JPS6063218A - Bromine-containing novolak-type phenolic resin glycidyl ether and sealing compound consisting mainly of the same - Google Patents

Abstract

PURPOSE:To obtain the titled product with high heat resistance and flame-retardancy, suitable as sealing compounds for semiconductor integrated circuit, by using bromine-contg. phenol as one component of the phenolic ones to form molecular end and regulating the bromine content within a specific range. CONSTITUTION:A monofunctional phenol of formula I (R3 and R4 are each H, 1-10C alkyl, halogen or aromatic group)is made to react with a saturated aldehyde of formula R6CHO (R6 is H or 1-4C alkyl) using basic catalyst to effect resol formation followed by poly condensation, in the presence of acid catalyst, with a di- or trifunctional phenol of formula II (R1, R2, and R5 are each H, 1-10C alkyl halogen or aromatic group). Said phenolic resin is made into its glycidyl ether by the reaction with an epihalohydrin, thus obtaining the objective product having recurring unit of formula III and molecular chain end of formula IV (R7 is H or 1-4C alkyl) with a bromine content 3-40wt% and a number-average recurring unit number 1-40.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a novel glycidyl ether of a bromine-containing noyglac type phenolic resin which is particularly useful as a sealing material for semiconductor integrated circuits, and its uses.

It is used as a sealing material for semiconductor integrated circuits, and its physical properties such as high heat resistance, low t:3 and low water-decomposable bromine content are important. Glycidyl ether-based tetrabromobisphenol, which is generally used as a flame retardant type, has a high bromine content and is excellent in self-extinguishing properties, but it has low heat resistance in the sense that the glass transition temperature of the molded product is low. Therefore, it does not meet the physical properties required for a sealing material.

Brominated epoxy novolac resins obtained by brominating novolaks and then reacting them with epichlorohydrin have also been proposed as flame-retardant types. (Japanese Patent Publication No. 50-10685) However, this resin has the drawback of having a high content of hydrolyzable bromine. The reason for this is that when novolaks are brominated, carbons other than the phenyl nucleus, such as carbons in the methylene chain, are also brominated. Although this resin has a higher glass transition temperature when molded than glycidyl ether of tetrabromobisphenol, it is still insufficient for use as a sealing material because of its large epoxy equivalent.

The present inventors have proposed that this J: STt
As a result of intensive research into glycidyl ether of polyhydric phenol, the invention was finally discovered.

That is, in the present invention, substantially all of the molecular chain ends of a substantially monolinear polymer having general formula (I) as a 4% return unit have general formula (11) (in which I
L and ~R1i are the same or different groups selected from the group consisting of a hydrogen atom, an alkyl group having 1 to 10 carbon atoms, an aromatic group, and 10 atoms; , R7 are the same or different groups selected from the group consisting of hydrogen atoms and alkyl groups having 1 to 4 carbon atoms. ) It is a sealing agent that is modified with a phenyl nucleus represented by the following formula, has a bromine content of 3 to 4 Qwt%, and has a number average repeating unit as a main component. The present invention will be explained in detail below.

The second feature of the glycidyl ether structure of the novel bromine-containing novolak phenol resin of the present invention is that no bromine atom is bonded to the carbon atom of the methylene chain.

Specific examples of the substituent R1 of the present invention include hydrogen atom, methyl group, ethyl group, phenyl group, benzyl group, t
-butyl group, bromine atom, etc., preferably the substituent and ~It4 is a hydrogen atom or a methyl group, and 几 is a hydrogen atom, a methyl group, a t-butyl group, or a bromine atom; The range is not limited to these.

Specific examples of the substituent groups of the present invention include hydrogen atoms, methyl groups, ethyl groups, propyl groups, etc.
The scope of the present invention is not limited thereto. The number average number of repeating units of the glycidyl ether of the bromine-containing novolac type phenol resin of the present invention is 1 or more and 40 or less. When the number of units exceeds 40, the viscosity becomes high even under high temperature conditions, and the processability during molding decreases. However, if the number of units is less than 1, problems such as a decrease in heat resistance will occur.

