Abstract: A thermosetting composition including an organic solvent, a liquid crystalline thermoset oligomer, and either a crosslinking agent or an epoxy resin or both is disclosed. A printed circuit board which includes the thermosetting composition is also disclosed. The printed circuit board is produced by impregnating the thermosetting composition into a reinforcing material.

Abstract: Disclosed herein is a liquid crystal polyester resin composition and a printed circuit board using the composition. The composition comprises a liquid crystal polyester, a polybenzimidazole and an aprotic solvent. The composition exhibits good thermal stability and has a low dielectric constant. The composition can be advantageously used as a material for printed circuit boards (PCBS) used in semiconductor packages, mobile devices and LCD devices.

Abstract: A prepreg, a prepreg laminate including the prepreg, a metal film laminate including the prepreg, and a printed wiring board including the prepreg. The prepreg includes a woven or non-woven fabric substrate; and an aromatic liquid-crystalline polyester amide copolymer, wherein the woven or non-woven fabric substrate is impregnated with the aromatic liquid-crystalline polyester amide copolymer. Therefore, the prepreg is not deformed or does not cause blisters. In addition, the prepreg has low dielectric properties in a high frequency range. Also, a metal film of the metal film laminate or the printed wiring board does not corrode.

Abstract: A thermosetting composition including an organic solvent, a liquid crystalline thermoset oligomer, and either a crosslinking agent or an epoxy resin or both is disclosed. A printed circuit board which includes the thermosetting composition is also disclosed. The printed circuit board is produced by impregnating the thermosetting composition into a reinforcing material.

Abstract: The invention relates to a method of preparing wholly aromatic polyester including: mixing monomers, introducing the mixed monomers into a reactor having a rectangular or trapezoidal plate type stirring impeller, and polymerizing the introduced monomers through esterification with a power per unit volume of 10˜60 kW/m3, a length (L) to diameter (D) ratio of the stirring impeller is 1˜3:1, and a distance between the bottom of the reactor and a lower portion of the stirring impeller is 1/100˜ 1/15 times of the diameter (D); b) pulverizing the obtained polymer; and c) solid state polymerizing the pulverized polymer.

Abstract: Disclosed herein is a liquid crystal polyester resin composition and a printed circuit board using the composition. The composition comprises a liquid crystal polyester, a polybenzimidazole and an aprotic solvent. The composition exhibits good thermal stability and has a low dielectric constant. The composition can be advantageously used as a material for printed circuit boards (PCBS) used in semiconductor packages, mobile devices and LCD devices.