β Scribed by Blair, J.
No coin nor oath required. For personal study only.
Synthctic dycstuffs nrc orgaiiic cliciuicnl compounds wliich havc thc property of dycing ccrtaiii fabrics and mntcrinls in spccific slindcs, w i l l n ccrtniii dcgrcc of fastness to various actions, such ns light, ~vnsliing, ctc. Without this propcrty of fnstncss t h y \vould IN? incrcly stnins and not clycstulls. Tlicy arc npplicd to various inntprinls, wool, cotton, silk, Icnthcr, wood, fat, ctc., according to their solubility, inainly in nil aqueous solution, but also in spirit or fat solntiona, or, if insoluble, by briiigiiig tliciu into solutioii by rcduction as with the so-callcd vat colours. Tl~c tcriu " nniliiic dyes " is oftcn iiscd, but ns only a siiinll pcrccntngc of thc organic dyestuffs is madc from aniline, tliis tcrm is not trnly descriptive. Thc dycing propcrty is duc to their p~rticulnr cliciilical constitution : thcy contain so-callrd " cltromopliorc and ~I I X O C ~I ~O I I I C groups." According to the chroinopliorc groups, thcrc arc about 26 clnsscs of dyestuffs. Thc auxochroine groups, ninido, hydrn, osy, sulpho, ci~rbosyl: ctc. nrc corniiioii to n1l dycstulfs. Tor prncticul purposes a i d h n v i q rcgad to tlic manufncturc t h y nlight IIC c l i ~~~i f ~d ~011iblc dyestuffs nut1 iusolubl~! dycstaffs. Tltc first cntcgory wonld contain the most, important cliisscs, likc azo coloiirs, triplicnylmethnnc, ctc., tlic other clnss tlic sulphur, indigo, nnrl nnthraquinonc tlyestuffs.
Dycstufh arc nianufocturcil froiii con1 tar which, hcforc lS5G, wns n wastc Iiy-product of tlic gas works arid wns used iiiniiily ns n pigiiicrit or a fucl. Wlicn coal is distillcd for the mnniifacturc of gas tlic niaiu by-products arc l)cuzcnc, tolueiic, sylc~ics, phcnols, crcsols, naplithalcuc, nud anthraccnc. A tou ot coal givcs approsimntcly 2 gn11ons of bciizcnc, 3 gallons tolucnc, 20 11). nnplith:ilc~~c, nntl about. G Ib. anthraccnc. Thc colour ninnrif:icturor iist's tli~sc products and be purchuscs thciii from thc coal-tar tlistillers, t l i n t is to sny, thc coke-ovcii proprietors nucl thc gns compnnics.
Jhforc lOld c o l o ~~r mnniifacturing \*as the only soiircc. ol outlet for these products, but tho reinnrkable growth of motoring :tiid thc suitability of benzciic as motor fiwl lins rluitc rcvcrscrl conditions, and to-dny thc dyestuff ma~iuf:tcturcr is only IL 5% uscr of bciizciic ;
π SIMILAR VOLUMES
can be used for bonding many varieties of material, such as plastics, metals, glass, ceramics, wood, concrete, etc. The resins before curing are essentially a thermoplastic. After curing, however, they are crosslinked and transformed into a thermosetting material producing many unique properties tha
IN addressing you this evening upon the subject of Dyestuffs, I am not unmindful of the wide extent of the subject and also of the very great amount of information and data, both general and technically special, that has been given to the public from various sources, since August, 1914 . During this