Charles Frederick Cross

“ The course of industrial development in the 19th century has been one of enormous expansion in use and considerable refinement in methods of preparation and manufacture. Efforts to introduce new forms of cellulose have had little result. Rhea or ramie has been a favourite subject of investigation; the industry has been introduced into England, and doubtless its development is only a question of time, as on the continent of Europe the production of rhea yarns is well established, though it is still only a relatively small trade—probably two or three tons a day total production. ”

“ In the processes of refinement preparatory to the spinning (hackling, scutching) and in the spinning process itself, the fibre-bundles are more or less subdivided, and the divisibility of the bundles is an element in the textile value of the raw material. But the value of the material is rather determined by the length of the ultimate fibres (for, although not the spinning unit, the tensile strength of the yarn is ultimately limited by the cohesion of these fibres) , qualified by the important factor of uniformity. ”

“ Cellulose is extremely resistant to the action of dilute alkalis: a 1–2% solution of sodium hydrate having little action at temperatures up to 150° hence the use of caustic soda, soda ash and sodium silicate in bleaching processes, i.e. for the elimination of the non-cellulose components of the raw fibres. Oxidation in acid solutions gives compounds classed as “oxycelluloses,” insoluble in water, but more or less soluble in alkalis; continued oxidation gives formic, acetic and carbonic acids. Oxidation in alkaline solution is more easily controlled and limited ”

“ As already indicated, paper, which is a web composed of units of short dimensions produced by deposition from suspension in water and agglomerated by the interlacing of the component fibres in all planes within the mass, is a species of textile. Further, whereas the silks are mostly worked up in the extreme lengths of the cocoon, there are various systems of spinning silk wastes of variable short lengths, which are similar to those required for spinning the fibres which occur naturally in the shorter lengths. ”

“ In the analysis of fodder plants and other vegetable produce, the residue obtained after successive acid and alkaline hydrolysis is the “crude fibre” of the agricultural chemist, and is generally taken as a measure of the actual cellulose contents of the raw material. We give in tabular form the average percentage of crude fibre in typical food-stuffs and agricultural produce:—
The above figures have a purely empirical value, since they represent a complicated mixture of various residues derived from the celluloses and compound celluloses. ”

“ I. Textile Fibres are mostly products of the organic world, elaborated in their elongated form to subserve protective functions in animal life (as wool and epidermal hairs, &c.) or as structural components of vegetable tissues (flax, hemp and wood cells) . It may be noted that the inorganic world provides an exception to this general statement in the fibrous mineral asbestos (q.v.) , which is spun or twisted into coarse textiles. ”

“ As a development of the paper industry we must mention the manufacture of paper textiles, based upon the production of pulp yarns. Paper pulps are worked into flat strips, which are then rolled into cylindrical form, and by a final twisting process a yarn is produced sufficiently strong to be employed in weaving.
What we may call the special cellulose industries depend upon specific chemical properties of cellulose, partly intrinsic, partly belonging to the derivatives such as the esters. ”

“ Thus the cellulose nitrates are the bases of our modern high explosives, as well as those now used for military purposes. Their use has been steadily developed and perfected since the middle of the 19th century. The industries in celluloid, xylonite, &c., also depend upon the nitric esters of cellulose, and the plastic state which they assume when treated with solvent liquids, such as alcohol, amyl acetate, camphor and other auxiliaries, in which state they can be readily moulded and fashioned at will. ”

“ The animal fibres are relatively few in number but of great industrial importance. They occur as detached units and are of varying dimensions; sheep’s wool having lengths up to 36 in., the fleeces being shorn for textile uses at lengths of 2 to 16 in.; horse hair is used in lengths of 4 to 24 in., whereas the silks may be considered as being produced in continuous length, “reeled silks” having lengths measured in hundreds of yards, but “spun silks” are composed of silk fibres purposely broken up into short lengths. ”

“ A. The fibre is in virtually continuous lengths. The textile yarn is produced by assembling together the unit threads, which are wound together and suitably twisted (silk; artificial silk) .
B. The fibres in the form of units of variable short dimensions are treated by more or less elaborate processes of scutching, hackling, combing, with the aim of producing a mass of free parallelized units of uniform dimensions; these are then laid together and drawn into continuous bands of sliver and roving, which are finally drawn and twisted into yarns. ”

“ The viscose solution of cellulose is also used for a number of industrial effects in connexion with paper-sizing, paper-coating, textile finishes, and the production of book cloth and leather cloth, and, solidified in solid masses, is used in preparing structural solids which can be moulded, turned and fashioned. ”

“ All animal fibres are effectively dissolved by 10% solution of caustic potash or soda. The fabric or material is boiled in this solution for 10 minutes and exhaustively washed. Any residue will be vegetable or cellulose fibre. It must not be forgotten that the chemical properties of the fibre substances are modified more or less by association in combination with colouring matters and mordants. These may, in many cases, be removed by treatments which do not seriously modify the fibre substances. ”

“ A high lustrous finish is produced, giving the goods very much the appearance of silk.
Of special importance are the more recent developments in the production of artificial fibres of all dimensions, by spinning or drawing the solutions of cellulose or derivatives. Three such processes are in course of evolution, (1) The first is based on the nitrates of cellulose which are dissolved in ether-alcohol, and spun through fine glass jets into air or water, the unit threads being afterwards twisted together to constitute the thread used for weaving (process of Chardonnet and Lehner) . ”

