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EP0071872B1 Expired / Lapsed EP ⏱️ 0.0 years remaining

Method of detecting and analyzing flaws in a printed circuit board laminate

Assignee: International Business Machines Corp
•
Filing: 1982-07-27
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Granted: 1985-12-27
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Expires: 2002-07-27
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Abstract

No abstract record available.

Inventors

  • 👤 James Rusell Bupp
  • 👤 Lawrence Richard Maier

Bibliographic Details

Application Number —
Jurisdiction EP
Data Source google_patents
Last Synchronized 2026-11-06 10:51
CPC Classifications
G; G01; G01N; G01N21/00; G01N21/84; G01N21/88; G01N21/91; H; H05; H05K; H05K1/00; H05K1/02; H05K1/0266; H05K1/0269; H05K2203/00; H05K2203/02; H05K2203/0228; H05K2203/16; H05K2203/161; H05K3/00; H05K3/0011; H05K3/0044; H05K3/0052; H05K3/0055

Claims Analysis

Total Claims: 5
Claim 1
Independent Claim 165 words
A method of detecting and analyzing flaws in a printed circuit board laminate having metallized circuit lines and lands and drilled holes, characterized by the following steps: applying a penetrating solution containing a UV fluorescing dye to said circuit board laminate to fill drilled holes and flaws therein, said penetrating solution being capable of being polymerized; removing excess penetrating solution from the drilled holes and the surface of said circuit board laminate; curing the pentrating solution remaining in the flaws into an insoluble solid; cross-sectioning the circuit board laminate to provide at least one sample carrying the cured solution; encapsulating the sample in a clear epoxy; grinding and polishing said encapsulated sample to provide a surface to be examined; examining said surface under UV light; and photographing said surface to be examined under both UV light and regular light to make a record showing the nature and location of the flaws which fluoresce and also the metallized circuit lines and lands which do not fluoresce.
Claim 2
Independent Claim 165 words
A method of detecting and analyzing flaws in a printed circuit board laminate having metallized circuit lines and lands and drilled holes, characterized by the following steps: applying a penetrating solution containing a UV fluorescing dye to said circuit board laminate to fill drilled holes and flaws therein, said penetrating solution being capable of being polymerized; removing excess penetrating solution from the drilled holes and the surface of said circuit board laminate; curing the pentrating solution remaining in the flaws into an insoluble solid; cross-sectioning the circuit board laminate to provide at least one sample carrying the cured solution; encapsulating the sample in a clear epoxy; grinding and polishing said encapsulated sample to provide a surface to be examined; examining said surface under UV light; and photographing said surface to be examined under both UV light and regular light to make a record showing the nature and location of the flaws which fluoresce and also the metallized circuit lines and lands which do not fluoresce.
Claim 3
Dependent Claim 24 words
The method of claim 1, wherein the penetrating solution is stable in the presence of oxygen and is polymerizable in the absence of oxygen.
Claim 4
Dependent Claim 49 words
The method of claim 1, wherein said penetrating solution contains, in percentage by weight, about 70% of an anaerobic monomer, about 25% of a diluent, about 2% of an initiator, about 1% of an inhibitor, and about 2% total of a fluorescing dye, a nonionic surfactant, and an accelerator.
Claim 5
Dependent Claim 77 words
The method of claim 1, wherein said penetrating solution contains, in percentage by weight, about 70% of triethylene glycol dimethacrylate, about 25% of lauryl methacrylate, about 2% of cumene hydroperoxide, about 1% of benzoquinone, and about 2% total of a fluorescent dye being yellow in visible light and giving off a bright yellow-green light when irradiated with long wave length UV-light, a nonionic surface active agent consisting of an ethoxylated nonyl or octyl phenol and copper octonate.

References Cited (Backward Citations)

US3543570A Cited
USRE26888E Cited
US4237379A Cited

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