KR940001718B1 - Dendritic Formulations Containing Polyepoxide and Polyphenylene Ether-Polyepoxide Compositions Useful for Manufacturing Printed Circuit Boards - Google Patents

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Description

Dendritic formulations containing polyepoxide and polyphenylene ether-polyepoxide compositions useful for printed circuit board manufacture

The present invention relates to dendritic compositions useful as dielectrics, in particular polyphenylene ether-polyepoxide compositions suitable for producing printed circuit boards.

Many polyphenylene ether-polyepoxide compositions are known that have desirable dielectric properties and are probably useful for the manufacture of circuit boards. However, many of these have not been widely used commercially due to one or more drawbacks of their properties. Polyphenylene ether is therefore an excellent dielectric and in this respect the properties of mixtures with polyepoxides are desirable, but lack the solvent resistance required to withstand washing with solvents such as methylene chloride in the circuit board. Other drawbacks are found in areas such as flammability, solderability and high temperature resistance. In addition, the time required to cure such a composition is typically too long to manufacture circuit boards in bulk and efficiently.

In addition to excellent dielectric properties, dendritic compositions used in printed circuit board manufacture must be highly flame retardant. Underwriters Laboratories Test Method The V-1 rating as measured by UL-94 is widely required along with the required V-0. The V-0 rating requires a flame-out time (FOT) of 10 seconds or less and a cumulative FOT of 50 seconds or less for five samples for any implementation. As a practical matter, buyers often require a maximum cumulative FOT of 35 seconds.

The plate produced should be substantially free of weight loss and its surface should not be damaged enough to be noticeable by contact with methylene chloride. When exposed to liquid solder at 288 ° C., solderability should be good, as evidenced by the minimum rate of plate thickness increase (Z-axis expansion) as possible. In addition to all these properties of the cured material, relatively short cure times are highly desirable.

Pending co-owned US Patent Application No. 92,725 (filed September 3, 1987) is optionally used as a curing accelerator for zinc salts or aluminum salts of diketones such as acetylacetone in the presence of phenolic compounds or basic nitrogen compounds. Polyphenylene ether-polyepoxide compositions that are curable by way of state are described. While these compositions are excellent in dielectricity, solder resistance and solvent resistance, there is room for improved flame retardancy and curing time.

Japanese Patent Application Laid-Open No. 58/69052 describes mixtures of polyphenylene ethers with various types of polyepoxides. The latter include epoxy novolak resins and polyglycidyl ethers of compounds such as bisphenol A and 3,5,3 ', 5'-tetrabromobisphenol A. Curing of these compounds is accomplished by contact with various known curing agents, including amines. However, it has been found that the cured compositions lack solvent resistance and in certain cases solderability.

The present invention provides a series of dendritic compositions containing polyepoxides and mixtures thereof with polyphenylene ethers. The latter provides a workable prepreg when used to impregnate suitable fibrous reinforcing materials such as fiberglass cloth. Such compositions readily dissolve in organic solvents that promote impregnation. These can also be mixed with other components to quickly form curable materials with high solder resistance, solvent resistance and flame retardancy, and excellent dielectric and high temperature dimensional stability. The cured material is therefore excellent when used as a laminate for printed circuit boards.

In one aspect of the invention, the invention contains 15 to 20% chemically bound bromine; (A) one or more halogen-free bisphenol polyglycidyl ethers having an average of one or less aliphatic hydroxy groups per molecule; (B) a mixture containing about 15-25% of at least one halogen-free epoxidized novolac and (C) at least 25-35% of at least one bisphenol containing bromine as an aryl substituent, wherein all percentages are components ( Based on the total weight of A), (B) and (C)] in a dendritic composition containing the reaction product obtained by heating in the presence of at least one basic component catalytic amount.

