CA1277579C - Laminates - Google Patents

Abstract

ABSTRACT

Laminates are prepared from reinforced epoxy resin compositions comprising (A) a reinforcing material such as fiberglass, (B) one or more epoxy resins such as a hydrocarbon-phenol epoxy resin and (C) one or more epoxy resin curing agents such as a hydrocarbon-phenol resin or phenol-formaldehyde novolac resin. These laminates are particularly suitable for use in electrical applications such as the manufacture of printed circuit boards.

Description

~'~77579 LAMINATES
The present invention pertains to laminates, particularly electrical laminates.
Laminates have previously been prepared from bisphenol A based epoxy resins. It is known that the properties of a laminate can be improved by employing multifunctional epoxy novolac resins in the formulations. It is also known that just as significant as the improvements in laminate properties is the detrimental effect that multifunctional epoxy resins have on processability. The tris(hydroxy-phenyl)methane, tetra(hydroxyphenyl)ethane and phenol-formaldehyde epoxy novolac resins have beenunsuccessful toward this end because to achieve a glass transition temperature (Tg) of 150C or higher, whencured with dicyandiamide, requires sufficient quantities of the multifunctional epoxy resin to have ~dverse effects in the following areas: (l) varnish reactivity, (2) prepreg reactivity, (3) prepreg cosmetics, (4) reinforcement wetability, (5) laminate pressing, (6) laminate post cure requirement and (7) blister resistance oE the laminate.

33,261B-F -1-.
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It has now been discovered that these deficiencies can be overcome by the use of hydrocarbon-phenol epoxy resins. They not only provide theelectrical laminates prepared therefrom an improvement in electrical and moisture resistance properties, but they also provide an improvement in one or more of the 0 above enumerated deficlencies.
The present invention concerns laminate which has a Tg of at least 150C prepared from a cured composition comprising (A) at least one reinforcing material;
(B) at least one epoxy resin; and (C) at least one curing agent for component (B);
characterized by employing as at least a part of component (B), at least one hydrocarbon-phenol epoxy resin or halosenated hydrocarbon-phenol epoxy resin in an amount such that at least 40, preferably from 90 to lO0 percent of the epoxy groups present in component (~) are contributed by said hydrocarbon-phenol epoxy resin, halogenated hydrocarbon-phenol epoxy resin. or combinatin thereof.
Suitable hydrocarbon-phenol epoxy resins which can be employed herein include those disclosed by Vegter et al in U.S. Patent 3,536,734, by Nelson in U.S. Patent 4,390,680 and Nelson et al in U.S. Patent 4,394,497. Particularly suitable hydrocarbon-phenol epoxy resins include those prepared by dehydrohalogenating the reaction product of an 33,261B-F -Z-.
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77~'73 epihalohydrin and the reaction product of an aro~atic hydroxyl-containing compound with an unsaturated hydrocarbon having from 4 to 55 carbon atoms. Suitable aromatic hydroxyl-containing compounds which can be employed herein include any such compounds which contain one or two aromatic rings, at least one phenolic hydroxyl group and at least one ortho or para ring position with respect to a hydroxyl group available for alkylation.
Particularly suitable aromatic hydroxyl-containing compounds which can be employed herein include, for example, phenol, chlorophenol, bromophenol, methylphenol, hydroquinone, catechol, resorcinol, guaiacol, pyrogallol, phloroglucinol, isopropylphenol, ethylphenol, propylphenol, t-butylphenol, isobutylphenol, octylphenol, nonylphenol, cumylphenol, p-phenylphenol, o-phenylphenol, m-phenylphenol, bisphenol A, dihydroxydiphenyl sulfone, or mixtures thereof.
Suitable unsaturated hydrocarbons which, either in a crude or purified state, can be employed herein include, for example, butadiene, isoprene, piperylene, cyclopentadiene, cyclopentene, 2-methylbutene-2, cyclohexene, cyclohexadiene, methyl cyclopentadiene, dicyclopentadiene, limonene, dipentene, linear and cyclic dimers of piperylene, methyl dicyclopentadiene, ~0 dimethyl dicyclopentadiene, norbornene, norbornadiene, ethylidine norbornene, and mixtures thereof. Also suitable unsaturated hydrocarbons include the other dimers, codimers, oligomers and cooligomers of the aforementioned unsaturated hydrocarbons. Particularly suitable unsaturated hydrocarbons which can be employed herein include, for example, a dicyclopentadiene 33,261B-F -3-'~ ~ ' - ~ ' '' .

