100 MARINE PRODUCTS OF COMMERCE 



with dilute acids, limewater, salts of calcium, barium, and various other metals. 

 It may be used for the fixing of mordants in fabrics and, to a limited extent, as 

 a mordant. Ammoniated aluminum alginate becomes insoluble after drying and 

 may be used for the preparation of waterproof fabrics. 



In Japan, Great Britain, and Russia alginates are actually used in the manu- 

 facture of fibers for certain textiles. Textile fibers are produced when a sodium 

 alginate solution is extruded into an acid coagulating bath or one containing a 

 metallic salt solution producing an insoluble alginate. Further treatment or wash- 

 ing will give them added strength. 



Alginic acid fibers possess the disadvantage of being soluble in alkaline solu- 

 tions, but this is not true of chromium alginate and beryllium alginate fibers. 

 Fabrics made from the latter are fire-resistant. 



The property of its alkali-solubility finds an application in making certain 

 fabrics in combination with other textiles. If wool and calcium alginate fibers 

 are woven, the alginate can be removed by washing and a gossamer-like woolen 

 fabric will result. These fabrics make lovely evening dresses which are light as 

 the finest cotton fabrics, yet have the warmth of wool. 



Another somewhat similar use is in the manufacture of lace. A pattern of some 

 other fiber is woven into a calcium alginate cloth; when the alginate is washed 

 out, a lacy pattern remains. In making astrakhan a loose weft of wool and a 

 tight weft of alginate are woven on a wool warp, and the alginate washed out. 



Following the same general principles used in making textile fibers various 

 algin and alginate films and coatings have been prepared. They have an ad- 

 vantage over cellophane since they are almost noninflammable. Algin is utilized 

 to some extent for the coating and sizing of paper to resist the penetration of 

 resins and greases. Alginates are also used in a limited way in the manufacture 

 of wall boards. 



The use of alginates for boiler water treatment dates back to Stanford (1884). 

 The virtue of alginates lies in their reaction with calcium in hard water. The 

 precipitated calcium alginate forms globular, flocculent masses which envelop 

 other sediments to yield a soft pasty sludge, most of which can be blown out of 

 the boiler at regular intervals. The alginates also interfere with crystal formation, 

 and thus prevent scale-deposit. 



Other industrial uses of algin and alginates include the following: Mucilage 

 and other adhesives, water emulsion paints, ceramic glazes and bodies, porcelain, 

 welding rods, asphalt emulsions, cleaning compounds, detergents, polishes, can- 

 sealing compounds, latex creamers and thickeners, leather finishes, fire-retarding 

 compositions, wire-drawing lubricants, insecticides and oil well-drilling muds. 



Pharmaceutical Uses. Alginates also find extensive uses in many pharmaceutical 

 preparations, such as emulsions, tablets, ointments, jellies, and dental impression 

 materials. Other products in which they are sometimes used include: toothpaste, 

 deodorants, shaving cream, mouth washes, shampoo, lotions, beauty "milks", and 

 greaseless hair pomade. Milne (1941) especially recommends its use in vanishing 

 creams and hand "jellies". In making a hand jelly he suggests dissolving 1.5 parts 

 of sodium alginate and 49 parts of glycerol in 35 parts of water, and then adding 

 0.2 part of calcium citrate rubbed with 13 parts of water. After some perfume has 

 been added, the mixture is allowed to stand for 2 or 3 days. 



