Process for preserving plant tissues

Claim 1

A PROCESS FOR PRESERVING PLANT TISSUES, COMPRISING, IMMERSING THE TISSUES IN COLOR STABILIZING AND PRESERVING SOLUTION CONTAINING ESSENTIALLY A VOLATILE WATER-DISSOLVING MONOHYDRIC ALCOHOL, THIOUREA, NON-OXIDIZING ACID SELECTED FROM THE GROUP CONSISTING OF BORIC, PHOSPHORIC AND ARSENIC ACIDS, AND HYDROABIETYL ALCOHOL, SAID SOLUTION BEING ADJUSTED WITH A METAL SALT SELECTED FROM THE GROUP CONSISTING OF ALKALI METAL AND ALKALINE EARTH METAL SALTS TO A PH CORRESPONDING SUBSTANTIALLY TO THE PH OF THE LIQUID MEDIUM OF THE TISSUES IN WHICH THE NATURAL COLORING MATTER IS SUSPENDED, REMOVING THE TISSUES FROM THE SOLUTION AND PERMITTING THE VOLATILE CONSTITUENTS RETAINED IN THE TISSUES TO EVAPORATE, WHEREBY THE NATURAL COLORS OF THE TISSUES ARE STABILIZED AND THEIR PHYSICAL SHAPES ARE RETAINED, THEN IMPREGNATING THE TISSUES WITH A SOLUTION OF A HIGH MELTING WAXY CHLORINATED HYDROCARBON DISSOLVED IN A LOW BOILING VOLATILE ORGANIC SOLVENT, PERMITTING THE SOLVENT TO EVAPORATE, AND APPLYING TO THE IMPREGNATED TISSUES A SUBSTANTIALLY TRANSPARENT MOISTURE-RESISTANT RESINOUS COATING.