WO2003037954A1

WO2003037954A1 - Phenolic resin, epoxy resin, process for producing the same, and resin composition for semiconductor encapsulation material

Info

Publication number: WO2003037954A1
Application number: PCT/JP2002/010859
Authority: WO
Inventors: Satoshi Mori
Original assignee: Nippon Petrochemicals Co.,Ltd.
Priority date: 2001-11-02
Filing date: 2002-10-18
Publication date: 2003-05-08
Also published as: JP3955199B2; JP2003137980A

Abstract

A phenolic resin or epoxy resin useful as a resin for semiconductor encapsulation materials, which gives a cured composition having an excellent balance among heat resistance, moisture resistance, crack resistance, and moldability. The phenolic resin is one which is obtained by reacting a phenol with an unsaturated cyclic hydrocarbon compound having two or more carbon-carbon double bonds in the presence of an acid catalyst and has a number-average molecular weight of 320 or lower in terms of polystyrene, and in which the content of monofunctional components having only one phenolic hydroxy group per molecule is 2 to 20 wt.%, excluding 2 wt.%, based on the resin.

Description

Technical Field Phenol resin, epoxy resin, production method thereof, and resin composition for semiconductor encapsulant

The present invention relates to a phenolic resin, an epoxy resin, and a semiconductor having an excellent balance of heat resistance, moisture resistance, crack resistance, and moldability, which are useful as an electrical insulating material, particularly a resin for a semiconductor sealing material and a resin for a laminated board. The present invention relates to a composition for a sealing material. Background art

In recent years, semiconductor-related technologies have advanced rapidly, and the required characteristics of each component and its raw material have become strict. In particular, the miniaturization of wiring and the increase in chip size have been progressing as semiconductor memory integration has increased, and the mounting method has also shifted from through-hole mounting to surface mounting. However, in automated lines for surface mounting, the semiconductor package is subject to sudden temperature changes during soldering of the lead wires, causing cracks in the resin molding for the semiconductor encapsulant and poor interface between the lead wire resins. There is a problem that moisture resistance is reduced.

As the phenol resin used in the resin composition for semiconductor encapsulant, a phenol resin such as a phenol novolak resin or a cresol novolak resin has conventionally been used as a curing agent, and a cresol nopolak skeleton has been used as a main agent. Epoxy resin is used. However, when these resins are used, there is a problem that the moisture absorption characteristics of the semiconductor package are poor, and as a result, the occurrence of cracks during immersion in the solder bath as described above is inevitable.

Therefore, recently, in order to improve the moisture resistance and heat resistance of a resin composition for a semiconductor encapsulant, an epoxy resin raw material and a curing agent for an epoxy resin have been used. Studies have been made to improve phenolic resins. For example, in JP-A-6-192615, phenolic resins are derived from phenols and dicyclopentene (hereinafter sometimes referred to as DCPD). An epoxy resin composition containing an epoxy resin as an essential component and having an excellent balance of moisture resistance, heat resistance and internal plasticity has been proposed. However, moldability is not always sufficient.

In Japanese Patent Application Laid-Open No. 9-48883, the amount of low molecular weight components is adjusted by distilling or reprecipitating an epoxy resin or a phenol resin as a raw material thereof in a DCPD / phenol-modified epoxy resin. Discloses that good fluidity can be obtained without impairing heat resistance. However, adjustment by distillation is difficult, and there are problems such as an increase in the amount of residual phenol in the resin. Further, since the adjustment by reprecipitation uses a solvent, there is a problem that it is necessary to remove the solvent from the resin again. The problem to be solved by the present invention is to provide a phenolic resin, an epoxy resin, and an efficient production method thereof, which are excellent in heat resistance after curing, have good fluidity, and are excellent in moldability when sealing a semiconductor. An object of the present invention is to provide an epoxy resin composition using the above resin. Disclosure of the invention

As a result of intensive studies to solve the above problems, the present inventors have found that, in the presence of an acid catalyst, a phenol and an unsaturated cyclic hydrocarbon having two or more carbon-carbon double bonds (hereinafter simply referred to as “unsaturated The phenolic resin obtained by the addition reaction of and has a number average molecular weight in terms of polystyrene of not more than 320 and only one phenolic hydroxyl group per molecule. Contains a suitable amount of monofunctional components (hereinafter sometimes simply referred to as “monofunctional components”), especially 1: 1 adducts of ether compounds or phenols with unsaturated cyclic hydrocarbons. In this case, it was found that the balance between heat resistance after curing and fluidity during molding was excellent. Furthermore, in the production of phenolic resins, the reaction method and reaction of phenols with unsaturated cyclic hydrocarbons By devising a method for concentrating the product, an efficient method for producing a phenol resin in which the content of the monofunctional component is controlled to an appropriate amount has been completed. That is, the present invention relates to a phenol resin obtained by reacting a phenol with an unsaturated cyclic hydrocarbon compound having two or more carbon-carbon double bonds, wherein the number average molecular weight in terms of polystyrene is 320 or less. And a phenolic resin characterized in that the content of a monofunctional component containing only one phenolic hydroxyl group in one molecule is more than 2% by mass and not more than 20% by mass in the resin.

Further, a reaction step of bringing a phenol into contact with an unsaturated cyclic hydrocarbon compound having at least two carbon-carbon double bonds in the presence of an acid catalyst, and a concentration step of mainly removing unreacted phenols In a method for producing a phenolic resin containing: a) the catalyst concentration in the reaction system is adjusted to a predetermined concentration in the reaction step, and the reaction product is concentrated under the predetermined conditions in the concentration step, whereby the number average molecular weight in terms of polystyrene is reduced. A phenolic resin characterized in that the content of the monofunctional component containing not more than 320 and one phenolic hydroxyl group in the resin is more than 2% by mass and not more than 20% by mass. It relates to a manufacturing method.

The present invention also relates to an epoxy resin obtained by reacting a phenol resin obtained by the above-mentioned production method with ephalohydrins.