The bromine content of the glycidyl ether of the bromine-containing novola-type phenolic resin of the present invention is 8 to 40 wt%. The higher the bromine content, the higher the congestion flammability, but if the bromine content exceeds 4 Qwt%, the epoxy equivalent will increase, and as a result, the number of crosslinking points in the cured molded product will decrease and the heat resistance will decrease. Further, if the bromine content is less than 3 wt%, a sufficient flame retardant effect cannot be obtained. In terms of the balance between flame retardancy and X heat resistance,
The preferred bromine content is 3-7 wt%.

The glycidyl ether of the bromine-containing novolac type phenolic resin of the present invention is heated to 7q°C by applying a known method for producing glycidyl ether of a novolak phenol resin, except for the phenol component. .

(i) (a) General formula (in the formula, R3 and 几 are the same or different selected from the group consisting of a hydrogen atom, an alkyl group having 1 to 10 carbon atoms, an aromatic group, and a halogen atom; at least one bromine-containing functional phenol component represented by the general formula (tV)R60uO(IV) (R6 is a hydrogen atom, an alkyl group having 1 to 4 carbon atoms) (b) The resol-formed functional phenol component and the general formula (V) (wherein, R2 and R5 are hydrogen Atom, carbon number 1-10
They are the same or different groups selected from the group consisting of alkyl groups, aromatic groups, and halogen atoms. ) Condensation polymerization with at least one saturated aldehyde component represented by the bifunctional formula (IV) to obtain a bromine-containing novolac type phenol resin, (11) Next, the phenol resin is glycidyl etherified with shrimp halohydrin. It can also be preferably produced by a novel method for producing glycidyl ether of bromine-containing novolacliphenol resin.

This manufacturing method will be explained below.

In the first step, the bromine-containing-functional phenol component is converted into a resol using a saturated aldehyde component and a basic catalyst. The basic catalyst at this time is preferably an alkali metal or alkaline earth metal hydroxide, but other basic catalysts may also be used. In the second step, the resol compound and a phenol component selected from a difunctional phenol component and a trifunctional phenol component are converted into novolak by an acidic catalyst and a saturated aldehyde component further added as the case requires.

The saturated aldehyde component optionally added in this step may be the same as or different from that in the first step.

Examples of acidic catalysts include hydrochloric acid, oxalic acid, formic acid, sulfuric acid, orthophosphoric acid, benzenesulfonic acid, and paratoluenesulfonic acid! ! Although preferred, other acidic catalysts may also be used.

Specific examples of trifunctional phenol components include phenol, m-cresol, m-ethylphenol, m-isopropylphenol, 3-n-propylphenol,
3-chlorophenol, 3-bromophenol, 3.5
-xylenol, 3,5-dichlorophenol, or 3-chloro, 5-methylphenol, etc.
The scope of the present invention is not limited to these.
-propenylphenol, 0-benzylphenol, 5
- n-amyl-m-cresol, O-cresol, P
-Cresol, 0-ethylphenol, P-ethylphenol, 0-phenylphenol, p-phenylphenol, I) -L-pentylphenol, p-t-butylphenol, 0-chlorophenol, 4-chloro-
Examples include 3,5-xylenol, O-allylphenol, nonylphenol, P-bromophenol, O-bromophenol, etc., but the scope of the present invention is limited to these, and examples include 2,4-dibromophenol. ,
2.6-dibromophenol, 2.8.4-tribromophenol, 2.4.5-1-ribromophenol, 2
, 4-dibromo-3-methylphenol, etc., but the scope of the present invention is not limited thereto.

Examples of saturated aldehyde components include formaldehyde, acetaldehyde, and fluorine, but the scope of the present invention is not limited thereto.

The difunctional phenol component and the trifunctional phenol component may be used alone or in a mixture of two or more, and the difunctional phenol component and the trifunctional phenol component may be used as a mixture. You can use it as well.

Similarly, the bromine-containing functional phenol component may be a single n-compound or a plurality of n-compounds. The usage ratio of phenols selected from bifunctional phenolic components, trifunctional phenols and phenolic components, and phenols selected from bromine-containing-functional phenolic components is 30% each.
~95 mol% and 5 to 70 mol% (however, the total of both phenolic components is 100 mol%).

The number average number of repeating units is approximately determined by this usage ratio, and the above ratio range corresponds to ζJ~40 in terms of the number average number of repeating units.

The amount of the saturated aldehyde component used relative to the total L0 mole of all phenolic components is usually 0.25 to 095 mole. However, depending on the reaction conditions, a large amount of unreacted aldehyde components may remain, so it is also possible to use a larger amount of the autophase aldehyde component than the above ratio in this reaction.

