Laminated entry and exit material for drilling printed circuit boards
AssigneeR. E. Service Company, Inc.
InventorMark S. Frater
Life of this patent
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Abstract
A laminated entry and exit material for drilling planar sheets such as printed circuit boards having a metal foil layer bonded to a fibrous core layer with an adhesive containing a particulate lubricant such as graphite or polyethylene glycol and cold or hot pressed. A second metal layer is preferably bonded to the fibrous core layer. The core of one embodiment of the exit material includes a particulate lubricant such as graphite or polyethylene glycol incorporated in the core at the time of manufacture of the core. The circuit board is placed between the entry and exit materials. Drill friction and heat are reduced by the lubricants and the heat sink provided by the foil thereby extending the service life of a drill.
Claims13
A sheet laminate material for drilling a printed circuit board, comprising:
- a first metal sheet;
- a second metal sheet;
- and
- a fibrous core;
- said fibrous core coupled to said first metal sheet with a first adhesive layer;
- said fibrous core coupled to said second metal sheet with a second adhesive layer;
- wherein said adhesive layers contain a particulate lubricant, said lubricant comprising polyethylene glycol having a molecular weight ranging from approximately 600 to approximately 4,000.
A sheet laminate material for drilling a printed circuit board, comprising:
- a first substrate layer;
- a second substrate layer;
- and
- a fibrous core;
- said fibrous core coupled to said first substrate with a first adhesive layer;
- said fibrous core coupled to said second substrate with a second adhesive layer;
- wherein said adhesive layers contain a particulate lubricant, said lubricant comprising polyethylene glycol having a molecular weight ranging from approximately 600 to approximately 4,000.
Dependencies are inferred from the claim text.