Document 5kNj4Yd40V57maxLJDamJGzpR

E. I. DU PONT DE NEMOURS & COMPANY KREBS PIGMENTS DEPARTMENT 256 VANDERPOOL STREET NEWARK. NEW JERSEY Serial No. KN-?-2 Copy No. Numerical File Period Covered: NEWARK PLANT PIGMENT COLOR RESEARCH REPORT Final Report LEMON YELLOW - Y-524-D DEVELOPMENT OF "B" PROCESS SEPTEMBER 1947 - FEBRUARY 1950 FILE: 211.1 DATE: 2/20/50 MJ279 Serial No. KN-50-2 Copy No* l Copy to* 1 - Numerical File 2 - Research Office (211.1) 3 - Library File (211.1) 4 - V. Chalupskl - Plant Files 5 - D. B. Killian, Newark o - R. R* Deaslow, w 7 - Extra NEWARK PLANT PIGMENT COLOR RESEARCH REPORT Final Report TITLE* LEMON YELLOW - Y-524-D DEVELOPMENT OF "B* PROCESS. PERIOD COVERED* Sept* 1947 - Feb* 1950. CHARGE* 11-3 12-3 DATE SUBMITTED* 2/10/50 DATE ISSUED* 2/20/50 DUP050068049 mim This report represents a summary of the work carried out Intermittently during the period September 1947 to February 1950 on the development and standardization of the high strength lemon yellow, Y-524-D. The early work <1940-1941) is covered in KN-41-28. A plant formula was prepared recently and much of the following material has been taken from the standard formula notes* Additional information will be found in the laboratory notebooks and MD8HW records <see references below)* mm.. There appears to be nothing patentable in either this new process or the product. SUMMARY8 In connection with a Sales Service problem, a brief laboratory study was carried out some years ago (circa. 1940) aimed at developing a yellow similar to Calco'a lemon Yellow 40-2540 for use in the prepa ration of greens* This resulted in a formula, K-1164, which was taken to the semi-works for further study* A number of batches were made embodying several variations and one (lot 4166) was set up as a standard (SD-48105)* The semi-works process was coded as K-1274 (AY-524-0). As the result of a decision by the customer (Adelphi Paint) to use Chrpsme Green rather than yellow/blue and because of the pressure of more urgent items, work on this problem was discontinued early in 1941* The 40-2540 yellow has continued to enjoy wide use (largely in ink) and in 1947 a decision was reached to set up a counter-offering by standardizing Y-524-0 in the plant* The specific objective was to submit an offering to Xntag (Lodi). Eleven batches were made (Oct* Dec* 1947) with only fair success and the best mix which could be made (lot 84577) was rejected by Sales on the grounds of redness of tint* The problem was given active attention In the laboratory and semi-works during the Spring of 1948 and a plant batch (57451) was made in May* This was a "flop" possibly because of an error in the PbO/HAe analysis* After further laboratory and Semi-works study, another plant batch (62O67) was made in November* It was satisfactory on control but the finished product showed bad darkening as a varnish drier rubout was allowed to dry* This poor "stability* was shown to be due chiefly, if not entirely, to moisture in the pigment. Redrying in the plant (lot 89043) was unsuccessful; however, a barrel redried in the semi-works (lot 89296) was fairly satisfactory and while inferior to the old semiworks standard or semi-works production was accepted by Intag and has been used recently as a temporary standard* Six additional 5-mole plant batches were made in the latter part of 1949 under close super vision by the Chemical Division: no unusual difficulties were encountered* They were checks to lot 62067 (89296) and showed fairly good reproducibility. The formula used is the basis for the present MB* process. .1 DUP050068050 - 2- General Y-524-D is a "lemon* yellow greener in masstone and reflected under tone than Y-318 (554)-D but redder than Y-202-D. For its masstone, it is relatively green In tint and strong* Like other typical lemon yellows the masstone is dark (small particle else?