Furthermore, an epoxy resin composition for a semiconductor encapsulant containing an epoxy resin, a curing agent comprising a phenol resin obtained by the above-mentioned production method, a curing accelerator and an inorganic filler as essential components, or an epoxy resin composition obtained by the above-mentioned production method. The present invention relates to an epoxy resin composition for a semiconductor encapsulant, comprising an epoxy resin, a curing agent, a curing accelerator and an inorganic filler as essential components. BEST MODE FOR CARRYING OUT THE INVENTION

Hereinafter, the present invention will be described in more detail.

The phenolic resin of the present invention comprises a phenol having a phenolic hydroxyl group and an unsaturated compound having two or more carbon-carbon double bonds in the presence of an acid catalyst. It is produced by reacting with a cyclic hydrocarbon compound.

Examples of unsaturated cyclic hydrocarbon compounds having two or more carbon-carbon double bonds include dicyclopentene, 4-vinylcyclohexene, 5-vinyl norborna-2-ene, 3a, 4, 7, 7a —Tetrahydroindene, α-binene, limonene and the like. These can be used alone or in combination. In particular, dicyclopentene is preferred because the resulting resin has excellent heat resistance, moisture resistance and mechanical properties.

The phenols are not particularly limited as long as they are aromatic compounds having a phenolic hydroxyl group in which a hydroxyl group is directly substituted on an aromatic ring, and examples thereof include phenol, o_cresol, and m-cresol. , P-cresol, o-ethylphenol, m-ethylphenol, p-ethylphenol, o-isopropylphenol, m-propylphenol, p-propylphenol, p_sec-butylphenol, p_tert-butylphenol Monovalent phenols such as, p-cyclohexylphenol, p-chlorophenol, o-bromophenol, m-bromophenol, p-bromophenol, α-naphthol, / 3-naphthol; resorcinol, catechol , Hydroquinone, 2,2-bis (4, -hydroxyphenyl) propane, 1,1, 1-bis (dihydroxyphenyl) methane, 1,1'-bis (dihydroxynaphthyl) methane, divalent phenols such as tetramethylbiphenyl, biphenyl, etc .; trishydroxyphenylmethane And other trivalent phenols. In particular, phenol, ο_cresol, m_cresol, α-naphthol, β-naphthol, and 2,2-bis (4'-hydroxyphenyl) propane are economical and easy to manufacture. It is preferable from the viewpoint of. These can be used alone or in combination.

The molar ratio between the unsaturated cyclic hydrocarbon and the phenol used in the reaction is appropriately adjusted depending on the molecular weight and melt viscosity of the desired phenol resin. Usually, the phenols / unsaturated cyclic hydrocarbons = 1 to 20 (molar ratio) are preferred. In particular, to lower the melt viscosity, phenols The range of the sum of the cyclic hydrocarbons = 2 to 15 (molar ratio) is preferable. The phenolic resin with low melt viscosity and the epoxy resin with low melt viscosity obtained by epoxidation can be used for semiconductor encapsulants because they can be filled with high filler and have low linear expansion coefficient. It is also preferable because the moisture resistance is improved.

Examples of the acid catalyst include inorganic acids such as hydrochloric acid, sulfuric acid and nitric acid, and organic acids such as formic acid, acetic acid and oxalic acid, boron trifluoride, boron trifluoride / ether complex, boron trifluoride / phenol complex, A Friedel-Crafts catalyst such as boron fluoride / water complex, boron trifluoride / alcohol complex, boron trifluoride / amine complex, or a mixture thereof is used. Among these, boron trifluoride, boron trifluoride / phenol complex, and boron trifluoride ether complex are preferably used in view of catalytic activity and ease of catalyst removal.

In the present invention, a monofunctional component having a number average molecular weight in terms of polystyrene of not more than 320 and containing only one phenolic hydroxyl group per molecule, particularly an ether type compound or phenols and an unsaturated cyclic hydrocarbon, (1) The content of the 1: 1 additive in the phenol resin is controlled to be more than 2% by mass and not more than 20% by mass. If the content is less than 2% by mass, the fluidity will be low, and if it exceeds 20% by mass, the heat resistance will be reduced, which is not preferable. The polystyrene reduced number average molecular weight is a number average molecular weight calculated from the molecular weight converted to the molecular weight of polystyrene having the same retention time in GPC measurement.

The method for producing a phenolic resin of the present invention includes a reaction step and a concentration step, both of which affect the amount of the monofunctional component.

Hereinafter, the monofunctional component and its control method will be described in detail. First, the reaction step will be described.

The concentration of the catalyst used in the reaction affects the reaction mechanism between the phenols and the unsaturated cyclic hydrocarbons and the position of addition, and therefore, the concentration of the catalyst is 0.01 relative to the total mass of the phenols, the unsaturated cyclic hydrocarbons, and the catalyst. ~ 0.5% by mass, and It is preferably in the range of 0.3 to 0.3% by mass. For example, when phenol and dicyclopentene are reacted in the presence of boron trifluoride / phenol complex, the total mass of phenol, dicyclopentene and boron trifluoride / phenol complex, Boron should be in the above range. When the catalyst concentration is more than 0.5% by mass, the reaction proceeds too fast. When the catalyst concentration is less than 0.01% by mass, the reaction progresses remarkably slow. It is not preferable because the control of the control becomes difficult.

It is necessary to maintain the catalyst concentration throughout the entire process of the reaction. Therefore, when phenols and a catalyst are charged into a reactor first and then reacted by dropwise addition of an unsaturated cyclic hydrocarbon, the catalyst concentration at the start of the reaction is practically the same as the concentration with respect to the phenols. However, the above range of the catalyst concentration is maintained from the start to the end of the reaction.

Further, in the above-mentioned catalyst concentration region, water affects the catalytic activity and the composition of the reaction product. If the amount of water is large, the catalytic activity decreases, and the progress of the reaction slows down. As a result, it becomes difficult to control the resin composition. Therefore, the water concentration in the phenols and unsaturated cyclic hydrocarbons before the addition of the catalyst before the start of the reaction is preferably 500 ppm or less. In particular, phenols easily contain water, so it is preferable to control the water by performing a dehydration operation as appropriate. Examples of the dehydration method include a method in which phenols are azeotroped with an organic solvent as necessary under a nitrogen stream.

