JPH08236905A - Overcoating material - Google Patents

Abstract

PURPOSE: To provide a flame retardant overcoating material with advantages in moisture resistance, heat resistance, chemical resistance, and electric characteristics, by using a given curable resin component. CONSTITUTION: An overcoating material is made up of reactive material (a) of polyphenylene ether and unsaturated carboxylic acid or its anhydride, triallyle isocyanurate and/or triallyle cyanurate (b), and curable polyphenylene ether resin compound (c) as indicated in a formula, where m and n are integers from 3 to 5, the sum of m and n is 8 or more, and z is alkyl group or bromoalkyl group with its carbon number of 4 or less. On the basis of 100 weight parts of the sum of (a) and (b), material (a) is 40 to 98 parts, and material (b) is 2 to 60 parts by weight. On the basis of 100 weight parts of the sum of (a), (b) and (c), materials (a) and (b) are 50 to 95 parts and material (c) is 5 to 50 parts by weight.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an overcoat material, and more specifically in the field of electronics industry,
The present invention relates to an overcoat material that imparts insulation, moisture resistance, and heat resistance in the fields of semiconductors, ICs, hybrid ICs, printed wiring boards, and the like.

[0002]

2. Description of the Related Art In recent years, there has been a remarkable trend toward miniaturization and high density of mounting methods in the field of electronic devices for communication, consumer use, industrial use, etc. Heat resistance, dimensional stability, electrical characteristics, and moldability are being demanded. For example, as the overcoat material, an epoxy resin, a polyimide resin, etc. have been conventionally known, but the epoxy resin has a problem in heat resistance and moisture resistance,
On the other hand, the polyimide resin has a drawback that it is excellent in heat resistance, but has a large hygroscopic property, resulting in deterioration of physical properties. As a new material for solving this problem, polyphenylene ether has been attracting attention in recent years and its application to electronic devices has been attempted.

Polyphenylene ether is an engineering plastic excellent in mechanical properties and electrical properties and has relatively high heat resistance. However, when it is intended to be used as an electronic device, extremely high solder heat resistance is required, and therefore the heat resistance inherent to polyphenylene ether is not sufficient at all. That is, the polyphenylene ether is deformed when exposed to a high temperature of 200 ° C. or higher, causing a significant decrease in mechanical strength and peeling of the copper foil formed on the resin surface for a circuit. Further, polyphenylene ether has strong resistance to acids, alkalis and hot water, but has extremely weak resistance to aromatic hydrocarbon compounds and halogen-substituted hydrocarbon compounds and is soluble in these solvents.

As one method for improving the heat resistance and chemical resistance of polyphenylene ether, a method has been proposed in which a crosslinkable functional group is introduced into the chain of polyphenylene ether and further cured to be used as a cured polyphenylene ether. There is. As a specific example, a polymer of 2-allyl-6-methylphenol or 2,6-diallylphenol is Journal of Polymer Scie.
No. 49, 267 (1961). U.S. Pat. Nos. 3,281,393 and 34
22062 discloses a copolymer of 2,6-dimethylphenol and 2-allyl-6-methylphenol or 2,6-diallylphenol. Also, US Pat. No. 4,634,742 discloses vinyl group-substituted polyphenylene ether. Furthermore, the present inventors previously developed a polyphenylene ether substituted with a propargyl group or an allyl group, a polyphenylene ether containing a triple bond or a double bond, and an unsaturated carboxylic acid- or acid anhydride-modified polyphenylene ether, and these have been developed. It was found that it was curable, and that the obtained cured product was insoluble in aromatic hydrocarbon solvents and halogen-substituted hydrocarbon solvents and had excellent dielectric properties (Japanese Patent Laid-Open No. 1-69628 and 1- No. 69629 publication,
No. 1-113425, No. 1-113426, No. 4-239017).

However, the polyphenylene ether itself is
It does not have sufficient flame retardancy for use in electrical parts.
Although it is practically strongly demanded to impart flame retardancy without impairing the excellent dielectric properties and heat resistance of polyphenylene ether, the addition of decabromodiphenyl ether analogs, which is an effective means, is environmentally friendly. From the viewpoint of protection, it is in the direction of restriction or prohibition.

[0006]

Under these circumstances, the present invention has good chemical resistance such as hygroscopicity, heat resistance, acid resistance, and alkali resistance, and excellent electrical properties such as insulation and dielectric constant.
Moreover, it is intended to provide an overcoat material excellent in flame retardancy.

