0.01 to 0.20. Provided is a phenolic polymer obtained by reacting under certain conditions.

A phenolic polymer represented by the formula:

  The present invention also provides a condensate of the phenol represented by the general formula (1), the aromatic compound represented by the general formula (2), and the m-xylene / formaldehyde resin with respect to the phenol of the aromatic compound. After reacting under the condition that the molar ratio is 0.1 to 0.6 and the m-xylene / formaldehyde condensate is 5 to 25% by weight based on the phenols, the molar ratio of formaldehyde to the phenols is further 0.1. A method for producing a phenolic polymer obtained by adding and condensing at 01 to 0.20 is provided.

  Examples of the phenols represented by the general formula (1) include phenol, (o-, m-, p-) cresol, xylenol, (o-, p-) ethylphenol, butylphenol, halogenated phenol, catechol, resorcin and the like. Monocyclic phenol compounds, or polycyclic phenol compounds such as biphenol, bisphenol A, bisphenol S, bisphenol F, α-naphthol, and β-naphthol, and one or more of these can be used. Is particularly preferred phenol.

  The condensate of m-xylene / formaldehyde is commercially available (for example, “Nikanol” (trade name) manufactured by Fudou Co., Ltd.), and can be easily obtained from commercial products.

  Examples of the aromatic compound represented by the general formula (2) include 1,2-di (chloromethyl) benzene, 1,2-di (bromomethyl) benzene, 1,3-di (chloromethyl) benzene, 1,3 -Di (fluoromethyl) benzene, 1,4-di (chloromethyl) benzene, 1,4-di (bromomethyl) benzene, 1,4-di (fluoromethyl) benzene and the like can be mentioned. Of these aromatic bishalogenomethyl compounds, 1,4-di (chloromethyl) benzene is most commonly available as a raw material and is common.

  Said

After the phenolic polymer represented by the general formula (1), the aromatic compound represented by the general formula (2), and the m-xylene / formaldehyde condensate are reacted, It can be obtained by condensing formaldehyde.

  In the reaction of the above (1), (2) and m-xylene / formaldehyde condensate, in order to obtain a phenolic polymer having an appropriate molecular weight and excellent performance as a curing agent for epoxy resins, aroma to phenols The molar ratio of the group compound is 0.01 to 0.60, preferably 0.15 to 0.48, and 5 to 25% by weight of m-xylene / formaldehyde condensate with respect to the weight of phenol is preferably 10 to 20 After the reaction in weight%, formaldehyde is further reacted at a ratio of formaldehyde / phenols (molar ratio) of 0.01 to 0.20, preferably 0.05 to 0.15.

The above reaction can be obtained by reacting at a temperature of about 60 to 150 ° C. for about 1 to 10 hours in the presence or absence of a catalyst. That is, in the formula (2), when X is an OH group or OCH ₃ group, it is necessary to carry out the reaction in the presence of an acid catalyst, and when X is a halogen in the formula (2), a slight amount is required. The reaction can be initiated by the presence of water and can proceed with the hydrogen halide produced by the reaction.

  Acid catalysts that can be used in the above reaction include inorganic acids such as phosphoric acid, sulfuric acid, and hydrochloric acid, organic acids such as oxalic acid, benzenesulfonic acid, toluenesulfonic acid, methanesulfonic acid, and fluoromethanesulfonic acid, zinc chloride, and chloride chloride. Friedel-Crafts catalysts such as 2 tin, ferric chloride and diethyl sulfate can be used alone or in combination.

  When the product phenolic polymer is used for electronic material applications such as semiconductor encapsulation, it is not preferable that the acid remains. Therefore, by using hydrochloric acid as the acid catalyst, the condensation reaction mixture is chlorinated under reduced pressure. Hydrogen is preferred because it can be easily removed.