The amount of the catalyst used and the amount of water in the raw material are not limited to the above ranges, and it is preferable to appropriately adjust the balance within a range where the resin composition can be controlled.

During the reaction, the inside of the reactor is usually replaced with an inert gas such as nitrogen or argon. The reaction is preferably performed in a closed system replaced with an inert gas, but the reaction can be performed in an open system while supplying the inert gas into the reactor. In the reaction, it is preferable that the amount of water in the reaction system is not more than 50 ppm by preventing water from entering the system. The reaction method is not particularly limited. For example, a predetermined amount of a phenol and an acid catalyst are charged into a reactor, and then the reaction is carried out by dropwise addition of an unsaturated cyclic hydrocarbon.

The reaction temperature may be appropriately adjusted according to the degree of progress of the reaction, and is not particularly limited. In the present invention, the reaction temperature is usually 30 to 150, preferably 50 to 120. By conducting the reaction in the range of ° C, the progress of the reaction can be favorably controlled.

The reaction time may be stopped when the amount of the monofunctional component in the resin reaches a desired amount, and is not particularly limited, but is usually from 10 minutes to 60 hours, preferably from 1 to 60 hours. The reaction can be carried out efficiently by conducting the reaction for 20 hours, more preferably for 2 to 10 hours.

The end point of the reaction is determined by confirming the resin composition in the reaction solution.

The reaction is terminated by deactivating the catalyst. It is important to ensure that the reaction is stopped. The means for deactivation is not particularly limited, but it is preferable to use a means for reducing the residual amount of ionic impurities such as boron and fluorine in the finally obtained phenol resin to 100 ppm or less. As the quenching agent, alkali bases such as alkali metals, alkaline earth metals or their oxides, hydroxides, carbonates, ammonium hydroxide, and ammonia gas can be used, but quick and simple treatment is possible. In addition, it is preferable to use hydrotalcites as a deactivator since the amount of ionic impurities remaining after the treatment is small.

In addition, when the phenolic resin of the present invention is used as a resin for a sealing material, it exhibits excellent curability and moldability, and provides excellent heat resistance and moisture resistance after curing. It is important to control physical properties as follows. The content of a compound containing two phenolic hydroxyl groups (hereinafter sometimes referred to as a binuclear component) in which two molecules of a phenol are added to one molecule of an unsaturated cyclic hydrocarbon is determined by the viscosity of the resin. Therefore, it is important to make appropriate adjustments since it has a significant effect on fluidity, curability, etc. The content of the binuclear component in the phenol resin is preferably from 30 to 90% by mass, and particularly preferably in the range of from 40 to 80% by mass. If the content of the binuclear component is less than 30% by mass, the fluidity of the resin decreases and moldability deteriorates. If the content is more than 90% by mass, the fluidity is good, but after curing. It is not preferable because the crosslink density decreases. The amount of the binuclear component can be controlled mainly by the reaction molar ratio of the phenols and the unsaturated cyclic hydrocarbon, and it is preferable to control the amount of the binuclear component by appropriately adjusting the molar ratio.

In addition, the viscosity of the resin greatly affects the flow characteristics at the time of molding, so it must be adjusted appropriately. Although there is no particular limitation on the viscosity, it is effective to grasp the solution viscosity of a 50% resin solution of n-butanol by, for example, the Canon-Fenske kinematic viscosity tube method. preferably to fall in the range of ^{^{1 0mm 2 / sec~ 20 0mm 2}} Z sec in by that solution viscosity law, preferred especially ^{3 0 mm 2 / sec~ 1 8} 0 mm 2 / sec controlled resin in the range of Exhibits flow characteristics.

In addition, the phenolic hydroxyl group content in the resin affects the curing characteristics and the like, and thus needs to be appropriately adjusted. The phenolic hydroxyl group content is not particularly limited, but is, for example, 165 gZe as the equivalent of the hydroxyl group in the resin measured by the reverse titration method of the acetylated compound in a pyridine-acetic anhydride solution. c! ~ 300 gZe Q is preferable, and especially resin adjusted to liO gZe (! ~ 250 g / e Q not only exhibits favorable curing characteristics but also has good balance with fluidity when molding. Handling is very good.

According to the production method described in the present specification, a phenol resin satisfying the above resin properties can be produced.

Next, the concentration step will be described.

The above reaction solution is treated in a concentration step after removing a deactivator or the like by filtration. In the concentration step, unreacted phenols are recovered and the amount of the monofunctional component is controlled, so that a phenol resin is obtained. The concentration conditions are Although certain conditions are not determined from the relationship between the temperature and pressure in the concentration system and the vapor pressure, the most efficient concentration can be achieved by performing the following conditions.

That is, the temperature in the system is not particularly limited as long as the resin does not decompose, but is preferably 250 or less, more preferably 180 to 220. is there.

Regarding the pressure in the system, it may be carried out under any of normal pressure, reduced pressure, and pressurized conditions.However, in order to smoothly and rapidly perform concentration in the above-mentioned temperature range, the pressure in the system should be reduced. preferable. Specifically, the range is preferably 66.5 kPa (500 torr) or less, and particularly preferably 40 kPa (300 torr) or less.

Further, in order to efficiently remove unreacted phenols in the resin, it is preferable to perform an operation of blowing nitrogen or high-pressure steam into the system under reduced pressure conditions.

The pressure of steam or nitrogen introduced into the system is not particularly limited, but specifically, is preferably in the range of 0.3 to 2.0 MPa, more preferably 0.5 to 1.5 MPa. Impurities can be removed efficiently when blowing operation is performed in the range of MPa.

The method of concentration is not particularly limited, but preferred examples of the concentration method include the following. After the filtered reaction solution (filtrate) is transferred to the concentration vessel, heating is started and the pressure inside the system is continuously reduced. When the pressure in the system reaches 200, the pressure in the system is reduced to full pressure, and the pressure is reduced to 13 kPa (100 torr) or less. After concentrating in this state for an arbitrary time, high-pressure steam is blown into the system under reduced pressure, and finally nitrogen is blown so that no steam remains, thereby completing the concentration.

