Document MGxBN4w9OXKgqJkw03nmrMJXx

\ Kan.- Examination-af.tfaite Land ! . ' ' .. ' Is & portion of our cooperative! work with the lead Industries Assecietioa, a stu<tf uas made of the ease f nixing, dispersion, end grinding f; various iMte-pigments normal.'TLy used in house paint, in a f 0$ (S) and 40 (46) (a used JLm the SS1P vehicle}* ' ipcr.i'v-' . for the first cowards a, pastes were prepared with equal leauaea of oil per velum, of pigment* TUm pigment oa added to' the oil . the plastograph .tad eHowed to mix for 20 minutes. The plasticity .curve pus produced shoved a peak plasticity reeding at the time, of ^^0ent,addition, followed by a lowering to a nearly constant ,^TOxue-at the. end. She area under the eur^re should be proportional to ^on fm mixing" the'.paste,' end vams determined by counting the ^muaber of unit squares. . , .\ W; . N12518 0 0 0 7-SWP-00000G789 M, VAN LOO Cont. p&n - Coat,. . . .. - flaatograph Mixed Pastes With Equal Volumes of Oil per Volume of Pigaont f^ent Gallons Gallons' Plastgraph Beading Curve Pigment Oil ; ' at 20 Min., Peek Area S-W Q. P.' fe6ic Carbonate - 18 dry 100 175 Si 5 80 Batch Boy .Dutch Basie Carbonate II * 65 ' iso 160 Batch Boy HIS Basic Carbonate R .. e . 50 90 ' 98 Butch fey 111 ` Basic Carfenate . s: m 85 * 1000 585 Sublimed Basic gulphate - 9 dry Oslo 412 Leaded Zinc fl e .c ' IS no 10S . 550 275 215 127 Anatase Titanium Dioxide --'1405 . dry. 50 n Too dry to mix 1000 Batii Titaisluffi ..Dioxide - .2175, dry 100 . , - R . b e . 100 _ _ Magnesiaa Silicate -2b'Fd*y '. `lOO R 40 125 52 Precipitated basic carbonate chito lead fetch Boy 111 shoos its characteristic poorer mixing properties cocgtared uiih tho usual types of carbonate. This is recognised ty tho producer. 'Anatr.se fi02 shoos con siderable resistance to mixing, 'as does rutile. Ihere are. indications, however, that rutile 2175 dry has bettor nixing qualities than anatase 1405 dry. ' ' " ' ' ' The next step ms to compare the pigments' on an equal plasticity basis, in preparation for grinding tests. By varying tho mount of oil the plasticity ms adjusted so that in all cases a reading of 10D units ms obtained on the plastograph after 20 minutes. Before addition to the plostograph the pigment and oil were nixed together uith o spatula, using 0007-SWP-000006790 / ggfiir-Sea&t . . M. VAN 3L09 Cent. * ". ' . the minimum amount of work necessary to obtain a homogeneous paste, These pastes of equal plasticity were passed through the S-roll 8" Kent rfil 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 tho influence of the surface forces of the pigments, oil absorption values were determined using the standard A.S.T.K. method, using the 80/40 blend of raw linseed .tad Z2-Z3 bodied linseed. The gallons of "bound18 oil were determined from these oil absorption values.' '"'Total" oil la the total amount in the mixture. "Excess" oil is the total oil minus bound oil. An assurption may be made that'the bound oil clings to the pig- sent particles and does not contribute to a lowering of- consistency as does the free oil. Qa this basis the volume of -"fVee" oil was calculated per volume'of-pigment plus bound; oil. ' .' Example ? - . 128.5 - gallons total oil per 109 gallons pigment . 51,9 bound oil " " . . 