[0007]

As a result of intensive studies, the present inventors have found that the curable resin composition of the present invention is very useful as an overcoat material, and completed the present invention. It was That is, the present invention provides (a) a reaction product of polyphenylene ether and an unsaturated carboxylic acid or an acid anhydride, (b) triallyl isocyanurate and / or triallyl cyanurate, and (c) the following general formula (1) ] The curable polyphenylene ether resin composition which consists of a compound represented by these, Comprising: The component (a) is 98-40 based on 100 weight part of the sum of (a) component and (b) component.
Parts by weight, 2 to 60 parts by weight of the component (b), and 95 to 50 parts by weight of the component (a) + (b) based on 100 parts by weight of the sum of the components (a) to (c); ) An overcoat material comprising a curable polyphenylene ether resin composition in which the component is 5 to 50 parts by weight.

[0008]

Embedded image [In the formula, m and n are integers of 3 to 5 and m + n is 8 or more,
Z is an alkyl group having 4 or less carbon atoms or a bromine-substituted alkyl group. The present invention will be described in detail below.

The polyphenylene ether used in the present invention is represented by the following general formula (2).

Embedded image [In the formula, m is an integer of 1 to 6, J is a polyphenylene ether chain substantially composed of a unit represented by the following formula (A),

[0010]

[Chemical 4] (Here, R _{1 to} R ₄ each independently represent a lower alkyl group, an aryl group, a haloalkyl group, a halogen atom, or a hydrogen atom.) Q represents a hydrogen atom when m is 1, and when m is 2 or more, It represents a residue of a polyfunctional phenol compound having 2 to 6 phenolic hydroxyl groups in one molecule and having a polymerization inactive substituent at the ortho and para positions of the phenolic hydroxyl group. ]

Examples of the lower alkyl group represented by R _{1 to} R ₄ in the general formula (A) include methyl group, ethyl group, n-propyl group, isopropyl group, n-butyl group and isobutyl group. A phenyl group etc. are mentioned as an example of an aryl group. Examples of the haloalkyl group include a bromomethyl group and a chloromethyl group. Examples of halogen atoms include bromine and chlorine.

As a typical example of Q in the general formula (2),
The compound group represented by the following four kinds of general formulas may be mentioned.

Embedded image

(Wherein A ₁ and A ₂ represent the same or different linear alkyl groups having 1 to 4 carbon atoms, X represents an aliphatic hydrocarbon residue and a substituted derivative thereof, an aralkyl group and a substituted thereof) Represents a derivative, oxygen, sulfur, a sulfonyl group, a carbonyl group, Y represents an aliphatic hydrocarbon residue and a substituted derivative thereof, an aromatic hydrocarbon residue and a substituted derivative thereof, an aralkyl group and a substituted derivative thereof, Z is oxygen, sulfur, sulfonyl group, a carbonyl group, two phenyl groups attached directly a _2, a ₂ and Y,
All the bonding positions of A ₂ and Z represent the ortho position and the para position of the phenolic hydroxyl group, r is 0 to 4, and s is an integer of 2 to 6. ) Specific examples include the following structural formula units and the like.

[0014]

[Chemical 6]

[0015]

[Chemical 7] The polyphenylene ether chain represented by J in the general formula (2) contains a unit represented by the following general formula (B) in addition to the unit represented by the general formula (A). Good.

[0016]

Embedded image [In the formula, R _{5 to} R ₉ each independently represent a hydrogen atom, a halogen atom, a lower alkyl group, an aryl group or a haloalkyl group, and R ₁₀ and R ₁₁ are not hydrogen at the same time. ]

As an example of the unit of the general formula (B),

[Chemical 9] Etc.

Preferred examples of the polyphenylene ether resin of the general formula (B) used in the present invention include poly (2,6) obtained by homopolymerization of 2,6-dimethylphenol.
-Dimethyl-1,4-phenylene ether), styrene graft polymer of poly (2,6-dimethyl-1,4-phenylene ether), copolymer of 2,6-dimethylphenol and 2,3,6-trimethylphenol, 2,
Copolymer of 6-dimethylphenol and 2-methyl-6-phenylphenol, 2,6-dimethylphenol and polyfunctional phenol compound: compound represented by the following general formula (3)

[0019]

[Chemical 10] (In the formula, m is an integer of 1 to 6, Q represents a hydrogen atom when m is 1, and when m is 2 or more, it has 2 to 6 phenolic hydroxyl groups in one molecule. Represents a residue of a polyfunctional phenol compound having a polymerization-inert substituent at the ortho- and para-positions of 1.), and the polyfunctional polyphenylene ether resin obtained by polymerization in the presence of, for example, JP-A-63- No. 301222, Japanese Patent Laid-Open No. 1-2974
Examples thereof include copolymers containing the units of the general formulas (A) and (B) as disclosed in JP-A-28.