  By removing unreacted raw materials (for example, phenols), reaction by-products (for example, hydrogen halide and methanol), catalysts (for example, hydrochloric acid) and the like from the condensation reaction mixture obtained by the above condensation reaction under reduced pressure, a reaction product is obtained. It is possible to separate the phenolic polymer. Such a reaction product has an ICI melt viscosity at 150 ° C. of 10 to 200 mPa · s, preferably 50 to 180 mPa · s. The separation operation under reduced pressure performed for removing unreacted raw materials and the like in the reaction product is usually performed at a temperature of 130 ° C. or higher, so that the molten reaction product obtained by the operation is used as it is. By quenching and solidifying, it can be isolated as an amorphous solid having a softening point (JIS K2207) of about 50 to 80 ° C.

  The phenolic polymer, which is the reaction product thus obtained, is generally excellent in transparency, has a low melt viscosity in the molding temperature range, and is excellent in workability. Therefore, it can be used for molding materials, various binders, coating materials, laminated materials and the like. Especially useful as an epoxy resin curing agent, and when used as a curing agent in an epoxy resin-based semiconductor encapsulant, the epoxy cures quickly and has low moisture absorption, low thermal modulus, high adhesion, and excellent flame retardancy. A resin composition can be obtained.

  Examples of the epoxy resin that can be used with the phenolic polymer in the epoxy resin composition include bisphenol A type epoxy resin, bisphenol F type epoxy resin, cresol novolac type epoxy resin, phenol novolac type epoxy resin, and biphenyl type. Epoxy resins, phenol biphenyl aralkyl type epoxy resins, epoxidized aralkyl resins with xylylene bonds such as phenol and naphthol, glycidyl ether type epoxy resins such as dicyclopentadiene type epoxy resin, dihydroxynaphthalene type epoxy resin, triphenolmethane type epoxy resin And epoxy resins having two or more epoxy groups in the molecule such as glycidyl ester type epoxy resin and glycidyl amine type epoxy resin It is. These epoxy resins may be used alone or in combination of two or more. Considering moisture resistance, low elastic modulus during heat, flame retardancy, etc., bifunctional epoxy resins such as bisphenol F type epoxy resin and biphenyl type epoxy resin, and xylylene bonds such as phenol biphenyl aralkyl type epoxy resin, phenol and naphthol It is preferable to use a polyfunctional epoxy resin having many aromatic rings selected from epoxidized aralkyl resins.

  In curing the epoxy resin, it is desirable to use a curing accelerator in combination. As such a curing accelerator, a known curing accelerator for curing an epoxy resin with a phenol resin curing agent can be used. For example, a tertiary amine, a quaternary ammonium salt, an imidazole and a tetraphenylboron salt thereof, An organic phosphine compound and its boron salt, a quaternary phosphonium salt, etc. can be mentioned. More specifically, tertiary amines such as triethylamine, triethylenediamine, benzyldimethylamine, 2,4,6-tris (dimethylaminomethyl) phenol, 1,8-diazabicyclo (5,4,0) undecene-7, -Imidazoles such as methylimidazole, 2,4-dimethylimidazole, 2-ethyl-4-methylimidazole, 2-phenylimidazole, 2-phenyl-4-methylimidazole, triphenylphosphine, tributylphosphine, tri (p-methyl) Examples thereof include organic phosphine compounds such as phenyl) phosphine and tri (nonylphenyl) phosphine, tetraphenylphosphonium tetraphenylborate, tetraphenylphosphoniumtetranaphthoic acid borate and the like. Of these, organic phosphine compounds and quaternary phosphonium quaternary borate salts are preferred from the viewpoint of low water absorption and reliability.

  In the epoxy resin composition of the present invention, an inorganic filler, a coupling agent, a release agent, a colorant, a flame retardant, a flame retardant aid, a low stress agent, or the like is added or reacted in advance as necessary. Can be used. Other curing agents can be used in combination. Examples of such other curing agents include phenol novolac resins, phenol aralkyl resins, phenol biphenyl aralkyl resins, phenol naphthyl aralkyl resins, naphthol aralkyl resins, and triphenolmethane type novolac resins.

