Separating pure sclerenchyma fibers from douglas fir bark

Claim 1

THE METHOD OF SEPARATING FROM DOUGLAS FIR BARK SCLERENCHYMA FIBERS WHICH ARE SUBSTANTIALLY FREE FROM OTHER CONSTITUENTS OF THE BARK WHICH COMPRISES REDUCING THE BARK TO A MIXTURE OF PARTICLES HAVING MAXIMUM CROSSSECTIONAL DIMENSIONS OF LESS THAN 1/2'''', THE MIXTURE COMPRISING CORK PARTICLES, CLRK-CONTAINING AGGREGATES, PARENCHYMA PARTICLES, AND SCLERENCHYMA FIBERS ENCRUSTED WITH TIGHTLY ADHERENT SHEATHS PROPORTION OF THE CORK PARTICLES REMOVING A SUBSTANTIAL PROPORTION OF THE PARTICLES AND CORK-CONTAINING AGGREGATES FROM THEMIXTURE, MILLING THE RESULTING FIBER-RICH MIXTURE FOR SEPARTING FURTHER THE PARENCHYMA TISSUE AND THE CORK PARTICLES SCREENING THE MILLED PRODUCT FOR SEPARATION OF A CONCENTRATED FIBER FRACTION (RETAINED) FROM FURTHER QUANTITIES OF POWERED PARENCHYMA AND SMALL CORK PARTICLES (PASSED), ABRADING THE CONCENTRATED FIBER FRACTION FOR REMOVING THE PARENCHYMA ENCRUSTATIONS FROM THE FIBERS, ENTRAINIBG THE ABRADED MATERIAL IN A GASEOUS STREAM, AND SELECTIVELY SEPARATING THE SCLERENCHYMA FIBERS THEREFROM, THE MIXTURE CONTAINING THE ORIGINAL BARK COMPONENTS BEING ADJUSTED