~77~79 concentrate containing from 70 to lO0 percent by weight of dicyclopentadiene; from 0 to 30 percent by weight of C8-Cl2 dimers or codimers of C4-C6 dienes such as, for example, cyclopentadieneisoprene, cyclopentadiene-piperylene, cyclopentadienemethyl cyclopentadiene,and/or dimers of isoprene, piperylene, methyl cyclopentadiene and the like; from zero to 7 percent by weight of Cl2-Cl8 trimers of C4-C6 dienes and from zero to lO percent by weight of aliphatic diolefins such as, for example, piperylene, isoprene, l,5-hexadiene and cyclic olefins such as cyclopentadiene, methyl cyclopentadiene, cyclopentene and the like. Methods of preparation for these dicyclopentadiene concentrates and more detailed descriptions thereof can be found collectively in U.S. ~atent No. 3,557,239 issued to Gebhart et al and U.S. Patent No. 4,167,542 issued to Nelson.
Also, particularly suitable unsaturated hydrocarbons which can be employed herein include a crude dicyclopentadiene stream containing from 20 to 70 percent by weight dicyclopentadiene, from 1 to lO
percent codimers and dimers of C4-C6 hydrocarbons (described above), from zero to lO percent oligomers of C4-C6 dienes and the balance to provide lO0 percent, C4-C6 alkanes, alkenes and dienes.
Also, particularly suitable unsaturated hydrocarbons which can be employed herein include a crude piperylene or isoprene stream containing from 30 to 70 percent by weight piperylene or isoprene, zero to ten percent by weight C8-C12 dimers and codimers of C4-C6 dienes, and the balance to provide 100% C4-C6 alkanes, alkenes and dienes.

33,261B-F -4-~' `
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7757~3 Also, particularly suitable are hydrocarbon oligomers prepared by polymerization of the reactive components in the above hydrocarbon streams e.g., dicyclopentadiene concentrate, crude dicyclopentadiene, crude piperylene or isoprene, individually or in combination with one another or in combination with high purity diene streams.

These hydrocarbon-phenol epoxy resins can be employed alone or in admixture with other epoxy resins such as the diglycidyl ethers of dihydric phenols such as, for example, resorcinol, catechol, hydroquinone, bisphenol A, bisphenol F, dihydroxybiphenyl, and mixtures thereof. Also suitable are the polyglycidyl ethers of phenolic materials having more than two hydroxyl groups such as, for example, tris(hydroxy-phenyl)methane, tetra(hydroxyphenyl)ethane, phenol-aldehyde novolacs, and mixtures thereof. Also, suitable are the halogenated derivatives, particularly the brominated derivatives of the aforementioned epoxy resins.

Suitablé curing agents which can be employed herein include, for example, amines, acids or anhydrides thereof, biguanides, imidazoles, urea-aldehyde resins, melamine-aldehyde resins, phenolics, halogenated phenolics, combinations thereof and the like. These and other curing agents are disclosed in Lee and Neville's Handbook of EpoxY Resins, McGraw-Hill Book Co., 1967. Particularly suitable curing agents include, for example, dicyandiamide, diaminodiphenyl-sulfone, 2-methylimidazole, diethylene- toluenediamine, bisphenol A, tetrabromobisphenol A, phenol-formaldehyde 33,261B-F -5-~,~77st~'~