  When using the said epoxy resin composition for semiconductor sealing, addition of an inorganic filler is essential. Examples of such inorganic fillers include amorphous silica, crystalline silica, alumina, glass, calcium silicate, gypsum, calcium carbonate, magnesite, clay, talc, mica, magnesia, barium sulfate and the like. However, amorphous silica, crystalline silica and the like are particularly preferable. In order to increase the blending amount of the filler while maintaining excellent moldability, it is preferable to use a spherical filler having a wide particle size distribution that enables fine packing.

  Examples of coupling agents include silane coupling agents such as mercaptosilane, vinyl silane, aminosilane, and epoxy silane, and titanium coupling agents. Examples of mold release agents include carnauba wax, paraffin wax, stearin. Examples of the acid, montanic acid, carboxyl group-containing polyolefin wax, and the colorant include carbon black. Examples of the flame retardant include halogenated epoxy resins, halogen compounds, and phosphorus compounds, and examples of the flame retardant aid include antimony trioxide. Examples of the stress reducing agent include silicon rubber, modified nitrile rubber, modified butadiene rubber, and modified silicone oil.

  The mixing ratio of the phenolic polymer and the epoxy resin of the present invention is such that the equivalent ratio of hydroxyl group / epoxy group is 0.5 to 1.5, particularly 0.8 to 1.2, considering heat resistance, mechanical properties and the like. It is preferable that it exists in the range. Even when used in combination with other curing agents, the equivalent ratio of hydroxyl group / epoxy group is preferably adjusted to the above ratio. The curing accelerator is preferably used in the range of 0.1 to 5 parts by weight with respect to 100 parts by weight of the epoxy resin in consideration of curing characteristics and various physical properties. Furthermore, in the epoxy resin composition for semiconductor encapsulation, although slightly different depending on the type of inorganic filler, considering solder heat resistance, moldability (melt viscosity, fluidity), low stress, low water absorption, etc. It is preferable to blend the inorganic filler in a proportion that occupies 60 to 93% by weight of the entire composition.

  As a general method when preparing an epoxy resin composition as a molding material, a predetermined proportion of each raw material is sufficiently mixed by, for example, a mixer, then kneaded by a hot roll or a kneader, and further cooled and solidified, Examples thereof include a method of pulverizing to an appropriate size and tableting if necessary. The molding material thus obtained can be used for sealing a semiconductor by, for example, low-pressure transfer molding to manufacture a semiconductor device. Curing of the epoxy resin composition can be performed, for example, in a temperature range of 100 to 250 ° C.

  The present invention will be described more specifically with reference to examples and comparative examples below, but the present invention is not limited to these examples.

[Example 1]
Four-necked flask with 153.5 g (1.633 mol) of phenol, 60 g (0.342 mol) of 1,4-di (chloromethyl) benzene and 19.7 g of nicanol (Y-50) at the bottom When the temperature was raised, the system became a slurry at 50 ° C., dissolved uniformly at 70 ° C., and generation of HCl started. After maintaining at 70 ° C. for 1 hour, 19.9 g of 37% formalin ( 0.245 mol) was added, and after the addition was completed, the temperature was raised and maintained at 95 ° C. for 2 hours. HCl generated in the reaction was volatilized out of the system as it was and trapped with alkaline water. At this stage, unreacted 1,4-di (chloromethyl) benzene did not remain, and it was confirmed by gas chromatography that all had reacted. After completion of the reaction, the pressure was reduced to remove HCl remaining in the system and unreacted phenol out of the system. Finally, the residual phenol was not detected by gas chromatography by reducing the pressure to 150 ° C. at 30 torr. This reaction product was withdrawn while being kept at 150 ° C. to obtain 143.7 g of a pale yellowish brown yellow and transparent phenolic polymer (I).
The softening point of this phenolic polymer based on JIS K 2207 was 68 ° C. The melt viscosity at 150 ° C. measured with an ICI melt viscometer was 70 mPa · s. Furthermore, the hydroxyl group equivalent measured by the acetylation back titration method was 151 g / eq.

