Document 25K69pVyrjLgRRa8J9KoQOQ6

\ iCX . " i #148 ErMinaiion of -1hlt> Lead Association, ft study t o # ade of III a# ot uaJ* Mints to ft 'grinding f; vaxiourcfalU pigment norwil-ly w*0** *" 4W;.(4e); ^a.tn. . for *& fimt eoB^arisen, paste Toluffl f 11 per TOltiM-of pigment* pigment t o oil . , . .t- :i*=the platogxtipb tad ellerod to ate for 20 sdmtes. Jk P**j"c*f ^^cfuinrraelspitghmuse'nptroaddudceitdionsh,onfoeldloawepeda*k palalesteiriintyg VtTSJ LeSnS*&Smfeto fv^lu St the nd. The crea under the o^e' ^ifce work don in mixing the past, cad t o .0 deteroin ty number of unit square. '> i!:3.* . ing N12S18 0007-SWP-00000S789 f *B - Confer plcatbgraph Mixed Pastee With Equal Volumes of Oil per Volume f Pigaont g^ent Gallons Gallons Plastogrcph Beading Curve Piement Oil ' at 0 Min. Peek Area S-W Q. F.' Basic Carbonate - 18 dry '100 175 Si' 5 80 ' Dutch Boy ..Butch Basie Carbonate n* Si iso 160 Batch Boy ITS Basic Carbonate Ka SO 90 ' 98 Butch fey 111' .Basic ' Carbonate K: 85 * 1000 585 Sublimed Basie ^hlphate - 9 dry Oslo 412 Leaded Zinc li .c n no 10S 550 275 . 215 127 'Anatase Titanium Dioxide *- 1405 dry 50 Too dry to mix 1000 - Butile Titahius ..Dioxide --.2175, dry 100 . -* 9 b e . 100 - Magnesium Silicate 2b t dry" `ipO ' R 40 125 52 Precipitated basic carbonate nhite lead Batch Boy ill shoos its characteristic poorer mixing properties colored uith the usual types of carbonate. This is. recognised ty tho producer. 'Anatr.se fi02 shoos con siderable resistance to mixing, 'as does rutile. There are. indications, however* that rutile 2175 dry has bettor nixing qualities than anatase 1405 dry. The next step ms to cohere the pigments' on an equal plasticity tests, in preparation for grinding tests. By varying tho mount of oil the plasticity ms adjusted so that in ell eases a reading of ICQ units was obtained oa the plastogrcph after 20 ninutes. Before addition to the plastograph the pignent and oil were nixed together with a spatula, using 0007-SWP-0000067 the minimum amount ef work necessary to obtain a homogeneous paste, These pastes of equal plasticity were passed through the S-roll 8" Kent sill and the plasticity again determined. The production rate was noted, attempting to grind ail pastes to the same fineness. The magnesium sHi- cate was ground as fine as possible, while'still maintaining a reasonable production rate. - As an approach to an estimate of the portion of the hinder coming under the influence of the surface forces of the pigments, oil absorption values were determined using the standard A.S.T.M* method, using the 80/40 blend of raw linseed .and bodied linseed. The gallons of "bound" oil were determined from these oil absorption values.' '"Total" oil is the total amount in the mixture. "Excess" oil is 'the total oil minus bound oil.. An assumption say be made that'the bound oil clings to the pig ment particles and does not contribute to a lowering of- consistency as does the free oil. Qa tide basis the volume of -"free" oil was calculated per volume'of'pigmopb plus boundi oil* Example: - . 128.5 - gallons total oil per 109 gallons pigment 81.9 bound oil " " " " 76.4 . free H " ' ------ s 9.5 gallons free oil per 100 gallons 100.0. 4- 1.8 pigment plus-bound-oil. * See chart on next page. * 0007-SWP-000006791 -5- . M. VAH LOO Cont. Pastes Of Equal Pre-Grind Plasticity m -EisMSL fSi PMsticite Oil Absorption ; Free'Oil >H a - | vp -i -ov-. ' 'i% 1 ! it II ImS f i it ii 1 i II it - B.C.TT.L. 105 4 r' Dutch Boy Dutch B.C.W.L. 100 5 45 5-0/2 128.3 ` 7.2 51.9 76.4 50.5 ,50 4-5/4 158.8 6.9 49.8 89.0 59.4 ' Dutch' Boy STS B.C.f.L. . . SiS' .