“ Other silicates are also transformed by artificial processes into fibrous forms, such as “glass,” which is fused and drawn or spun to a continuous fibre, and various “slags” which, in the fused state, are transformed into “slag wool.” Lastly, we note that a number of metals are drawn down to the finest dimensions, in continuous lengths, and these are woven into cloth or gauze, such metallic cloths finding valuable applications in the arts. Certain metals in the form of fine wire are woven into textile fabrics used as dress materials. ”

“ Cellulose burns with a luminous flame to carbon dioxide and water; dry distillation gives a complicated mixture of gaseous and liquid products and a residue of charcoal or pseudo-carbon. Chromic acid in sulphuric acid solutions effects a complete oxidation, i.e. combustion to water and carbonic acid.
Ligno-celluloses.—These compounds have many of the characteristics of the cellulose esters; they are in effect ethereal compounds of cellulose and the quinonoid lignone complex, and the combination resists hydrolysis by weak alkalis or acids. ”

“ Carludovica palmata (Central America) yields the raw material for Panama hats, the Corypha australis (Australia) yields a similar product. The leaves of the date palm, Phoenix dactylifera, are employed locally in making baskets and mats, and the fibro-vascular bundles are isolated for working up into coarse twine and rope; similarly, the leaves of the Elaeis guineensis, the fruit of which yields the “palm oil” of commerce, yield a fibre which finds employment locally (Africa) for special purposes. ”

“ Decompositions of Ligno-cellulose.—In addition to the specific resolutions above described which depend upon the distinctive chemical characters of the cellulose and lignone respectively, the following may be noted: to simple hydrolytic agents the two groups are equally resistant, therefore by boiling with dilute acids or alkalis the groups are attacked pari passu. Weak oxidants may also be used as bleaching agents to remove coloured by-products without seriously attacking the ligno-cellulose, which is obtained in its bleached form. Nitric acid of all strengths effects complete resolution. ”

“ In the class of “wrappings” and miscellaneous papers a large number of other materials find use, such as various residues of manufacturing and preparing processes, scutching wastes, ends of rovings and yarns, flax, hemp and manila rope waste, adansonia bast, and jute wastes, raw (cuttings) and manufactured (bagging) . ”

“ The monocotyledons yield still more complex fibre aggregates, which are the fibro-vascular bundles of leaves and stems. These complex structures as a class do not yield to the mechanical treatment by which the bast fibres are subdivided, nor is there any true spinning quality such as is conditioned by bringing the ultimate fibres into play under the drawing process, which immediately precedes the twisting into yarn. ”

“ It must also be borne in mind that the indigestible food residues, as finally voided by the animal, have played an important mechanical part as an aid to digestion of those constituents more readily attacked in the digestive tract of animals. ”

“ There are innumerable vegetable fibres, many of which are utilized in the locality or region of their production, but are not available for the highly specialized applications of modern competitive industry to qualify for which a very complex range of requirements has to be met. ”

“ This product, known as artificial silk, prepared by the three competing processes, was in 1908 an established textile with a total production in Europe of about 5000 tons a year, a quantity which bids fair to be very largely increased by the advent of the viscose process, which will effect a very considerable lowering in the cost of production. ”

“ The variability is a serious impediment in the preparation of the material for spinning and this defect, together with low drawing or spinning quality, limits the applications of this fibre to the lower counts or grades of yarn. ”

“ The common characteristics of the various forms of matter comprised in the widely diversified groups of textile fibres are those of the colloids. Colloidal matter is intrinsically devoid of structure, and in the mass may be regarded as homogeneous ”

“ Derivatives of Ligno-cellulose.—By reaction with chlorine jute yields the derivative C19H18Cl4O9, soluble in alcohol, and in acetic acid; this derivative has the reactions of a quinone chloride. By reaction with sodium sulphite it is converted into a hydroquinone sulphonate of deep purple colour. The reaction of the ligno-celluloses (pine wood) with the bisulphites yields the soluble derivatives of the general formula C26H29O9·SO3H (containing two O·CH3 groups) . Jute reacts with nitric acid in presence of sulphuric acid to form nitrates; and with acetic anhydride to form low acetates. ”

“ The cold concentrated acid rapidly dissolves silk as well as the vegetable fibres. The attack on wool is slow, and the epidermal scales of wool make their appearance. The true silks are distinguished from the wild silks by the action of concentrated hydrochloric acid in the cold, which reagent dissolves the former, but has only a slight effect on Tussore silk. After preliminary resolution by these group reagents, the fabric is subjected to microscopical analysis for the final identification of its component fibres (see H. Schlichter, Journal Soc. Chem. Ind., 1890, p. 241) . ”

“ These cellulose pulps are known in commerce as “sulphite pulps” and “soda pulps” respectively. In addition to these raw materials or “half stuffs” the paper-maker employs the rejecta of the vegetable and textile industries, scutching, spinning and cloth wastes of all kinds, which are treated by chemical (boiling) and mechanical means (beating) to separate the ultimate fibres and reduce them to the suitable dimensions (0.5-2.0 mm.) ”

“ Lastly, composition, which determines the degree of resistance to chemical disintegrating influences as well as subsidiary questions of colour and relationship to colouring matters. The quest for new fibres, as well as modified methods of production of those already known, require critical investigation from the point of view of established practice. ”