[Example 2]
The amount of phenol charged was 134.3 g (1.429 mol), the amount of 1,4-di (chloromethyl) benzene charged was 70.0 g (0.400 mol), and the amount of nicanol (Y-101) charged was 27. 0.6 g and the same procedure as in Example 1 except that 37% formalin was not added to obtain 137.0 g of a pale yellowish brown yellow transparent phenolic polymer (II).

  The softening point of this phenolic polymer (II) based on JIS K 2207 was 68 ° C. The melt viscosity at 150 ° C. measured with an ICI melt viscometer was 70 mPa · s. Furthermore, the hydroxyl group equivalent measured by the acetylation back titration method was 166 g / eq.

[Example 3]
The amount of phenol charged was 142.5 g (1.516 mol), the amount of 1,4-di (chloromethyl) benzene charged was 65.0 g (0.3714 mol), and the amount of nicanol (Y-101) charged was 25. Except that the amount was 1.6 g and 37% formalin was changed to 6.1 g (0.076 mol), the same procedure as in Example 1 was performed to obtain 139.7 g of a pale yellowish brown yellow transparent phenolic polymer (III). .

  The softening point of this phenolic polymer (III) based on JIS K 2207 was 67 ° C. The melt viscosity at 150 ° C. measured with an ICI melt viscometer was 60 mPa · s. Furthermore, the hydroxyl equivalent measured by the acetylated back titration method was 159 g / eq.

  The physical properties of the phenolic polymers (I) to (III) obtained in Examples 1 to 3 are shown in Table 1 in comparison with the phenol aralkyl resin used in Comparative Example 1 described later.

[Example 4]
Epoxy resin A represented by the following general formula (3) (biphenyl aralkyl type, epoxy equivalent 272 g / eq, NC-3000P manufactured by Nippon Kayaku Co., Ltd.), phenolic polymer (I) obtained in Example 1, molten Silica and a phosphorus curing accelerator (2- (triphenylphosphonio) phenolate) were blended in the proportions shown in Table 2, mixed thoroughly, then kneaded for 3 minutes with two rolls at 85 ° C. ± 3 ° C. and cooled. By crushing, a molding composition was obtained. This molding composition was molded with a transfer molding machine at a pressure of 100 kgf / cm ² at 175 ° C. for 2 minutes, and then post-cured at 180 ° C. for 6 hours for glass transition temperature (Tg) and flame resistance test. I got a test piece.

（式中、Ｇはグリシジル基、ｎは１〜１０の数）

(In the formula, G is a glycidyl group, n is a number of 1 to 10)

The physical properties of these molding materials were measured by the following method.
(1) Glass transition temperature (Tg)
The linear expansion coefficient was measured by TMA at a temperature rising rate of 5 ° C./min, and the inflection point of the linear expansion coefficient was defined as Tg.
(2) Flame retardancy Using a sample having a thickness of 1.6 mm × width 10 mm × length 135 mm, the afterflame time was measured according to UL-V94, and the flame retardancy was evaluated.
These evaluation results are shown in Table 2.

[Example 5]
Similar to Example 4 except that the phenolic polymer (II) obtained in Example 2 was used instead of the phenolic polymer (I) obtained in Example 1 and the blending ratio was as shown in Table 1. Then, a molding composition was prepared and evaluated. The results are shown in Table 2.

[Example 6]
Similar to Example 4 except that the phenolic polymer (III) obtained in Example 3 was used in place of the phenolic polymer (I) obtained in Example 1 and the blending ratio was as shown in Table 1. Then, a molding composition was prepared and evaluated. The results are shown in Table 2.

