Document aB7vVLd0yjBkR5MDjb424y05X

E. I. DU PONT DE NEMOURS & COMPANY PIGMENTS DEPARTMENT 256 VANDERPOOL STREET NEWARK, NEW JERSEY Copy No. / NEWARK PLANT PIGMENT COLOR RESEARCH REPORT Progress Report Stable Strong Benzidine Yellow, S-lf-61 Period Covered: January 1944 FILE: DATE: 221*4 11-29-45 NJSflOB Serial Ho. KH-45-85 Copy Ho. / Copy tot #1 - Humerical Pile 2 - Research Office 3 - library Pile Vff 4 ~ #10 Building 65 - ImpeBrial Chem ical Indusn tries, Ltd* 7- tt 8-0, a, Dawson, Hewark ftu. (d i B -vr* HEWARK PLAST PIGSfflIT COLOR RESEARCH REPORT Progress Report Titles Stahl Strong Benzidine fellow, lt-1961 Period Covered: January 1944 SUBMITTED Bf: APPROVED B5T: V. Chalupskl UC4dUy?/y<' V. Chalupskl DATE SUBMITTED: 11-20-45 %r*. 2 7, /fV^ ' DATE ISSUED: 11-29-45 DUP050150758 2- iaggoiocTioa A Benzidine Yellow of improved strength sad good stability was developed in the laboratory by the use of addition of hydrous tl2 to the toner* Alth further laboratory work on this product was required, a semi-works trial of the formula was made, this was unsuccessful, and the -1941 process as such, was dropped; howeveri the same principle has since been introduced in the XT-553-0 process* A single semi-works batch, 40 lbs., was made on the laboratory 1073-20 process, coded -1961. This involved an orthodox coupling of 3,3,-dichlorbens5idie hydrochloride tetroazotdzed and coupled with aceto-acet-anlllde* The coupled yellow.is heat developed after the addition of tltanyl sulfate solution, which is then neutralized with sodium hydroxide and the slurry quenched. The finished pigment con tains about 78$ of organic toner end 22$ of hydrous TiOg* The role of the hydrous TiQg to prevent loss of strength during storage of the dry pigment, a common phenomenon exhibited by ordinary Benzidine Yellows, The semi-works batch compared with the. laboratory standard was light in asston and quite weak in tint, being only about equal to the weak standard YT-4.59-.jD, See DSK-45-27. DUP050150759