Component (A) in the compositions of the present invention is at least one halogen-free bisphenol polyglycidyl ether. The most common compounds of this type are prepared by reacting bisphenol with epichlorohydrin (as used herein, the term "bisphenol" refers to a compound containing two hydroxyphenol groups bound to aliphatic or cycloaliphatic residues). And they may also contain aromatic substituents). The said compound can be represented by the following general formula (I).

Wherein n has an average of 1 or less; A ¹ and A ² are each monocyclic divalent aromatic radicals; Y is a bridging radical that separates A ¹ from one or two valence A ² .

In general formula (I), OA ¹ and A ² —O bonds are typically present in the meta or para position of A ¹ and A ² with respect to Y.

In formula (I), the A ¹ and A ² values may be unsubstituted phenylene or substituted derivatives thereof, and examples of the substituents (one or more) are alkyl, nitro and alkoxy and the like. Unsubstituted phenylene radicals are preferred. A ¹ and A ² may each be, for example, o- or m-phenylene and the remainder may be p-phenylene, but both are preferably p-phenylene.

The bridge radical Y is one or two, preferably one atoms separating A ¹ from A ² . This is most often the hydrocarbon radical, in particular methylene, cyclohexylmethylene, ethylene, isopropylidene, neopentylidene, cyclohexylidene or cyclopentadedecidene, in particular gem-alkylene (alkylidene) radicals, most preferred Preferably a saturated radical such as isopropylidene. However, it also includes radicals containing atoms other than carbon and hydrogen such as carbonyl, oxy, thio, sulfoxy and sulfone.

Commercially available epichlorohydrin as component (A), including EPON 825 (n = 0) and EPON 828 (n = about 0.14), available from Shell Chemical Co., and 2,2- Reaction product with bis (4-hydroxyphenyl) propane (bisphenol A).

Component (B) is one or more halogen-free epoxidized novolacs. Suitable novolacs for use as precursors thereof are known in the art and are typically prepared by reacting formaldehyde with a hydroxy aromatic compound such as phenol (often preferred), cresol or tert-butylphenol. Thereafter, the novolac is reacted with an epoxy component such as epichlorohydrin to prepare a resin useful as component (B).

Various epoxidized novolacs are commercially available and any of these can be used in accordance with the present invention. Usually, it is highly desirable that the epoxidized novolac be substantially free of free phenolic hydrogen atoms.

Component (C) is a brominated derivative of at least one bisphenol, generally bisphenol A, containing bromine in substituent form in the aromatic ring. The object according to the invention is in principle to provide flame retardancy. 2,2-bis (3,5-dibromo-4-hydroxyphenyl) propane is preferred as component (C) because of its availability, relatively low cost and special suitability for the purposes of the present invention.

As noted above, component (B) and component (C) make up about 15-25% and 25-35% of the composition of the present invention, respectively, and component (A) is the remaining amount. Lower concentrations of component (B) or component (C) lead to unacceptable decreases in solvent resistance and / or flame resistance. Increasing component (C) may result in incompatible materials. The preferred proportion of component (C) is in the range of 28 to 32%.

According to the invention, the mixture containing components (A), (B) and (C) is most frequently in the presence of at least one basic component catalytic amount, most often from about 125 to 225 ° C, preferably from about 150 to 200 ° C, most Preferably at about 160 to 190 ° C. Such mixtures preferably consist essentially of the above components; In other words, these components are those that affect novel and essential properties.

Triarylphosphines, especially triphenylphosphines, are preferred components because of their low tendency to cause side reactions and damages at low concentrations when they remain present after the reaction is completed. The proportion of catalyst is typically about 0.1 to 0.5% by weight. The reaction is preferably carried out in an inert atmosphere such as nitrogen, especially when triarylphosphine is used as catalyst. Inert organic solvents having a boiling point of about 125 [deg.] C. or less, typically aromatic hydrocarbons such as toluene, can be used, but the solvents generally have no advantage in this respect.

The structure of the dendritic composition thus obtained is not completely known. Brominated moieties have been found to be "upstaged" (ie, partially cured) compositions derived from compounds of general formula (I) forming part of the molecular structure. Epoxidized novolacs can also be chemically bound to molecules of various proportions of upstage composition.

