Method and apparatus for preparing conductive screened through holes employing metallic plated polymer thick films

Claim 2

In the method of preparing conductive bridges to electrically couple discrete electrical conductors arranged on opposed surfaces of a common substrate with the conductive bridge extending along and through the walls of a bore formed through the common substrate as a continuation of the respective opposed electrical conductors, said method comprising the steps of: (a) preparing a screen layout of the circuit pattern to be formed and mounting said screen layout under tension for use in printing a delineated curable liquid conductive ink coating defining the said circuit pattern to be formed upon the substrate surface; (b) preparing a supply web of a generally impervious flexible substrate to receive said circuit pattern and with bores being formed therein to accommodate electrical interconnects between circuit patterns to be formed on the opposed major surfaces thereof; (c) superimposing said flexible substrate upon a generally porous non-woven flexible vacuum diffusing carrier web pervious to air but impervious to said curable liquid conductive ink for simultaneous passage with said substrate as a web pair through a substrate printing zone; (d) passing said superposed substrate vacuum diffusing carrier web pair along a path within a substrate printing zone wherein said web pair traverses the surface of a printing bed plater with the printing bed having an outer surface enclosing a hollow core and with a plurality of bores formed through said outer surface to provide a perforated printing surface, moving said printing bed plate surface relative to a screen print layout while carrying said web pair thereover; (e) coupling the hollow core of said printing bed to a source of vacuum; (f) applying a layer of said curable liquid conductive ink coating upon the surface of said flexible substrate through said screen layout while simultaneously applying vacuum to the hollow core of said printing bed and through the bores formed through the annular wall thereof and through said air-pervious vacuum diffusing carrier web.

Claim 3

The method as defined in claim 1 being particularly characterized in that said printing bed is a printing cylinder and said substrate vacuum diffusing carrier web is trained across the surface of printing cylinder for less than approximately 180 degrees of arc.

Claim 4

The method as defined in claim 1 being particularly characterized in that said screen layout is moved linearly in synchronism with the rotatable arcuate movement of the surface of said printing cylinder.

Claim 5

The method as defined in claim 3 being particularly characterized in that said screen layout is moved linearly along a plane substantially tangent to the surface of said printing cylinder.

Claim 6

Apparatus for the preparation of conductive bridges to electrically coupled discrete electrical conductors arranged on opposed surfaces of a common substrate with the conductive bridge extending along and through the walls of a bore formed through the common substrate as a continuation of the respective opposed electrical conductors, said apparatus comprising: (a) printing screen retaining means arranged to support a screen print layout for use in printing a delineated circuit pattern with curable liquid conductive ink upon a substrate surface, said printing screen retaining means including mounting means for guidably maintaining said screen print layout in operative disposition within a printing station; (b) a printing station for receiving a substrate to be printed, and means for applying a layer of a curable liquid conductive ink upon selected regions of the surface of a substrate positioned within said printing station; (c) means for guidably moving a supply web of a generally impervious flexible substrate through said printing station to receive said circuit pattern in the form of a layer of a curable liquid conductive ink and with bores being formed therein to accommodate electrical interconnects between circuit patterns to be formed on the opposed major surfaces of said substrate; (d) means for guidably moving a generally porous, non-woven flexible vacuum diffusing carrier web pervious to air but impervious to said curable liquid conductive ink for simultaneous passage with said substrate as a web apir through said printing station; (e) said printing station including a printing cylinder having an outer annular wall surrounding a hollow core and with a plurality of bores formed through said annular wall to provide a perforated cylindrical surface, mounting means for said printing cylinder arranged to rotatably support said printing cylinder for axial rotation within said printing station in registration with and in synchronism with said printing screen; (f) means for rotating said printing cylinder at a rate synchronized with the lineal movement of said superposed web pair through said printing station; (g) means coupling the hollow core of said printing cylinder to a source of vacuum; and (h) means for applying a layer of said curable liquid conductive ink coating upon the surface of said flexible substrate through said screen layout while simultaneously applying vacuum to the hollow core of said printing cylinder and through the bores formed in the annular wall thereof and through said air-pervious vacuum diffusing carrier web.