76.4 . free oil " ' ------ s 9.5 gallons free oil per 100 gallons 100.0. + 1,9 pigment plus-bound-oil. * ' , See chart on next page. 0007-SWP-000006791 rw fc . ' ft. 4 .: i-.'v/ *1 ' S-' J'ff.' , VAH LOO Cont. ''isi--Si;A.T-!Vi*. Fe*t*t of Equal Pre~Griafi Plasticity Hi#V EI^SSL :3?T\ *** t&-. - iri % glastiei^r Oil Absorption ; Free'Oil : K$&-' *-^'D* * rf x I1 j . S3 fP:- <i. ? . 105 Sj l ?' v.' **'* Dutch Boy Batch Wnr- B.C.I.L. - 100 Dutch' Boy HIS'-.' ^(K BeCel.L. . . . IQS W'if ' ;` ' ' - Butch`Boy 111 " . +$?& -- ' 9. ' 3*`4;.-&msod b .s .w .l . 100 40 SO 40 20 23 84&<0*l 412 Leaded Zinc '$&&*' * :'-J^;Bauta8U 110* 101 . '- ' 96 25 57 %0*?*** ** ' 100 '40 _ i^caosiaa f;M--Silie&te no i7 .43 5-1/2 128.5 ` 7.2 51.9 76.4 50.5 .30 4-5/4 138.8 6.9 49.8 89.0 59.4 .39 . 4-8/4 127.7 ' 6.6 47,6 80.1 54.5 .15 4-5/4 68.8 11.9 76.0 195.8 110.7 .57 -6-1/4. 177.5 9.8 66.5 m.o 66.6 ,79 ' 6-1/2 171.8 ,85. .. ' 500.7 .20 5-1/2 505.1 10.5 65.0 106.8 SO.8 127.1 175.8 27.0 120.5 184.6 64.7 76.2 83.5 .45.2 151.2 20.9 63.5 67.7 41.4 0007-SWP-000006792 Two mixed pigment pastes were prepared to eonpare the calculated plasticity of mixtures f two or more pigments with the actual plasticity, a 11 requirement of the mix mas. calculated a the oil required ty -the lndimiduol' pigments t produce a 100 unit plasticity adx. "Actual plasti cities were;< Found to b@ slightly lower than the predicted 100. . Paste Co r tont "* , SO gal. 1403 dry 'so 18 18 dry -\--fi4' w oil. : r-460 lb. 412 dry 7*140 ' 1403. 200' 11 18 200 8 20 F 45 8 Oil Kfig&ste Before 1 After MmiSS Blil 90 39 73 53 Production Bate Gals. Pig/Br. . 0.10 . 0.87 Fineness 'S Pastes with. Equel Volumes.of ' Oil Per Volume of Pigment . - . A further eorqj&rison was ro.de using equal roluaos of oil per ^volume of pignoat. The paste was. nixed on the poay mixer for 20 nisutei, '.'measured on the plastograph, silled, and scasured again. In eaeh case *100 gallons,f pigpent were used with 175 gallons of oil. Three sine oxide, sasples '* to be added to this list. * ' -. ' 'std:. * . .. . Plasticity Before Milling After Ilillinw 1 dry B.C.tf.L. 35 ' 22 Butch Boy Dutch ; * * ITS ' 8 on * 43 35 182 . 20 . - 22 65 ' . 9 dry B.S.iT.L. 70 SS . - 412. Beaded Bine - ' 72 25 1403 Ti02 850 205 . 2173 TiOs ' . 255 48 20 F % Silicate 32 52 0007-SWP-000006793 M. VAN LOO Confer, fi&B - Coat. . ' . ' Sharp decreases in plasticity on grinding indicate incomplete netting in the mixer. Magnesium silicate was thoroughly wetted in the Eixor since - no change appeared after application of further mechanical aergr by.grinding, S-W Q.P. tihite' Lead and national** fi.T.S. lead ere ' obviously easy wettings Anataso Ti03 is difficult to wet* sore so than rutile* . . ' - ' Acto 450 added to the above pignents and oil was very effect- lve in increasing wetting in the ease of the high consistency titanium oxide pastes*,; .but, had a negligible cad variable effect whoa.the original paste consistencies 'were low. This my ..indicate where wetting agents . nay be expected to be..effective* - ; ". ; ; ' ":: . Work will;continue on this project end will incline studies of surface areas*--consistencies at eoqplote wetting* etc.* to compare the cixing-ond grinding properties' of -such pignents. We hope to arrive'at a measure to predict nixing and grinding properties of multiple pigment combinations Including both active and inactive pignents. ' . : As a further step in the Lead Industries Association research* blistering tests were run; on various.; types of house paints to determine whether lead; carbonate content Was of aay benefit in refining adhesion after blistering had' occurred and the blisters eventually had. subsided. A uhifera white `pine; .board' in two sections was -painted with the -selected paints.as. two coat systems (48 hours between coats) os the face and edges with the back unpainted and allowed t dry for one week. .She panel sections were then noun,tod on the blistering; cabinet (unpointed back down) with the caMsefc raa at l5o F and saturated humidity..