Illustrated by the following examples of upstage compositions of the invention.

Example 1

50 parts by weight of bisphenol A diglycidyl ether, 30 parts by weight of 2,2-bis (3,5-dibromo-4-hydroxyphenyl) propane, grading from Ciba-Geigy "EPN A mixture of 20 parts by weight of epoxy novolac resin and 0.2 parts by weight of triphenylphosphine, sold as 1138 ", is heated at 165 ° C. for 1 hour with stirring in nitrogen atmosphere. The product is the desired upstage composition and contains 17.6% bromine.

In order to prepare compositions useful for making printed circuit boards with the desired properties, the upstageized compositions of the invention are mixed with polyphenylene ethers. In particular, another aspect of the present invention contains 5 to 10% of chemically bound bromine; (I) a dendritic blend containing about 35-60% of the upstageted composition and (II) about 40-65% of one or more polyphenylene ethers, wherein percent (%) is based on the weight of the total resin component It is.

Polyphenylene ethers useful as component (II) in the blend of the invention contain many structural units of the general formula (II):

Wherein Q ¹ is each independently halogen, primary or secondary lower alkyl (ie, alkyl having up to 7 carbon atoms), phenyl, haloalkyl, aminoalkyl, hydrocarbonoxy, or at least two carbon atoms are halogen and oxygen Halohydrocarbonoxy to separate atoms; Q ² is each independently hydrogen, halogen, primary or secondary lower alkyl, phenyl, haloalkyl, hydrocarbonoxy or halohydrocarbonoxy as defined for Q ¹ . Examples of suitable primary lower alkyl groups are methyl, ethyl, n-propyl, n-butyl, isobutyl, n-amyl, isoamyl, 2-methylbutyl n-hexyl, 2,3-dimethylbutyl, 2-, 3 Or 4-methylpentyl and the corresponding heptyl group. Examples of secondary lower alkyl groups are isopropyl, secondary-butyl and 3-pentyl. Preferably, the lower alkyl radical is also straight rather than branched. Most often, Q ¹ is each alkyl or phenyl, especially C _1-4 alkyl, and Q ² is each hydrogen. Suitable polyphenylene ethers are described in the majority of patent documents.

Both homopolymer and copolymer polyphenylene ethers are included. Suitable homopolymers are, for example, those containing 2,6-dimethyl-1,4-phenylene ether units. Suitable copolymers include (for example) random copolymers containing such units mixed with 2,3,6-trimethyl-1,4-phenylene ether units. Many suitable random copolymers and homopolymers are described in the patent literature.

Also included are polyphenylene ethers containing residues that modify properties such as molecular weight, melt viscosity and / or impact strength. Such polymers are described in the patent literature and may be used in a known manner to form hydroxy-free vinyl monomers such as acrylonitrile and vinylaromatics (such as styrene), or hydroxy-free polymers such as polystyrene and elastomers in a known manner. It can also be prepared by grafting with ene ether. The product typically contains both grafted or ungrafted residues. Other suitable polymers react with hydroxy groups and coupling agents in the two polyphenylene ether chains in a known manner to form a coupled poly, which produces a high molecular weight polymer containing the reaction product of the hydroxy groups with the coupling agent. Phenylene ether.

Examples of coupling agents are low molecular weight polycarbonates, quinones, heterocycles and formals.

For the purposes of the present invention, the number average molecular weight of the polyphenylene ether is about 3,000 to 40,000, preferably about 12,000 or more, most preferably about 15,000 or more, and the weight average molecular weight is about as determined by gel permeation chromatography. In the range of 20,000 to 80,000. Its intrinsic viscosity is most frequently 0.35 to 0.6 dl / g as measured in chloroform at 25 ° C.