The bromine-containing novolac-type phenol resin obtained in the second step is then glycidyl etherified to obtain the glycidyl ether of the present invention. As a method for this glycidyl etherification, a method commonly used for producing glycidyl ether from -valent or polyvalent phenol can be applied. For example, polyphenols are dissolved in epichlorohydrin, an aqueous alkali metal hydroxide solution is continuously added to this solution, water and epichlorohydrin are distilled from the reaction mixture, and the distilled liquid is separated to form an aqueous layer. In a production method in which epichlorohydrin is removed and returned to the reaction system, a product can be produced by using a bromine-containing novolac-type substituted phenol resin instead of polyhydric phenols. Note that this reaction can also be carried out in the presence of a cyclic or linear ether. Specific examples of ether compounds include dioxane and jetoxyethane, but the scope of the present invention is not limited thereto.

The glycidyl ether of the present invention thus obtained has characteristics such as high heat resistance, low hydrolyzable bromine, as well as flame retardancy, and is useful in various uses. The usage will be explained below.

The composition containing glycidyl ether of bromine-containing novolac type phenolic resin and a curing agent of the present invention has the characteristics of heat resistance, flame retardance, and low hydrolyzable bromine content, and is suitable for semiconductor integration as exemplified below. It is useful in many applications including circuit encapsulation materials.

Specific examples of curing agents include phenol novolac, diaminodiphenylmethane, diaminodiphenyl sulpon,
Metaphenylene diamine, phthalic anhydride, tetrahydrophthalic anhydride, pyromelli anhydride, 1 acid, benzophenone tetracarboxylic anhydride, ■-cresol novolac, dicyandiamide, hexahydrophthalic anhydride, diethyltriamine, triethylenetriamine, tetraethylenepentamine, Menthanediamine, [1-aminoedylpiperazine, meta-xylene diamine, meta-aminobenzylamine, benzine, 4-coulolo-phenylene diamine, bis(3,4-diaminophenyl) sulfone, 2
．． 6 diaminopyridine 4E, but the present invention is not limited thereto.

Further, a bromine-containing novolac type phenol resin, which is an intermediate of the glycidyl ether of the present invention, can also be used as a curing agent.

In addition to the curing agent, the glycidyl ether of the novolac-type phenolic resin containing % element of the present invention includes ordinary fillers such as silica, alumina, talc, clay, glass fiber, imidazole neck, 3X and amines, phenol neck, etc. A hardening accelerator, stearic acid, calcium stearate, internal mold release agent such as carnauba wax, montan wax, etc. are blended and used as a sealant, especially a sealant for semiconductor integrated circuits. Transfer molding is generally used for molding. The amount of curing agent, etc. to be blended varies depending on the oil, but it is usually such that the number of moles of the functional group of the curing agent is approximately equal to the number of moles of the epoxy group of the glycidyl ether of the novolac type phenolic resin containing the rope. The amount, filler is the whole,
The amount of filler to the bond is close to close packing,
The curing accelerator is used in a catalytic amount, and the internal mold release agent is used in an amount of about 02 to 2.0% by weight based on the total amount of the ingredients. In the case of this application, the curing agent is preferably a novolak-type phenol such as phenol novolak or In-cresol novolak, or the bromine-containing novola 1. The glycidyl ether of the polyhydric phenol resin can also be used in combination with the glycidyl ether of other polyhydric phenols.

Further, the composition containing the glycidyl ether and curing agent of the present invention can be molded into a glass cloth or polyester resin. In addition, the composition is useful in fields where heat resistance, flame retardance, and low hydrolyzable bromine content are desired, such as powder coatings for electrical insulation.

The present invention will be explained below using actual examples, but the present invention is not limited to actual examples.

Incidentally, the epoxy equivalent as used in the present invention is defined as Durham equivalent per mole of glycidyl ether group.

Hydrolyzable chlorine is a bromine-containing novolac type phenolic resin, glycidyl erthyl, dissolved in dioxane, an alcoholic solution of potassium hydroxide added, and heated under reflux for 30 minutes. It is defined by the weight fraction relative to the chlorine atoms in the glycidyl ether. The term "hydrolyzable bromine" is defined as the weight fraction of bromine atoms in the glycidyl ether obtained by replacing chlorine ions with bromine ions in a constant air flow in the same manner as described above.