} and a tendency is observed in some samples for the masstone to become even darker as the exhibit ages* Its light stability is poor* the chief use of the pigment is in printing ink, although, as mentioned above, it has been given considera tion as a shading yellow for paint. The proposed standard, now being evaluated by Sales Service, is lot 506 and is made up as follows. (Reference1 letter Denslow Spengeman, 1/17/50)* Y-524-P, HS-494 (part of 72088) 200 lbs. y-524-D, US-495 (part of 72071) 200 " Y-493-D, 13490 (SSS) r... g_ (see note) (Hotel The Y-493-D was added to more closely approach the temporary standard, lot 89296). Y-524-D is similar to Calco`s 40-2540 and our Y-599-0. Readings (Tarnish Drier rubouts) of lot 506 made in the Sales Service Laboratory are presented below. Masstone(wet) * (dry) Undertone Strength (4) Tint Y-524-D, lot 506 vs Y^524rP..,..D=ig.3L95 40-??40 --------m----------- --------- (2)---------------------- w------- C-51400 green, vs dull dark, dull O.K. 105 vs.rad it. ,lnt* 3.It.,3.red O.K. O.K. vvs green vvs green wa/va green s.dark vs dk, vs grn. O.K. O.K. 98 102 vs grn.,vs int. vvs red (!) Original semi-works standard. See KH-41-28. (2) Temporary standard for intag. (3) Proposed standard. (4) The strength differences shown in the last three columns are of questionable significance. Like Y-202-D and Y-599-D, Y-524-D uses basic lead acetate liquor as a raw material. The choice is based on economic considerations; litharge can be used and possibly lead nitrate, but indications have been that either of these would give a higher ingredient cost. DUP050068051 3 As Indicated above, difficulties were encountered In initial attempts to operate the "A" formula (Ref* Ktf-41-28) on a plant scale and it was impossible to match,the semi-works standard satisfactorily* This was due to a number of causes some of which are discussed below* The basic trouble, however, was probably the result of too large a batch size together with the high chromate/lead ratio and the very close "acid balance" used to get high tinting strength. Difficulties were also encountered in the laboratory, attributable to the same causes and further complicated by uncertainties in the analytical composition of the lead acetate liquor used in some of the experiments. Semi-works operations were reasonably satisfactory and served as the best means for evaluating the effect of process variables* The pigment is made striking a bichromate/chromate mixture (plus a small amount of sodium purophosphate 3 into basic acetate liquor (TBI) adjusted with acetic acid to a definite acidity. The strike is made under the surface as rapidly as possible (consistent with adequate mixing) precipitating about 89$ of the lead as chromate and pyrophosphate* The exesss lead im precipitated (as lead sulfate) by alum which is followed in turn by additional phrophosphate and soda ash forming, respectively, aluminum phosphate (pyrophosphate?) and "alumina hydrate"* A stoichiometric analysis of the formula la given in Appendix I. The process as finally standardized (Y-524-D(B)) differs from the previous standard ("A") formula, K-1274 set up in 1941 on the basis of semi-works operation in the following respects* 1. The batch size has been cut from 6 to 5 moles* 2* The Chrome/lead ratio has been cut about 3. The quantity of (total) acetic acid has bean increased* 4. Drying conditions have been changed* The comments below are quoted from the standard formula notes on the "B" process* While^the0present formula is apparently more stable than the "A" process, it is sensitive to relatively slight variations in the ratio of ingredients and proper care should be observed in