Regarding the molecular weight of the polyphenylene ether resin described above, the viscosity number ηsp / c measured at 30 ° C. in a chloroform solution of 0.5 g / dl is 0.1 to 1.0.
Those in the range can be used satisfactorily.

The component (a) used in the present invention is a polymerizable compound derived from substantially an acid or an acid anhydride, which is produced by reacting the polyphenylene ether resin with an unsaturated carboxylic acid or an acid anhydride. Is a reaction product containing no double bond. The reaction product is probably a mixture of various products having various chemical structures, and the chemical structures thereof are not all elucidated. H. Glans, M .; K. Ak
capeddi, Macromolecules, vo
The following chemical structures described in 1991, 24, 383 to 386 are given as examples.

[0022]

[Chemical 11]

Examples of suitable acids and acid anhydrides include acrylic acid, methacrylic acid, maleic anhydride, fumaric acid,
Examples thereof include itaconic acid, itaconic anhydride, glutaconic anhydride, citraconic anhydride and the like. Particularly, maleic anhydride and fumaric acid are most preferably used. The reaction was carried out by mixing the polyphenylene ether resin with an unsaturated carboxylic acid or acid anhydride 10 times.
It is performed by heating in the temperature range of 0 ° C to 390 ° C. At this time, a radical initiator may coexist. Although both a solution method and a melt mixing method can be used as the reaction method, the melt mixing method using an extruder or the like can be carried out more easily and is suitable for the purpose of the present invention. The ratio of the unsaturated carboxylic acid or the acid anhydride is 0.01 to 5.0 parts by weight with respect to 100 parts by weight of the polyphenylene ether resin,
It is preferably 0.1 to 3.0 parts by weight. The triallyl isocyanurate and / or triallyl cyanurate used as the component (b) of the present invention is a trifunctional monomer represented by the following structural formula.

[0024]

[Chemical 12]

In carrying out the present invention, triallyl isocyanurate and triallyl cyanurate can be used not only individually but also as a mixture of both at an arbitrary ratio. In the present invention,
Triallyl isocyanurate and triallyl cyanurate act as a plasticizer and a crosslinking agent. That is, it improves the flow of resin during pressing and the crosslink density.

The flame retardant used as the component (c) of the present invention is represented by the structural formula of the above general formula (1). m and n are each an integer of 3 to 5, m + n is 8 or more, and Z is an alkyl group having 4 or less carbon atoms or a bromine-substituted alkyl group.
From the viewpoint of the flame retardant effect, m + n is preferably 9 or more and 10
Is most preferred. Z may have any number of hydrogens replaced by bromine. The number of carbons may be 4 or less, -C
H ₂ CH ₂ - is most preferred.

Of the three components (a) to (c) described above, the blending ratio of the component (a) and the component (b) is 10 in total.
98 to 40 parts by weight of the component (a) based on 0 parts by weight,
The component (b) is 2 to 60 parts by weight, more preferably the component (a) is 95 to 50 parts by weight, and the component (b) is 5 to 50 parts by weight.
The range is parts by weight. When the amount of the component (b) is 2 parts by weight or less, the chemical resistance is insufficiently improved, which is not preferable, and when it exceeds 60 parts by weight, the dielectric properties, flame retardancy and moisture absorption properties are deteriorated.
Further, it is not preferable because it becomes a very brittle material after curing.

The mixing ratio of the component (c) is from (a) to
(A) + based on 100 parts by weight of the sum of components (c)
Component (b) is 95-50 parts by weight, component (c) is 5-50.
The range is parts by weight. Component (C) is preferably 10 to 4
The amount is 0 parts by weight, more preferably 10 to 30 parts by weight. When the amount of the component (c) is less than 5 parts by weight, it is difficult to obtain sufficient flame retardancy, and when it exceeds 50 parts by weight, the fluidity of the resin may be reduced or the adhesive strength may be reduced.