Claim 7

Apparatus for the preparation of conductive bridges to electrically coupled discrete electrical conductors arranged on opposed surfaces of a common substrate with the conductive bridge extending along and through the walls of a bore formed through the common substrate as a continuation of the respective opposed electrical conductors, said apparatus comprising: (a) printing screen retaining means arranged to support a screen print layout for use in printing a delineated circuit pattern with curable liquid conductive ink upon a substrate surface, said printing screen retaining means including mounting means for guidably maintaining said screen print layout in operative disposition within a printing station; (b) a printing station for receiving a substrate to be printed, and means for applying a layer of a curable liquid conductive ink upon selected regions of the surface of a substrate positioned within said printing station; (c) means for guidably moving a supply web of a generally impervious flexible substrate through said printing station to receive said circuit pattern in the form of a layer of a curable liquid conductive ink and with bores being formed therein to accommodate electrical interconnects between circuit patterns to be formed on the opposed major surfaces of said substrate; (d) means for guidably moving a generally porous, non-woven flexible vacuum diffusing carrier web pervious to air but impervious to said curable liquid conductive ink for simultaneous passage with said substrate as a web apir through said printing station; (e) said printing station including a printing cylinder having an outer annular wall surrounding a hollow core and with a plurality of bores formed through said annular wall to provide a perforated cylindrical surface, mounting means for said printing cylinder arranged to rotatably support said printing cylinder for axial rotation within said printing station in registration with and in synchronism with said printing screen; (f) means for rotating said printing cylinder at a rate synchronized with the lineal movement of said superposed web pair through said printing station; (g) means coupling the hollow core of said printing cylinder to a source of vacuum; and (h) means for applying a layer of said curable liquid conductive ink coating upon the surface of said flexible substrate through said screen layout while simultaneously applying vacuum to the hollow core of said printing cylinder and through the bores formed in the annular wall thereof and through said air-pervious vacuum diffusing carrier web.

Claim 8

The apparatus for preparation of conductive bridges to electrically coupled discrete electrical conductors as defined in claim 5 being particularly characterized in that said means for guiding the web pair are disposed to carry the said pair along a path over said printing cylinder wherein said pair is firmly draped across approximately 115 degrees of arc of the periphery of said printing cylinder.

Claim 9

The apparatus for preparation of conductive bridges to electrically coupled discrete electrical conductors as defined in claim 5 being particularly characterized in that said perforated surface comprises uniformly spaced circular holes of substantially uniform diameter and wherein said perforations are comprise between about 1% and 15% open, balance annular wall surface.

Claim 10

The apparatus for preparation of conductive bridges to electrically coupled discrete electrical conductors as defined in claim 7 being particularly characterized in that said holes are less than about 0.080 inch in diameter.

Claim 11

The apparatus for preparation of conductive bridges to electrically coupled discrete electrical conductors as defined in claim 5 being particularly characterized in that said screen print layout, substrate and diffusing layers are maintained in registered alignment through said printing station.

Claim 12

The apparatus for preparation of conductive bridges to electrically coupled discrete electrical conductors as defined in claim 5 being particularly characterized in that said printing screen retaining means moves linearly along a reciprocating path in synchronism with the rotation of said printing cylinder.

Claim 13

The apparatus for preparation of conductive bridges to electrically coupled discrete electrical conductors as defined in claim 5 being particularly characterized in that said curable liquid ink has a viscosity of between about 25,000 and 75,000 centipoises.

Claim 14

The apparatus for preparation of conductive bridges to electrically coupled discrete electrical conductors as defined in claim 11 being particularly characterized in that said porous medium is a filter paper of a thickness ranging from between about 5 mils and 8 mils, and a weight of about 1.28 ounces per square yard.

Claim 15

The apparatus for preparation of conductive bridges to electrically coupled discrete electrical conductors as defined in claim 5 being particularly characterized in that said means for guidingly moving said flexible substrate web includes means for maintaining a substantially constant tension on the web through the printing station.