Polyphenylene ethers are typically prepared by oxidatively coupling one or more corresponding monohydroxy aromatic compounds. A particularly useful and readily available monohydroxy aromatic compound is 2,5-xyleneol, wherein Q ¹ is each methyl and Q ² is each hydrogen, while the polymer is poly (2,6-dimethyl-1 , 4-phenylene ether) and 2,3,6-trimethylphenol, wherein each Q ¹ and one Q ² is methyl and the remaining Q ² is hydrogen.

Various catalyst systems are known for the production of polyphenylene ethers by oxidative coupling. There is no particular limitation as to the catalyst selection, and any of the known catalysts can be used. Most often they contain one or more heavy metal compounds, such as copper, manganese or cobalt compounds, usually in admixture with various other materials.

Preferred catalyst systems consist of the first type containing a copper compound. Such catalysts are described, for example, in US Pat. Nos. 3,306,874, 3,306,875, 3,914,266, and 4,028,341. These are usually mixtures of copper ions (II and III), halide (ie chloride, bromide or iodide) ions and one or more amines.

The catalyst system containing the manganese mixture constitutes a second preferred kind. These are usually alkaline systems in which divalent manganese is mixed with anions such as halides, alkoxides or phenoxides. Most often, manganese contains one or more complexing agents and / or dialkylamines, alkanolamines, alkylenediamines, O-hydroxy aromatic aldehydes, O-hydroxyazo compounds, ω-hydroxyoximes (monomers and polymers). Sex), as a complex with chelating agents such as O-hydroxyaryl oxime and β-diketone. Also known are cobalt-containing catalyst systems. Manganese and cobalt-containing catalyst systems suitable for the production of polyphenylene ethers are known in the art because they are described in numerous patent documents and patent publications.

Particularly useful polyphenylene ethers for the purposes of the present invention are those containing molecules having at least one of the terminal groups of the general formulas (III) and (IV):

Wherein Q ¹ and Q ² are as defined above; Each R ¹ is independently hydrogen or alkyl; Provided that the total number of carbon atoms of both R ¹ radicals is 6 or less; Each R ² is independently hydrogen or a C _1-6 alkyl radical.

Preferably each R ¹ is hydrogen and each R ² is alkyl, in particular methyl or n-butyl.

Polymers containing aminoalkyl substituted terminal groups of general formula (III) are obtained by incorporating a suitable primary or secondary monoamine as one of the components of the oxidative coupling reaction mixture, especially when using copper- or manganese-containing catalysts. You may. These amines, in particular dialkylamines, preferably di-n-butylamine and dimethylamine, are most often chemically used in polyphenylene ethers by replacing one of the α-hydrogen atoms on one or more Q ¹ radicals. Combined. The main reaction site is the radical of Q ¹ adjacent to the hydroxy group on the terminal unit of the polymer chain. During further treatment and / or mixing, the aminoalkyl substituted end groups have quinone metide intermediates of formula (V) having a number of beneficial effects, possibly including an increase in impact strength and other compounding ingredients ( various reactions, including quinone methide-type intermediate).

See US Pat. Nos. 4,054,553, 4,092,294, 4,477,649, 4,477,651 and 4,517,341, which are incorporated herein by reference.

Polymers having 4-hydroxybiphenyl end groups of general formula (IV) are typically obtained from reaction mixtures in which the diphenoquinone byproducts of general formula (VI) are present, in particular in a copper-halide secondary or tertiary amine system. do.

In this regard, US Pat. No. 4,477,629 again refers to US Pat. Nos. 4,234,706 and 4,482,697, which are also incorporated herein by reference. In mixtures of this type, diphenoquinones are immediately incorporated into substantial proportions of the polymer as mostly terminal groups.

In many polyphenylene ethers obtained under these conditions, a substantial proportion of the polymer molecules, typically constituting about 90% by weight of the polymer, has terminal groups having one or often both of Formulas (III) and (IV). It contains. However, it should be appreciated that other terminal groups may be present and, in the broadest sense, the present invention may not vary depending upon the molecular structure of the polyphenylene ether terminal groups.

