Method of staining slides and staining solutions therefor

Claim 1

THE METHOD OF STAINING ANIMAL-TISSUE FOR MICROSCOPIC EXAMINATION, COMPRISING APPLYING TO THE TISSUE A SOLUTION OF A STAINING MEDIUM FORMED BY OXIDIZING HEMATOXYLIN, A MORDANT FOR SAID STAINING MEDIUM, SAID STAINING MEDIUM AND MORDANT BEING PRESENT IN THE SOLUTION IN EQUIVALENT CHEMICAL COMBINING WEIGHTS OF THE STAINING MEDIUM AND MORDANT, RESPECTIVELY, FOR STAINING ONLY THE BASOPHILIC MATERIALS OF THE TISSUE, SAID SOLUTION ALSO CONTAINING A BUFFER SYSTEM TO MAINTAIN THE SAME IN AN ACIDIC STATE AND HAVING AN IONIC CONCENTRATION FAVORABLE TO STAINING THE TISSUE AND MAINTAINING THE SOLUTION IN A STABLE CONDITION, THEN TREATING THE TISSUE WITH A REDUCING AGENT TO DEVELOP THE COLOR OF THE STAIN ON THE TISSUE, AND THEN APPLYING TO SAID TISSUE AN EOSIN SOLUTION TO STAIN THE ACIDOPHILIC MATERIAL OF THE TISSUE, SAID EOSIN SOLUTION CONTAINING A MORDANT IN AMOUNT SUBSTANTIALLY THE CHEMICAL EQUIVALENT OF THE AMOUNT OF EOSIN PRESENT, AND A BUFFER IN AMOUNT TO IMPART TO SAID EOSIN SOLUTION A PH OF ABOUT 6 AND HAVING AN IONIC CONCENTRATION FAVORABLE TO STAINING THE TISSUE AND MAINTAINING THE SOLUTION IN A STABLE CONDITION.