Purification process
AssigneeRohm and Haas Company
InventorsRichard J. Carey, James W. Thackeray
Life of this patent
Estimating the term…
Abstract
A process for the purification of an organic solution containing an acid labile material. The process comprises contact of the organic solution with a combination of a cation exchange resin and an anion exchange resin. The cation exchange resin has weak acidic groups to reduce attack on the acid labile material within the organic solution. The anion exchange resin preferably has hydroxide exchange groups. The combination of exchange resins yields counter-ions that form water in the solution treated upon contact with the solution with the exchange resin mixture.
Claims11
A method for removal of cationic and anionic contaminants from an organic solution of an acid catalyzed photoresist composition containing one or more acid labile components subject to reaction in the presence of a strong acid, said process comprising the steps of providing said organic solution containing said one or more acid labile components, providing a weak acid cation exchange resin having a pK.sub.a such that the weak acid exchange groups on said resin do not react with acid labile components of the photoresist, providing a strong base anion exchange resin, and contacting said organic solution with said cation exchange resin and said anion exchange resin for a time sufficient to remove essentially all dissolved contaminants from solution without causing reaction between said acid labile components of the photoresist composition and said cation exchange resin.
Dependencies are inferred from the claim text.