From the above, it will be apparent to those skilled in the art that the polyphenylene ethers contemplated for use in the present invention include those which are all presently known, regardless of changes in structural units or auxiliary chemical properties.

In addition to polyphenylene ethers and upstage compositions, the resinous blends of the present invention are preferably up to about 10% of one or more of the polyepoxy compounds described above with reference to components (A) and (B). Component (III) is contained in an amount of. The polyepoxy compound acts to improve solvent resistance of the cured compositions below. Epoxides and novolacs (component (B)) are generally preferred because of their high solubility in the solvents usually used as follows. Dendritic formulations containing no component (III) are within the scope of the present invention, but are usually not preferred.

The dendritic blend of the present invention contains about 35 to 60% of component (I) and about 40 to 65% of component (II). If component (III) is present, it contains up to about 10%. All of these percentages are based on all dendritic components in the formulation. Preferred proportions are about 35 to 45% of component (I), about 50 to 60% of component (II) and about 4 to 8% of component (III). The formulation also contains, at least in part, 5 to 10%, preferably 6 to 9%, chemically bound bromine supplied by component (I). The percentages exclude any solvents that may be present.

An important use of the upstageized compositions and dendritic formulations of the present invention is in making cured dendritic laminates useful in printed circuit boards. For this purpose, the dendritic blends are mixed with various other materials during or after their preparation. Such other materials may include, for example, conventional catalysts and / or curing agents.

Dendritic formulations are particularly useful when dissolved in inert organic solvents, generally aromatic hydrocarbons such as toluene, and are used to impregnate glass woven fabrics that may be formed into prepregs. When cured, copper-clad laminates useful for manufacturing printed circuit boards characterized by excellent dielectric properties, solderability, flame retardancy, resistance to high temperature conditions and solvent resistance as described above using the prepreg laminate) can be formed.

Curable compositions of the kind described in pending co-owned US Patent Application No. [RD-18537] and claimed particularly useful for this purpose contain chemically bound bromine in an amount useful to impart flame retardancy; About 25-50% of component (I); About 35 to 55% of component (II); Preferably from about 4 to 15% of one or more halogen-free novolacs in which substantially all of the components (III) and (IV) are present in the form of phenolic hydroxy groups in amounts of up to about 10%; (V) one or more imidazole and arylene polyamines in an amount that provides at least 2 milliequivalents of basic nitrogen per 100 parts of said curable composition; (VI) about 0.1 to 1.0% zinc in the form of a zinc salt soluble or stably dispersible in the curable composition; (Iii) contains about 1 to 4% of antimony pentoxide which is stably dispersed in the curable composition; Wherein the curable composition is dissolved in an effective amount, typically solute concentration of about 30 to 60% in an inert organic solvent, all% by weight, and% of components (I) to (iii) present Based on ingredients, all other dendritic and brominated materials modes.

Component (IV) is one or more novolacs in which substantially all oxygen is present in the form of phenolic hydroxy groups.

Thus, the molecular structure is similar to the epoxidized novolac described above except that it is not epoxidized. Tert-butylphenol-formaldehyde novolac is often preferred.

Component (V) is at least one compound selected from the group consisting of imidazole and arylene polyamines.

Any of these imidazoles and polyamines are known to be useful as curing agents for epoxy resins in the art and may be used. Particularly useful imidazoles are imidazole, 1,2-dimethylimidazole, 2-methylimidazole, 2-heptadecylimidazole and 1- (2-cyanoethyl) -2-phenylimidazole. Commercially available imidazole-irylene polyamine mixtures are often preferred; Particularly preferred mixtures contain arylene polyamines having a large degree of alkyl substitution on the aromatic ring, typically having at least three substituents. Typically, diethylmethyl substituted m- and p-phenylenediamines are the most preferred polyamines.

