TH40154A - Composite materials were used in the construction of printed circuit board sheets. - Google Patents

Abstract

DC60 (11/10/42) Composite for use in fabricating printed wiring sheets containing carriers with finely conductive, detachable particles on the surface of the part. The composite is thinned onto the substrate with the finely conductive particles facing the substrate and the detachable carriers, leaving the surface of the finely conductive particles exposed. The printed wiring sheet is formed using the finely conductive particles as a base, providing improved peel strength and allowing for forming with thin wiring lines and spacing. Composite for use in fabricating printed wiring sheets containing carriers containing finely conductive, detachable particles on the surface of the part. The composite is thinned onto the substrate with the finely conductive particles facing the substrate and the detachable carriers, leaving the surface of the finely conductive particles exposed. The printed wiring sheet is formed using the finely conductive particles as a base, providing improved peel strength. Improvements and allowances for shaping with thin lines, spacing, and thin profiles.

Claims (20)

1. Composite material for fabricating printed wiring sheets consisting of a carrier and fine, conductive, releaseable particles prepared on the carrier. 2. Compound materials of claim 1 in which the conductive particle size is 0.1–5.0 micrometers relative to the thickness of the compound. 3. Compound materials of either claim 1 or 2, where the surface roughness (Rz) of the carrier on which fine conductive particles are provided is in the range of 1.0–10.0 µm. 4. A composite material of claim 1 in which the fine conductive particles shall be copper particles. 5. Compound material of claim 1 in which the fine conductive particles shall be copper alloy particles. 6. The composite material of claim 1 in which the release layer shall be placed between the said carrier and the said conductive fine particles. 7. The composite material of claim 1 in which the fine, conductive particles are covered with a coated layer. 8. A thin sheet obtained by thinning the composite material of claim 1 onto the surface of a substrate with fine conductive particles facing the substrate. 9. A thin sheet of claim 8 where the conductive particle size shall be 0.1–5.0 micrometers relative to the thickness of the composite material. 10. The thin sheet of claim 8, on which the surface roughness (Rz) of the carrier on which the fine conductive particles are prepared, shall be in the range of 1.0–10.0 µm. 11. A thin sheet of claim 8 where the fine conductive particles shall be copper particles. 12. A thin sheet of claim 8 where the fine conductive particles shall be copper alloy particles. 13. A thin sheet of claim 8, in which the release layer shall be placed between the said carrier and the said conductive fine particles. 14. A thin sheet of claim 8 in which such fine conductive particles are covered with a coated layer. 15. A thin sheet is obtained by thinning the composite material of claim 1 onto the surface of a substrate with fine conducting particles facing the substrate, and then only the carriers are removed, leaving the fine conducting particles on the substrate. 16. The thin sheet of the claim in clause 15, in which the carrier is removed by uncovering it. 17. The thin sheet of claim 15, in which the carrier is removed by melting. 18. The method of fabricating a printed wiring sheet, consisting of the following steps: a. Surface coating with conductive particles on the carrier; b. Coating of a metal layer over the conductive particles; c. Sheeting of the product of (b) onto at least one substrate surface with the conductive particles facing the substrate; d. Conduction of the carrier away from the sheeted product of (c), leaving the conductive particles on the substrate; e. Forming the printed wiring sheet onto the substrate fabricated in (d) using a panel plating or forming plating process. 19. The method of claim 15 in which the product of step (b) is made into a thin sheet to the opposite surface of the substrate. 20. Method for the fabrication of multi-layer printed wiring sheets in which at least two printed wiring sheets fabricated by means of claim 18 are joined together as thin sheets.