- After- 72 hours: th panels were removed to permit the blisters which had.formed to sub side if;'thy]tfwiM After drying for .one week* the paint films were ' raked severely with a' rough. steel. Mad to determine the adhesion. . - ' Ihe paint system used included:. lest Ho. . (1st coat 1. f (2nd coat ' Histerinff - Adhesion Jests ' V' Materials Anwlied ' Seduction-Used - Per Gallon L.I.A. House Paint J 4SS .J -B ' 1 pint'raw linseed oil 1 pint turpentine No reduction Pj .v .Cj 51.3$ 36.4$ 0007-SWP-000006794 -0- . 'HAS - (jat. H. VAN LOO - . Goat. .` Blistering - Adhesion Tests . Cent. Test Wo. Materials Applied Induetion Used oer Gallon ` F.V.C. (1st coat SUP 450 Undercoator - ( "' (2nd oat L.I.A. Sense Paint OJ 456 J No reduction B 57.2% ' 56.4% 1st coat Le&d~ln=Oil . I2nd coat '. fist cent 4. C L.I.A. Bouse Paint OJ 456 J' . Ti-Sil Sous Paint OJ 42? J' . (2nd coat 8 100# Soft Paste V.L.. 4 gal. Replaceoent Oil 1-5/4 gel* turpentine 1 pint drier 29.1% No reduction 56.4$ 1 pint ran linseed oil . 25*5% .1 pint turpentine - No reduction 28.9% flat coot 5. ( ; 2nd coat Ti-Sil Bouse Paint OJ 4SS J 1 pint ro? linseed oil 51.8% 1 pint turpentine . No reduction 56.4* ,1st coat Lead-in-Oil 6e 100# Soft Paste W.L. 4 gal; Replaceoent Oil 1-5/4 gal. turpentine 1 pint drier 29.15 2nd coat ' Lecd-in^Oil - Soft Paste f.L. S gal. Rcplacenent Oil 1 pint drier SS.2% '1st coat Rex. 4Si - SHP .'7. ' Pune .Resisting White ,2nd cent . . K . . 1 pint ran linseed oil 50,7$ 1 pint turpentine No reduction 56.^ '1st coat 8. [2nd coat du Pont Moisture Res HePe 0J 54 J w 1 pint turpentine No reduction 59.7% 59.7% Undercoats at 450 sq. ft./gal. Top coats at 550 sq. ft./gol. 0007-sw p-000006795 H. VAN LOO ` -Pont. JX46 - Conte ' ' '. ; Test No. Blistering - Mhssioa Tests Coni. Permeability Mg./Hr Based on 24 Hr. Test Blistering 24 Hours 50 Hours 72 Hours Region 1. 1st coat 2nd n 2. let . 2nd n R, 2.S 2.7 2.S 2.7 Mono B feiy slight ' Bod me Def. 4 Fair Ihir . 5. let R 2nd t! 4. 1st ft 2nd R 5.'1st- S 2nd _R 6. 1st R 2nd 8 7. 1st E 2nd US .8 1st . Si 2nd 2.9 ` 2.7 2.1 . 2.5 1.9 2.0 2.9 ' ' : 5.0 . 2.6 ' . . 2.0 2.i; 1.9 R definite it None Bad Hons Trace Definite Fair + . Definite + Bad Be Poor Fair - None * None fery good Very-bad V.V. bad Very poor Hone Slight Very good It will fee noted that t &11 the permeabilities of 'the files'' fellow He -blistering tendencies to r. degree, dl the permeabilities ere low and in the son which normally is definitely below the Beritieei* permeabilities. However, there is an apparent relation between lead . carbarnt content and blistering and' adhesion, except for the du Pont Moisture Resisting Paint, which contains no lead whatsoever. It is pigmented with Ti02, ZZZ-53 sine oxide and York ISdting in the vacuus bodied 0K0 2-1/2 M linseed oil, at a p.v.c. of 4Q&. It is vary effect ive in resisting blistering, but it must bo kept in mind that this is still not an acceptable paint from a brushing standpoint. . 