checking weights and using the correct analyses of solutions* Too little acid or absence of a lead excess after striking, for example, may result in a "flop", viz* very red pigment of poor lightfastness which is difficult to consume in other codes* "One of the more likely sources of difficulty is in the PbO/HAc analysis* For this reason, a new analysis is made of the lead liquor after pumping up the first portion to the scale tank* The weight of the second portion of lead and of the supplementary acetic acid is based on the new analysis if it varies appreciably from the original analysis or on an average of the two. Both portions of lead liquor should come from the same make* DUP050068052 4 'The pH of the diluted lead solution (ready to strike) is about 6.8-7*0. It cannot be used as an exact control point since it does not change much with changes in acetic acid* It should serve to detect gross errorsj for example, a pH much above 7*0 would indicate a deficiency in acid which might be serious* "To obtain the proper strike pH it is necessary to have not only the PbO/HAc correct but the chrome/blohrome solution should be adjusted carefully to the designated pH (6*0-6.1). With the N-8/N-10 ratio at 60Q#/5Q#, about 5-10# of W-7 is required. Future experience may make it possible to reach the same endpoint by changing the N-8/H-10 ratio and omitting the H-7* "The green vats (260-261) are used for the strike because of their good agitation and facilities for under-surface addition of the chrome/bichrome. Recent manufacture has been at the 5-mole batch size. It is not known whether a higher concentra tion can be used and any attempt to increase batch size should be made cautiously. "Semi-works experience indicated the desirability of a rapid strike. Scale tank 361 (used for the chrome/bichrome solution) requires about 13 minutes to empty with the valve wide open. During the first 6-7 minutes the pH remains fairly constant at about 7 (it may rise to ca* 7*1) after which it starts to drop and at 9-10 minutes, It drops rapidly torabout 6. During the last few minutes it drops more slowly to a final figure of 5*7-5*9* Experimental (semi-works) batches have been made with as little as 350 lbs* HAc per 1115 lbs. PbO. With this amount of a'.id, the pH dropped to about 6.2 and rose slightly at the end to 6*4. While it gave material of Satisfactory quality, it was probably in the danger zone and with a little less acetic ,acid the lead excess would disappear, the pH would rise to 7 or higher and the batch would flop. The formula directs that a quick test be made for xs lead and if negative an extra (emergency) portion of acetic acid is added. This emergency treatment should help to eliminate "flops" due to some unsuspected error in the PbO/HAc/ CrO* ratio, Until more manufacturing experience has been accumulated it Is recommended that, in addition, a second operator determine the pH of the slurry at the end of the strike and if it is higher than 6.3, add the extra acetic acid even though the lead xs is O.K. A lead excess is, of course, essential* "As in the preparation of other "lemon" yellows, delays in the addition of solutions should be avoided and the batch should be sent to press promptly when finished. The alum, pyrophosphate and soda ash solutions should be prepared and ready before starting the strike and added without delay as indicated in the formula. The making supervisor should check with the press room before striking to make certain that the press is ready to receive the batch* DUP050068053 Only limited information is available on the effect of final pH, If too low (e.g, 5.6), the pigment filters very slowly; if too high (6.5 or higher) there is apparently a tendency towards red ness. As Indicated above, processing of