The end point of the concentration is determined by confirming the amount of unreacted phenols and the amount of monofunctional components detected in the region of polystyrene reduced number average molecular weight of 320 or less by GPC analysis. The content of the monofunctional component in the phenolic resin should be more than 2% by mass and not more than 20% by mass. Is necessary. It is preferable that the content of unreacted phenols is low from the viewpoint of environmental considerations when using the product, but from the viewpoint of production efficiency and quality, the residual amount in the resin is 500 ppm or less. Is sufficient, preferably 20 ppm or less, more preferably 100 ppm or less. In other words, if the amount is more than 500 ppm, it is not preferable from the viewpoint of the performance of the resin and the influence on the environment.On the other hand, if the amount is less than 500 ppm, there is a problem that the concentration time becomes longer. It is important to take this into account.

As described above, the phenol resin of the present invention can be obtained by controlling the amount of the monofunctional component in the reaction step and the concentration step. Hereinafter, the monofunctional component will be specifically described in the case where phenol is used as the phenols and dicyclopentene is used as the unsaturated cyclic hydrocarbon.

In this case, the monofunctional component mainly includes a compound A represented by the following general formula (1) and a compound B represented by the following general formula (2).

Or

(2) Compound A and Compound B were separated by gel permeation (Chromatography) (GPC) and the components isolated by nuclear magnetic resonance (NMR, It can be identified by analyzing at a magnetic frequency of 400 MHz; Compound A was found to have an aliphatic hydrogen content of about 60% in the molecule by the following formula 1 from the results of 計算 -NMR measurement, and a chemical shift of phenolic hydroxyl group around 4.9 ρ pm. It can be identified by observing a single peak of origin. Also, it can be obtained from the ¹³ C-NMR measurement result by the following calculation formula 2.

Formula 1

Aliphatic hydrogen content of the molecule = A 1 / (A 1 + A 2) (A 1 is ¹ H- NMR measurement Chiya one Bok on chemical shift I 0 to 4. 8 p peak area intensity of pm, A 2 is the peak area intensity when the chemical shift on the ¹ H-NMR measurement chart is 6.5 to 8.5 ppm)

Formula 2

Ether-type product content = B 3 / (B 1 + B 2 + B 3) (B 1 is ¹³ C—chemical shift on NMR measurement channel 13 0 to 13 3 ppm area intensity , B 2 is ^{1 3} C-NMR measurement Chiya one bets on the chemical shift 1 3 7~: L 40 ppm of integrated intensity, B 3 is ^{1 3} C-NMR measurement Chiya one bets on the chemical shift 1 5 5 to; L 60 ppm area intensity)

Compound B can be identified by calculating the aliphatic hydrogen content in the molecule to be 76% from the following Formula 3 from iH_NMR measurement.

Formula 3

Aliphatic hydrogen content in molecule = C 1 Z (C 1 + C 2)

(C 1 is ¹ H- NMR peak area intensity of a chemical shift is Less than six p pm on measurement chart, C 2 is ¹ H- NMR measurement Chiya one bets on the chemical shift Bok force from 6.5 to 8. 5 ppm peak area intensity)

The contents of the compound A and the compound B in the phenol resin can be determined by measuring the amounts detected in a region corresponding to a polystyrene-equivalent number average molecular weight of 320 or less by GPC analysis.

In the reaction step, it is important to confirm the amount of compound A and compound B produced.At the end of the reaction step, the total content of compounds A and B If the content is more than 2% by mass and not more than 25% by mass of the total fat, the monofunctional components can be efficiently controlled in the subsequent concentration step, and their content is finally controlled to an appropriate amount. A phenolic resin can be obtained.

In the concentration step, by performing a high-pressure steam blowing operation under reduced pressure, the total content of compounds A and B in the resin can be more than 2% by mass and 20% by mass or less. Further, the total content of the compounds A and B is preferably set to 3 to 18% by mass.

In the method for producing a phenolic resin of the present invention, it is essential to perform the above-described reaction control and concentration control, and by performing these at the same time, a phenolic resin having a good balance of heat resistance and fluidity is obtained. be able to. The phenolic resin obtained as described above has excellent heat resistance, moisture resistance, crack resistance, and excellent flowability, and therefore has good moldability. It is useful as a curing agent for epoxy resins for boards or as a raw material for epoxy resins, but its use is not particularly limited.

Next, a method for producing the epoxy resin of the present invention will be described.

The epoxy resin of the present invention can be obtained by reacting the above phenol resin with ephalohydrins in the presence of a base catalyst to dalicidylate.

The glycidylation reaction can be performed by a conventional method. Specifically, for example, in the presence of a base such as sodium hydroxide and potassium hydroxide, usually at a temperature of 10 to L50, preferably at a temperature of 30 to 80, the phenol resin is converted to epichlorohydrin, It can be obtained by reacting with a daricidylating agent such as epibromhydrin, washing with water and drying.

The amount of the glycidylating agent to be used is preferably 2 to 20-fold molar equivalent, particularly preferably 3 to 7-fold molar equivalent to the phenol resin.

Further, at the time of the reaction, the water can be distilled off by azeotropic distillation with the glycidylating agent under reduced pressure, so that the reaction can proceed more quickly.

In addition, when the epoxy resin of the present invention is used in the electronic field, by-product chloride Salts such as sodium must be completely removed in the washing step. At this time, the unreacted dalicidylating agent may be recovered by distillation to concentrate the reaction solution, and then the concentrate may be dissolved in a solvent and washed with water. Preferred examples of the solvent include methyl isobutyl ketone, cyclohexanone, benzene, and butyl sorb. The concentrate washed with water is heated and concentrated. When the epoxy resin of the present invention is used as a resin for a sealing material, it exhibits excellent curability, moldability, etc., and imparts excellent heat resistance, moisture resistance, and the like after curing. It is important to control as follows.