Claim 16

In the method of preparing conductive bridges through bores formed in a substrate to electrically couple discrete electrical conductors arranged on different surfaces, with the conductive bridge extending along and through walls of a bore formed through the substrate as a continuation of the respective electrical conductors, said method comprising the steps of: (a) preparing a screen layout of the circuit pattern to be formed and mounting said screen layout under tension for use in printing a delineated curable liquid conductive ink coating defining the said circuit pattern to be formed upon the substrate surface; (b) preparing a supply web of a generally impervious flexible substrate to receive said circuit pattern on one surface of said flexible substrate and with bores being formed therein to accommodate electrical interconnects between the circuit patterns to be formed on said one surface of said flexible substrate and a circuit pattern disposed on a surface different from that of said flexible substrate surface; (c) superimposing said flexible substrate upon a generally porous non-woven flexible vacuum diffusing carrier web pervious to air but impervious to said curable liquid conductive ink for simultaneous passage with said substrate as a web pair through a substrate printing zone; (d) passing said superposed substrate vacuum diffusing carrier web pair along a path within a substrate printing zone wherein said web pair traverses at least a portion of the arcuate periphery of a printing cylinder having an outer annular wall surrounding a hollow core and with a plurality of bores formed through said annular wall to provide a perforated cylindrical surface, rotating said printing cylinder while carrying said web pair thereover at a peripheral rate of speed substantially equal to the lineal rate of speed of said superposed pair; (e) coupling the hollow core of said printing cylinder to a source of vacuum; (f) applying a layer of said curable liquid conductive ink coating upon the surface of said flexible substrate through said screen layout while simultaneously applying vacuum to the hollow core of said printing cylinder and through the bores formed through the annular wall thereof and through said air-pervious vacuum diffusing carrier web.

Claim 17

In the method of preparing conductive bridges through bores formed in a substrate to electrically couple discrete electrical conductors arranged on different surfaces, with the conductive bridge extending along and through walls of a bore formed through the substrate as a continuation of the respective electrical conductors, said method comprising the steps of: (a) preparing a screen layout of the circuit pattern to be formed and mounting said screen layout under tension for use in printing a delineated curable liquid conductive ink coating defining the said circuit pattern to be formed upon the substrate surface; (b) preparing a supply web of a generally impervious flexible substrate to receive said circuit pattern on one surface of said flexible substrate and with bores being formed therein to accommodate electrical interconnects between the circuit patterns to be formed on said one surface of said flexible substrate and a circuit pattern disposed on a surface different from that of said flexible substrate surface; (c) superimposing said flexible substrate upon a generally porous non-woven flexible vacuum diffusing carrier web pervious to air but impervious to said curable liquid conductive ink for simultaneous passage with said substrate as a web pair through a substrate printing zone; (d) passing said superposed substrate vacuum diffusing carrier web pair along a path within a substrate printing zone wherein said web pair traverses at least a portion of the arcuate periphery of a printing cylinder having an outer annular wall surrounding a hollow core and with a plurality of bores formed through said annular wall to provide a perforated cylindrical surface, rotating said printing cylinder while carrying said web pair thereover at a peripheral rate of speed substantially equal to the lineal rate of speed of said superposed pair; (e) coupling the hollow core of said printing cylinder to a source of vacuum; (f) applying a layer of said curable liquid conductive ink coating upon the surface of said flexible substrate through said screen layout while simultaneously applying vacuum to the hollow core of said printing cylinder and through the bores formed through the annular wall thereof and through said air-pervious vacuum diffusing carrier web.

Claim 18

In the method of preparing conductive bridges to electrically couple discrete electrical conductors arranged on opposed surfaces of a common substrate with the conductive bridge extending along and through the walls of a bore formed through the common substrate as a continuation of the respective opposed electrical conductors, said method comprising the steps of: (a) preparing a screen layout of the circuit pattern to be formed and mounting said screen layout under tension for use in printing a delineated curable liquid conductive ink coating defining the said circuit pattern to be formed upon the substrate surface; (b) preparing a supply web of a generally impervious flexible substrate to receive said circuit pattern and with bores being formed therein to accommodate electrical interconnects between circuit patterns to be formed on the opposed major surfaces thereof; (c) superimposing said flexible substrate upon a generally porous non-woven flexible vacuum diffusing carrier web pervious to air but impervious to said curable liquid conductive ink for simultaneous passage with said substrate as a web pair through a substrate printing zone; (d) passing said superposed substrate vacuum diffusing carrier web pair along a path within a substrate printing zone wherein said web pair is carried across a porous printing surface having an outer web pair contacting surface to provide a perforated web contacting surface, moving said porous printing surface in synchronism with the lineal movement of said superposed web pair so as to eliminate relative movement therebetween; (e) coupling the hollow core of said porous printing surface to a source of vacuum; (f) applying a layer of said curable liquid conductive ink coating upon the surface of said flexible substrate through said screen layout while simultaneously applying vacuum to the hollow core of said porous printing surface and through the bores formed through the annular wall thereof and through said air-pervious vacuum diffusing carrier web.