0007-SWP-000006796 M. VAN LOO Cent,' |l4e ContL . '. . . . . , Otherwise two coats of lead-in-oil or lead-ia-oll unde? the Lead Industries top coat (46$ leaded sine, 14$ TiOg, 20$ basic carbon ate white lead, 20$ magnesium silicate) or 450 ttodercoater (with 47$ basic carbonate) wider the Lead Industries Association paint, showed considerable resistance to blistering and retain adhesion. The lead- free Rex 436 and the Ti-Sil formulas (no 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, core of certain necessary improvements in technique but even the data collected so far is euffi- eient to stimulate some interesting speculation. . #177 - Pigment Studies ' . ' FeUewing 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 Bagmen Gauge. . The method used is as follows: : - . Weigh out 5 pis. of white lead carbonate or its eppreximte volume equivalent of therpigments. To this add sufficient oil to give a paste consistency similar to that accomplished with S gas. ML and 0.55-ce acid refined linseed oil, 13 l.V. Mull this mixture with a 100# weight interrupting at each 50 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 .. Pi. ee Oil Beemaa Fineness . 100 200 509 400 500 In* *- Hew. Rev. lev. S-W Q.P. Basie Carbonate Sublimed Basic Sulfate Dutch Boy Dutch ' Dutch Bqy HTS Basic Carb. Dutch Boy 111 Oslo 412 Leaded Zinc Anr.tas Titanium Dioxide Futile/. Titanium Dioxide Magnesium Silicate 5 gms. 5 S 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 5-1/2 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 5 ( 150 ) (6^172) ((2700j) 5-1/4 5-5/4 5-5/4 5-1/2 6 -5 5-1/4 5-1/4 5-1 wj'f" .-i. f . . . , fi7? j-fiaay- ' -n- . U VAH LOOPont. '' . \ . . " Tif* v, ' &alk of material batter than this rating. ' . ' ?*&. ?J.V perslstnt large partlelesj houever, bulk.of E&toriaX is floe* Vftgv v:- A fe remarks are pertinent a the above. As conceded by the producer fetioml's Precipitated Tihite Lead 111 has e Sm large particles rfiich are hard- to grind, toe remainder being fine particles. Oslo Leaded 21nc reduces to its ultimate fineness; very rapidlyt as ioeranatas T108 Bitile T102 (2175 dry)- is less easy to disperse. The regular lead carbon ates are easy to disperse. Magnesias silicate is Still 5-1/2 after 500 revolutions.'; . ' '- ; - - 5WP 471 / ': . - Lead-2inc Substitutions in SB? ' . The' rav material situation is such that it has become necessary to provide alternate formulas t use mechanical mixtures f lead carbonate sad sine oxide to displace the 412 dry ; eo-furaed leaded sine oxide normally used in SHP. It is pointed out that this substitution ill affect dura bility adversely. She adverse effect is minimised ty careful selection of the .-sine; oxide.-..:..&iepo.sure.studies- at CoffeyviUe, Florida and Chicago indicate' the .following zinc oxides to be preferred for durability. 059 dry ms ao::> im Me ' Jersey JK-SOS Aso 222-55 As 222-11 As 2ZZ--55 ' .' He Jersey XX-50 Of toe. above group, 2145 dry - As 225-11 gives to high'tr consistency for practical formulation and 2295 dry - Aso 222-55 is on toe borderline of high consistency after removing oil pater from the ` formula, ` ` . ' ' '.* '* " He Jersey's'XX-50S cod As 222-55 appear toe most likely sub stitution sine oxides. 1707 dry, 23C-50 should be used only as a last LV resort, since its durability is .quite inferior to. toe other alternates given. All of- toe above substitutions are mod in combination ith basic carbonate shite lead to replace too 412 dry on a chemical equivn- lent basis,. .' '- ' . ' 0007-SWP-000 0 0 6 798