The amount of component (V) is chosen to cure rapidly after solvent removal. This requires at least 2 millie equivalents, preferably at least 4.5 milliequivalents of basic nitrogen, including basic nitrogen present in the polyphenylene ether per 100 parts of the curable composition (mostly general formula (III) as a terminal group). Therefore, when using polyphenylene ether which is essentially free of basic nitrogen, the proportion of component (V) must be increased. (For the purposes of the present invention, the equivalent of imidazole is equal to its molecular weight and the equivalent of diamine is half its molecular weight).

Component (VI) is a chemically mixed zinc provided in the form of a zinc salt that is soluble or stably dispersible in the curable composition. Zinc salts of diketones, in particular zinc acetylacetonates and zinc salts of fatty acids, in particular zinc sterates, in which one carbon atom separates carbonyl groups, are a form of zinc suitable for this purpose. In general, fatty acid salts in which component (V) contains an alkylene polyamine are preferred, and diketone salts are preferred when component (V) is all imidazole.

Under certain conditions, zinc bis (acetylacetonate) can form hydrates, which easily lose acetylacetone, making it insoluble in the organic systems used to make laminates. It may therefore be necessary to carry out steps for maintaining zinc in a stable dispersion.

One way to do this is to continue stirring the composition; However, this is not usually done. A better way is to form alcoholates of zinc acetyl acetonate, such as by reacting with methanol. The alcoholate loses more alcohol than acetylacetone under similar conditions and will remain in solution or homogeneous suspension.

Another way to maximize homogeneity is to use zinc fatty acid salts. Yet another method is to use a titanium compound as admixture as described below.

Component is antimony pentoxide, which must also be maintained in a stable dispersion. This can be done by stirring and / or mixing with a suitable dispersant, many of which are known in the art.

One preferred dispersant is a polymer that is miscible with the dendritic component of the curable composition but is substantially nonreactive under the conditions used, and is typically polyester. If component (VI) is a fatty acid zinc salt, a stronger dispersant, such as an amine, may be required, since these salts may form an insoluble complex with antimony pentoxide separately.

Also preferably, the amount of component (III) present in the curable composition is about 4-15%.

In the curable composition, component (IV) acts as a curing agent and component (V) acts as a curing catalyst. Component (VI) has promoter properties and promotes curing; It also acts to improve the solvent resistance and flame resistance.

Component acts as a synergist to bromine to improve flame retardancy. If this is not present, the proportion of bromine compounds required to provide VO flame retardancy is much higher, typically about 12%, and the only way to address the incompatibility of bromine compounds is to use more expensive bromine sources. .

The broad proportions of bromine and components (I) to (iii) in the curable compositions have been described above. The most preferred ratio is as follows:

Bromine-6-9%;

Component (I) —about 30-40%;

Component (II)-about 40-50%;

Component (III)-about 4.2 to 4.8%;

Component (IV)-about 4 to 8%;

Component (V)-about 5-10 milliequivalents of basic nitrogen;

Component (VI)-zinc about 0.1-0.6%;

Ingredient (iii)-about 1 to 3% antimony pentoxide;

Other materials may also be present. These include inert particulate fillers such as talc, clay, mica, silica, alumina and calcium carbonate. In addition, the bromine content in the curable composition may be partially supplied by materials such as reaction products of bisphenol A with tetrabromobisphenol A and reactions of alkyl tetrabromophthalate and / or epichlorohydrin. Alkyl tetrabromophthalate also acts as a plasticizer and a flow improver. In addition, materials such as antioxidants, heat and ultraviolet stabilizers, lubricants, antistatic agents, dyes and pigments may also be present.

Materials that can be present in small amounts to improve solvent and miscibility of curable compositions are one or more aliphatic tris (dialkylphosphate) titanates. Suitable phosphate titanates are known in the art and are commercially available. These can be represented by the following general formula:

In which R ³ is C _2-6 primary or secondary alkyl or alkenyl, preferably alkenyl; R ⁴ is C _1-3 alkylene, preferably methylene; R ⁵ is C _1-5 primary or secondary alkyl; R ⁶ is C _5-12 primary or secondary alkyl; x is 0 to about 3, preferably 0 or 1.