Claim 19

In the method of preparing conductive bridges to electrically couple discrete electrical conductors arranged on opposed surfaces of a common substrate with the conductive bridge extending along and through the walls of a bore formed through the common substrate as a continuation of the respective opposed electrical conductors, said method comprising the steps of: (a) preparing a screen layout of the circuit pattern to be formed and mounting said screen layout under tension for use in printing a delineated curable liquid conductive ink coating defining the said circuit pattern to be formed upon the substrate surface; (b) preparing a supply web of a generally impervious flexible substrate to receive said circuit pattern and with bores being formed therein to accommodate electrical interconnects between circuit patterns to be formed on the opposed major surfaces thereof; (c) superimposing said flexible substrate upon a generally porous non-woven flexible vacuum diffusing carrier web pervious to air but impervious to said curable liquid conductive ink for simultaneous passage with said substrate as a web pair through a substrate printing zone; (d) passing said superposed substrate vacuum diffusing carrier web pair along a path within a substrate printing zone wherein said web pair is carried across a porous printing surface having an outer web pair contacting surface to provide a perforated web contacting surface, moving said porous printing surface in synchronism with the lineal movement of said superposed web pair so as to eliminate relative movement therebetween; (e) coupling the hollow core of said porous printing surface to a source of vacuum; (f) applying a layer of said curable liquid conductive ink coating upon the surface of said flexible substrate through said screen layout while simultaneously applying vacuum to the hollow core of said porous printing surface and through the bores formed through the annular wall thereof and through said air-pervious vacuum diffusing carrier web.

Claim 20

In the method of preparing conductive bridges to electrically couple discrete electrical conductors arranged in discrete layers in multiple layer form on opposed surfaces of a common substrate with the conductive bridge extending along and through the walls of a bore formed through the common substrate as a continuation of the respective opposed electrical conductors disposed adjacent the conductors bonded to the substrate surface, said method comprising the steps of: (a) preparing a screen layout of the circuit pattern to be formed and mounting said screen layout under tension for use in printing a delineated curable liquid conductive ink coating defining the said circuit pattern to be formed upon the substrate surface; (b) preparing a supply web of a generally impervious flexible substrate to receive said circuit pattern and with bores being formed therein to accommodate electrical interconnects between circuit patterns to be formed on the opposed major surfaces thereof; (c) superimposing said flexible substrate upon a generally porous non-woven flexible vacuum diffusing carrier web pervious to air but impervious to said curable liquid conductive ink for simultaneous passage with said substrate as a web pair through a substrate printing zone; (d) passing said superposed substrate vacuum diffusing carrier web pair along a path within a substrate printing zone wherein said web pair traverses at least a portion of the arcuate periphery of a printing cylinder having an outer annular wall surrounding a hollow core and with a plurality of bores formed through said annular wall to provide a perforated cylindrical surface, rotating said printing cylinder while carrying said web pair thereover at a peripheral rate of speed substantially equal to the lineal rate of speed of said superposed pair; (e) coupling the hollow core of said printing cylinder to a source of vacuum; (f) applying a layer of said curable liquid conductive ink coating upon the surface of said flexible substrate through said screen layout while simultaneously applying vacuum to the hollow core of said printing cylinder and through the bores formed through the annular wall thereof and through said air-pervious vacuum diffusing carrier web; (g) curing said liquid conductive ink coating; (h) repeating steps (c) through (g) to form layers of cured liquid conductive ink coatings on both opposed major surfaces of said substrate; (i) plating a layer of a conductive metal onto the exposed surfaces of said cured conductive ink coating; (j) applying a layer of a dielectric ink in a delineated pattern to the surfaces of said conductive metal layer and thereafter curing said dielectric ink conductive metallic layer; (k) applying a second layer of a curable liquid conductive ink upon the surface of said cured dielectric layer, and thereafter curing said second curable liquid conductive ink layer; and (l) plating a layer of a conductive metal onto the exposed surfaces of said second cured conductive ink coating layer.