The content of a compound in which two glycidyl groups are added to a binuclear component in a resin (hereinafter sometimes referred to as a binuclear epoxidation component) greatly affects the viscosity, flowability, and curability of the resin. Therefore, it is important to make appropriate adjustments. That is, the content of the binuclear epoxidation component in the epoxy resin is preferably from 30 to 90% by mass, particularly preferably from 40 to 80% by mass. If the amount is less than 30% by mass, the fluidity is reduced, which greatly affects the moldability of the cured product. If the amount is more than 90% by mass, good fluidity is obtained, but the crosslink density is reduced. It is not preferable because the curing characteristics are deteriorated. Since the viscosity of the resin greatly affects the flow characteristics during molding, it must be adjusted appropriately. Although there is no particular limitation on the definition of the viscosity, it is effective to grasp the solution viscosity of a 50% resin solution of 1,4-dioxane by, for example, the Canon-Fenske kinematic viscosity tube method. in solution viscosity by law, 1 0 0 mm ^2, sec more preferably in the range, in particular 7 0 mm ² / sec control compounds in the following ranges exhibit desirable flow properties.

The content of the epoxy group in the epoxy resin is usually from 200 to 500 g / eq, preferably from 250 to 450 g / eq. If the content of the epoxy group is 500 g ZeQ or more, the crosslinking density is too low, which is not preferable.

According to the production method described in the present invention, an epoxy resin satisfying the above physical properties Can be manufactured.

The epoxy resin thus obtained has excellent fluidity and good moldability as compared with an epoxy resin having a similar structure obtained by a conventional method. Further, since the concentration of the epoxy group is high, it is excellent in curability and heat resistance. Particularly, the semiconductor sealing material is extremely useful because of its advantages such as remarkably excellent solder crack resistance. It is also useful as a raw material of an epoxy resin composition for a laminate, and can be used as a varnish or the like for an electric laminate because of its excellent solubility of the epoxy resin in a solvent.

Further, an oligomer type epoxy resin obtained by modifying the epoxy resin of the present invention with a brominated polyphenol may be used for a laminate. Further, a resin having heat resistance imparted by blending or modifying a polyfunctional epoxy resin can also be used. In addition, in order to obtain a polymer type epoxy resin, the resin can be used as a raw material resin for a two-step method reaction. In addition, they are also useful for powder coatings, brake shoes, etc., and their uses are not particularly limited.

Next, the epoxy resin composition for a semiconductor encapsulant of the present invention will be described.

The epoxy resin composition of the present invention contains an epoxy resin, a curing agent, and an inorganic filler as essential components. The epoxy resin of the present invention is used as an epoxy resin, or the phenol resin of the present invention is used as a curing agent. It is characterized by being used.

When the epoxy resin of the present invention is used as the epoxy resin, another epoxy resin may be used in combination. As the other epoxy resin, any known epoxy resin can be used. For example, bisphenol A diglycidyl ether type epoxy resin, phenol novolak type epoxy resin, ortho cresol novolak type epoxy resin, bisphenol A nopolak type epoxy resin, bis Phenol F nopolak type epoxy resin, brominated phenol nopolak type epoxy resin, naphthol novolak type epoxy resin, biphenyl type bifunctional epoxy resin, etc. It is not specified.

Among these, an orthocresol novolak type epoxy resin is particularly preferable because of its excellent heat resistance, and a biphenyl type bifunctional epoxy resin is preferable because of its excellent fluidity. The above-mentioned other known epoxy resins can also be used as epoxy resins when the phenolic resin of the present invention is used as a curing agent.

As the curing agent, in addition to the phenolic resin of the present invention, all compounds that are commonly used as curing agents for epoxy resins can be used, and are not particularly limited. Examples thereof include diethylenetriamine and triethylene. Aliphatic amines such as lentetramine, aromatic amines such as metaphenylenediamine, diaminodiphenylmethane, diaminodiphenylsulfone, phenol novolak resin, orthocresol nopolak resin, bisphenol A novolak resin, bis Phenol F-nopolak resin, phenols-di-cyclopentene polyaddition resin, dihydroxyxnaphtalene nopolak resin, polyhydric phenols with xylidene as a bonding group, phenolaralkyl resins, naphthol resins, Polyamide resins and their modifications Anhydrides such as maleic anhydride, maleic anhydride, hydrofluoric anhydride, hexahydrophthalic anhydride, pyromellitic anhydride, etc., dicyandiamide, imidazole, boron trifluoride, amine complexes, guanidine derivatives, etc. Latent curing agents and the like.

Above all, for semiconductor encapsulants, aromatic hydrocarbon-formaldehyde resins such as the above-mentioned phenol nopolak resins are excellent in heat resistance and moldability, and phenol aralkyl resins are excellent in heat resistance, moldability and low water absorption. It is preferred because of its superiority.

The amount of the curing agent used is not particularly limited as long as it provides sufficient heat resistance to the epoxy resin composition.Preferably, the number of epoxy groups contained in one molecule of the epoxy resin and the amount of the curing agent This is the amount at which the number of active hydrogens becomes close to the equivalent.

In addition, a curing accelerator can be appropriately used. As a curing accelerator Any known compounds can be used.Examples include phosphorus compounds, tertiary amines, imidazoles, metal salts of organic acids, Lewis acid / amine complex salts, and the like. These may be used alone or in combination of two or more. Combinations are also possible.

The inorganic filler enhances the mechanical strength and hardness of the semiconductor encapsulating material, achieves a low water absorption and a low coefficient of linear expansion, and can enhance the crack preventing effect.

The inorganic filler used is not particularly limited, and examples thereof include fused silica, crystalline silica, alumina, talc, clay, and glass fiber. Among these, fused silica and crystalline silica are generally used especially for semiconductor encapsulating materials, and fused silica is preferred because of its excellent fluidity. Spherical silica, pulverized silica and the like can also be used.

The blending amount of the inorganic filler is not particularly limited, but is preferably in the range of 75 to 95% by mass in the composition. Particularly, in a semiconductor encapsulant application, the solder crack resistance is extremely low. This range is preferable because it is excellent. In the present invention, even if it is 75% by mass or more, fluidity and moldability are not impaired at all.

In addition to the above components, various known additives such as a coloring agent, a flame retardant, a release agent, and a staple coupling agent can be appropriately compounded as necessary. Semiconductor encapsulating materials include brominated epoxy resins such as tetrabromo A-type epoxy resin and brominated phenol nopolak-type epoxy resin, flame retardants such as antimony trioxide and hexabromobenzene, carbon black and red iron. It is preferable to appropriately add a coloring agent, a female agent such as a natural wax and a synthetic wax, and an additive such as a low stress additive such as silicone oil, synthetic rubber and silicone rubber.