The curable resin composition of the present invention can be made into a composite material by adding a base material in order to enhance mechanical strength and dimensional stability. As the substrate used in the present invention, various glass cloths such as roving cloth, cloth, chopped mat, surfacing mat, asbestos cloth, metal fiber cloth and other synthetic or natural inorganic fiber cloth; polyvinyl alcohol fiber, polyester fiber, Woven or non-woven fabric obtained from synthetic fibers such as acrylic fiber, wholly aromatic polyamide fiber, polytetrafluoroethylene fiber; natural fiber cloth such as cotton cloth, linen cloth, felt; carbon fiber cloth; kraft paper, cotton paper, paper-glass blend Natural cellulose-based papers such as fine paper are used alone or in combination of two or more kinds.

The ratio of the base material in the curable composite material is 5 based on 100 parts by weight of the curable composite material.
˜90% by weight, more preferably 10 to 80% by weight, still more preferably 20 to 70% by weight. If the amount of the base material is less than 5% by weight, the dimensional stability and strength of the composite material after curing will be insufficient, and if the amount of the base material is more than 90% by weight, the dielectric properties and flame retardancy of the composite material will be inferior.

As the method for mixing the components (a) to (c) of the present invention, a solution mixing method in which the respective components are uniformly dissolved or dispersed in a solvent, or a melt blending method in which the components are heated and melted by an extruder or the like. Etc. are available. As the solvent used for the solution mixing, a halogen-based solvent such as dichloromethane, chloroform and trichloroethylene; an aromatic solvent such as benzene, toluene and xylene; a ketone solvent such as acetone, methyl ethyl ketone and methyl isobutyl ketone; tetrahydrofuran alone or Used in combination of two or more.

The resin composition of the present invention may be molded in advance according to its use and then cured, and the molding method is not particularly limited. Usually, a casting method in which the resin composition is dissolved in the above-mentioned solvent and molded into a desired shape, or a heating and melting method in which the resin composition is heated and melted and molded into a desired shape is used.

The above-mentioned casting method and heat melting method may be carried out independently. Moreover, you may carry out combining each. For example, it is possible to obtain a sheet of the present resin composition by laminating several to several tens of films of the present resin composition prepared by a casting method and heating and melting the film by a heating and melting method, for example, using a press molding machine.

If desired, a coupling agent may be used in the above composite material for the purpose of improving the adhesiveness at the interface between the resin and the substrate. As the coupling agent,
General silane coupling agents, titanate coupling agents, aluminum-based coupling agents, zircoaluminate coupling agents and the like can be used.

As will be described later, the resin composition of the present invention undergoes a crosslinking reaction by means of heating or the like to be cured, but it is radical-initiated for the purpose of lowering the reaction temperature or promoting the crosslinking reaction of unsaturated groups. You may use it, including an agent. The amount of radical initiator used in the resin composition of the present invention,
0.1-10 based on the sum of the components (a) and (b)
% By weight, preferably 0.1 to 8% by weight.

Typical examples of the radical initiator will be given below.
Benzoyl peroxide, cumene hydroperoxide, 2,5-dimethylhexane-2,5-dihydroperoxide, 2,5-dimethyl-2,5-di (t-
Butyl peroxy) hexyne-3, di-t-butyl peroxide, t-butyl cumyl peroxide, α,
α'-bis (t-butylperoxy-m-isopropyl) benzene, 2,5-dimethyl-2,5-di (t-butylperoxy) hexane, dicumyl peroxide,
Di-t-butylperoxyisophthalate, t-butylperoxybenzoate, 2,2-bis (t-butylperoxy) butane, 2,2-bis (t-butylperoxy) octane, 2,5-dimethyl There are peroxides such as, but not limited to, 2,2,5-di (benzoylperoxy) hexane, di (trimethylsilyl) peroxide, and trimethylsilyltriphenylsilylperoxide. Also, although not a peroxide, 2,3-dimethyl-2,
3-diphenylbutane can also be used as a radical initiator. However, the initiator used for curing the resin composition is not limited to these examples.

The resin composition of the present invention can be used by blending an amount of a filler or an additive in a range that does not impair the original properties for the purpose of imparting desired performance depending on the application. The filler may be fibrous or powdery.
As additives, antioxidants, heat stabilizers, antistatic agents,
Examples include plasticizers, pigments, dyes, colorants and the like. The chlorine in order to further improve the flame retardancy, bromine, and flame retardant _{phosphorus-based, Sb 2 O 3, Sb 2} O 5, NbSbO 3 · 1
A flame retardant aid such as / 4H ₂ O can also be used in combination. In the composite material including the base material, a combination of brominated diphenylethanes and antimony oxide is preferably used. Furthermore,
It is also possible to blend other thermoplastic resins, or one or more thermosetting resins.

