Document dabpv8KYJOpLG8vLBzb7LjRp9

E. I. DUPONT DENEMOURS & COMPANY KREBS PIGMENTS DEPARTMENT 256 VANDERPOOL STREET NEWARK, NEW JERSEY Copy No. / ... NEWARK PLANT PIGMENT COLOR RESEARCH REPORT Progress Report * Siefc List Study oi` Blue forser BT-181-D Period Covered: lovember 1943 - October 1944 /C V V -' FILE: DATE: 223,21 10-10-44 . n jeaas (i _______ N37943 Serial So. copy So* 1 Copy to* **#**a*- it ** Rimsrieol PH# * Eeaoateto Offloo m,ai} - Mtewmw KUt tasy*si> - #iO Btltiag File - Imperial Chemical Industries* Ltd*. *" a # - 8 8 V- Sip* JW f* Daley,' Wilmington (ICI Pile)^ 'iJU, JU* -- * " *- SIWAKK PLMT PimmT COLOR REOEARCR REPORT Titles Progross Report \\ Sick List Study of Blue Toner BT-181-D Period Covered* Soveaber 1945 - October 1944. SQUIITTEB Bit APPROVED BX* DATE SUBMITTED* 10-4-44 DATE ISSUED* 10-10-44 1 DUP050149759 -a- immwm* Assistance w as requested by the plant lat la 1943 because of persistent weakness of production* Borne of the weak sub standard which had been made was blended with the strong Sillco% Molybdate feme? -1962, the development of which Is discussed in another report* Several modifications were introduced Into the BT-1S1-D formula in the course of plant production during the first half of 1944* Fairly satisfactory control appears to have been attained* no further study is contemplated because of the proposed revision in the process to permit larger batch sloes* A recommendation by the laboratory to adjust the pH of the Sodium Tungstate Molybdate solution before forming the FhosphoTungstic-lolybdle Acid was first tried in the plant* A Humber of plant batches with satisfactory strength were thus made. After several trials the amount of dye was reduced from 50 to 48 pounds aas la*. These two changes were Incorporated into a new standard formula -2011. Later attempts to duplicate the good results obtained with this formula were unsuccessful! weak material was again produced* Another change in formula was then made, using the dye on an analysed basis instead of *as isR This was possible because of the development of a modified analytical procedure which appears to give fairly reliable results* Using the dye on an analysed basis good results were obtained from tune to October 1944 (first batch of this series Lot 16592) Two other minor changes which contribute to better operation but probably do not affect quality were also used* l) Dilution of Sulfuric Acid to 1*1 makes It possible to add the acid to the PIMA without shutting off steam} 2) the use of Crystalline Sodium Acetate instead of preparing this from Caustic Soda and Acetic td cid was found to be cheaper because of the small amount involved 10 lbs.)* Other variables tried were a 10$ cut In add which appeared to have no effect In this case, and striking at 190 J instead of at boil, which gave Increased strength but poor light fastness* Tields of individual batches varied as much as 15$ higher or \ lower than the goal yield, but the average of 25 consecutive batches was 90 of goal. \ The changes discussed have been incorporated into a new standard formula, -2064* See DBS 44-16 DUP050149760