novolac resins, halogenated phenol-formaldehyde resins, hydrocarbon-phenol resins and combinations thereof.
Suitable reinforcing materials which can be employed herein include, for example, fiberglass, aromatic polyamides, aramid resins, carbon, graphite, quartz, synthetic fibers, and combinations thereof.
The reinforcing materials can be woven, matt, filament or in the form of random ~ibers.
Suitable catalysts or promoters or accelerators which can be employed in the preparation of the prepreg materials from which the laminates are prepared include, for example, tertiary amines, imidazoles, phosphonium compounds, ammonium compounds, sulfonium compounds, and mixtures thereof.
Suitable tertiary amines include, for example, triethylenediamine, N-methylmorpholine, triethylamine, tributylamine, benzyldimethylamine, trisldimethylamino-methyl)phenol, and mixtures thereof.
Suitable imidazoles include, for example, 2-methylimidazole, l-propylimidazole, and mixtures thereof.
Suitable phosphonium compounds include, for example, those clisclosed by Dante et al in U.S.
3,477,990, Perry in Canadian Patent 893,l9l and U.S.
3,948,855 and by Tyler, Jr. et al in U.S. 4,366,295.
Suitable quaternary ammonium compounds include, for example, benzyl trirnethyl ammonium chloride, benzyl trimethyl ammonium hydroxide, tetrabutyl ammonium 33,261B-F -6-.
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~ ~'77579 chloride, tetrabutyl ammonium hydroxide, and mixtures thereof.
Suitable solvents which can be employed to prepare the electrical laminates include, for example, glycol ethers, ketones, aromatic hydrocarbons, alcohols, amides, and combinations thereof.
Particularly suitable solvents include, for example, 0 methyl ethyl ketone, acetone, methanol, dimethylformamide, ethylene glycol methyl ether, propylene glycol methyl ether, and combinations thereof.
The laminates of the present invention are suitable for use in electrical applications, structural laminates or composites and the like. They are particularly suitable for use in the manufacture of printed circuit boards.
The printed circuit boards, of course, have an outer layer oE an electrical conductive material such as copper, gold, silver, platinum and the like.
The following examples are illustrative of the invention, but are not to be construed as to limiting the scope thereof in any manner.
EPoxy Resin A i8 a phenol-ormaldehyde epoxy novolac resin having an average functionality of 3.8 and an epoxide equivalent weight, EEW, of 200.
EpoxY Resin B is a glycidyl ether of tris-(hydroxyphenyl~methane novolac (the reaction product of hydroxybenzaldehyde with phenol in a molar ratio of 1 33,261B-F -7_ - . - : -.

~ ~77579 to 4 respectively) having an average functionality of 5.9 and an epoxide equivalent weight, EEW, of 218.
Epoxy Resin C is the glycidyl ether of the reaction product of phenol and a dicyclopentadiene concentrate consisting of 83~ DCPD, 1.4% non-reactive light hydrocarbons, and the remainder bein~ primarily a mixture of codimers of C4-C6 dienes. This resin has an 0 average functionality of 3.2 and an epoxide equivalent weight, EEW, of 279.
Resin Varnish Preparation Procedure In the Example and Comparative Experiments, the resin varnish was prepared from the indicated formulation in the following manner.
The indicated amount of epoxy resin solution was blended with the indicated amount of dicyandiamide solution. 2-Methylimidazole was added, if necessary, to adjust the varnish reactivity to approximately 200 seconds by stroke cure gel time. Additional acetone was added, if necessary, to bring the overall varnish viscosity to 21 seconds by a #2 Zahn cup.
The tests were performed according to the following procedures. The relative blister resistance was determined by placing three 2" ~ 4" ~50.8 mm x 101.6 mm3 unclad laminate coupons in a pressure pot at 15 psi (103 kPa) steam for 60 minutes and 120 minutes.
After this time the co~pons were removed, externally dried and dipped in molten solder at 500F (260C) for 20 seconds. Each side of the 3 coupons was then inspected for any delamination blisters. The results were reported as the percent of number of sides with no blisters. Degrees of cure were measured by glass 33,261B-F -8-.

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~7~79 g transition temperatures and/or exotherms as evidenced on a DuPont 1090 Thermal Analyzer with a 910 Differential Scanning Calorimeter (DSC). All gel times were measured by stroke cure on a 171C hot plate.