Claim 21

In the method of preparing conductive bridges to electrically couple discrete electrical conductors arranged in discrete layers in multiple layer form on opposed surfaces of a common substrate with the conductive bridge extending along and through the walls of a bore formed through the common substrate as a continuation of the respective opposed electrical conductors disposed adjacent the conductors bonded to the substrate surface, said method comprising the steps of: (a) preparing a screen layout of the circuit pattern to be formed and mounting said screen layout under tension for use in printing a delineated curable liquid conductive ink coating defining the said circuit pattern to be formed upon the substrate surface; (b) preparing a supply web of a generally impervious flexible substrate to receive said circuit pattern and with bores being formed therein to accommodate electrical interconnects between circuit patterns to be formed on the opposed major surfaces thereof; (c) superimposing said flexible substrate upon a generally porous non-woven flexible vacuum diffusing carrier web pervious to air but impervious to said curable liquid conductive ink for simultaneous passage with said substrate as a web pair through a substrate printing zone; (d) passing said superposed substrate vacuum diffusing carrier web pair along a path within a substrate printing zone wherein said web pair traverses at least a portion of the arcuate periphery of a printing cylinder having an outer annular wall surrounding a hollow core and with a plurality of bores formed through said annular wall to provide a perforated cylindrical surface, rotating said printing cylinder while carrying said web pair thereover at a peripheral rate of speed substantially equal to the lineal rate of speed of said superposed pair; (e) coupling the hollow core of said printing cylinder to a source of vacuum; (f) applying a layer of said curable liquid conductive ink coating upon the surface of said flexible substrate through said screen layout while simultaneously applying vacuum to the hollow core of said printing cylinder and through the bores formed through the annular wall thereof and through said air-pervious vacuum diffusing carrier web; (g) curing said liquid conductive ink coating; (h) repeating steps (c) through (g) to form layers of cured liquid conductive ink coatings on both opposed major surfaces of said substrate; (i) plating a layer of a conductive metal onto the exposed surfaces of said cured conductive ink coating; (j) applying a layer of a dielectric ink in a delineated pattern to the surfaces of said conductive metal layer and thereafter curing said dielectric ink conductive metallic layer; (k) applying a second layer of a curable liquid conductive ink upon the surface of said cured dielectric layer, and thereafter curing said second curable liquid conductive ink layer; and (l) plating a layer of a conductive metal onto the exposed surfaces of said second cured conductive ink coating layer.

Claim 22

The method as described in claim 16 being particularly characterized in that said plated conductive metallic layers are selected from the group consisting of copper and nickel.

