可溶性聚酰亚胺用于无胶双面挠性覆铜板的研究

Study on Application of Soluble Polyimide in Two-layer Flexible Copper Clad Laminate

使用化学亚胺化法合成可溶性聚酰亚胺,在铜箔上涂布可溶性聚酰亚胺和热塑性聚酰亚胺前驱体混合液,经过高温亚胺化得到无胶单面覆铜板,再与铜箔进行高温压合最终制得无胶双面覆铜板。通过测试双面覆铜板的剥离强度和PI复合膜的玻璃化转变温度、热分解温度、热膨胀系数和介电性能,评价其应用于无胶双面覆铜板的可行性。结果表明:基材的介电常数为2.5~2.7,介质损耗因数为0.004~0.006,剥离强度大于1.0 N/mm,同时热膨胀系数较低。该结构无胶双面覆铜板具有较好的综合性能,可应用于高频高速挠性覆铜板领域。

A soluble polyimide was synthesized by chemical imidization method. The mixture of soluble polyimide and thermal plastic polyimide precursor was coated on the copper foils, and a copper clad laminate was prepared by imidization at high temperature. Then the copper clad laminate was laminated with another copper foil to prepare two-layer flexible copper clad laminate（FCCL）. The peel strength of FCCL and the glass transition temperature, thermal decomposition temperature, thermal expansion coefficient, and dielectric properties of the PI composite film were tested to evaluate the feasibility of its application in FCCL. The results show that the dielectric constant of the substrate is 2.5~2.7, the dielectric loss is 0.004~0.006, the peel strength is above 1.0 N/mm, and the thermal expansion coefficient is low.This kind of FCCL has good comprehensive properties, and it can be used in the field of high frequency and high speed FCCL.