The resin Elow is a measure of the amount of resin that will be expelled during a pressing operation. The ~ flow is measured by the following procedure:
1. cut six 6" x 6" (152.4 mm x 152.4 mm) squares f prepreg;

2. stack the 6 pieces and weigh to the nearest i.01 gram;

3. put the stack between caul plates and place into a preheated press at 340F (171.1C) and apply a pressure of 200 psi (1379 kPa);

4. leave in the press for at least 10 minutes;

5. remove the pressed laminate and cut into a 4" x 3 4" (101.6 mm x 101.6 mm) piece;

6. weigh the 4" x 4" (101.6 mm x 101.6 mm) piece to the nearest +.01 gram; and 7. the fol:Lowing calculation is used to determine % flow:
% flow - initial weiqht/2 - final wei~ht initial weight/2 33,261~-F -9-.77579 1 o -COMPARATIVE EXPERIMENT A
A. Formulation A varnish was prepared employing the aforemen-tioned procedure employing the following formulation.
4292 grams (18.241 equiv.) of an 85~ by weight solution of Epoxy Resin A in methyl ethyl ketone.
2287 grams (10.95 equiv.) of a 10% by weight solution of dicyandiamide in a 50/50 by weight solvent blend of dimethylformamide and propylene glycol methyl ether.
500 grams of acetone to adjust solution viscosity.

B. Preparation of Preimpreqnated Substrate Burlington style 7628 glass cloth with an I-617 finish was impregnated with the above varnish formulation. The impregnation was done in a forced air vertical treater having a total length of 36 feet (10.97 m). The first 27 feet (8.23 m) were heated to 350F (176.7C). The last 9 feet (2.74 m) were not heated. The treater was operated at rates of 11, 13, 15 and 17 feet per minute (55.88, 66.04, 76.2 and 86.36 mm/s). The resultant preimpregnated glass cloth had a gel time of 124 seconds except for the one prepared at 11 ft./min. (55.88 mm/s) which gelled (0 gel time).
The resin content of the impregnated glass cloth was 37% by weight.

33,261B-F -10-7~79 C. Preparation of Laminate A single opening Wabash press was preheated to 350F (176.7C). ~ight plys of 12" x 12" (304.8 mm x 304.8 mm) preimpregnated glass cloth prepared in (B) above was placed between 2 steel plates and Teflon pads. The above lay-up was placed into the press and a minimal amount of pressure, 30 psig (206.844 kPa) was applied to help control the laminate thickness and resin flow. At 5 minutes, the pressure was increased gradually to 500 psig (3447.4 kPa).
The results were as follows: (1) The varnish gel time was 124 seconds. This is considerably faster than the typical 200 second gel time especially since there was no accelerator (2-methylimidazole) added.
(2) The prepreg cosmetics (uniformity of resin coating on the glass) was in all instances very poor. The surface was very rough and mottled. (3) The impregnation of the glass (wetability) was very poor.
If properly wet out, the prepreg should be translucent.
In this instance, the prepreg was virtually opaque.
(4) ~he excessive resin flow during lamination, even with an initial low pressure period, caused resin starved areas in the laminate. (5) The very rapid build in viscosity as evidenced by the dynamic mechanical spectroscopy (DMS) cur~es caused considerable air entrapment in the laminate. (6) ~0 During the typical 1 hour , 500 psig (3447.4 kPa) press cycle at 350F (176.7C) the laminate did not reach full cure. Even after a post bake cycle of 16 hours at 175C, the laminate was still not fully cured. (7) A
blister resistance test of 60 and 120 minutes exposure to 15 psig (103.4 kPa) steam followed by immersion in 500F (260C) solder for 20 seconds was conducted and at 33,261B-F -11-. - . ~ .
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~ ~77579 60 min., 50% of the samples passed and at 120 min., none of the samples passed. (8) The dielectric constant was 5.64 and the dissipation factor was 0.0080.

COMPARATIVE EXPERIMENT B
A. Preparation of Varnish A varnish was prepared employing the procedure in part A of Comparative Experiment A employing the following formulation.
4301 grams (13.81 equiv.) of a 70~ by weight solution of Epoxy Resin B in methyl ethyl ketone.
1740 grams (8.9 equiv.) of a 10% by weight solution of dicyandiamide in a 50/50 by weight solvent blend of dimethylformamide and propylene glycol methyl ether.
No acetone was added, as no viscosity adjust-ment was required.
B. Preparatlon of Preimpreqnated Substrate The same glass cloth, vertical treater and treater conditions were employed in this experiment as in part B of Comparative Experiment A. The treater was operated at 16 feet per minute (81.28 mm/s). The resultant preimpregnated glass cloth had a gel time of 92 seconds. The resin content was 41% by weight.
C. Preparation of Laminate The same press conditions and press cycle were employed in this experiment as in part C of Comparative 33,261B-F -12-. , .

