﻿PHILIPPINE FIBERS. 95 



or coated papers such as are used in the manufacture of heavy bags 

 which are filled but once and where strength is the important charac- 

 teristic desired. 



The bale of waste upon which the above experiments were made is not 

 considered to be as clean and well sorted as it is possible to obtain this 

 material in practice, in fact I am informed that a much better grade is 

 now being collected and baled in considerable quantities in the provinces. 



An average yield of approximately 50 per cent of strong-fibered stock 

 was obtained in the sulphite digestions outlined above, and this is about 

 what may be expected from the best grades of waste it is possible to 

 obtain, if the baled stuff is thoroughly deviled before it is subjected to 

 any kind of chemical treatment. 



General conclusions. — First. It is essential that the material should be 

 clean and as free from foreign matter as mechanical cleaning processes 

 will make it. 



Second. A preliminary steaming of the charge in the boiler before the 

 sulphite liquor is run in is advantageous mainly because it allows the 

 material to be tamped down and covered with a much smaller quantity 

 of liquor. Most of the materials treated are very bukly in the dry state 

 and sufficient liquor to cover is greatly in excess of the amount necessary 

 to do the work. The running in of cold water and allowing it to 

 discharge answers the purpose. 



Third. Because of the finely divided and porous nature of such mater- 

 ials, no gradual rise of temperature up to the maximum to be carried is 

 necessary, as is true in treating dense, wood chips, but the digester may 

 be heated up to full pressure at once, thus saving three to four hours 

 in time. 



Fourth. The stock is more easily washed and its color, as it appears 

 when it is taken direct from the washing engines, is fully as light as the 

 partially bleached lime or soda pulps made from this class of fibers, and 

 this fact should be strongly emphasized not only because of saving in 

 cost and of the time of a bleaching operation, but also because lignified 

 fibers such as hemp, jute, etc., are very susceptible to chlorination during 

 bleaching, and this seriously impairs the strength of the resulting stock. 



I am not aware that sulphite jute or rope stock have ever been made 

 commercially, but I see no reason why such stock would not be superior 

 to that made by the old process, particularly as this class of fibers is 

 invariably used in the manufacture of low-white or coated products, in 

 which strength is the most important consideration. Mills running 

 on jute, rope, straw, etc., will readilv see the advantage of employing a 

 process which cooks and bleaches a fiber in one operation, thus eliminat- 

 ing the losses of fiber and time incident to extra handling and excluding 

 the solvent action on the fiber which alkaline liquors are known to possess, 

 as well as the liability to deterioration in strength caused by poorly 

 conducted bleaching. 