Example 1 (1) Synthesis of bromine-containing novolac-type phenolic resin Attach temperature control, cooling pipe, dropping funnel, and stirrer.
00 was added to a Cherasco, 0.5 mol of 2.4 dibromophenol and 0.2 mol of sodium hydroxide as a basic catalyst were mixed at 80°C. followed by 3796
An aqueous formalin solution (containing 0.65 mol of formaldehyde) was added dropwise over 1 hour, and the mixture was kept warm for 3 hours.

Next, the reaction solution was neutralized with hydrochloric acid and orthocresol was reduced to 1.2
5 mol was added.

Furthermore, 0.085 mol of hydrochloric acid was added as an acidic catalyst.
Mixed at 0°C. Subsequently, a 37% aqueous formalin solution (containing 0.68 mol of formaldehyde) was added dropwise over 1 hour, and the mixture was kept warm for 8 hours.

Finally, the reaction solution was neutralized with a 5% aqueous NaOH solution, separated water was removed, and remaining water and unreacted substances were removed by distillation. The softening point of the reddish brown resin obtained at this time was 1
It was 00°C. The softening point was measured according to JIS-2581 (Petroleum asphalt softening point test method (ring and ball method)).

(2) Synthesis of glycidyl ether of bromine-containing novolac-type phenolic resin Using a thermometer, separation tube, dropping funnel, and hawk stirrer, use the bromine-containing phenol resin obtained in (1). 1.0 mol of novolak type phenolic resin (as phenolic hydroxyl group) was dissolved in 7.0 mol of epichlorohydrin, and a 48% aqueous sodium hydroxide solution (1.0 mol as sodium hydroxide) was added dropwise over 6 hours. This amount of epichlorohydrin and water were azeotropically distilled under reduced pressure (250 to 1 (g) at a temperature of 72°C and cooled in a separation tube. The epichlorohydrin layer was returned to the reaction system, and the water layer was removed from the system. After completion, epichlorohydrin was removed by distillation, and the reaction product was dissolved in toluene.Next, after P was removed from the by-product salt, toluene was removed by distillation to obtain glycidyl ether of a bromine-containing novolac type phenol resin.The glycidyl The epoxy equivalent of the ether is 245, and the hydrolyzable chlorine is 0.
．． 0.05%, hydrolyzable bromine 0.01%, softening point 74
°C 1119A (Determination of the bromine content of epoxy resins by X-green emission spectroscopy).

Examples 2 to 5 and Comparative Examples 1 to 2 (1) Synthesis of bromine-containing novolac type phenolic resin Bromine was synthesized in the same manner as in Example 1, except that the amounts and types of raw materials and catalysts shown in Table 1 were used. A novolak-type phenolic resin containing the resin was obtained.

(2) Synthesis of glycidyl ether of bromine-containing novolak phenol resin Glycidyl ether of phenol resin was obtained in the same manner as in Example 1, except that the bromine-containing novolak phenol resin obtained in (1) was used. . However, in Example 2, dioxane was added at a ratio of 80 parts by weight to 100 parts by weight of epichlorohydrin during glycidyl ether synthesis.

Reference Examples 1 to 3 - The glycidyl ether of the bromine-containing novolac type phenolic resin of Examples 1 and 4 and the glycidyl ether of the brominated phenol novolak (manufactured by Nippon Joyaku) were used.13B , E N is Br as shown in Figure 2.
Replaced. It has a methylene chain, and the Ilr content is 84-fold claw-shaped.

Using each of the above-mentioned glycidyl ethers as a base resin, phenol novolac was added as a curing agent so that the glycidyl ether group and phenolic hydroxyl group were equimolar. 2-phenyl-4-methylimidazole was added to the overlapping portion and mixed and frozen. This formulation was applied at 70 kg/af
, press molded at 160°C for 10 minutes, and then
The molded product was post-cured at 80° C. for 3 hours.