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' ' ' : ' ' - -Experiment A. The results were as follows: (1) The gel time of the varnish from which the laminate was prepared was 147 seconds. This is considerably faster than the typical 200 second gel time, especially since there was no accelerator (2-methylimidazole) present.
(2) The prepreg cosmetics were very poor. The surface was very rough and mottled. (3) The wet-out of the glass cloth was very poor. The prepreg was virtually opaque. (4) The excessive resin flow even during the low pressure cycle caused resin starved areas. (5) The rapid build in viscosity near the gel point (similar to that of Comparative Experiment A) as evidence by the DMS curves caused considerable air entrapment in the laminate. (6) During the typical 1 hour, 500 psig (3447.4 kPa), press cycle at 350F (176.7C), the laminate did not reach full cure as evidenced by an exotherm at 205~C during DSC analysis. Even after a 16 hour post cure at 175C, the laminate exothermed at 220C again indicating an incomplete cure. (7) A
blister resistance test of 60 and 120 minutes exposure to 15 psig (103.4 kPa) steam Eollowed by immersion in 3 500F (260C) solder for 20 seconds was conducted and at 60 min., 100% of the samples passed and at 120 min., none of the samples passed.

A. PreParatio _of Varnish A varnish was prepared employing the procedure part A of Comparative Experiment A employing the following formulation.
4939 grams (14.15 equiv.) of an 80~ by weight solution of Epoxy Resin C in acetone.

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, 77~79 1782 grams (8.49 equiv.) of a 10~ by weight solution of dicyandiamide in a 50/50 by weight solvent blend of dimethylformamide and propylene glycol methyl ether.

2.77 grams of 2-methylimidazole to adjust the reactivity.
400 grams of acetone were added to adjust the solution viscosity.
B. PreParation of Preimpreqnated Substrate The same glass cloth, vertical treater and treater conditions were employed in this experiment as in part B of Comparative Experiment A. The treater was operated at 8.5 feet per minute (43.18 mm/s). The resultant preimpregnated glass cloth had a gel time of 150 seconds. The resin content was 40% by weight.
C. Preparation of Laminate The same press conditions and press cycle were 3 employed in this example as in part C of Comparative Experiment A. The results were as follows: (1) The varnish formulation was accelerated with 2-imidazole to obtain the typical 200 second gel time. (2) The prepreg cosmetics were excellent. The surface was very smooth and even. (3) The wetability of the glass cloth was very good. The prepreg was translucent which is indicative of good wet-out. (4) There were no resin starved areas on the laminate even though the prepreg had a longer gel time than that of Comparative Experiment A. (5) There was no air entrapped in the laminate. (6) Full cure of the laminate was achieved in the 1 hour press cycle. The glass transition 33,261B-F -14_ . .

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temperature (Tg) was 185C as determined by DSC, differential scanning calorimetry. Following a 16 hour post cure at 175C, there was no significant increase in the Tg indicating that full cure is achieved in the l hour press cycle. (7) A blister resistance test of 60 and 120 minutes exposure to 15 psig (103.422 kPa) steam followed by immersion in 500F (260C) solder for 20 seconds was conducted and at 60 min., 83% of the samples passed and at 120 min., 83% of the samples passed. (8) The dielectric constant was 4.75 and the dissipation factor was 0.00696.
The results of Comparative Experiments A and B
and Example 1 are tabulated in the following table.

33,261B-F -15_ . . : .

