Patent EP0469470A1 successfully refreshed from Google Patents.
EP0469470A1
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Process for producing multilayered printed board
Assignee: Mitsubishi Gas Chemical Co Inc
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Filing: 1991-07-25
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Granted: —
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Expires: 2011-07-25
Abstract
Abstract A process for producing a multilayered printed circuit board which comprises using, as an intermediate layer, an inner-layer board obtained by chemically oxidizing the surface of a copper foil constituting an outermost layer of an inner-layer board having a printed circuit formed in the copper foil, thereby to form on the surface a finely roughened layer constituted by a copper oxide of a brown to black color, and then reducing the copper oxide constituting the finely roughened layer in an atmosphere in which a reducing gas is present.
Inventors
- 👤 Ando Kazuhiro
- 👤 Kawakami Takamasa
- 👤 Shouji Yasuhiro
- 👤 Tanaka c/o Mitsubishi Gas Chem. Comp. Inc. Yasuo
- 👤 Kanaoka c/o Mitsubishi Gas Chem. Co. Inc. Takeo
- 👤 Sayama c/o Mitsubishi Gas Chem. Comp. Inc. Norio
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-11-09 08:47
CPC Classifications
H; H05; H05K; H05K3/00; H05K3/46; H05K3/38; H05K3/382; H05K3/385; H05K2203/00; H05K2203/03; H05K2203/0315; H05K2203/11; H05K2203/1157; H05K3/4611
Claims Analysis
Total Claims: 14
Claim 1
Independent Claim
88 words
A process for producing a multilayered printed circuit board which comprises using, as an intermediate layer, an inner-layer board obtained by chemically oxidizing the surface of a copper foil constituting an outermost layer of an inner-layer board having a printed circuit formed in the copper foil, thereby to form on the surface a finely roughened layer constituted by a copper oxide of a brown to black color, and then reducing the copper oxide constituting the finely roughened layer in an atmosphere in which a reducing gas is present.
Claim 2
Dependent Claim
88 words
A process for producing a multilayered printed circuit board which comprises using, as an intermediate layer, an inner-layer board obtained by chemically oxidizing the surface of a copper foil constituting an outermost layer of an inner-layer board having a printed circuit formed in the copper foil, thereby to form on the surface a finely roughened layer constituted by a copper oxide of a brown to black color, and then reducing the copper oxide constituting the finely roughened layer in an atmosphere in which a reducing gas is present.
Claim 3
Dependent Claim
19 words
A process as claimed in claim 1, wherein said reducing gas is hydrogen, carbon monoxide, or a mixture thereof.
Claim 4
Dependent Claim
21 words
A process as claimed in claim 2, wherein the reduction is conducted at a temperature of from 100 to 160° C.
Claim 5
Dependent Claim
14 words
A process as claimed in claim 1, wherein said reducing gas is hydrazine gas.
Claim 6
Dependent Claim
20 words
A process as claimed in claim 4, wherein the pressure of said hydrazine gas is from 0.01 to 15 mmHg.
Claim 7
Dependent Claim
21 words
A process as claimed in claim 5, wherein the reduction is conducted at a temperature of from 60 to 140° C.
Claim 8
Dependent Claim
25 words
A process as claimed in claim 1, wherein a platinum group metal catalyst is fixed on the finely roughened layer constituted by a copper oxide.
Claim 9
Dependent Claim
16 words
A process as claimed in claim 7, wherein said platinum group metal catalyst is palladium (Pd).
Claim 10
Dependent Claim
139 words
A process for producing a multilayered printed circuit board which comprises chemically oxidizing the surface of a copper foil constituting an outermost layer of an inner-layer board having a printed circuit formed in the copper foil, thereby to form on the surface a finely roughened layer constituted by a copper oxide of a brown to black color, laminating the thus-treated inner-layer board as an intermediate layer with other laminating materials thereby to form a multilayered board, subjecting the multilayered board to the formation of through-holes, and thereafter reducing the copper oxide constituting the finely roughened layer on the copper foil in at least those parts of the inner-layer board which are close to the through-holes, said reduction being conducted during the period between said through-hole formation and electroless plating in an atmosphere in which a reducing gas is present.
Claim 11
Dependent Claim
139 words
A process for producing a multilayered printed circuit board which comprises chemically oxidizing the surface of a copper foil constituting an outermost layer of an inner-layer board having a printed circuit formed in the copper foil, thereby to form on the surface a finely roughened layer constituted by a copper oxide of a brown to black color, laminating the thus-treated inner-layer board as an intermediate layer with other laminating materials thereby to form a multilayered board, subjecting the multilayered board to the formation of through-holes, and thereafter reducing the copper oxide constituting the finely roughened layer on the copper foil in at least those parts of the inner-layer board which are close to the through-holes, said reduction being conducted during the period between said through-hole formation and electroless plating in an atmosphere in which a reducing gas is present.
Claim 12
Dependent Claim
31 words
A process as claimed in claim 9, wherein the treatment in an atmosphere in which a reducing gas is present is conducted during the period between desmear treatment and electroless plating.
Claim 13
Dependent Claim
19 words
A process as claimed in claim 9, wherein said reducing gas is hydrogen, carbon monoxide, or a mixture thereof.
Claim 14
Dependent Claim
14 words
A process as claimed in claim 9, wherein said reducing gas is hydrazine gas.
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