The dynamic viscoelasticity of this molded article was measured, and the peak of the main dispersion was taken as the glass transition temperature. This glass transition temperature was defined as heat resistance scale 1.Furthermore, a combustion test was carried out on the molded product in accordance with JIS-6911.Furthermore, regarding the impurity ion n degree, the glycidyl of the polyhydric phenol mentioned above The lO heavy part of ether was added to the pure water of the ioo heavy part, and the container was heated to 160°C with the container sealed (the water vapor pressure inside the container was approximately 5 atm), and held for 20 hours. At this time, impurity ions extracted into the water were measured using an ion chromatograph17, and the impurity ion concentration was converted into resin. The results of these measurements are shown in Table 2.

Table 2 From Table 2, it can be seen that the glycidyl ether of the present invention is a semiconductor! (It is luxurious and excellent in terms of physical properties required as a sealing material for a single-product circuit.Incidentally, the glass transition temperature required for this material is about 180°C or higher.In particular, bromine Regarding ion concentration, the value measured by water extraction at high temperature is more important than the measured value of hydrolyzable bromine.In other words, in the reliability test of semiconductor integrated circuits, as an accelerated test method, NNN13 stopped integrated The reliability of the sealing material is determined by the time it takes for a circuit to be kept in such high temperature and high humidity conditions until a defective product occurs due to corrosion of the aluminum wiring, etc., and the rate of defective products.

Therefore, the material that generates more impurity ions under high temperature and high humidity conditions is unsuitable as a sealing material, and becomes a fatal defect in the sealing material. As shown in Table 2, 1311EN" has a particularly large amount of bromide ion generation, which is a fatal defect as a sealing material. This is because the BEN [phase] bonds to carbon other than the benzene ring. This arises from a defect in its molecular structure, which is that it contains bromine.

Reference Examples 4 to 8 The glycidyl ethers of polyhydric phenols shown in Table 8 were used and evaluated in the same manner as in Reference Examples 1 to 3. The results are shown in Table 8.

As shown in Reference Example 6, the effect of the present invention is also recognized by using the glycidyl ether of the bromine-containing novolac type phenol resin of the present invention as a flame retardant imparting agent.

As shown in Reference Example 7, when a glycidyl ether with a low bromine content of 2 wt% was used, a high glass transition temperature was obtained, but sufficient flame resistance was not obtained. Further, as shown in Reference Example 8, when glycidyl ether with a high bromine content of 45 wt% was used, the glass transition temperature was lowered.

However, as shown in Reference Example 3, BREN■ has a bromine content of 84wt96 and Br ions also elute 86-, whereas the glycidyl ether of Reference Example 1O, which has a groove according to the present invention, has a chill structure. This shows that the above characteristics can significantly reduce impurities and ions.

Table 3 (1) 80 parts by weight of the glycidyl ether of Example 4 was melted and melted to the claw part of Sumiepoxy EFION-195XL70 to obtain Ri-W-A glycidyl ether.

[Brief explanation of the drawing]

Figure 1 shows the '0-NMI of the glycidyl ether of the bromine-containing novolak phenol resin obtained in Example 1.
The spectrum of I is shown. Unfortunately, Figure 2 does not show the 18C-NMR spectrum of Bren. In BILEN■ in Figure 2, the peak due to brominated methylene chains is 6%, '1'7. 'l-9μL ρ2//
Although this peak is observed in the culm m, this peak is not observed in the glycidyl ether of the present invention shown in FIG.

Claims (3)

[Claims] (1) Substantially all of the molecular chain terminals of general formula (1) are represented by general formula (1) (wherein R
2-Hiki is the same or different group selected from the group consisting of a hydrogen atom, an alkyl group having 1 to 10 carbon atoms, an aromatic group, and a halogen atom; (2) is the same or different group selected from the group consisting of a hydrogen atom and an alkyl group having 1 to 4 carbon atoms. ), a bromine-containing novolac-type phenolic resin glycidyl phenolic resin modified with a phenyl nucleus represented by the following formula, having a bromine content of 3 to 40% and a number average repeating unit number of 1 to 4o. (2) The glycidyl ether according to claim 1, which has a bromine content of 3 to 7%. (3) Substantially all of the molecular chain ends of the substantially linear polymer having repeating units represented by the general formula (1) (in the formula, 几1 to gourd are hydrogen atoms, carbon numbers 1 to Identical or (different) groups selected from the group consisting of 10 alkyl groups, aromatic groups and halogen atoms;
selected from the group consisting of alkyl groups, each of which is the same but different. ), the bromine content is 3 to 40% by weight, and the number average repeating unit number is 1 to 40. Sealant.