To prepare a molding material using each of the above components, an epoxy resin, a curing agent, and an inorganic filler, as well as a curing accelerator and other additives were sufficiently mixed with a mixer or the like. Thereafter, the mixture is melted and kneaded with a hot roll or a kneader, and then subjected to injection molding or cooling followed by grinding.

[Example]

Next, the present invention will be specifically described with reference to Production Examples, Examples and Comparative Examples. You.

The properties of the phenol resin were measured by the following methods.

1) Compound A content (% by mass)

Compound A was isolated and purified from phenolic resin using preparative GPC, open column, etc., and identified using NMR and the like. In addition, if the aromatic hydrocarbon solvent is not used in the synthesis, the component detected during the retention time corresponding to Compound A (polystyrene-equivalent number average molecular weight of not less than 230 and less than 320) Is measured in advance, and the measured amount is subtracted from the amount of the retention time component when synthesized using an aromatic hydrocarbon solvent, and the area is calculated from the measurement chart of the entire phenol resin. From the ratio, the content of compound A with respect to the entire phenol resin was determined. The measurement was performed using a 1% by mass solution of phenolic resin in tetrahydrofuran (THF) using a high-performance liquid chromatography system “Millennium” manufactured by WATERS.

2) Content of compound B (% by mass)

Compound B was isolated and purified from phenolic resin using preparative GPC, open column, etc., and identified using NMR and the like. In addition, the amount of the component corresponding to Compound B (substance detected in the range of polystyrene-equivalent number average molecular weight of 100 or more and less than 230) using analytical GPC was measured, and the measurement chart for the entire phenol resin was measured. From the area ratio of, the content of compound B with respect to the entire phenol resin was determined. The measurement was performed using a 1% by mass solution of a phenolic resin in tetrahydrofuran (THF) using a high-performance liquid mouth chromatography system “Millennium” manufactured by WATERS.

3) OH equivalent

The phenol resin obtained in the production was heated and refluxed in a mixed solution of pyridine and acetic anhydride, and the solution after the reaction was determined by back titration with a hydration power rim.

4) Softening point

It was measured according to the ring and ball softening point measurement method described in JISK2207. 5) Solution viscosity of 50% by mass n-butanol solution

A n-butanol solution having a solid content concentration of 50 ± 0.01% was used, and the measurement was carried out at a constant-temperature bath water temperature of 25 using a backflow type Canon Fenske viscometer.

6) 50% by mass solution viscosity of 1,4-dioxane solution

A 1,4-dioxane solution having a solid concentration of 50 ± 0.01% was prepared and measured with a reverse-flow type Canon Fenske viscometer at a constant temperature water temperature of 25 :.

7) Amount of binuclear component and amount of binuclear epoxidation component

Using a 1% by weight phenol resin in THF solution, detection was performed with a differential refraction detector “WAT ERS 410” manufactured by WATE RS, and measured using the company's high-performance liquid chromatography system “Millennium”. .

[Production of phenolic resin (I)]

To a four-necked flask equipped with a stirrer and a thermometer, 150 g of phenol was added with 100 g of toluene, and azeotropic dehydration was performed to reduce the water content of the phenol to 400 ppm. 1.5 g of boron trifluoride / phenol complex was added to 105 g (11.1 mol) of the phenol, and the mixture was sufficiently stirred. Thereafter, while stirring, 188 g (1.4 mol) of dicyclopentene was added over 2 hours while maintaining the system temperature at 70 X :. Thereafter, the temperature inside the system was raised to 100, and then the heating and stirring were maintained for 2 hours. After lowering the temperature in the system to 90 ^, 8 g of talcite “KW-1000” (trade name, manufactured by Kyowa Chemical Industry Co., Ltd.) was added to the obtained reaction product solution. To inactivate the reaction. The reaction solution was filtered, the temperature was raised to 190 while unreacted phenol was recovered by distillation from the resulting solution, and nitrogen bubbling was performed under a reduced pressure of 13 kPa (lOOtor), and the mixture was maintained for 3 hours. As a result, 411 g of a reddish brown phenol resin (I) was obtained.

The content of Compound A and Compound B in this resin was 2.5% by mass and 3.2% by mass, respectively. The content of the binuclear component was 63% by mass. When each physical property of this resin was measured, the softening point was 87 and the hydroxyl equivalent was 177 g / eQ. n-butanol The solution viscosity was 86 mm ² sec.

Manufacturing Example 2>

[Production of epoxy resin (I)]

(Dalicidylation reaction)

A 3-liter 4-neck flask equipped with a stirrer, a reflux condenser and a thermometer was charged with 177 g of the phenolic resin (I) produced in Production Example 1 and 400 g of epichlorohydrin, followed by stirring. Dissolved. The pressure in the reaction system was adjusted to 20 kPa (150 torr), and the temperature was raised to 68. The reaction was carried out for 3.5 hours while continuously adding 100 g of an aqueous solution of sodium hydroxide having a concentration of 48% by mass. The water produced by the reaction and the aqueous sodium hydroxide solution were decomposed by refluxing an azeotrope of water-hydrazine hydrin and continuously removed out of the reaction system. After completion of the reaction, the pressure of the reaction system was returned to normal pressure, and the temperature was raised to 110 to completely remove water from the reaction system. Excess epichlorohydrin was distilled off under normal pressure, and further distilled at 140 under a reduced pressure of 2 kPa (15 torr).

(Washing)

To a mixture of the resulting resin and sodium chloride, 300 g of methyl isobutyl ketone and 36 g of a 10% by mass aqueous sodium hydroxide solution were added, and the mixture was reacted at 85 for 1.5 hours. After the completion of the reaction, 750 g of methyl isobutyl ketone and 300 g of water were added, and the lower aqueous solution of the inorganic salt was separated and removed. The separation between the oil and water layers was very good.

Next, 150 g of water was added to the methyl isobutyl ketone liquid layer for washing, neutralized with phosphoric acid, and the aqueous layer was separated, and further washed with 800 g of water to separate the aqueous layer.