-16- ~77~79 Comparative Example Experiments A B
Varnish Reactivity, seconds 124 147 200 Prepreg Reactivity, seconds 124 92 150 Prepreg Appearance Poor Poor Excellent Glass Wetability Poor Poor Excellent Resin Flow, % 60 50 25 Blister Resistance (120 min.) Sides with no blisters0 0 83 5 ~ielectric Constant @ 1 KHZ5.645.25 4.75 *Residual Exotherm ~after 16 hours @ 175C) Yes Yes No 20 **Amount of 2-methylimidazole required for reactivity adjustment 0 0 2.77 *Residual exotherm is an indication that the reaction mixture was not totally cured, i.e. a reaction was still taking place.
**Amount of 2-methylimidazole required to adjust the reactivity so that the gel time of the reaction mixture was approximately 200 seconds.
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~:77S79 A. Preparation of Varnish A varnish was prepared employing the procedure of Comparative Experiment A, Part A from the following components.
124 grams (0.46 epoxy equiv.) of Epoxy Resin C.
44 grams (0.16 phenolic hydroxyl equiv.) of tetrabromobisphenol A.
62 grams (0.35 phenolic hydroxyl equiv.) of a novolac resin prepared by reacting phenol with a mixture consisting of 83% dicyclopentadiene, 1.4% non-reactive liqht hydrocarbons and the remainder being primarily a mixture of codimers of C4-C6 dienes. This resin had an average functionality of 3.2 and a phenolic hydroxyl equivalent weight of 176.9.
0.35 grams of 2-methyl imidazole.
92 grams of acetone.
31 grams of propylene glycol methyl ether.
B. Preparation f Preimpreqnated Substrate.
Strips of 6 in. (152.4 mm) wide 7628 style fiberglass cloth were dipped into the above solution and dried in a forced draft oven at 350F (176.6C) for 90 sec. The resultant preimpregnated substrate material contained 41.8% resin, 58.2% glass and had a gel time of 131 seconds at 345C.

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- 1 8~ 7579 C. Preparation of Laminate Eight layers of the above preimpregnated substrate material were pressed in an electrically heated press under the following conditions, each step being sequential:
80~(26.7C~ to 290F (143.3C) at 12F/min (0.1157C/sec.) at 35 psig (241.3 kPa);
290F!143.3C) to 350F (176.7C) at 12F/min (0.1157C/sec.) and the pressure increased to 450 psig (3102.7 kPa) at a rate of 140 psig/min (16.09 kPa/sec);
maintained at 350F (176.7C) and 450 psig (3102.7 kPa) for 90 min.
cooled from 350F (176.7C) to 150F (65.6C) at -20F/min (-0.185C/sec). and a pressure of 450 psig (3102.7 kPa).
The press was then opened and the laminate removed. The laminate had the following properties.
Glass transition temp. (heated at 20C/min) ....167C.
Thickness......................................... 58 mils (0.147 mm)Resin 35 Flow.................................................................... 8%
Uniformly translucent over entire area. Dielectric constant at 100 KHz .................................................. 4.5 33,261B-F -18-.

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A. Preparation of Varnish A varnish was prepared employing the procedure of Compartive Experiment A, Part A employing the following components.

121 grams (0.45 epoxy equiv.) of Epoxy Resin C.
50.6 grams (0.19 phenolic hydroxyl equiv.~ of terabromobisphenol A.
24~5 grams (0.22 phenolic hydroxyl equiv.) of phenol-formaldehyde novolac resin having an average functionality of 5 and a phenolic hydroxyl equivalent weight of 110 .

0.3 grams of 2-methyl imidazole.
112 grams of acetone.
2.5 grams of propylene glycol methyl ether.
B. Preparation of PreimPreqnated Substrate.
Strips of 6 in. (152.4 mm) wide 7628 style fiberglass cloth were dipped into the above solution and dried in a forced draft oven at 350F (176.6C) for 90 sec. The resultant preimpregnated substrate material contained 42.4% resin, 57.6~ glass and had a gel time of 107 seconds at 345C.
C. Preparation of Laminate Eight layers of the above preimpregnated substrate material were pressed in an electrically 33,261B-F -19-.

, 1.;~7~579 heated press under the following conditions, each step being se~uential:
80F(26.7C) to 275F (135C) at 12F/min (0.1157C/sec.) at 35 psig (241.3 kPa);
275F(135C) to 350F (176.7C) at 12F/min (0.1157C/sec.) and the pressure increased to 350 psig (2413.2 kPa) at a rate of 160 psig/min (18.39 kPa/sec); maintained at 350F (176.7C) and 350 psig (2413.2 kPa) for 90 min.
350F (176.7C) to 150F (65.6C) at -20F/min (-0.185C/sec) and a pressure of 350 psig ((2413.2 kPa);

The press was then opened and the laminate removed. The laminate had the following properties.
Glass transition temp. (heated at 20C/min)...... 175C.