[Comparative Example 1]
Instead of the phenolic polymer (I) obtained in Example 1, a phenol aralkyl resin represented by the following general formula (4) (melt viscosity at 150 ° C. measured with an ICI melt viscometer is 100 mPa · s, hydroxyl equivalent 168 g) / Eq), and a molding composition was prepared and evaluated in the same manner as in Example 4 except that the blending ratio was as shown in Table 2. The results are shown in Table 2.

（式中、ｎは１〜１０の数）

(Where n is a number from 1 to 10)

In Table 1, when Examples 1-3 and Comparative Example 1 were contrasted, the polymers of Examples 1-3 were reduced in viscosity, had a high softening point, and were superior to the resin in Comparative Example 1.
In Table 2, the resin compositions of Examples 4 to 6 have the same gelation time and torque as those of Comparative Example 1, and there is no problem in molding curability. In addition, the resin compositions of Examples 4 to 6 had the same level of glass transition temperature as that of Comparative Example 1 while having a lower viscosity than Comparative Example 1, and the flame retardancy evaluation was equivalent to or higher than that of Comparative Example 1.

An object of the present invention is to provide a phenolic polymer composition suitable for semiconductor sealing applications having low melt viscosity and flame retardancy.
The phenolic polymer provided by the present invention is a phenolic polymer that is useful for molding materials, various binders, coating materials, laminated materials, and the like and has a low softening point and a low softening point.
The phenolic polymer provided by the present invention is particularly useful as an epoxy resin curing agent, and forms an epoxy resin composition excellent in low melt viscosity and flame retardancy particularly when used for semiconductor encapsulation. It is a phenolic polymer that can be used.
INDUSTRIAL APPLICABILITY According to the present invention, there is provided a method capable of easily and inexpensively producing a phenolic polymer composition suitable for semiconductor sealing applications having a low melt viscosity and flame retardancy.

Claims (11)

The molar ratio of the aromatic compound to the phenol is 0 with the phenol represented by the following general formula (1), the aromatic compound represented by the following general formula (2), the m-xylene / formaldehyde condensate, and formaldehyde. 0.1 to 0.6, the m-xylene / formaldehyde condensate is 5 to 25% by weight with respect to the phenols, and the molar ratio of formaldehyde to phenols is 0.01 to 0.20. Phenolic polymer obtained.

(In formula (1), R ¹ is hydrogen, an alkyl group having 1 to 6 carbon atoms or an aryl group, and in formula (2), X is a halogen, OH group or OCH ₃ group.)   The phenol polymer according to claim 1, wherein the ICI melt viscosity at 150 ° C is 10 to 200 mPa · s.   The phenolic polymer according to claim 1 or 2, wherein the phenol is phenol. The phenol represented by the following general formula (1), the aromatic compound represented by the following general formula (2), and the m-xylene / formaldehyde condensate have a molar ratio of the aromatic compound to the phenol of 0.1 to 0.1. After reacting under the condition that the m-xylene / formaldehyde condensate is 5 to 25% by weight with respect to the phenols, formaldehyde is further added at a molar ratio with respect to the phenols of 0.01 to 0.20. A method for producing a phenolic polymer obtained by condensation.

(In formula (1), R ¹ is hydrogen, an alkyl group having 1 to 6 carbon atoms or an aryl group, and in formula (2), X is a halogen, OH group or OCH ₃ group.)   The hardening | curing agent for epoxy resins which consists of a phenol type polymer in any one of Claims 1-3.   The epoxy resin composition containing the hardening | curing agent for epoxy resins which consists of a phenol type polymer in any one of Claims 1-3, and an epoxy resin.   Furthermore, the epoxy resin composition of Claim 6 containing an inorganic filler.   Furthermore, the epoxy resin composition of Claim 6 or 7 containing a hardening accelerator.   The epoxy resin composition according to any one of claims 6 to 8, which is used for semiconductor encapsulation.   The epoxy resin hardened | cured material formed by hardening | curing the epoxy resin composition in any one of Claims 7-9. The semiconductor device formed by sealing a semiconductor element using the epoxy resin composition of Claim 9.