Most preferably, R ³ is allyl, R ⁵ is ethyl, R ⁶ is octyl and x is 0. The phosphate titanate is most often present in an amount of about 0.1 to 1,0 parts by weight per 100 parts of the dendritic composition.

The curable compositions can be used as varnishes for impregnating fibrous substrates (woven or nonwoven), such as glass, quartz, polyester, polyamide, polypropylene, cellulose, nylon or acrylic fibers, preferably glass. . When the solvent is removed by evaporation, fibrous composite prepregs are obtained which may be cured by applying heat and pressure. As used herein, "prepreg" means a curable product that contains a substrate impregnated with an uncured or partially cured dendritic material.

Typically, 2 to 20 layers of prepreg laminates are compression molded at a pressure of about 20 to 60 kg / cm 2 at about 200 to 250 ° C. Laminates deposited by conductive metals, such as copper, useful for printed circuit board manufacture can be prepared and cured by methods known in the art. Thereafter, the metal deposit is patterned as conventionally.

The preparation of the compositions of the invention and curable compositions containing them are exemplified by the following examples. All parts and percentages are parts by weight and percentages unless otherwise indicated.

In Examples 2 to 9 the following components are used:

Component (I)-product of Example 1

Component (II) -poly (2,6-dimethyl-1,4-phenylene ether) having a number average molecular weight of about 20,000, an intrinsic viscosity in chloroform of 0.40 dl / g at 25 ° C. and a nitrogen content of about 960 ppm

Component (III) -bisphenol A diglycidyl ether and "EPN 1138" of Example 1

Component (IV) -commercially available tert-butyl phenol novolac having an average molecular weight of about 700 to 900.

Component (V): imidazole-amine mixture-a mixture of 1,2-dimethylimidazole and diethylmethylphenylenediamine isomer having an average equivalent weight of about 91.

Component (VI) -zinc acetylacetonate or stearate.

Component: APE 1540-A commercially available colloidal dispersion containing about 40% antimony pentoxide in a polyester resin derived primarily from isophthalic acid.

A commercial colloidal dispersion containing about 75% of antimony pentoxide coated with A-480-amine powder and dispersed in toluene.

Additional ingredients: DOTBP-dioxyl tetrabromophthalate.

A product made by reacting a mixture of brominated epoxy-bisphenol A with 2,2-bis (3,5-dibromo-4-hydroxyphenyl) propane with epichlorohydrin and containing about 21% bromine.

A commercially available compound of formula (VII) wherein phosphate titanate-R ³ is allyl, R ⁴ is methylene, R ⁵ is ethyl, R ⁶ is octyl and X is 0.

[Examples 2 to 8]

A series of curable varnish compositions are prepared by dissolving the components in toluene at a total solid concentration of 35 to 40%. Composition data for the varnish compositions are shown in Table I. All units are by weight except phosphate titanate and basic nitrogen.

TABLE 1

Pieces of glass fiber woven fabric woven to electrical grade are immersed in the varnishes of Examples 2 to 7 and air dried at elevated temperature to remove solvent and to obtain a composite prepreg. Thereafter, compression molding at 230 [deg.] C. and 49.2 kg / cm < 2 > for 5 to 10 minutes produces copper deposited laminates from loz copper foil and eight layers of pregregs. The flame retardancy of the laminate is evaluated according to the Underwriters Laboratories method UL-94. In addition, those prepared from the compositions of Examples 6 and 7 are evaluated by various test methods that constitute part of the US Military Standard MIL-P-13949. The results are shown in Table II below.