Claim 23

In the method of preparing conductive bridges through bores formed in a substrate to electrically coupled discrete electrical conductor layers arranged on opposed surfaces of a common substrate, with the conductive bridge extending along and through walls of a bore formed through the substrate as a continuation of the respective electrical conductors, said method comprising the steps of: (a) preparing a screen layout of the circuit pattern to be formed and mounting said screen layout under tension for use in printing a delineated curable liquid conductive ink coating defining the said circuit pattern to be formed upon the substrate surface; (b) preparing a supply web of a generally impervious flexible substrate to receive said circuit pattern on one surface of said flexible substrate and with bores being formed therein to accommodate electrical interconnects between the circuit patterns to be formed on said one surface of said flexible substrate and a circuit pattern disposed on a surface different from that of said flexible substrate surface; (c) superimposing said flexible substrate upon a generally porous non-woven flexible vacuum diffusing carrier web pervious to air but impervious to said curable liquid conductive ink for simultaneous passage with said substrate as a web pair through a substrate printing zone; (d) passing said superposed substrate vacuum diffusing carrier web pair along a path within a substrate printing zone where said web pair traverses at least a portion of the arcuate periphery of a printing cylinder having an outer annular wall surrounding a hollow core and with a plurality of bores formed through said annular wall to provide a perforated cylindrical surface, rotating said printing cylinder while carrying said web pair thereover at a peripheral rate of speed substantially equal to the lineal rate of speed of said superposed pair; (e) coupling the hollow core of said printing cylinder to a source of vacuum; (f) applying a first layer of said curable liquid conductive ink coating upon one surface of said flexible substrate through said screen layout while simultaneously applying vacuum to the hollow core of said printing cylinder and through the bores formed through the annular wall thereof and through said air-pervious vacuum diffusing carrier web; (g) curing said liquid conductive ink coating; (h) repeating steps (a) through (g) to form a continuation of said first layer of said curable liquid conductive ink coating upon the opposed surface of said flexible substrate so as to provide cured liquid conductive ink coatings on both opposed major surfaces of said substrate; (i) plating a layer of a conductive metal to the exposed surfaces of said cured conductive ink coating; (j) applying a layer of a dielectric ink in a delineated pattern to the surface of said conductive metallic layer and thereafter curing said dielectric ink layer; (k) applying a second layer of a curable liquid conductive ink upon the surface of said cured dielectric layer, and thereafter curing said second curable liquid conductive ink layer; and (l) plating a second layer of a conductive metal to the exposed surfaces of said second cured conductive ink coating layer.

Claim 24

In the method of preparing conductive bridges through bores formed in a substrate to electrically coupled discrete electrical conductor layers arranged on opposed surfaces of a common substrate, with the conductive bridge extending along and through walls of a bore formed through the substrate as a continuation of the respective electrical conductors, said method comprising the steps of: (a) preparing a screen layout of the circuit pattern to be formed and mounting said screen layout under tension for use in printing a delineated curable liquid conductive ink coating defining the said circuit pattern to be formed upon the substrate surface; (b) preparing a supply web of a generally impervious flexible substrate to receive said circuit pattern on one surface of said flexible substrate and with bores being formed therein to accommodate electrical interconnects between the circuit patterns to be formed on said one surface of said flexible substrate and a circuit pattern disposed on a surface different from that of said flexible substrate surface; (c) superimposing said flexible substrate upon a generally porous non-woven flexible vacuum diffusing carrier web pervious to air but impervious to said curable liquid conductive ink for simultaneous passage with said substrate as a web pair through a substrate printing zone; (d) passing said superposed substrate vacuum diffusing carrier web pair along a path within a substrate printing zone where said web pair traverses at least a portion of the arcuate periphery of a printing cylinder having an outer annular wall surrounding a hollow core and with a plurality of bores formed through said annular wall to provide a perforated cylindrical surface, rotating said printing cylinder while carrying said web pair thereover at a peripheral rate of speed substantially equal to the lineal rate of speed of said superposed pair; (e) coupling the hollow core of said printing cylinder to a source of vacuum; (f) applying a first layer of said curable liquid conductive ink coating upon one surface of said flexible substrate through said screen layout while simultaneously applying vacuum to the hollow core of said printing cylinder and through the bores formed through the annular wall thereof and through said air-pervious vacuum diffusing carrier web; (g) curing said liquid conductive ink coating; (h) repeating steps (a) through (g) to form a continuation of said first layer of said curable liquid conductive ink coating upon the opposed surface of said flexible substrate so as to provide cured liquid conductive ink coatings on both opposed major surfaces of said substrate; (i) plating a layer of a conductive metal to the exposed surfaces of said cured conductive ink coating; (j) applying a layer of a dielectric ink in a delineated pattern to the surface of said conductive metallic layer and thereafter curing said dielectric ink layer; (k) applying a second layer of a curable liquid conductive ink upon the surface of said cured dielectric layer, and thereafter curing said second curable liquid conductive ink layer; and (l) plating a second layer of a conductive metal to the exposed surfaces of said second cured conductive ink coating layer.

Claim 25

The method as described in claim 18 being particularly characterized in that said plated conductive metallic layer is selected from the group consisting of copper and nickel.

Claim 26

The method as defined in claim 19 wherein siad layers of conductive metal are plated in an electroplating operation.