[0038]

EXAMPLES The present invention will be described below with reference to examples in order to further clarify the present invention, but the scope of the present invention is not limited to these examples. Moreover, the obtained printed wiring board was evaluated by the following methods.・ Long-term reliability The printed wiring board is 1000 at 60 ℃ and 95% relative humidity.
After left for a period of time, the product was taken out, abnormalities in appearance such as swelling, and corrosion were visually evaluated. -Flame retardancy A flame retardancy test corresponding to UL-94 standard was conducted.

Reference Example 1 Viscosity number ηsp / c of 0.5 measured at 30 ° C. in a 0.5 g / dl chloroform solution.
100 parts by weight of poly (2,6-dimethyl-1,4-phenylene ether) of 4 and 1.5 parts by weight of maleic anhydride,
And 2,5-dimethyl-2,5-di (t-butylperoxy) hexane [Perhexa 25 manufactured by NOF CORPORATION]
B] 1.0 part by weight was dry-blended at room temperature and then extruded by a twin-screw extruder under the conditions of a cylinder temperature of 300 ° C. and a screw rotation speed of 230 rpm. This reaction product is referred to as A
And

Reference Example 2 100 parts by weight of poly (2,6-dimethyl-1,4-phenylene ether) having a viscosity number ηsp / c of 0.40 measured by the same method as in Reference Example 1,
After dry blending 1.5 parts by weight of maleic anhydride at room temperature, the cylinder temperature was 300 ° C. and the screw rotation speed was 23.
It was extruded by a twin-screw extruder under the condition of 0 rpm. This reaction product is designated as B.

(Examples 1 and 2) A curable polyphenylene ether resin composition having the composition shown in Table 1 was dissolved in chloroform. This solution was applied to a printed wiring board, dried, and then subjected to a curing reaction at 200 ° C. for 30 minutes to overcoat the surface of the printed wiring board. When this overcoated printed wiring board was left for 1000 hours under the conditions of 60 ° C. and 95% humidity, no abnormalities in appearance such as swelling and corrosion were found.

(Comparative Examples 1 and 2) The printed wiring board surface was overcoated under the same conditions as in Examples 1 and 2 except that the overcoat material shown in Table 1 was used instead of the overcoat material of the present invention. Those not using the overcoat material of the present invention were inferior in long-term reliability. 60 ° C, 95% R
After being left for H and 1000 hours, the appearance was swollen and corrosion was observed.

COMPARATIVE EXAMPLE 3 An unmodified polyphenylene ether was used in place of the overcoat material of the present invention.
When an overcoat material was prepared with the resin composition shown in, flame retardancy was remarkably reduced.

[0044]

[Table 1]

[0045]

The overcoat material of the present invention has a hygroscopic property,
Not only is it excellent in heat resistance, but it is also sufficiently excellent in chemical resistance to acid-alkali and halogen-based solvents. It is also excellent in electrical properties such as dielectric constant and insulation. Furthermore, since no decabromodiphenyl ether analogue is used as a flame retardant, it is an excellent material from the viewpoint of environmental protection. Therefore, it can be suitably used as an overcoat material for semiconductor elements, printed wiring boards and the like.

Claims (1)

[Claims] 1. A reaction product of (a) a polyphenylene ether and an unsaturated carboxylic acid or an acid anhydride, (b) a triallyl isocyanurate and / or a triallyl cyanurate, and (c) the following general formula (1). A curable polyphenylene ether resin composition comprising a compound represented by the following formula, wherein the component (a) is 98 to 40 parts by weight, and the component (b) is based on 100 parts by weight of the sum of the components (a) and (b). Is 2 to 60 parts by weight, and (a) + (b) components are 95 to 100 parts by weight based on the sum of the components (a) to (c).
An overcoat material comprising a curable polyphenylene ether resin composition having 50 parts by weight and 5 to 50 parts by weight of the component (c). Embedded image [In the formula, m and n are integers of 3 to 5 and m + n is 8 or more,
Z is an alkyl group having 4 or less carbon atoms or a bromine-substituted alkyl group. ]