Varnish composition, and pre-impregnated manufacture thereof
A varnish composition includes composition (A): an epoxy resin, composition (B): a hardener, composition (C): an accelerator, composition (D): phosphor-containing flame retardant, and composition (E): fillers, wherein composition (A) includes composition (A-1): phosphor-containing epoxy resin, phosphor-containing and silicon-containing epoxy resin, or a mixture thereof; composition (A-2): dicyclopentadiene epoxy resin; and composition (A-3): oxazolidone epoxy resin.
1. A varnish composition comprising:
composition (A): an epoxy resin including:
composition (A-1): a phosphorus containing epoxy resin, a phosphorus and silicon containing epoxy resin, or a mixture thereof;
composition (A-2): dicyclopentadiene epoxy resin; and
composition (A-3): oxazolidone epoxy resin;
composition (B): a hardener, wherein the hardener of composition (B) is a polymer of styrene and maleic acid anhydride, a benzoxazine resin, or a mixture thereof;
composition (C): an accelerant;
composition (D): phosphorus-containing flame retardant; and
composition (E): fillers,
wherein the dicyclopentadiene epoxy resin of composition (A-2) is shown as formula 4:
wherein “i” represents a number of repeat units.
2. A prepreg prepared by applying the varnish composition of claim 1 to a composite fabric.
3. A substrate of printed circuit board prepared by laminating the prepreg of claim 2 .
4. The varnish composition according to claim 1 , wherein the phosphorus-containing epoxy resin of composition (A-1) is an epoxy resin formed with a phosphorus-containing reactant selected from the group consisting of formula 1, formula 2, and formula 3 as listed below:
5. The varnish composition according to claim 1 , wherein the phosphorus and silicon containing epoxy resin of composition (A-1) is an epoxy resin formed with a silicon-containing reactant and a phosphorus-containing reactant selected from the group consisting of formula 1, formula 2, and formula 3 as listed below:
6. The varnish composition according to claim 1 , wherein the oxazolidone epoxy resin of composition (A-3) is shown as formula 5:
7. The varnish composition according to claim 1 , wherein the composition (A) further includes composition (A-4): naphthalene epoxy resin.
8. The varnish composition according to claim 7 , wherein the naphthalene epoxy resin of composition (A-4) is shown as formula 6:
wherein “n” represents a number of repeat units.
9. The varnish composition according to claim 1 , wherein the benzoxazine resin of composition (B) is shown as formula 7:
wherein “R” is a composition selected from the group consisting of S, CH2,