| 摘要 |
Agave fibres such as sisal or henequen fibres, or Manilla hemp fibres, are refined and their textile properties are improved by treating them at a temperature of at least 60 DEG C. with an alkali-metal hydroxide solution of aluminium and/or zinc oxide or hydroxide containing less than 15 per cent of alkali metal hydroxide calculated as sodium hydroxide. The treatment removes the binding and encrusting substances between the fibres, such as pectins and lignin, and increases the flexibility of the fibres. The fibres may be treated before spinning or after they have been formed into ropes, yarns, fabrics, bags, or sacks. Preferably, the treating solution contains 3-10 per cent of sodium hydroxide and the temperature of treatment is 80-100 DEG C. Temperatures above 100 DEG C. may be used. The time of treatment may be 1-2 hours. The zinc or aluminium compound is preferably of a concentration at least equivalent to 0.5 per cent of zinc oxide or aluminium oxide calculated on the total weight of the solution. Solutions containing 1-3 per cent of zinc oxide and also 2-6 per cent of aluminium oxide may be used. After the treatment with the alkaline solution, the fibres are squeezed and washed, preferably first with water, then with a dilute solution of hydrochloric or acetic acid, and finally with water. The fibres may subsequently be treated with a mineral or other oil, preferably in emulsion form, to improve the flexibility of the fibres. The oil may be spindle, rapeseed, cotton seed, castor or fish oil.ALSO:Yarns, ropes, fabrics, bags, sacks, and other articles made of crude Agave fibres, such as sisal or henequen fibres, or Manilla hemp fibres, are refined and rendered more flexible by treating them at a temperature of at least 60 DEG C. with an alkali-metal hydroxide solution of aluminium and/or zinc oxide or hydroxide containing less than 15 per cent of alkali metal hydroxide calculated as sodium hydroxide. The treatment removes binding and encrusting substances such as pectins and lignin. The solution may contain 3-10 per cent of caustic soda and the temperature of treatment may be 80-100 DEG C. or even above 100 DEG C. The zinc or aluminium compound may be used in a concentration at least equivalent to 0.5 per cent of zinc oxide or aluminium oxide calculated on the total weight of the solution. Solutions containing 1-3 per cent of zinc oxide and also 2-6 per cent of aluminium oxide may be used. After washing the fibrous material, the flexibility may be further improved by applying a mineral or other oil, preferably in emulsion form. The oil may be spindle, rapeseed, cotton seed, castor, or fish oil. |