* :* - '' Dutch`Boy 111 -B.e.W.L. 105 4 . 99.: . -: &bXiB0d B.S.f.. 100 I ,59 4-5/4 127.7 6.6 47.6 80.1 54.5 15 4-5/4 288.8 11.9 78.0 195.8 no.? 57 e-i/4. 177.5 9.8 66.5 m.o 66.6 [ Loaded Zinc Kt ;> haUle TiQa K Magnesias :* Silicate 101 I 'm i 100 ~4 no' ic 79 ' 6-1/2 . 171.8 25 i ` 500.7 20 5-1/2 505.1 10.5 *65.0 106.8. 64.7 50.8 127.1 175.6 76.2 27.0 120.5 184.6 85.5 .45 2 151.2 20.9 65.5 67.7 41.4 0007-SWP-000006792 Cost. Two adzed pignent pastes were prepared to eoqpcre the calculated plasticity ef Mixtures of too or more pigneats with the actual plasticity. 2;/-- tae 11 requirement of the mix ms calculated on the oil required by the 'i-' iadividual'' pigments t produce a 1C wait plasticity nix. "Actual plnsti.t cities mro;< Pound to b@ slightly lower thoa the predicted 100. Paste Content SO gal. 1403 dry so 18 18 dry f!4 88 oil. llosUgi^ Before ! After MmiBS 1511,1m 90 39 Production Rate Gale, Pig./Rr. 0.20 Fineness S -;.`460 lb 412 dry ;r"140 1403. 200 200 20 P '45 Oil 73 55 .87 Pastes with Equal folums f Oil Per Volme of Pienent A further eoqp&risoa was cr.de using equal wolunos of oil per iVoluae of pignoat. The paste was aired on the posy nixer for .20 ninnies, ^.'Measured on the'plastograph, allied, and aeasured again. In eaeh case j-'lOO gallons, of pigpeni trey used with 175 gallons of oil. Three sine ^cxide easples'"-on to be added to this list. ' ' ' -. jit** / _ " . Plasticity Before Milling _ After IIiHt*y 18 dry B.C.tt.L. Batch Boy Batch * ITS " . a h 9 dry B.SJft.L. 412. leaded line 1405 TiO* 2173 TiOs 20 P % Silicate 55 45 55 182 70 72 650 255 52 22 20 22 55 55 25 205 48 52 0007-SWP-000006793 Sharp decreases in plasticity on grinding indicate incomplete vetting in the mixer. Magnesium silicate was thoroughly wetted in the Eixor .since; no change appeared after application of further meehemied eaerggr by grinding, Q.P. White' Lead and Rational* H.T.S. lead axe obviously easy Wetting. Anatase TiOg is difficult to wet, sore so ,than rutile. . Act 450 added to the above pignents and oil was weary effect ive in increasing wetting in the case of the high consistency titanium oad.de pastes^ but. had a negligible aid variable effect vhm . the original paste consistencies'were low. Ibis my Indicate where wetting agents nay be expected to be, effective. ; Work will;continue' on this project end will Include studies of surface areas,--consistencies at complete wetting, eto, to compare the mlxing-cnd 'grinding properties' of -such pignents. It hope to arrive at a measure to predict nixing and grinding properties of multiple pigment eonbinatiotis':including both active and inactive pignents. As a further step in the Lead Industries Association research, blistering tests were run a various.; types of house paints to determine whether lead carbonate content was of .any benefit in regaining adhesion after blistering .had1 occurred aid the blisters eventually had. subsided. A uhiforn white pine .board' In-two sections was -painted with the -selected . paints.as. two coat systems (48 hours between cor.is) os the face and edges with the te.ek unpalnbed and allowed t dry for one week. Hie panel sections were then mounted on the blistering cabinet (uspolntod back down) with the'carnet|h&:..oi 125 F and saturated humidity.