| abstract |
Printed circuit boards (PCB) comprising (A) an insulating substrate with a conducting circuit on it, (B) an insulating adhesive layer formed on this, (C) a number of conducting wires with an insulating coating fixed in the adhesive layer, and (D) a number of metal-coated through-holes at the points required for electrical connection. Layer (B) has an elastic storage modulus at 300 deg C of 30 MPa or more and a glass transition pt. (Tg) of 180 deg C or higher, and is made from an adhesive composition (I) containing (a) a polyamide-imide resin (PAI) and (b) a heat-hardening component. Also claimed is (i) a process for the production of PCB, (ii) multilayer PCB comprising several insulating substrates with circuits as above, adhesive layers of material (I) between the substrates, and metal-plated through- holes as required; (iii) a process for the production of multi- layer PCB; (iv) a process for the production of multilayer PCB with formation of an interlayer substrate (ILS); (v) printed circuit boards for chip carriers; (vi) processes for the production of PCB for chip carriers; (vii) adhesive composition (I) with the above properties when hardened; (viii) a process for the formation of an insulating adhesive layer (B) for the above applications, by using a composition (I) containing (a) 100 pts. wt. PAI resin and (b) 10-150 pts. wt. epoxy resin with hardener and/or hardening accelerator. |