TABLE 2a

TABLE 2b

* Not destroyed

Example 9

A 75% solution in toluene of the upstageized composition of Example 1 was prepared and 640 parts (component (I)) thereof were prepared with 2252 parts of hot toluene, 600 parts of component (II), and "EPN 1138" (component (III)). ) 60 parts, component (IV) 120 parts, 2-heptadecylimidazole (component (V) 10.2 parts, zinc acetylacetonate (component (VI)) 24 parts, ADP-480 (component (V)) 42 Mix with 6 parts of phosphate titanate to prepare a curable varnish containing 7.5% bromine, 0.45% zinc, 2.4% antimony pentoxide and 5.5 milliequivalents of basic nitrogen per 100 parts. Glass fiber woven fabric woven to electrical grade is immersed in varnish and air dried at elevated temperature to remove solvent and yield composite prepreg. Thereafter, compression molding at 240 DEG C and 28.1 kg / cm < 2 > for 10 minutes produces a copper deposited laminate from the 10 layers of prepreg.

The laminate is compared with the following control to perform a physical test based on the description of JP-A-58 / 69052.

Phosphatotiti using an upstage composition prepared from 66.7 parts of control A-bisphenol A diglycidyl ether and 33.3 parts of 2,2-bis (3,5-dibromo-4-hydroxyphenyl) propane Same as Example 9 except not using tannate.

A curable composition is prepared from 600 parts of control B-polyphenylene ether, 400 parts of bisphenol A diglycidyl ether, 73 parts of m-phenylenediamine, 1 part of triethylamine hydrochloride and toluene 2252; The 10 layer laminate was molded at 200 ° C. and 28.1 kg / cm 2 for 1 hour. The method is basically the method of Example 2 of the Japanese Laid-Open Patent Publication.

The test results are shown in Table III below.

TABLE 3

When the upsized composition of the present invention is used in combination with phosphate titanate, it is clear that according to the Japanese Laid-Open Patent Publication, a laminate having properties superior to those of the laminate is obtained.

Claims (14)

Contains 5 to 10% of chemically bound bromine; (I) (A) one or more halogen-free bisphenol diglycidyl ethers having an average of one or less aliphatic hydroxy groups per molecule; (B) a mixture containing 15-25% of at least one halogen-free epoxidized novolac and (C) at least 25-35% of at least one bisphenol containing bromine as an aryl substituent, wherein components (B) and (C Percent based on the total weight of components (A), (B) and (C)] containing the reaction product obtained by heating at a temperature ranging from 125 to 225 ° C. in the presence of at least one basic component catalytic amount. Compositions 35-60%, (II) 40-65% of one or more polyphenylene ethers, and (III) halogen-free bisphenol diglycidyl ethers and halogen-free having an average of one or less aliphatic hydroxy groups per molecule Containing 4-10% of one or more polyepoxy compounds selected from the group consisting of epoxidized novolacs, wherein the percentages of components (I), (II) and (III) are based on the weight of the total resin component Dendritic Compound (resinous blend). The combination of claim 1, wherein component (II) is poly (2,6-dimethyl-1,4-phenylene ether). The combination of claim 2, wherein component (III) is an epoxidized novolak and is present in an amount of 4 to 8%. The blend of claim 3 wherein the number average molecular weight of the polyphenylene ether is from 12,000 to 40,000. The combination of claim 4, wherein components (II) and (III) are present in amounts of 35 to 45% and 50 to 60%, respectively. The formulation of claim 5, containing 6 to 9% of chemically bound bromine. The combination according to claim 6, wherein component (A) has the following general formula.

Wherein n has an average of 1 or less. 8. Formulation according to claim 7, wherein component (b) is prepared from formaldehyde, phenol and epichlorohydrin. The combination of claim 8, wherein component (C) is 2,2-bis (3,5-dibromo-4-hydroxyphenyl) propane. The combination of claim 9, wherein n is zero. The combination of claim 10, wherein the polyphenylene ether contains molecules having terminal groups of the general formula:

Wherein each R ² is independently hydrogen or a C _1-6 primary alkyl radical. The combination of claim 11, wherein R ² is each n-butyl. The combination of claim 3 in the form of a solution in an inert organic solvent. The combination of claim 13, wherein the solvent is toluene.