Process for plating selected metal areas

• US 4,294,669 A
• Filed: 09/08/1980
• Issued: 10/13/1981
• Est. Priority Date: 09/08/1980
• Status: Expired due to Term

• Current Assignee: GTE Products Corporation
• Original Assignee: GTE Products Corporation
• Inventors: Lincoln, Howard P., Reddinger, Donald M.
• Primary Examiner(s): Lawrence, Evan K.
• Application Number:
  US06/185,091
• Time in Patent Office: 400 Days
• Field of Search: 204/15, 204/17, 204/18.1, 204/224 R
• US Class Current: 205/135
• CPC Class Codes: C25D 5/022 using masking means
• CPC Class Codes: H05K 3/241 characterised by the electroplating method; means therefor, e.g. baths or apparatus
• CPC Class Codes: H05K 3/243 characterised by selective plating, e.g. for finish plating of pads selective plating for making the circuit pattern H05K3/108, H05K3/182

Abstract

An apertured plating mask having a polyurethane layer thereon to enhance the sealing thereof to a metal has been provided. The plating mask has a substantially smooth layer for contact with a metal as well as a polyurethane covering of the inner perimeter of the apertures of the plating mask whereby definition of selected areas for plating is enhanced. The apertured plating mask is fabricated by a unique molding process wherein a fabricated mask blank is positioned in a mold member, polyurethane is poured through and over the mask blank, cured and treated in the mold member to provide the apertured mask with a polyurethane layer having a substantially smooth surface. Also, a process and apparatus are provided for plating selected areas of a metal wherein a metal is contacted on one surface with a rubber-covered rigid plate and on the opposite surface with an apertured plating mask having a layer of polyurethane with a smooth surface thereon. A plating solution is applied through the apertures of the plating mask to selected areas of the metal as defined by the polyurethane and energized to provide the desired plated area.

Claims

1. In a process for plating selected areas of a metal wherein a rigid plate covered with a resilient material is placed in contact with one surface of the metal and a plating solution is energized and applied to the selected areas of the opposite surface of the metal, the improvement comprising the steps of contacting the opposite surface of the metal with an apertured mask comprising a mask blank having a plurality of apertures and having a layer of polyurethane on one surface for forming a seal with said metal, a layer of polyurethane affixed to the inner periphery of the apertures of said apertured mask, and a layer of polyurethane in a recessed portion of an opposite surface of said apertured mask blank surrounding each one of said apertures and applying said plating solution to said selected areas of said metal through said apertures of said apertured mask.

2. The process of claim 1 including the step of treating said layer of polyurethane on said apertured mask prior to said contracting of the metal with the mask to provide a substantially flat polyurethane surface contacting said metal.

3. The process of claim 1 wherein said layer of polyurethane on said one surface of said apertured mask blank is treated prior to said contacting of the metal with the mask to provide a substantially flat surface layer of polyurethane having a thickness in the range of about 0.020 to 0.080 inches.