this pigment should he carried through promptly, the press should he set up before starting the batch and pressing started at once. Because of small particle size, pressing is occasionally rather slow with some tendency to "the color is only washed for two hours# However, at the present batch size, this appears fairly effective, "Water soluble salts" in the standard lot were reported as 0.56%. Ohm readings on tha filtrate have not given consistent results. Lot 62067 - 3000 ohms. 70670 - 9000 ohms (4 hrs.) 70695 - Ho reading reported 72034 - 350 ohms 72071 - 400 ohms 72088 - 500 ohms "Complete drying., Under-drled material gives an ink which darkens badly as the exhibit ages. High moisture might also be expected to give abnormal "working properties" in certain vehicles. hours at 170F in the HV dryer is specified. However, the color should be checked before pulling to make certain it is actually dry. She only known effect of over-drying is a slight tendency towards a darker, redder masstone. If difficulties are encountered with a simple "feel" test, consideration should be given to setting up a "Brabender" test. "As in the case of other light yellows, care should be taken to avoid contamination. 'So'difficultias^ave been encountered in part of the process in the course of the development work, "She remarks (above) on drying should be borne In mind and care should be observed that lump color is not damp. Attempts to re-dry pulverized color have not been satisfactory, "Care should be observed to avoid contamination." MFEHEHCESt Additional information can be found in Notebooks 1053, 1281-X and 1305 and in the OSH records. The semi-works studies leading to the "A" formula are reported in KH-41-28* DUP050068054 mwma 6 She "strike acidity" and "precipitant balance" of ingredients reacting with the lead are tabulated below* the assumed chemical composition (qualitative and quantitative) obtained from one mole of FbQ is also shown, (fief, 1305-42). 1sight ingredient Strike lead Holes Product kar.,.mqls..,TO.,. 223 PbO (1 mole) 76 _ Total HAc............. 1*265 120 Bichromate (1) 0.805 0.805 0,805 PbCr04 10 Chromate (1) 0.0672 0.0672 " 2,4 Sod. Pyrophosphate 0.0180 0.00902 Pb2P207 32 Alum (100#) 0.144 0.112 PbS04 3 Sod, Pyrophosphate 0.00375 A14(P207)3 ca. 16 Soda Ash 1 Total equivalents/mole PbO 2.070 0.0406 "Hydrate" (2) 1.034 0.890 (in strike) (1) As Na2Cr27* 2H20 (2) Mol, weight 207* i.e. "hydrate" yield assumed to be 1/3 the weight of "as is" (107) alum used. The calculated composition and goal yield from the above are as followst PbCr04 PbS04 Pb2P2o7 A14(P207)3 Hydrate (m.w.207) Pounds/batch 1410 169 26.5 11.8 -J&u1659.3 t&mmb 83.8 calculated 10.1 " 1.6 " 0.6 " 2.5 n (Continued on page 7) DUP050068055 - 7- aaaagfragfr Total forwarded 1659*3. Water soluble salts 9*4 Moisture 13.4 gamut 98,6 0.56 (by analysis) 0,80 Calc. Coal Yield 1682. 99.96 The percent of PbCrO-in the standard mix (lot 506) by chemical analysis is 84,77#, xhls corresponds to an (analytical) goal yield of 1665, This is believed to be more reliable than the calculated figure) the anhydrous goal yield has therefore been set at 1652 pounds. The available figures on actual yields (from the plant records) are as follows} frot 62067 70670 70695 72034 72071 72088 1642 1525 1591 1619 1622 1634 mwmiLU Standard making formula and processing data attached. DUP050068056 VAT 350 1 s.v. 2 MlSC 3 3r r.nnF: ftnAi Y-524-D (B) k # 1665# s iz e: 5 MOL. DIAZO VAT: f'.nilPUNG VAT: STRIKE VAT: 260, 261 STD. Ho u r s ^.9 NON-BLEEDING, APPROVED BY: JB: 2-7-50 HA: 2-7-50 CWO: 2-7-50 Gt: 2-7-^0 JPL: 2-T6-50 NAME: INSTRUCTIONS USE LBS. No t e : Ev e r y a t t e mp t s h o u l d b e ma d e t o w e ig h b o t h l e a d LIQUOR PORTION PROM THE SAME "MAKE". Ba t c h mu s t p r e s s imme d ia t e l y -c h e c k p r e s s r o o m d e f o i E . STRIKING. 