engineering gf paints and coatings - general...
TRANSCRIPT
EngineeringGFPaintsandCoatingsInstructors:RyanDenny
TableofContents1. Briefhistoryofthepaintsandcoa8ngsindustry2. Composi8onofmodernpaintsandcoa8ngs3. RawMaterials4. Manufacturingprocess5. QualitycontrolandExperimentaltes8ngprocedures6. Applica8ontechniques
2
Introduction1. Tryandimaginesomethingthatdoesnothavea
coa8ngonit2. PerhapstheWorld’ssecondoldestprofession3. Constantlyevolvingwithnosingleinventor
a. Oil-based,solventborne,waterbornetechnologiesb. Advancesinrawmaterialtechnologyc. Greenini8a8ve(ZeroVOC)
3
PaintsandCoatingsTimeline
4
• 30,000yearsagocavedwellersusedcrudepaintstoleaverepresenta8onsoftheirlives• 1,000BCGumArabicfirstusedtodeveloppaintsandvarnishes
• 600BC-400ADVariousciviliza8onsbeginusingoilsasvarnishesandpigmentandbindercombos• 1500sAr8stsbeginaddingdryingoilstohastenevapora8on;linseedoilbecomesthemostcommon
• 1856HenryPerkindiscoversfirstrealsynthe8cdye• 1865D.P.Flinnobtainspatentforthefirstwater-basedpaint
• 1867D.R.Averillpatents"ready-mixed"paints• 1930sAlkydsforhousepaintsandindustrialuse
• Late1930sEpoxiesaredevelopedforindustrialuses• 1940sNewsynthe8cbindersaredeveloped(polyurethanesandacrylics)
• 1970sPowdercoa8ngsaredeveloped• TodayhybridandUVtechnologiesarebeingdeveloped• Currentlyenvironmentalregula8onsarepushingwater-basedlowVOC/zeroVOCpaintsandcoa8ngs
Composition1. Vehicles
a. Solids-Resinb. Vola8les-Solvents
2. Pigmentsa. Color-hidingpigments(TiO2,Carbonblack,Redironoxide)b. Inert-fillerpigments(calciumcarbonate)c. Effectpigments(Metallic)
3. Addi8vesa. Dispersantsb. Driersc. FlowandRheologicalmodifiersd. Substrateweing/surfacetensionmodifiers 5
Composition
0
10
20
30
40
50
MilkPaintComposi8on
ChalkPaintComposi8on
Pigments
Vola8les
ResinSolids
Addi8ves
• Paintismanufacturedandrawmaterialsarepurchasedviaweightforaccuracy.
• Paintisusedandsoldbyvolume6
CompositionalVocabularyWeight/Gallon=weightperunitvolumePigmenttoBinderra3o=pigmentweight/resinsolidsweightPigmentVolumeConcentra3on(PVC)=pigmentvolume/volumesolids(cri8calPVCisapproximately60%)VOC=weightoforganicsolvent/gallon-water
*Notethatwaterdoesnotcountinthecalcula3onofVOC,soagallonof100%organicsolventhasthesameVOCasagallonof50%waterand50%organicsolvent
*Notesomeorganicsolventsareexempt,meaningtheydonotcontributeVOCtothecalcula3on.Henceyoucanhaveapaintorcoa3ngthatsayszeroVOCthats3llhasorganicsolventwithinit 7
Solvents• Alipha8c• Aroma8c• Alcohols• Glycolethers• Ketones• Acetates• Water• Blendsofthesolventsabove
8
Water1. Considereda“universal
solvent”2. Physicalcharacteris8cs
governtheapplica8onofwaterbornecoa8ngs
3. Evapora8onrateistemperatureandhumiditydependent
a. Controls/Effectsthedryrateandopen8meofthecoa8ng
b. Op8mumcondi8onsare70Fand40%humidity
4. Airmovementwillalterdry8me
9
VOC’s1. Organicsolventsareregulatedbyhowmuchozone/smog
forma8ontheycausecomparedtoethaneasastandard2. Exemptsolventsdonotcontributetosmogforma8onorthe
forma8onisconsiderednegligiblea. Acetone,Methylacetate,andT-butylacetatearesomeexempt
solventsb. No8cethatanexemptsolventcans8llbetoxictohumanseven
thoughitisnotregulatedasaVOC
3. Apaintorcoa8ngcanandwillhaveotherorganicsolventswithinthemeventhoughtheyareconsideredzero/lowVOC
10
IndustryStandards&Regulations
VOC:vola8leorganiccompound;limitedtolessthan420g/Lorlowerdependingonloca8onLabeling:certainmaterialsrequirespecificwarningsSafetyDataSheet(SDS):mustmeetOSHAstandard,mayneedANSIcompliance
11
ResinBinders1. Alkyds2. Polyesters3. Acrylics4. Latexes5. Melamine6. Urethanes7. Epoxies8. Hybrids
12
AlkydsAlkydsaremodifiedwithoilandweusethemineachofouroil-basedproductsonthemarket.