- - After- 72 .hours: the'panels were renovgd to permit the blisters which hod .formed to' sub-' side if' toey would. . 'After drying for .one week, the paint films were ' raked severely with a' rough cioel Hade to determine the adhesion. Hie paint system used included:. mistering - Adhesion ^ests lest Ho. (1st coat 1. ( (2nd coat Materials Aoolled L.I.A. House Paint OJ 456 .J Seduction-Used Per Gallon 1 pint'ram linseed oil 1 pint turpentine No reduction Ea Mj Sl.Sg 56.4^ 0007-SWP-00000679 -0- #148 - Coat. k. van l o o Pont. Blistering - Adhesion Tests Cent. Test No. Materials Applied Reduction Used per Gallon F..V.C. (1st coat to (2nd coat SUP 450 Undercoater L.I.A. Sense Paint OJ 456 J No reduction 57.2$ . 56.4$ (1st coat 5. > (2nd coat Lead-in-Oil L.I.A. Bouse Paint OJ 436 J 100# Soft Paste W.L. 4 gal. Replaeeoent Oil 1-5/4 gel. turpentine 1 pint drier - No reduction 29.1$ 56.4$ (1st coat 4. (2nd coat . Ti-Sil Bouse Point OJ 427 J e .v 1 pint ran linseed oil .1 pint turpentine No reduction 25. S$ 28.9$ (let coat 5. { (2nd coat Ti-Sil Bouse Paint OJ 4SS J B 1 pint mu linseed oil 1 pint turpentine No reduction 81.8$ 56.4$ [let coat Lead-in-Oil 6. 109# Soft Paste ILL. 4 gel; Replacement Oil 1-5/4 gel. turpentine 1 pint drier 29,1? find coat ' Lead-in-Oil 109# Soft Paste ILL. SS.^ - 5 gel. Rcplacenent Oil 1 pint drier1 (1st coat Rex 4S6 - STOP 1 pint ran linseed oil 9.7$ 7. ( ' Pune-Resisting Nhito- 1 pint turpentine (2nd coat No reduction 56.?$ (1st coat 8. f du Pont Moisture Res. H.P. OJ 54 J 1 pint turpentine 59.7$ \2nd coat * No reduction 59.7$ Undercoats at 450 sq. ft./gal. Top coats at 550 sq. ft,/gal. 0007-sw p-000006795 9~ Ms YAH LOO ` ...Pont. Goate Blistering - idhstion Tests -_____ Coat,_________ Test No. Permeability - Mg./Hr Based on 24 Hr. Test Blistering 24 Hours SO Hours - Adhesion 72 Hours 1. 1st coat 2nd n 2. let n . 2nd M , 5. let B 2nd ti 4. 1st a 2nd B 5.'1st- B 2nd a 6. 1st a 2nd 8 7. 1st a 2nd a 8. 1st . a 2nd . a. 2.S 2.7 2.S 2.7 2.9 ' 2.7 2.1. 2.5 1.9 2.0 2.9 ' 5.0 2.6 ' . 2.0 2.i; ' 1.9 None B a Very slight ' Bod ms Def. 4 Fair IWLir Trace Definite Fair 4 . definite Definite 4 Bod a aa Poor Fair - None ' Bad None * ;. @ry bed None .. ted ery goal sy poor Hons None Blight esy good ixz&y It will fee noted that tMle the permeabilities of ' the files'' follow the -blistering tendencies to r. degree, ell the permeabilities ere low and in the son which normally Is definitely below the Bcrilicei* permeabilities. However, there is an apparent relation between lead carbonate content and blistering and' adhesion,. except for the du Pont Moisture Resisting Paint, which contains no lead whatsoever. It is pigmented with TiOa, ZZZ-53 aiac oxide axel fork Whiting in the vacuus bodied 0K0 2-1/2 M linseed oil, at r. p.v.c. of 40. It is vary effect ive in resisting blistering, but it mat bo kept in mind that this is still not an acceptable paint froo a brushing standpoint. 0007-SWE-000006796 I -10- K. VAN mo Cent.' nt; Otherwise two coats.of Itad-in-oil or lead-la-oll under the Lead Industries top coat (46$ leaded sine, 14$ TiOg, 0$ basic carbon ate white lead, 20$ magnesium silicate) or 410 Bndercoater (with 47$ bc^ie carbonate) under the Lead Industries Association paint, showed considerable resistance to blistering and retain adhesion.. The leadfree Rex 456 and the Ti-SIl formulas (a carbonate, 17-1/2$ basic sul fate white lead) show low resistance to blistering, and low adhesion at the end of the test./' /Further tests