Method of controlling hydrogen ion concentration by microcapsules

A method for controlling the hydrogen ion concentration of an aqueous acidic solution which comprises adding to the aqueous acidic solution an aqueous solution containing a dispersion of microcapsules prepared by encapsulating an alkali material with a polymer which is non-permeable prior to attack by acid, said polymer being swelled in an acid state only, the term "swelled" meaning the attacking of said polymer by said solution so that the microcapsule shell is swelled to increase the permeability thereof and thus permit part of the alkali within said microcapsule to be released into the solution to neutralize acid present.

A method for controlling the hydrogen ion concentration of an aqueous alkali solution which comprises adding to the aqueous alkali solution an aqueous solution containing a dispersion of microcapsules prepared by encapsulating an acid material with a polymer which is non-permeable prior to attack by alkali, said polymer being swelled in an alkali state only, the term "swelled" meaning the attacking of said polymer by said solution so that the microcapsule shell is swelled to increase the permeability thereof and thus permit part of the acid within said microcapsule to be released into the solution to neutralize alkali present, said polymer being cellulose acetate phthalate.

A method for controlling the hydrogen ion concentration of an aqueous alkali solution which comprises adding to the aqueous alkali solution an aqueous solution containing a dispersion of microcapsules prepared by encapsulating an acid material with a polymer which is nonpermeable prior to attack by alkali, said polymer being swelled in an alkali state only, the term "swelled" meaning the attacking of said polymer by said solution so that the microcapsule shell is swelled to increase the permeability thereof and thus permit part of the acid within said microcapsule to be released into the solution to neutralize alkali present, said polymer being a casein resin.

A method for controlling the hydrogen ion concentration of an aqueous acidic solution which comprises adding to the aqueous acidic solution an aqueous solution containing a dispersion of microcapsules prepared by encapsulating an alkali material with a polymer which is nonpermeable prior to attack by acid, said polymer being swelled in an acid state only, the term "swelled" meaning the attacking of said polymer by said solution so that the microcapsule shell is swelled to increase the permeability thereof and thus permit part of the alkali within said microcapsule to be released into the solution to neutralize acid present, said polymer being N,N-di-n-butylamino hydroxypropyl ether.

A method for controlling the hydrogen ion concentration of an aqueous alkali solution which comprises adding to the aqueous alkali solution an aqueous solution containing a dispersion of microcapsules prepared by encapsulating citric acid with a polymer which is nonpermeable prior to attack by alkali, said polymer being swelled in an alkali state only, the term "swelled" meaning the attacking of said polymer by said solution so that the microcapsule shell is swelled to increase the permeability thereof and thus permit part of the acid within said microcapsule to be released into the solution to neutralize alkali present, said polymer being cellulose acetate phthalate.

A method for controlling the hydrogen ion concentration of an aqueous alkali solution which comprises adding to the aqueous alkali solution an aqueous solution containing a dispersion of microcapsules prepared by encapsulating citric acid with a polymer which is non-permeable prior to attack by alkali, said polymer being swelled in an alkali state only, the term "swelled" meaning the attacking of said polymer by said solution so that the microcapsule shell is swelled to increase the permeability thereof and thus permit part of the acid within said microcapsule to be released into the solution to neutralize alkali present, said polymer being a casein resin.

A method for controlling the hydrogen ion concentration of an aqueous acidic solution which comprises adding to the aqueous acidic solution an aqueous solution containing a dispersion of microcapsules prepared by encapsulating an alkali material selected from the group consisting of sodium carbonate and sodium bicarbonate with a polymer which is nonpermeable prior to attack by acid, said polymer being swelled in an acid state only, the term "swelled" meaning the attacking of said polymer by said solution so that the microcapsule shell is swelled to increase the permeability thereof and thus permit part of the alkali within sid microcapsule to be released into the solution to neutralize acid present, said polymer being N,N-di-n-butylamino hydroxypropyl ether.