OilTypes
Drying Semi-Drying Non-Drying
Linseed Soya Coconut
Tung Safflower Castor
DehydratedCastorOil
TallOilAcids
FishOil
13
Alkyds• Highlyversa8lechemistry• Householdpaint• Industrialapplica8ons
• Dryviaoxida8on• Canbemodifiedwithotherresinsandchemicals• Styrene• Phenolic• BenzoicAcid• VinylToluene• Rosin• Acrylic• Silicone 14
Acrylics• Dryviasolventevapora8on(lacquer)orcrosslinkingmechanism(urethaneormelamine)
• HighestUVresistanceofallorganiccoa8ngs• Contributevaryingdegreeofcoa8nghardnesstothesystem• Canbeblendedwithotherresinsystemstoimpartdifferentproper8es• Polyurethanesincreasechemicalresistancewhenblendedwithacrylics
15
Polyurethanes• AlsoreferredtoasurethanesorPUD’s• Ambientcurecoa8ngs• Impartexcellentchemicalresistanceanddurability• Cancrosslinkwithacatalyst(2Ksystem)forincreasedperformance,butreducingpotlife
• Canbeblendedwithacrylicstogetbothsurfacehardnessandchemicalresistance
16
FilmFormationMinimumFilmFormingTemperature(MFFT)=theminimumtemperatureneededtoformacon8nuousfilm
17
ColorPigments1. TiO2(Titaniumdioxide)istheonlyhidingpigmentthat
scapers/reflectslight2. Allothercoloredpigmentsabsorblightatspecific
wavelengths3. Blackpigmentsabsorballwavelengthsoflight
18
Opacity1. Opacityisdefinedbyhowmuchthepaintabsorbs,reflects
orscaperslighttohidetheunderlyingsubstrate2. Measuredasapercentonaspectrophotometerovera
sealedwhite,sealedblack,andunsealedwhitesurface
19
ExtenderPigments1. Calciumcarbonate/claysactasfillersatalowcosttospace
outTiO2moleculesforimprovedlightrefrac8on2. Talc/Magnesiumsilicateactsasflapeningagents3. Amorphoussilicaactsasahigh-efficiencyflapener4. Crystallinesilicaimprovesadhesion,fills,andflapens5. Fumedsilicaimpartsrheologicalcontrolandflapens
20
Additives1. Dispersants:surfactantsthathelpthesystemacceptdry
pigmentwithinthegrindphase2. Flow&Leveling:surfacemodifierssuchasfluorosurfactants
andsilanesthatimprovethewepabilityoftheproductovertheapplica8onsurface
3. Rheologymodifier:actstothickenthepaintorcoa8ng4. Defoamers/Deaerators:knockdownfoamforma8onduring
themanufacturingandapplica8onprocess5. Slipaids:surfacemodifiersthatalterhowslipperyasurface
feels6. Biocides:killersofbacteria,mildew,andfungusbothincan
andinfilmforincreasedstability 21
ManufacturingProcessGrindPhaseHighspeeddisperseanydrypigmentorflapeningagentintoeitherwaterortheresinsystemwithadispersantmakingsureyouhaveagoodvortexPremixInaseparatevesselmixtogetherwaterandanysolventneededforcoalescenceofthecoa8ngsoyoudonotshocktheresinsystemwhenaddedLet-downReducethespeedofyourdispersionandaddyourpremixandanyslip-aids,rheologicalmodifiers,biocides,andsurfacemodifieraddi8vestoimproveyourcoa8ngsperformance 22
ManufacturingProcessTechnology:HighspeeddispersionusingaCowlesblade• Agoodvortexpullsthecontentsofthevesseltothebladesedge
• Overchargingorundercharginganyonematerialcanresultinapoordispersion
23
PerformanceCharacteristics1. ChemicalResistance2. WaterResistance3. Heat/HumidityResistance4. YellowingResistance/TanninBleedResistance5. Weathering6. Adhesion7. Incanstability
a. OvenStabilityb. Freeze/ThawStability
24
ChemicalResistanceMethod1. Spraybirchpanelswiththreecoatsofproduct(3drymils)2. Dryeachpanelundera120Fheatlampbetweeneachcoat
andallowthepanelstocureforfivedays3. Applythe21differenthouseholdproductstoeachpanel
beingtested4. Placewatchglassesontopofeachchemicalandallowtosit