1. Ru n in t o -- sc al e t ank M -- 350 T : R " * 7500 i 2. Ta k e s a mp l e a n d d e l iv e r t o l a b o r a t o r y t o r c h e c k a n a l y s is , NCODE 64 262 ACCT. LBS 0 0 3. Ru n 15" (I320G.) w a t e r in t o s t r ik e v a t * 4. Ru n s c a l e t a n k 350 in t o s t r ik e v a t . 5. We ig h a n d h o l d a t s c a l e t a n k 361 p o r s t e p 35 12 6. We ig h a n d h o l d a t s t r ik e v a t f o r s t e p 25 7, We ig h a n d h o l d a t v a t 365 f o r s t e p 20 8. We ig h a n d h o l d a t v a t 362 f o r s t e p 31 15 I5P 80 9. We ig h a n d h o l d a t s t r ik e v a t t o r e me r g e n c y u s e in s t e p 4* _ (15# 10056) i Tfr T797 12 12 15111 150 3 J1F -~8o 30 10. Re c o r d : s t e p 2 a n a l y s is R ~~ _ ,, 1 4 N-64 % N-262 It. Av e r a g e s t e p s 1 a n d 10 a n d u s e t o c a l c u l a t e a mo u n t w eig h ed in s t ep 1 0 12. Ru n in t o s c a l e t a n k 350 a d d it io n a l TOTAL 1115# FOR STEPS II AND 12 MT l ead R l iq u o r t o _...... * * 64 t: 909 262 64 z a /s 262 i- AH' s.v. 5 13. Ru n s c a l e t a n k 350 in t o s t r ik e v a t . l4. Ad j u s t t o t a l a c e t ic a c id t o 380# M 26\,15. Wh e n u s in g v a t s e t a g it a t o r a t 21 R.P.M, 16. Ad j u s t t o 56" (5I04G.) a t 68-72*F. 17. Te s t a n d r e c o r d : p H . n o r ma l 6.8-7.0. m 6 - 18. Ru n 17" (75G.) w a t e r in t o v a t 365. 19. Tu r n o n a g it a t o r a n d s t e a m. 20. Du mp in N-I5 w e ig h e d in s t e p 7. 21. He a t t o 80-120*F. ~ 22. St ir 5 min u t e s o r l o n g e r t o d is s o l v e . ?6 30 * m Dr u m 7 23. Ru n + 30 G. w a t e r in t o d r u m. 24. t u r n o n s t e a m. 25. Du mp in N-479 w e ig h e d in s t e p 6. 26. He a t t o 80*-1I0*F. 27. St ir 5 min u t e s o r l o n g e r t o d is s o l v e . 28. Ho l d a t s t r ik e v a t c h u t e f o r s t e p 47. W~~ 29. 30. Ru n 6" (72G.) w a t e r in t o v a t Tu r n o n a g it a t o r a n d s t e a m* c o n t in u ed o n 362. PAGE 2. DUP050068057 VAT 361 9 s.v. 10 Pa g e : 2 Co d e : Y-524-D(b ) Us : I665# 31. Du mp in N-3 w e ig h e d in s t e p 8. 32. He a t t o 8o -I20*F. 33. St ir 5 min u t e s o r l o n g e r t o d is s o l v e . In s t r u c t io n s USE LBS. NCODE ACCT. LBS. 34. Ru n I*)" (250G.) w a t e r in t o s c a l e t a n k 361. 3*5. Du mp in N-479 w e ig h e d in s t e p 5. 36. St ir 5 min u t e s o r l o n g e r t o d is s o l v e . 37. Ru n in MT 38. Ru n in MT 39. Ad j u s t t o 57"1950G.) a t 68-72`f . ! 40. Te s t a n d r e c o r d : p H . n o r ma l 5.8-6.0. 6.0-6*41. If n e c e s s a r y , a d j u s t t o p H 1 w it h N-7 o r Re c o r d ; p H 4> $6 N-33 8 600 10 50 1. >8. ' ____ 42. St r ik e s c a l e t a n k 361 a t 68-72*F. in t o s t r ik e v a t AT 68-72'F UNOER t h e s u r f a c e , t h r o u g h t h e d is t r ib u t o r IN 12-14 MINUTES. 43. Wa s h in s c a l e t a n k 361 in + 2 min u t e s . 44. Wh il e w a s h w a t e r is r u n n in g i n . t e s t a n d r e c o r o : s p o t PAPER TEST FOR PBXS , MUST BE 3.+T0 +. USE 490 SODIUM SULFIDE SOLUTION. If NEGATIVE DUMP IN N-30 WEIGHED IN STEP 9. 4*5- Imme d ia t e l y a f t e r c o mp l e t in g s t e p 44. r u n v a t 365 in t o STRIKE VAT IN 2 MINUTES. 46. St ir 1 min u t e w h il e w a s h in g in v a t 365. 47* Po u r in d r u m o f N-479 in 1-2 min u t e s . 48. St ir I min u t e w h il e w a s h in g in d r u m. . 49. Ru n in v a t 362. 50. St ir 5 min u t e s . 51. Te s t a n d r e c o r d : p H 52. If n e c e s s a r y , a d j u s t , n o r ma l 5.9-6-3. t o p H 6.1-6.4 w it h N-3 o r N-33. 53. Fl o o d t o 85" (7400G.). Re c o r o : p H 54. Pr e s s a t o n c e w it h o u t a g it a t io n . TIME START ft tt ii TIME FIN tr it it OPTR ti if K13731 DUP050068058