Copolymer of styrene and maleic anhydride comprising an epoxy resin composition and a co-cross-linking agent
View Patent ↗Laminates for printed wiring boards for the making of laminates for printed wiring boards having an impregnant including an epoxy resin, a first cross-linking agent of a strene-maleic anhydride copolymer and a second co-cross-linking agent.
1. A laminate made from a resin composition comprising:
a mixture of:
an epoxy resin that is a derivative of bisphenol A;
a crosslinking agent comprising a copolymer of styrene and maleic anhydride (SMA), and;
at least 5% by weight of a co-crosslinking agent selected from the group consisting of a brominated bisphenol A (BPA), brominated bisphenol A diglycidyl ether (BPADGE), and mixtures thereof.
2. The laminate of claim 1 wherein the copolymer of styrene and maleic anhydride has a molecular weight of about 1400 to about 50,000, and an anhydride content of more than 15% by weight.
3. The laminate of claim 1 , wherein the resin includes an accelerator.
4. The laminate of claim 3 wherein the accelerator is an imidazole.
5. The laminate of claim 1 wherein the resin includes one or more additives selected from the group consisting of dyes, pigments, thixotropic agents, fluidity control agents, and stabilizers.
6. The laminate of claim 1 wherein the resin composition has a ratio of anhydride and aromatic hydroxyl groups: epoxy groups of from 90 to 130%.
7. The laminate of claim 1 wherein the resin composition has a ratio of anhydride and aromatic hydroxyl groups: epoxy groups of from 90 to 110%.
8. The laminate of claim 1 wherein the resin composition is partially cured.
9. The laminate of claim 1 wherein the resin composition is fully cured.
10. A printed circuit board including one or more laminate layers wherein at least one of the laminate layers is the laminate of claim 1 .
11. A laminate made from a resin composition comprising:
a mixture of:
an FR-4 epoxy resin;
a crosslinking agent comprising a copolymer of styrene and maleic anhydride (SMA), and;
at least 5% by weight of a co-crosslinking agent selected from the group consisting of a brominated bisphenol A (BPA), brominated bisphenol A diglycidyl ether (BPADGE), and mixtures thereof.
12. The laminate of claim 11 wherein the amount of copolymer used will give an anhydride and aromatic hydroxyl group: epoxy group equivalency ratio of between 90 and 110%.
13. The laminate of claim 11 wherein the resin composition includes at least 10% by weight of tetrabromobisphenol A and at least 10% by weight tetrabromobisphenol A diglycidyl ether.
14. The laminate of claim 11 wherein the resin composition includes at least 10% by weight of tetrabromobisphenol A diglycidyl ether.
15. The laminate of claim 11 wherein the resin composition is partially cured.
16. The laminate of claim 11 wherein the resin composition is fully cured.
17. A printed circuit board including one or more laminate layers wherein at least one of the laminate layers is the laminate of claim 11 .