GB469132A - Improvements in or relating to the production of cotton-like materials from hemp - Google Patents

Abstract

In a process for obtaining from hemp a product similar to cotton, the hemp is treated with a ferment or diastase at about 45 DEG C., then washed, treated at a pressure of 3--5 atmospheres, e.g. in an autoclave with a resin soap or an alkali and a resin adapted to form a soap, again washed, if desired neutralized, and then bleached, dried and mechanically defibrated. Hemp staples are initially disintegrated by a hatching or steeping treatment and are then treated for 20--24 hours at 45 DEG C. in a tank containing water and a suitable ferment. After washing several times with water, the fibrous mass is treated with an aqueous alkali, e.g. caustic soda (2,5 DEG B<\>ae.) to which is added \ba1/2\be--1 kilo of resin /100 kilos of hemp. This treatment is conducted at 150--155 DEG C. and about 5 atmospheres for not less than 5 hours. Excess caustic soda is employed so that it may be continuously circulated. The resin soaps formed dissolve the gums and resins constituting the cortical tissue of the plants. The mass is washed three times with clear warm water, neutralized with sulphuric acid, again washed and bleached with an oxidizing bath, e.g. a chlorine solution for at least 4 hours. Treatment may be by immersion or the solution may be circulated. Washings with warm water, with dilute sulphuric acid and again with water follow. The mass is then dried, and treated in usual manner to defiltrate it. The product may be spun and the waste used as absorbent cotton.