foronehourbeforescoring5. Scorethecoa8ng’sresistancetoeachchemicalwithascore
from1-5(1-completedegrada8on,5-noeffect)6. Addupthescoresandcomparetheexperimental
compe88veproductstothestandard(105max) 25
HouseholdProducts• Water• Ketchup• Mustard• Coffee• Iodine• HydrogenPeroxide• Windex• 409Cleaner• Ammonia• IPA• SuntanLo8on
• DEET• Ethanol• RedWine• DenaturedAlcohol• Naptha• Bleach(6%)• AmmoniumHydroxide(37%)
• OliveOil• SulfuricAcid(10%)• SulfuricAcid(37%) 26
TestingPanels
OldExterior450Sa3n NewExterior450Sa3n
27
WaterResistance1. Applyagenerousamountof
waterovertheblackpor8onofthechemicalresistancepanel
2. Placealargewatchglassoverthewaterspotandallowtositforonehourbeforescoring
3. Givethespottestascorefrom1-5similarlytothechemicaltes8ng
4. Lookforblushingandpermanentwaterspots
28
YellowingResistance1. Applyeachtopcoatoveralenetachartwithsnowwhite
milkpaint2. Allowthetopcoattodryatambientcondi8ons(70-75F,
40-50%humidity)3. Takeanini8alcolorreadingusingaspectrophotometerto
showthechangeincolora8onfromthepainttothetopcoat4. Heatstresseachlenetachartina125Fovenandtake
addi8onalcolorreadingsevery24hours5. Analyzethedifferencesincolora8onfromboththesnow
whitemilkpaintstandardandtheini8altopcoatreading
29
Adhesion1. Applya1mm.and2mm.crosshatchtothechemical
resistancepanelsauer24hrsofambientcure2. Placecoa8ngindustrystandardtapetothecenterofthe
crosshatch3. Applypressureandremovethetapetoassessany
delamina8onofthecoa8ngfromthewoodsubstrate
5-PerfectScore 1-Completeadhesionloss
30
QualityControl1. Viscosity2. Gloss3. Color4. Opacity
31
Viscosity1. Viscosityisavaryingstateofthicknessorconsistency
rela8vetotemperature2. CommonlymeasuredinmPas,cPs,orKrebunits3. Temperaturemustbecontrolledwhenmeasuringviscosity
(75Fistheindustrystandard)4. Therearemanydifferentwaytomeasureviscosity,butwe
useaFordcup#4forallofourtopcoatsandaBrookfieldandKrebsviscometersforourpaintsandstains
32
Gloss1. Glossismeasuredonanangletothepaintsurface2. Determinestheamountoflightreflectedbythesurfaceand
ismeasuredinglossunitsnotpercent3. Gloss:85+Semi-gloss:50-60Sa8n:25-35Flat:lessthan154. FlatoutFlat:lessthan5
33
Color1. Viewcolorchangesbasedonvisualobserva8onofthein
processproductdrawndownonalenetachartagainstastandard
2. Useaspectrophotometertomeasurethedifferenceincolorfromtheinprocessproducttoastandard
3. Colorvalueslessthanoneareundetectabletothehumaneye
34
ApplicationTechniques• Brush• Roller• AirAtomizedSpray• AirlessSpray• Electrosta8cSpray• CentrifugalAtomiza8on• AirAssistedAirlessSpray• Dip• DirectorReverseRollcoat(coilcoa8ngs)• CurtainCoa8ng• FlowCoa8ng• FluidizedBed(Powder) 35
SubstrateandPreparation• Wood:sandand/orprime• Sheetrock:sandand/orprime• Steel:ironorzincphospha8zing,prime• Aluminum:passivateandseal• Plas8cs:solventselec8on,productscreening,flametreatment• Magnesium:passivateandseal• Galvanizedsteel:problema8cforconsumer,zincphosphate• Glass:acidetchoruseofadhesionpromoters• Commontheme:Prepara3oniskeyforperformance
36
Wood• Tannins(TannicAcid):Solubleinwater;causeofmajoryellowinganddiscolora8onofwater-basedpaintsandcoa8ngs
• MineralStreaks:Concentratedareasoftannin• VeneerGlue:Somegluesaresolubleinwaterandmigratetothesurfacecausingyellowinganddiscolora8on
• Solu3on:GFSTAINBLOCKINGPRIMER• Oilinessofthewood:Bewaryofsubstratedifferences• Off-labeluse:DONOTRECOMMEND,butsomepeoplehavehadsuccess
37
StainBlockingPrimer
38
Thankyou!
39