After quantitatively recovering the inorganic salts, the methyl isobutyl ketone liquid layer was distilled under normal pressure, followed by vacuum distillation at 0.67 kPa (5 torr) and 140 ° C to obtain 2 16 g of epoxy resin (I) was obtained.

The epoxy resin obtained had an epoxy equivalent of 269 gZe Q, a 1,4-dioxane 50% by mass solution viscosity of 22 mm ² / sec, and a binuclear epoxy. The content of the silicified component was 51% by mass.

Comparative Manufacturing Example 1>

[Production of phenolic resin (II)]

The reactor was charged with phenol and toluene, heated to 160 to azeotrope with toluene, and toluene was distilled off. Sampling is performed as appropriate to confirm that the water content of the phenol in the system is 10 O ppm or less, and then to 100 g (11.2 mol) of the dehydrated phenol is added to trifluoride. After adding 15 g of boron-phenol complex to make it homogeneous, 188 g (1.4 mol) of dispenser was slowly added dropwise over 1 hour while maintaining the liquid temperature at 80. After completion of the dropwise addition, the temperature was raised to 140 and the mixture was further stirred for 3 hours.

It was confirmed that the water content was less than 100 ppm by separately measuring dicyclopentene and the like. The water content of the reaction system was also measured appropriately, and it was confirmed that the water content was 100 ppm or less.

The reaction solution was cooled to 90, and 50 g of magnesium hydroxide / aluminum hydroxide / hydrite talcite (Kyowa Word 100,000) was added to deactivate the catalyst. The reaction was filtered. The obtained filtrate was distilled and concentrated at 190 under a reduced pressure of 13 kPa (lOOtrr) for 5 hours to obtain 415 g of a phenol resin (II).

The obtained phenol resin had a softening point of 95.0 and a phenolic hydroxyl equivalent of 170 g / eQ.

According to GPC measurement, the content of compound A in the phenol resin was 1.1% by mass, and the content of compound B was 0.4% by mass. Further, the content of the binuclear component was 65% by mass, and the solution viscosity of 50% by mass of n-butanol was 90 mm ² / sec.

Manufacturing Comparative Example 2>

[Manufacture of epoxy resin (II)]

Production was performed in the same manner as in Production Example 2 except that 170 g of the phenolic resin (II) produced by the method of Production Comparative Example 1 was used. Resin (II) was obtained.

The epoxy equivalent of the obtained epoxy resin was 2663 gZe Q, the content of the binuclear epoxidation component was 53% by mass, and the solution viscosity of 50% by mass of 1,4-dioxane was 26 mm ² / sec. there were.

Production Comparative Example 3>

[Production of phenolic resin (III)]

The reaction was carried out in the same manner as in Production Example 1 except that phenol having a water content of 950 ppm after azeotropic dehydration was used, to obtain 408 g of a phenol resin (III).

The softening point of this resin was 84, and the hydroxyl equivalent was 301 g / eQ. The solution viscosity of the 50% by mass n-butanol solution at 25 ° C. was 64 mm ² Zsec. The resin contained 6.3% by mass of compound A and 16.9% by mass of compound B.

The content of the binuclear component was 51% by mass.

Comparative Manufacturing Example 4>

[Production of epoxy resin (III)]

(Glycidylation reaction)

A 3-liter 4-neck flask equipped with a stirrer, reflux condenser and thermometer was charged with 301 g of the phenolic resin (III) produced in Production Comparative Example 3 and 680 g of epichlorohydrin, and then stirred. , Dissolved. The pressure in the reaction system was adjusted to 2 OkPa (150 torr), and the temperature was raised to 68X :. The reaction was continued for 3.5 hours while continuously adding 170 g of a 48% by mass aqueous sodium hydroxide solution thereto. The water produced by the reaction and the aqueous sodium hydroxide solution were decomposed by refluxing an azeotropic mixture of water and epichlorohydrin, and were continuously removed to the outside of the reaction system. After completion of the reaction, the pressure of the reaction system was returned to normal pressure, and the temperature was raised to 110 to completely remove water from the reaction system. Excess epichlorhydrin was distilled off under normal pressure and further distilled at 140 under reduced pressure of 2 kPa (15 torr).

(Washing)

The resulting resin, a mixture of sodium chloride, and methyl isobutyl ketone 500 g and 60 g of a 10% by mass aqueous sodium hydroxide solution were added, and the mixture was reacted at 85 t: for 1.5 hours. After the completion of the reaction, 100 g of methyl isobutyl ketone and 300 g of water were added, and the lower layer aqueous solution of an inorganic salt was separated and removed. The separation between the oil and water layers was very good.

Next, 300 g of water was added to the methyl isobutyl ketone liquid layer for washing, neutralized with phosphoric acid, and the aqueous layer was separated, and then further washed with 80 Og of water to separate the aqueous layer.

After quantitatively recovering the inorganic salts, the methyl isobutyl ketone liquid layer was distilled under normal pressure, followed by distillation under reduced pressure at 0.67 kPa (5 torr) and 140. 7 g of epoxy resin (III) was obtained.

The obtained epoxy resin had an epoxy equivalent of 34.1 g Zeq, a 1,4-dioxane of 50% by mass, a solution viscosity of 12 mm ² , sec, and a binuclear epoxidized component of 42% by mass. Met.

Using the phenolic resin manufactured so far, we compared the fluidity and curability of the epoxy resin composition. The mixture prepared according to the composition shown in Table 1 was kneaded with a hot roll for 100 minutes and 8 minutes, and then ground to 12 to 14 MPa (1200 to 140 kgcm). ² ) A tablet is created with the pressure of ² ), and using this, a plunger pressure of 0.8 MPa (80 kgZc m ² ), a mold temperature of 175 and a molding time of 1 Sealing was performed under the condition of 00 seconds, and a flat package having a thickness of 2 mm was prepared as a test piece for evaluation. Thereafter, post-curing was performed at 175 for 8 hours. The epoxy resin composition 1 7 using the test mold and gel time as an indicator of flowability of 5T :, 0. 7 MP a (7 0 kg / cm 2), the measurement of the spiral flow of 1 2 0 sec conditions went. In addition, the glass transition temperature was measured by DMA as an index of hardening using the test specimen for evaluation. At 85, the sample was left in an atmosphere of 85% RH for 16 hours to perform a moisture absorption treatment, and the water absorption was measured. Further, after that, the crack occurrence rate when immersed in a solder bath at 260 for 10 seconds was examined. Table 1 shows the results. Example 1 The fluidity and heat resistance are well-balanced. Comparative Example 1 has poor fluidity, and Comparative Example 2 has poor heat resistance.

