초록 ▼

Curable polycycloolefin resin solutions having particular utility in the fabrication of printed circuit boards are disclosed. A solvent soluble polymer is typically solution polymerized from norbornene-type monomers in the presence of a metathesis catalyst package. This polymer may then be purified

Curable polycycloolefin resin solutions having particular utility in the fabrication of printed circuit boards are disclosed. A solvent soluble polymer is typically solution polymerized from norbornene-type monomers in the presence of a metathesis catalyst package. This polymer may then be purified by precipitation and redissolution. A curing agent, such as a high activation temperature peroxide can then be added to the solution and then this curing agent containing solution can be used to impregnate a suitable substrate such as a fiberglass cloth. The impregnated substrate can then be dried, preferably at temperatures above the glass transition temperature of the polycycloolefin but below the activation temperature of the curing agent. Then one or more prepregs can be stacked and laminated to conductive foil at a temperature high enough to activate the curing agent. Printed circuit boards are obtained which have good resistance to organic solvents such as methylene chloride and to molten solder and which also display good electrical properties such as dielectric constant less than about 3.5 at 1 MHz and a dissipation constant less than about 0.005 at 1 MHz.

대표청구항 ▼

A liquid composition which is suitable for forming a printed circuit board substrate by impregnating a glass fiber cloth, drying the impregnated glass fiber cloth and laminating a conductive foil to at least one surface of the impregnate comprising: (a) a polycycloolefin which is soluble in an organ

A liquid composition which is suitable for forming a printed circuit board substrate by impregnating a glass fiber cloth, drying the impregnated glass fiber cloth and laminating a conductive foil to at least one surface of the impregnate comprising: (a) a polycycloolefin which is soluble in an organic solvent and is capable of undergoing a crosslinking reaction; (b) a curing agent which is activated at a temperature in excess of the glass transition temperature of said polycycloolefin to cause crosslinking of the polycycloolefin; and (c) an organic solvent which substantially dissolves the polycycloolefin and which can be evaporated at a temperature below the activation temperature of the curing agent and above the glass transition temperature of the polycycloolefin.