US PATENT SUBCLASS 162 / 89
.~.~.~.~ Alkali metal, ammoninum, alkaline earth metal or magnesium hydroxide or carbonate in at least one stage

Current as of: June, 1999
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162 /   HD   PAPER MAKING AND FIBER LIBERATION

1  DF  PROCESSES OF CHEMICAL LIBERATION, RECOVERY OR PURIFICATION OF NATURAL CELLULOSE OR FIBROUS MATERIAL {33}
70  DF  .~ Treatment with particular chemical {9}
87  DF  .~.~ Chlorine containing {1}
88  DF  .~.~.~ Plural diverse stage treatments {1}
89.~.~.~.~ Alkali metal, ammoninum, alkaline earth metal or magnesium hydroxide or carbonate in at least one stage

DEFINITION

Classification: 162/89

(under subclass 88) Processes in which a hydroxide or carbonate of an alkali metal, ammonium, an alkaline earth metal or magnesium is employed in at least one of the separate treatments.

(1) Note. The alkali metals are lithium, sodium, potassium, rubidium and cesium.

(2) Note. The alkaline earth metals are calcium, strontium and barium.