As the phenol nopolak, evening manol 758 (manufactured by Arakawa Chemical Co., Ltd., softening point: 83, hydroxyl equivalent: 104 g ZeQ) was used. Orthocresol L-novolak epoxy used was ESCN-220L (manufactured by Sumitomo Chemical Co., Ltd., having a softening point of 66 and an epoxy equivalent of 212 g / eq).

【table 1】

A comparison was made of the fluidity and curability of a composition using an epoxy resin made from phenolic resin. The mixture prepared according to the composition shown in Table 2 was kneaded with a hot roll at 100 for 8 minutes and then pulverized. Things to 1 2~: L 4MP a (1 2 0 0~ 1 4 0 0 kgcm 2) Te a pressure of evening to create a breccias bets, plunger pressure 0. 8 MP a by transfer molding machine using the same (80 kg / cm ² ), mold temperature: 17.5: Molding time: 100 seconds, sealing was performed, and a flat package with a thickness of 2 mm was prepared as an evaluation test piece. Thereafter, post-curing was performed at 175 for 8 hours. 1 7 5 using the gel time and the test mold as an indication of the flowability of the epoxy resin composition, 0. 7 MP a (7 0 kg Roh cm ^2), we measured the spiral flow conditions 1 2 0 sec Was. Using the test specimen for evaluation, the glass transition temperature was measured by DMA as an index of curability. At 85, the sample was allowed to stand in an atmosphere of 85% RH for 16 hours, subjected to moisture absorption treatment, and measured for water absorption. Further, after that, the crack generation rate when immersed in a solder bath at 260 for 10 seconds was examined. Table 2 shows the results. Example 2 has a good balance between fluidity and heat resistance, Comparative Example 3 has poor fluidity, and Comparative Example 4 has poor heat resistance.

The phenol novolak used was phenolic TD-213 (manufactured by Dainippon Ink and Chemicals, Inc., softening point: 80, hydroxyl equivalent: 104 gZeQ).

[Table 2]

Industrial applicability

According to the present invention, a phenolic resin composition, an epoxy resin composition, and a semiconductor encapsulant having good fluidity, excellent moldability when encapsulating a semiconductor, and further having excellent heat resistance after encapsulation and curing are provided. A stop material can be provided.

Claims

The scope of the claims

1.The phenolic resin obtained by reacting phenols with an unsaturated cyclic hydrocarbon compound having two or more carbon-carbon double bonds has a polystyrene equivalent number average molecular weight of not more than 320, A phenol resin characterized in that the content of the monofunctional component containing only one phenolic hydroxyl group in one molecule is more than 2% by mass and not more than 20% by mass of the resin.

2. The phenolic resin according to claim 1, wherein the phenol is phenol, and the unsaturated cyclic hydrocarbon compound having two or more carbon-carbon double bonds is dicyclopentene.

3.—The functional component contains at least a compound A represented by the following general formula (1) and a compound B represented by the general formula (2), described in claim 2. Phenolic resin.

Or

(2)

4. A reaction step of contacting a phenol with an unsaturated cyclic hydrocarbon compound having two or more carbon-carbon double bonds in the presence of an acid catalyst, and a concentration step of mainly removing unreacted phenols In a method for producing a phenolic resin containing a phenol resin, the concentration of the catalyst in the reaction system is adjusted to a predetermined concentration in the reaction step, and the reaction product is concentrated under predetermined conditions in the concentration step, whereby the number average molecular weight in terms of polystyrene is reduced. 3 0 or less, or A method for producing a phenol resin, wherein the content of a monofunctional component having only one phenolic hydroxyl group in the resin is more than 2% by mass and not more than 20% by mass.

5. The method for producing a phenolic resin according to claim 4, wherein the acid catalyst used in the reaction step is a boron trifluoride / phenol complex.

6. The amount of acid catalyst used is 0.01 to 0.5% by mass based on the total amount of phenols, unsaturated cyclic hydrocarbon compounds having two or more carbon-carbon double bonds, and acid catalyst. 6. The method for producing a phenolic resin according to claim 4 or claim 5, characterized in that:

7. The method for producing a phenol resin according to any one of claims 4 to 6, wherein the water concentration in the phenols before the addition of the acid catalyst is 500 ppm or less.

8. In the concentration step, after reducing the pressure to 40 kPa (300 torr) or less, by blowing high-pressure steam, the residual amount of unreacted phenols in the resin is reduced to 500 ppm or less. Item 8. The method for producing a phenolic resin according to any one of Items 4 to 7.

9. The phenol according to any one of claims 4 to 8, wherein the phenol is a phenol, and the unsaturated cyclic hydrocarbon compound having two or more carbon-carbon double bonds is dicyclopentene. Method for producing phenolic resin described in

10. In the concentration step, after reducing the pressure to 40 kPa (300 torr) or less, by blowing high-pressure steam, the total content of the compounds A and B in the resin exceeds 2% by mass to 20% by mass. 10. The method for producing a phenolic resin according to claim 9, wherein:

1 1. An epoxy resin obtained by reacting the phenolic resin according to any one of claims 1 to 3 with an epihalohydrin.

12. Production of a phenolic resin by the production method according to any one of claims 4 to 10, and then production of an epoxy resin by reacting the phenolic resin with ephalohydrins in the presence of a base catalyst. Method.

13. Including epoxy resin, curing agent, curing accelerator and inorganic filler as essential components An epoxy resin composition for a semiconductor encapsulant, wherein the curing agent is the phenolic resin according to any one of claims 1 to 3.

1 4. An epoxy resin composition for a semiconductor encapsulant, comprising the epoxy resin according to claim 11, a curing agent, a curing accelerator, and an inorganic filler as essential components.