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:
Dec. 05, 1995
Filed:
Jan. 17, 1995
Joseph J Sizensky, Seekonk, MA (US);
Thomas R Sarubbi, Providence, RI (US);
Medhat A Toukhy, Barrington, RI (US);
OCG Microelectronic Materials, Inc., West Paterson, NJ (US);
Abstract
A phenolic novolak composition prepared by a process comprising the steps of: (1) reacting a first phenolic monomer comprising a major portion of at least one trifunctional phenolic monomer with a first aldehyde source in the absence of a catalyst at a reaction temperature from about 100.degree. C. to about 200.degree. C. and at a reaction pressure of about 2 to about 15 atmospheres to form a phenolic oligomer having a weight average molecular weight from about 500 to about 2,000, having ortho--ortho bonding of about 55% to about 75% of the methylene bonds between the phenolic moieties; and having a time to clear of less than 125 seconds per micron; wherein the mole ratio of said first aldehyde source to said first phenolic monomer is from about 0.3:1.0 to about 0.55:1.0; and (2) then reacting said oligomer with an optional second phenolic source and a second aldehyde source at a temperature from about 80.degree. C. to about 150.degree. C. to form a phenolic novolak having a weight average molecular weight of 3,000 to 40,000, having ortho--ortho bonding of between 50% and 70% of the methylene bonds between the phenolic moieties, and having a time to clear of at least 20 seconds per micron; wherein the mole ratio of said second aldehyde source to said total phenolic moieties is less than about 0.8:1.0.