Types Of Fatliquors

Transcript

Types of Fatliquors Saponicaon Value • • • • • • Saponifcaton value (or (o r "saponifcaton number"/"Koesor number"/"Koesorer er number“ also reerred o as "sap" in shor) represens he number o milligrams o poassium hydroide hydroide re!uired re!uired o saponiy g o a under he conditons specifed# $ is a measure o he average average molecular %eigh (or chain lengh) o all he ay acids presen# &s mos o he mass o a a/ri'eser is in he ay acids i allo%s or comparison o he average ay acid chain lengh# he long chain ay acids ound in as have a lo% saponifcaton value because hey have a relatvely e%er number o carboylic unctonal groups per uni mass o he a as compared o shor chain ay acids# $ more moles o base are re!uired o saponiy * grams o a hen here are more moles o he a and he chain lenghs are relatvely small given he ollo%ing relaton+ *umber o moles , mass o oil/relatve aomic aomic mass Iodine Value • • • • • • he iodine value (or "iodine adsorpton value" or "iodine number" or "iodine inde") in chemisry is he mass o iodine in grams ha is consumed by -- grams o a chemical subsance# $odine numbers are o.en used o deermine he amoun o unsauraton in ay acids# his unsauraton is in he orm o double bonds %hich reac %ih iodine compounds# he higher he iodine number number he more , bonds are presen in he a# $ can be seen se en rom he able ha coconu oil is very sauraed %hich means i is good or ma0ing soap#  1n he oher hand linseed oil is highly unsauraed unsauraed %hich ma0es i a drying oil %ell suied or ma0ing oil pains# Acid Value • • • &cid value (or "neurali2aton "neurali2aton number" or "acid number" num ber" or "acidiy") is he mass o poassium hydroide hydroide (K13) in milligrams ha is re!uired o neurali2e one gram o chemical subsance# he acid number is a measure o he amoun o carboylic carboylic acid groups in a chemical compound such as a ay acid or in a miure o compounds# $n a ypical procedure a 0no%n amoun o sample dissolved in organic organic solven (o.en isopropanol) is opropanol) is traed traed %ih a soluton o poassium hydroide(K13) %ih 0no%n concenraton and %ih phenolphhalein as a color indicaor# Hydroxyl Value • • • •  3ydroyl value is defned as he number o milligrams o poassium hydroide re!uired o neurali2e he acetc acid a0en up on aceylaton o one gram o a chemical subsance ha conains ree hydroyl groups# 3ydroyl value is a measure o he conen o ree hydroyl groups in a chemical subsance subsance usually epressed in unis o he mass o poassium hydroide (K13) in milligrams e!uivalen o he hydroyl conen o one gram o he chemical subsance# he analytcal mehod used o deermine hydroyl value raditonally involves aceylaton o he ree hydroyl groups o he subsance %ih acetc anhydride in pyridine solven# s olven# &.er completon o he reacton %aer is added and he remaining unreaced acetc anhydride is convered o acetc acid and measured by traton %ih poassium hydroide# Objecve of Fatliquorin • • So.ening o preven he fbre srucure restc0ing during drying • So.ening • 4ubricaton • 5educe he ricton be%een he fbres T!e "oncept of Fatliquorin • • • • • • he charge on he leaher (neurali2aton) can a6ec ali!uoring e6ectveness (charge o he leaher and ali!uor should be same or peneraton) 7eneratng po%er depends on emulsion sabiliy 7artcle si2e disributon an emulsion is a variable ha in8uences sabiliy and peneraton Sulonaton (o ma0e partally sulfed oils) impars more sabiliy han sulaton (o ma0e partally sulaed oils) So.ness depends on he rato o emulsifer racton o neural oil ractons So.ening is in8uenced by he viscosiy and ineracial ension o oils #ec!anis$ of Fatliquorin • • • • he neural oils is ranspored ino he pel as an oil'%aer emulsion he emulsiying agen ineracs %ih he leaher reducing or eliminatng is emulsiying po%er he neural oil is deposied over he fbre srucure' he level o hierarchy o srucure depends on he degree o peneraton he %aer is removed by drying allo%ing he neural oil o ollo% over he fbre srucure Factors A%ecn &ubricaon • 9isributon • 9i6usion • p3 • 7artcle si2e • :iscosiy (higher he viscous beer he lubricaton) Factors Factors A%ecn t!e Applicaon Ap plicaon of Fatliquor • 3igh emperaure  – • =echanical &cton  – • 3eatng he ali!uor o he same emperaure emperaure as he %aer allo%s he oil o brea0 up ino small drops due o he decreased viscosiy (practcally ;-<'especially or vegeable anned leahers) >or miing he ali!uor ino %aer mechanical acton mus be maimised because his he %ay he oil is dispersed ino drops (moorised strrer broom handle) ?aer  – >ormaton o %aer in oil emulsion 'arcle Si(e • • • he partcle si2e o he emulsion is deermined by he degree o %hich he oil is convered ino he sulo derivatve he bigger he sulo o neural oil rato he more solubilised he oil becomes and he partcle si2e is reduced =os a li!uor ormulatons