Abstract: A process of removing trace levels of metallic impurities from resist or photoresist component solutions by treating the resist or resist component solution with an aqueous solution of a water soluble oxidizer, such as hydrogen peroxide, then with an acidic aqueous solution, and then allowing organic and aqueous phases to form with said aqueous phase containing metallic impurities extracted from said organic phase and the organic phase containing said resist or resist component solution with reduced amount of trace metal impurities, and separating the two phases.

Abstract: 1. A process for preparing a purified solution of blocked polyhydroxystyrene resin in reaction/photoresist solvent, comprising the steps of:(1) forming an impure reaction solution comprising blocked polyhydroxystyrene resin and acidic catalyst in reaction/photoresist solvent;(2) adding amine, at least one hydrophilic solvent, at least one hydrophobic solvent and water to said impure reaction solution, thereby forming an aqueous phase comprising water, the hydrophilic solvent, and at least one salt of the amine and the acidic catalyst and an organic phase comprising the hydrophilic solvent, the hydrophobic solvent, the reaction/photoresist solvent and the blocked polyhydroxystyrene resin;(3) separating the aqueous phase from the organic phase; and(4) removing the hydrophilic solvent and the hydrophobic solvent from the organic phase, thereby forming a purified solution of blocked polyhydroxystyrene resin in reaction/photoresist solvent.

Abstract: A process for reducing trace levels of metallic impurities in cyclized polyisoprene resin is disclosed. The process reduces trace levels of metallic impurities in cyclized polyisoprene resin by washing an impure organic solvent/cyclized polyisoprene resin solution at least once with a heated aqueous acidic solution, and subsequently washing the resin at least once with heated water.

Abstract: A process of removing trace metal impurities from an impure resist component solution comprising the steps of:(1) forming an impure resist component solution containing trace amounts of dissolved metallic impurities, the resist component solvent selected from the group consisting of ethyl lactate, ethyl 3-ethoxypropionate, methyl 3-methoxypropionate, propylene glycol methyl ethyl acetate, or mixtures thereof;(2) contacting said impure resist component solution with a mixture of cyclohexane and isopropyl acetate and with an aqueous acidic solution for a sufficient amount of time to form a first two-phase reaction mixture comprising a first aqueous phase containing metallic impurities extracted from said impure resist component solution and a first organic phase containing said resist component solution with a reduced amount of trace metal impurities;(3) separating said first aqueous phase from said first organic phase;(4) contacting said first organic phase with a mixture of water and resist component solvent