Document z22e5or1v5rXLpw6bQoV4wXn

E. I. DU PONT DE NEMOURS & COMPANY PIGMENTS DEPARTMENT 256 VANDERPOOL STREET NEWARK, NEW JERSEY Copy No. 1 T TT* T A pV C'C'PY /* NEWARK PLA>T PIGMENT COLOR RESEARCH REPORT SICK LIST STUDY OF HT-435-D j Period Covered i May 1$46 - June 1946. '> I c I FILE. DATE. 7/12/46 ' *t NJdflPO N40001 Kh Serial Ho. KM-46-4? Copy No. i Copy to* 1 - Numerical File 2 - Research Office (221*1) 3 - Library File (221.1) 4 - ,flO Building File 5 - #6 . " 6 - Imperial Chemical Industries, Ltd* *J m II It M II 0M It It H II S - W F, Spengeman NEWARK PLANT FIGMENT COLOR RESEARCH REPORT Progress T'ivtul Report Title* SICK LIST STUDY OF RT-435-0 Period Covered* May 1?46 - June 1?46, SUBMITTED BY* M. G Taber APPROVED BY * J* 0. Morrison DATE SUBMITTED* 7/9/46 DATS ISSUED * 7/12/46 * N40001.01 DUP050150457 ~1 ISTROPUOTIOH Recent plant production has been very dull in raassione# Raw material tests made in March indicated the PNA (N~3?) to be satisfactory* A Plant Assistance Work Request ms therefore issued and study was undertaken in the semi-works* A modified laboratory process was tried in the semi-works during the course of the study* SUMMARY AND CONCLUSIONS Six semi-works batches were made, including one made on the laboratory e,nperimental formula 1118-24B# In all oases the excess nitrite in the diazo was either completely destroyed or, as per K-1929, almost completely destroyed* None of the batches was dull versus standard* The experimental formula which uses a carbonate-bicarbonate type coupling showed no advantage over the present plant method* Drying studies, made on the presacaka of several different batches, indicated that over drhing, even at elevated temperatures (as high as 166*F) could not account for the dullness of masstone obtained in plant batches* Plant difficulty apparently comes from insufficient removal of the excess nitrite* Several recently made plant batches were supervised by the development section at this point in their manufacture and good batches of color have resulted# EXPERIMENTAL DETAILS Semi-works variable stud?/ Lot 3746t The first batch made; it followed the plant formula, K-1929, exactly* Lot 875$& Sulfamic acid was used in place of urea and the excess nitrite was completely removed* Use of sulfamic acid cuts down the diazo stirring time 45-60 minutes# Lot 8751* Sulfamic acid again usedj removal of nitrite was complete| also under surface coupling was used in hopes of cutting down the time required for complete couplings however coupling time was not reduced as had been hoped# Lot 87821 Trial of the laboratory formula, 11X8-24A# 1U8-24A tnploys a carbonate - bicarbonate coupling process such that the pH after coupling is above five* (in the K-1929 process it is only 1*0 to 1*5) Sulfamic is used to cc-^plotely remove the nitrite# Lot 3802s Formula that of 8751 Lot 8803s Reverse coupling; formula otherwise was like 8751* DUP050150458 (l) Xffost of Mkiagi Saoj&oa of Soad-workt proas oak* were drisd *M baked 48 bear* at teaperaturoa ranging ftre 180 * 180* with eat noticeable effoot a roestone iatenoity or on tint* (8) Effort of humidity drying 4 of exposure of pulp to olovato* tooporotaraa for an extended parted (4l bear* iNtfif# drying wfe) A ampla Ml a* palp at 180* raa duller tbaa a control aaaple dried rapidly and bafcod at leO* A ample "feanidity dried? V oapoouro orar 309* Ha*0a for 48 boor* at 140*8* was also dollar than the eeatraU Hon* of tho eanple* were a* dull a* way plant batoboo tor* bow and, since l6o8. ia considerably higher tbaa namel (130*8) plaat dullnees could hardly hare been caused oltbor by baking of the dry oolor or by slow drying of tbo press cake* H.B. 1194-35, 38 and 38 HP 1118 848 SW 87*6, 8750, 8751, 8782, 8808, and 8803* Den * 46-14. DUP050150459