Abstract A method and composition of matter useful for rendering an insulating material, self-catalytic to deposition of electroless metal from solutions thereof are shown. A base exchangeable clay material such as hectorite is base exchanged with a source of cations of a metal selected from Group I-B and VIII of the Periodic Table of Elements, preferably nickel or copper, and thereafter, the cation exchanged hectorite is heated under reducing conditions. This thermal treatment activates the exchanged hectorite as a catalyst to induce metal deposition in electroless plating baths. Without such a treatment the exchanged hectorite is not catalytic. The structure of the hectorite is altered by the thermal treatment as it no longer swells or gels when immersed in water. In addition the mechanical strength of the material is increased by the ''''sintering like'''' treatment. The modified base exchanged material can be incorporated or coated on insulating materials to provide the exterior or interior surfaces thereof with a catalytic sensitivity to deposition of electroless metal. The methods and compositions are useful in processes for manufacture of printed circuitry on substrates such as films, glass reinforced laminates, tapes, and boards. Methods of molding printed circuit substrates in desired geometrical form with vias located in predetermined pattern are disclosed along with chemical and mechanical methods of etching the surface of resin to expose base exchanged mineral that serves as the catalyst for electroless plating.
IN A METHOD FOR RENDERING A SUBSTANCE SELFCATALYTIC TO DEPOSITION OF ELECTROLESS METAL IN WHICH HECTORITE IS EMPLOYED AND THE REPLACEABLE CATIONS IN SAID HECTORITE ARE EXCHANGED WITH A CATION OF A METAL SELECTED FROM THE GROUP CONSISTING OF NICKEL, COPPER, PALLADIUM, PLATINUM, GOLD, SILVER, RHODIUM AND IRIDIUM, THE IMPROVEMENT WHICH COMPRISES: MODIFYING THE LATTICE STRUCTURE OF SAID HECTORITE TO STABILIZE IT AGAINST SWELLING WHEN IMMERSED IN AQUEOUS ELECTROLESS SOLUTIONS BY REDUCING THE EXCHANGE METAL CATIONS AT ELEVATED TEMPERATURES IN A REDUCING ATMOSPHERE CONSISTING ESSENTIALLY OF A COMPOUND SELECTED FROM THE GROUP CONSISTING OF HYDROGEN CARBON MONOXIDE, HYDROGEN SULFIDE AND CRACKED AMMONIA.
Claim 2
Dependent Claim
102 words
IN A METHOD FOR RENDERING A SUBSTANCE SELFCATALYTIC TO DEPOSITION OF ELECTROLESS METAL IN WHICH HECTORITE IS EMPLOYED AND THE REPLACEABLE CATIONS IN SAID HECTORITE ARE EXCHANGED WITH A CATION OF A METAL SELECTED FROM THE GROUP CONSISTING OF NICKEL, COPPER, PALLADIUM, PLATINUM, GOLD, SILVER, RHODIUM AND IRIDIUM, THE IMPROVEMENT WHICH COMPRISES: MODIFYING THE LATTICE STRUCTURE OF SAID HECTORITE TO STABILIZE IT AGAINST SWELLING WHEN IMMERSED IN AQUEOUS ELECTROLESS SOLUTIONS BY REDUCING THE EXCHANGE METAL CATIONS AT ELEVATED TEMPERATURES IN A REDUCING ATMOSPHERE CONSISTING ESSENTIALLY OF A COMPOUND SELECTED FROM THE GROUP CONSISTING OF HYDROGEN CARBON MONOXIDE, HYDROGEN SULFIDE AND CRACKED AMMONIA.
Claim 3
Dependent Claim
85 words
In a method for rendering a substance selfcatalytic to deposition of electroless metal in which hectorite is employed and the replaceable cations in said hectorite are replaced with cations of nickel, the improvement which comprises: modifying the structure of said hectorite and stabilizing it against swelling when immersed in aqueous electroless solutions, by reducing said cations of nickel by maintaining said base exchanged hectorite in an atmosphere of hydrogen at a temperature of from 100* to 600*C, and at times from 5 to 15 minutes.
Claim 4
Dependent Claim
85 words
In a method for rendering a substance selfcatalytic to deposition of electroless metal in which hectorite is employed and the replaceable cations in said hectorite are replaced with cations of nickel, the improvement which comprises: modifying the structure of said hectorite and stabilizing it against swelling when immersed in aqueous electroless solutions, by reducing said cations of nickel by maintaining said base exchanged hectorite in an atmosphere of hydrogen at a temperature of from 100* to 600*C, and at times from 5 to 15 minutes.