Baseboard for printed circuit board

Claim 2

A baseboard for a printed circuit board which comprises a metal substrate having through-holes and a resin coating covering the overall surface of the metal substrate including the inner wall surfaces of the through-holes, characterized in that said resin coating comprises at least one coat layer of resin covering the upper and lower surfaces and the inner walls of the through-holes of the metal substrate and having, at the circumferential edges formed by the intersection of the upper and the lower surfaces of said metal substrate with the inner walls of said through-holes, a thickness that is greater than that on said upper and said lower surfaces of the metal substrate.

Claim 3

A baseboard for a printed circuit board according to claim 1, characterized in that said at least one coat layer is an insulating resin coat layer.

Claim 4

A baseboard for a printed circuit board according to claim 1, characterized in that said at least one coat layer is an adhesive resin coat layer.

Claim 5

A baseboard for a printed circuit board according to claim 1, characterized in that said at least one coat layer is an insulating adhesive resin coat layer.

Claim 6

A baseboard for a printed circuit board according to claim 2, characterized in that on said insulating resin coat layer there is provided at least one adhesive resin coat layer.

Claim 7

A baseboard for a printed circuit board according to claim 5, characterized in that said at least one adhesive resin coat layer is formed on the overall surface of said insulating resin coat layer and has, at the circumferential edges of the through-holes, a thickness that is greater than that on said insulating resin coat layer on the upper and the lower surfaces of the metal substrate.

Claim 8

A baseboard for a printed circuit board according to claim 5 characterized in that said at least one adhesive resin coat layer is formed on the overall surface of said insulating resin coat layer and has, at the circumferential edges of the through-holes, an adhesive resin coat layer thickness that is smaller than that on said insulating resin coat layer on the upper and lower surfaces of the metal substrate.

Claim 9

A baseboard for a printed circuit board according to claim 3, characterized in that under said adhesive resin coat layer there is provided at least one insulating resin coat layer.

Claim 10

A baseboard for a printed circuit board according to claim 8, characterized in that said at least one insulating resin coat layer is formed on the overall surface of the metal substrate including the inner walls of the through-holes, and has, at the circumferential edges formed by the intersection of the upper and the lower surfaces of said metal substrate and the inner walls of said through-holes, a thickness that is smaller than that on said upper and said lower surfaces of the metal substrate.

Claim 11

A baseboard for a printed circuit board according to claim 8, characterized in that said at least one insulating resin coat layer is formed on the overall surface of the metal substrate excluding the inner wall surfaces of the through-holes.

Claim 12

A baseboard for a printed circuit board according to claim 4, characterized in that said insulating, adhesive resin coat layer is provided in multiple layer system.

Claim 13

A baseboard for a printed circuit board according to claim 2, characterized in that the base metal is preliminarily coated, at least on the upper and the lower surface of the base metal, with an insulating coat layer.

Claim 14

A baseboard for a printed circuit board according to claim 4, characterized in that the base metal is preliminarily coated, at least on the upper and the lower surface of the base metal, with an insulating coat layer.

Claim 15

A baseboard for a printed circuit board produced by a method comprising dipping a metal substrate having through-holes in a solution of a resin in a solvent, which solution has a resin concentration of not more than 50% by weight and a viscosity of not more than 50 centipoises and taking the metal substrate out of said solution in the direction of at an angle of 90°±30° with respect to the axis of the through-holes of said metal substrate at a velocity of not more than 1,000 mm/min to form a resin coat layer covering the overall surface of the metal substrate and filling the through-holes and which, upon drying, forms a membrane over said holes which breaks and results in the formation of a coating on the inner wall surfaces of the through-holes and in the formation, at the circumferential edges formed by the intersection of the upper and lower surfaces of said metal substrate with the inner walls of said through-holes, of a coating having a thickness larger than the thickness of said coating on said upper and said lower surfaces of the metal substrate.

