PERMITTED COAL-TAR FOOD DYES 9 
TABLE 6.—Specifications for tartrazine 
- SSS SO 2 ne Se © an 
seni 4 mieten 
: tolerance Minimum ethod o 
Component (ratio to pure; tolerance analysis 
coal-tar dye) 
Per cent Per cent ‘ Page 
OD PTE ee 6 oe eS eS ee ee ea eee Oa eee iW eae | eo Be Ses 1 
Insoluble matter: 
eappnenes amen, fOr Sot ee Et PL 8 Oe 2 eh asl healt Aa ty: 
©) CETTE ES ee oe ee ee ne Oe ee ane De Veta ex? 15. 
0 a: Tn Gna ae ed aa a a ee a eee Oy > = tps = 15, 16 
| LITE DEL ELn eae Be as Oss 5 SPE SS a See Se ee eee CUT a et Evie re: eee. 17. 
(0 7 LS) 2 ES see ag eee ee eee eee eee ee ee ibe aa 18. 
Sodium in color_____ en A er oe, ee eee Theoretical. |______-_ zeeticd bei $2 
1 0CF IGS Ge 2 re ee oe eee esliitcol pees eens 19. 
OTE pi. -b eee eee Ota eH. Pease ee FS! 19. 
| DED) iiwic ts. Spgs ee ees eee ae eee eee GE genie (Eee ee key 19. 
UTE Le ae eee. ae ee eee egy 19. 
ee eke Be ee ee See ee ree Se era ee eee oe 19. 
LLP ES JR A a ee eee Se eee JOOOTE: [2 ee = 21, 22, 23: 
Ether extractives: 
LED Tiles. 2S as eee Oe Se ee Boe ee Cf). 4) Bes ste se as ow Zay 
EE SEE ee ee ee oe ee Cle Rea hs en os 23. 
2. hese ec atl SE ee eee aes Gye Se eee ts 24. 
“LD SLi fo be ee ee eee eee See ae = ee a2 Ev eet te See cee 24. 
07 DS ET a eee ee ee ‘Pheoretical, —2.2--5 2.2 24. 
OD Rvp ep lle be eo eae Gee See ee ees ie ed eee eee 71.9 | 25. 
SY Tt ae ee ee eee ee Sees © 82.0 | 26. 
Lower sulphonated subsidiary dyes_.-_--------------------- | S10 Sa eee eee 28. 
1 Although no limit is here defined, a statement of the percentage found by analysis must be incorporated 
in the foundation and supplemental affidavits (70). 
YELLOW AB 
Yellow A B (C,,H,:N;), an oil-soluble monazo dye, is made by 
coupling diazotized aniline with 6-naphthylamine (8, 19, 20, 21, 38). 
Both the unchanged portions of the intermediates and the decompo- 
sition products of the diazotized aniline must be removed completely 
from the dye by means of appropriate recrystallizations. 
Yellow A B, an orange powder, crystallizes from alcohol in orange~ 
red plates, melting at 104° C. It is insoluble in water, but dissolves 
in alcohol. The resulting orange-yellow solution is reddened by the 
addition of hydrochloric acid, but is not altered by the addition of 
sodium hydroxide. With concentrated sulphuric acid the dye forms 
a bluish-violet solution, which turns red and produces an orange 
precipitate on dilution with water. It is soluble in carbon tetra- 
chloride and also in vegetable oils. 
TAPLE 7.—Specifications for yellow A B 
Maximum | 
Component tolerance | Minimum| Method of 
(ratio to pure| tolerance analysis 
coal-tar dye) | 
‘ Per cent Se Page 
ATU? 22 Tis 5 Se pa ee eee eee ae le) af ee aS rs SUE 14. 
7 CULE PRE OU ee Bia a a ee ee 5 Tage) (ate ne ae ge 18 
0 LL SS eee ee eee ee Woup. j2as- 2-2: 19 
7: EN Tie. Sr Uses s 9 ee a eal Eee Cee Sa NG 1: 6s Sa eee 22, 23 
0 Sel SEs Te ee Se ee eee: 2) yak Peete de See 26 
Seeaiber insoluble im carbon tetrachloride__-_-.-.---..._-_.--]° °.. Jie. |_-u-u_=.2__- 27 
Water extractives: 
VL Tle. vse se a ee Sa ed BF re eee Ee tp ees See oe 27 
- Lbis-p. 2s tes ee Oe a ee a ee ee i aifgeiad Weer Pia eo | 27 
8 ERE ESET aT ee ee 2 sees Wee ee ROU ee 299 | 28 
_ | Although no limit is here defined, a statement of the percentage found by analysis must be incorporated 
mo eae and supplemental affidavits (70). 
orrected. 
aei2G°— 26} 2 