must be node to take, care of certain necessary Isgproyements in technique but even the data collected so far is suffi cient to stimulate some interesting speculation. . #177 - .Pigment Studies . Following a method suggested by the Newark Technical Service, a series of pigments were evaluated as to dispersion properties for the. Lead Industries; Association. - The Hoover Automatic Muller is used to perform measured amounts .of grinding on pigment in oil mixtures. The degree of dispersion accomplished is measured on the Hegman Gauge. The method used is as follows s . Weigh out 5 gms. of white lead carbonate or its approximate volume . equivalent df other pigments. To this add sufficient oil to give a paste consistency similar to that accomplished with S gas. BCU, and 0,55 ec acid refined linseed oil, 15 A.V. Mull this mixture with a 1G0# wei^t interrupting at each 0 revo lutions for a pick-up end mixing of the paste. To make a fineness reading, reduce the above mixture with 1 ee mineral spirits and test in the usual manner on the Begman gauge. Mixture IF*? ee Oil Beemcn Fineness 100 200 500 400 500 In* * Bsz* Bev. Rev. S-W Q.P. Basie Carbonate Siblimed Basic Sulfc.te Dutch Boy Dutch Dutch Bqy HTS Basic Carb. Dutch Boy HI Oslo 412 Leaded Zinc Annies Titanium Dioxide Futile.: Titanium Dioxide. Magnesium' Silicate 5 gms. 5 5 S 5 2.25 1.50 1.50 1.10 0.55 0.65 0.55 0.55 1.00 0.55 1.00 1.00 0.40 4-5/4 6-1/2 6-1/2 4* 5* 6-1/2* 5-1/2 5-1/2 5-5/4 6 4-1/2 5-1/2 6 - tHS- -* -*- ,,** -** 7 (150) (200) 5 (6^172) (7 ) 5-1/4 5-3/4 5-3/4 5-1/2 6 5 5-1/4 5-1/4 /? 0 0 0 7 -SW P-0 0 0 0 0 6 7 9 7 fi77 - Cent,;'. . U. VAH WO. Pont. '' ' Bulk of material totter than this rating. ' .. ' -persistnt large particlesj however, hulk of material is fine. A few remarks ar pertinent a the above. At conceded by the producer national's Precipitated Mbit Lead 111 has a few large particle which ore hard to grind, the remainder being fine particles. Oslo Leaded 2inc reduces to its ultimate fineness; very rapidly, as does:anatase Ti02 Buttle TiOa (21fS dry); is less easy to disperse, 2he regular lead carten- ates; are easy-to disperse.' Magnesium silicate is still 5-1/2 'after 5Q0 revolutions.'; ' #97.-SHP^JL. ; Lead-Zinc Substitutions in SB? Ihe raw material situation is .such that it has become necessary to provide alternate formulas to use mechanical mixtures of lead carbonate and sine oxide to displace the 412 dry eo-fumed leaded sine oxide normally used ,;in SHF - It is pointed out that this substitution will affect dura' .bilifcy-adversely. fhe adverse effect is minimised fey careful selection "of the sine oxide. Ikposure studies at Coffeyvill, Florida end Chicago j ,-" 'jSr'. indicate" the following zinc oxides to be preferred for durability. 20S9 dry 2295 E 21 1707 H Mew ' Jersey Jl-505 Aso 222-55 Aso 222-11 Azo 22Z-S5 Hew Jersey XX-50 Of the. stove grovp, 214S dry - Aso 222-11 gives too high a consistency for practical formulation and 2295 dry - Aso 222-S5 is on the borderline of high consistent after removing all water from the ' formula, ' * * o - * Hew Jersey* 30C-505 and As 222-55 appear the most likoly sub stitution sine oxides. 1707 dry, H-S0 should be used only as a last resort,, since-its durability is .quite inferior to the other alternates given. All of the above substitutions are made in combination with basic carbonate white lead to replace the 412 dry on a chemical equiva lent basis,, '_ !& - 0 0 0 7-SWP-000006798