Claim 16

A baseboard for a printed circuit board produced by a method comprising dipping a metal substrate having through-holes in a solution of a resin in a solvent, which solution has a resin concentration of not more than 50% by weight and a viscosity of not more than 50 centipoises and taking the metal substrate out of said solution in the direction of at an angle of 90°±30° with respect to the axis of the through-holes of said metal substrate at a velocity of not more than 1,000 mm/min to form a resin coat layer covering the overall surface of the metal substrate and filling the through-holes and which, upon drying, forms a membrane over said holes which breaks and results in the formation of a coating on the inner wall surfaces of the through-holes and in the formation, at the circumferential edges formed by the intersection of the upper and lower surfaces of said metal substrate with the inner walls of said through-holes, of a coating having a thickness larger than the thickness of said coating on said upper and said lower surfaces of the metal substrate.

Claim 17

The baseboard of claim 14 wherein said resin is an insulating resin.

Claim 18

The baseboard of claim 14 wherein said resin is an adhesive resin.

Claim 19

The baseboard of claim 14 wherein said resin is an insulating adhesive resin.

Claim 20

The baseboard of claim 14 wherein, after said formation of the resin coating by dipping is effected, the metal substrate with its overall surface covered with said resin coat layer is further covered, at least on the upper and lower surfaces thereof, with a further resin coating.

Claim 21

The baseboard of claim 18 wherein said other resin coating is applied by dropping a solution of a resin in a solvent, which solution has a viscosity of not less than 400 centipoises, onto the surface of said metal substrate while moving said metal substrate in a horizontal direction at a velocity higher than that of the dropping of said solution.

Claim 22

The baseboard of claim 19 wherein the moving velocity of said metal substrate is 20 to 40% higher than the dropping velocity of said solution.

Claim 23

The baseboard of claim 19 wherein said other resin coating is applied by a curtain flow coating method.

Claim 24

The baseboard of claim 19 wherein said other resin coating is applied by an electrostatic powder coating method.

Claim 25

The baseboard of claim 14 wherein, before said formation of the resin coating by dipping is effected, the metal substrate having through-holes is covered, at least on the upper and the lower surfaces thereof, with a first resin coating.

Claim 26

The baseboard of claim 23 wherein said first resin coating is applied by dropping a solution of a resin in a solvent, which solution has a viscosity of not less than 400 centipoises, onto the surface of said metal substrate while moving said metal substrate in a horizontal direction at a velocity higher than that of the dropping of said solution.

Claim 27

The baseboard of claim 24 wherein the moving velocity of said metal substrate is 20 to 40% higher than the dropping velocity of said solution.

Claim 28

The baseboard of claim 24 wherein said other resin coating is applied by a curtain flow coating method.

Claim 29

The baseboard of claim 23 wherein said other resin coating is applied by an electrostatic powder coating method.

Claim 30

The baseboard of claim 14 wherein, before said formation of the resin coating by dipping is effected, a metal substrate without through-holes is covered, on the upper and the lower surfaces thereof, with a first resin coating and the coated substrate is subsequently perforated to form through-holes in a predetermined pattern therein.

Claim 31

The baseboard of claim 28 wherein said first resin coating is applied by a roll coating method.

Claim 32

The baseboard of claim 28 wherein, after said formation of the resin coating by the dipping is effected, the metal substrate with its overall surface covered with said resin coat layer is further covered, at least on the upper and the lower surfaces thereof, with a third resin coating.

Claim 33

The baseboard of claim 18 wherein the resin of said resin coating is an insulating resin and the resin of said further resin coating is an adhesive resin.

Claim 34

The baseboard of claim 18 wherein said resin of said resin coating is an insulating resin and the resin of said further resin coating is an insulating adhesive resin.

Claim 35

The baseboard of claim 14 wherein said formation of the resin coating by dipping is effected two or more times.

Claim 36

The baseboard of claim 18 wherein said formation of the resin coating by dipping is effected two or more times.

Claim 37

The baseboard of claim 23 wherein said formation of the resin coating by dipping is effected two or more times.

Claim 38

The baseboard of claim 28 wherein said formation of the resin coating by dipping is effected two or more times.

Claim 39

The baseboard of claim 30 wherein said formation of the resin coating by dipping is effected two or more times.

Claim 40

The baseboard of claim 18 wherein the formation of said further resin coating is also effected by said dipping.

Claim 41

The baseboard of claim 30 wherein the application of said third resin coating is also effected by said dipping.

Claim 42

The baseboard of claim 18 wherein said further resin coating is applied by an electrostatic coating method.