The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Sep. 23, 1997
Filed:
May. 16, 1995
Applicant:
Inventors:
Robert J Sanville, Jr, Northfield, NH (US);
Carl P Kernander, Lee, NH (US);
Assignee:
Polyclad Laminates, Inc., West Franklin, NH (US);
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
B32B / ; B32B / ; D02G / ; H05K / ;
U.S. Cl.
CPC ...
428323 ; 4283202 ; 428375 ; 428391 ; 428340 ; 428446 ; 428447 ; 428209 ; 428901 ; 174256 ;
Abstract
This invention involves a prepreg composition and procedure for use in forming printed circuit boards with reduced and uniform dielectric constant, improved thermal expansion characteristics, and uniform appearance. The prepreg composite is a resin impregnated substrate and has a reduced dielectric constant as low as 3.5. It contains 5-30% by resin volume of hollow inorganic microsphere filler whose diameters are less than 40 micrometers, and the uniform distribution of the hollow inorganic microspheres is controlled by the presence of hydrophobic fumed silica or other similar flow modifier.