Thickness.......................... 580 mils (0.127 mm) Resin Flow......................................... 8%.
3o Uniformly translucent over entire area.
Dielectric constant at 100 KHz ................... 4.6.

Blister resistance...................................... 66.6%.

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Claims (10)

1. A laminate having a Tg of at least 150°C
prepared from a cured composition comprising (A) at least one reinforcing material;
(B) at least one epoxy resin; and (C) at least one curing agent for component (B);
characterized by employing as at least a part of component (3) at least one hydrocarbon-phenol epoxy resin, halogenated hydrocarbon-phenol epoxy resin or combination thereof in an amount such that at least 40 percent of the epoxy groups present in component (B) are contributed by said hydrocarbon-phenol epoxy resin, halogenated hydrocarbon-phenol epoxy resin or combination thereof.

2. A laminate of Claim 1 wherein (i) component (A) is fiberglass or an aromatic polyamide;
(ii) component (C) is an amine, a biguanide or a phenolic material; characterized in that C-33,261-3 -21-(iii) component (B) is (1) a hydrocarbon-phenol epoxy resin, (2) a halogenated hydrocarbon-phenol epoxy resin, (3) a combination of a hydrocarbon-phenol epoxy resin and a halogenated hydrocarbon-phenol epoxy resin, (4) a combination of (a) a hydrocarbon-phenol epoxy resin or a halogenated hydrocarbon-phenol epoxy resin or combination thereof and (b) a phenol-aldehyde epoxy novolac resin, a halogenated phenol-aldehyde epoxy novolac resin, a bisphenol A based epoxy resin, a halogenated bisphenol A based epoxy resin or any combination thereof; and (iv) said hydrocarbon-phenol epoxy resin or halogenated hydrocarbon-phenol epoxy resin is present in an amount such that from 90 to 100 percent of the epoxy groups present in component (B) are contributed by said hydrocarbon-phenol epoxy resin or halogenated hydrocarbon-phenol epoxy resin or combination thereof.

3. A laminate of Claim 2 wherein (i) component (C) is dicyandiamide, diamino-diphenylsulfone a phenol-formaldehyde resin, a hydrocarbon-phenol resin, or a combination thereof; and (ii) component (B) is the product resulting from dehydrohalogenating the reaction product of an epihalohydrin and the product resulting from reacting phenol, cresol or a C-33,261-B -22-combination thereof with (a) an unsaturated hydrocarbon containing an average of from 6 to about 55 carbon atoms per molecule or halogenated derivatives of such reaction products, or mixture of such hydrocarbons or halogenated derivatives thereof; (b) oligomers and/or cooligomers of hydrocarbon dienes, which dienes have from 4 to 18 carbon atoms or mixture of such hydro-carbons or halogenated derivatives thereof or (c) a combination of (a) and (b).

4. A laminate of Claim 2 wherein (a) component (C) is dicyandiamide, diaminodiphenylsulfone, a phenol-formaldehyde novolac resin, a hydrocarbon-phenol resin, or a combination thereof; and (b) component (B) is (i) the product resulting from dehydrohalogenating the reaction product of an epihalohydrin and the product resulting from reacting phenol, cresol or a combination thereof with a composition comprising from about 70 to about 100 percent by weight of dicyclopentadiene, from about zero to about 30 percent by weight of C10 dimers, from about zero to about 7 percent by weight of oligomers of C4-C6 unsaturated hydrocarbons and the balance if any to provide 100% by C-33,261-B -23-weight of C4-C6 alkanes, alkenes or dienes;
(ii) halogenated derivatives of the product of component (i); or (iii) combination thereof.

5. A laminate of Claim 1 which is an electrical laminate.

6. An electrical laminate of Claim 5 which is a printed circuit board.

7. A laminate of Claim 2 which is an electrical laminate.

8. An electrical laminate of Claim 7 which is a printed circuit board.

9. A laminate of Claim 3 which is an electrical laminate.

10. An electrical laminate of Claim 9 which is a printed circuit board.

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