maker, however, usually incorporates the rosin by 

 neutralizing the excess of free alkali with the free 

 rosin acids, after saponification of the fats. Rosin 

 soap is also used in many lubricating greases. 



One of the most reasonable applications is to be 

 found in a paper mill itself. All ordinary papers 

 are sized with rosin, added to the beaters in the 

 form of soap solution and finally precipitated by 

 alum. By dissolving the soap precipitates obtained 

 in the process under discussion, and heating with 

 a certain amount of free rosin, it should not be 

 difficult to provide an emulsion of the composition 

 demanded by the paper maker. 



There are possible drawbacks in a scheme of 

 this kind. The presence of oils in size sometimes 

 results in spotting of the finished paper. However, 

 by careful distillation of the crude turpentine during 

 extraction of the wood, it is doubtful if more than 

 a trace of oily matter would find its way into the 

 finished size. The humus carried down by the 

 colloidal sodium resinate detracts somewhat from 

 the white color of the rosin soap and gives a 

 brownish color to the solutions. It is a question 

 whether the small proportion of humus in the 

 original rosin soap would appreciably affect the 

 value of the directly prepared size, except for 

 use on white papers. Humic salts have even been 

 suggested as possible sizing agents in themselves. 

 (E. Rinman, Svensk Keniisk Tidskrift, see J. Soc. 

 Chem. Ind., Feb. 29, 1912, p. 183). At any rate, 

 reprecipitation with caustic soda offers a convenient 

 method of purification. 



e (3) Paper Pulp : In addition to the products ment- 

 tioned above, it has been shown that the normal 

 yield of high-grade pulp can be obtained from re- 

 sinous pine by the methods described. The whole 

 process, in fact, has been designed with this end in 

 view. The two-stage treatment adapts itself to 

 the employment of any of the so-called " alkaline" 

 processes for final production of fibre. It would 

 not be desirable to use " sulphate" liquor for ex- 

 traction of the rosin, but in a sulphate mill, where 

 the two-stage treatment of rich wood was carried 

 on in conjunction with ordinary pulping operations 



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