conain abou @-A neural oil B@A sulo racton and B@A %aer )i%erence )i%erence bet*een Sulfated Sulfated and Sulted Fatliquors Sulfated Sulted Stability 4ess =ore +eacve =ore 4ess 'enetraon 4ess =ore A,nity =ore 4ess S1B'C S1DB' srengh srengh Sress so.ness hemical so.ness so.ness so.ness Anionic Fatliquors-Sulfated • • • >or sulatng he oil mus be unsauraed %ih a minimum iodine value o Ehe iodine values is defned as he number o grams o iodine absorbed by -- g o oil or a 1ils ha ha have used us ed are casor casor neasoo soya groundnu cod (sperm oil) 'reparaon of Sulfated fatliquors • • • • • • • • onc suluric acid -'B-A added slo%ly o he oil %ih consan strring strring he emperaure o he eohermic reacton mus be conrolled o less han BF (oher%ise he oil can char resuls in dar0ening and he riglyceride oil may be hydrolysed o release he ay acids he release o ay acids leads o he ormaton ormaton o “spueG %hen he long chain carboylic acids migrae rom he inernal srucure o he leaher o he grain surace visible as %hie eHorescence eHorescence &lenatvely &lenatvely miure o suluric and phosphoric acid (-#F+#-)'his process is epensive bu as Irine %ash+ Jcess ree acid is removed by %ashing he partally sulae oil %ih brine %hich also separaed separaed he oil racton rom he a!ueous racton Irine is used o avoid creatng an emulsion %hich %ould happen happ en i only %aer is used &lernatvely sodium sulae ammonium chloride or sulae could be used *eurali2aton+ *eurali2aton+ Iound and ree acids are neuralised %ih al0ali Sulfan +eacons 'roperes of Sulfaon • &nionic charges increases hence greaer aniy or catonic leaher • 4ubricaton decreases due o he lo%er concenraton o neural oil • Jmulsion partcle si2e decreases • Sabiliy o he emulsion o coagulaton by acid or meal sals increases • • • & high sulaton he oil o il unctons more li0e li0e %eLng agen han lubrican hence he leaher becomes more hyrophilic he leaher becomes looser in erms o brea0 possibly due o he damaging e6ec o he sulae sulae species on collagen 3ydrolysing he oil o creae ree ay acids increases hereby creatng he possibiliy o chrome soaps ay acid spue poor %eLng bac0 uneven dyeing and poor fnish adhesion • 4o% level o sulaton+ sulaton+  –  –  – • =edium level o sulaton  –  – • 4o% sabiliy sabiliy o he emulsion o coagulatng by acids or meal sals# ypically used o lubricae he ouer suraces 9rum oiling o vegeable anned leaher =ore sable o coagulaton hereore greaer poental or peneraton Msed or surace neurali2ed chrome leaher 3igh level o sulaton  – Msed or complee neurali2ed chrome leaher or gloving clohing so.ee leahers Sulted Oils • • • he re!uiremen or he oil is unsauraton or sulatng 7reparaton Sulfaton/oidaton  –  – • &ir is blo%n hrough a miure o -- pars o oil (19) and @- pars o sodium bisulfe soluton %ih strring a ;-'F-< &lernatvely hydrogen peroide may be used insead o air Irine %ash+ ?ashing %ih brine remove acess sodium bisulfe  – here is no p3 adNsumen re!uired due o he use o bisulfe raher raher sulur dioide or sulurous acid 'roperes of Sulted Fatliquors • • • *o charring or dar0ening 3igher emulsion sabiliy o acids hard %aer sals meal ions (&l r) due o he presence o sulonae and hydroysulonae groups and he lo% level o ree ay ay acids or soaps he ali!uor may be ormulaed %ih non'ionic deergen o increase emulsion sabiliy o promoe beer peneraton o ma0e he leaher so.er and uller • here is a danger o giving he leaher loose brea0 • So.ness and srengh or all leahers by deep peneraton • ?ools0ins and urs0ins in mineral anning bahs • $n shrun0en grain producton o minimise loss o ensile srengh srengh in he acidic anning bah Soap Fatliquors • • • • • • 5a% oil (neasoo (neasoo oil) is emulsifed %ih so. soap e#g# poassium oleae he emulsions have a large partcle si2e due o heir endency o have lo% sabiliy sabiliy o %aer hardness and acid he ormulaton ypically has p3 F# & p3 less han ; he soap is increasingly convered ino ree ay acid %hich does no ac as an emulsifer and so he emulsion coagulaes he uses o soap ali!uors are limied o he lo% emulsion sabiliy hey have raditonally been used or surace ali!uoring cals0ins or shoe upper and ormaldehyde anned sheeps0ins or gloving leaher "aonic Fatliquors • • • • • • • • • 5a% oil is emulsifed %ih a catonic agen he hydrophilic group is ypically sraigh chain aliphatc  - o F 4o% aniy or catonic charged leahers e#g# chrome anned leaher 3igh aniy or anionic charged leahers e#g# vegeable anned or lubricatng he ouer layers $ncompatble %ih anionic reagens e#g# anionic dyes ali!uors reans 3igh sabiliy o acid bu unsable o al0ali Oood sabiliy o meal 7oor shel lie Jmulsion sabiliy can can be improved by ormulatng %ih non'ionic deergens (e#g# al0yl ehylene oide condensaes) .on-ionic fatliquors • • • hese ali!uors ali!uors are emulsifed %ih compounds made by condensing ehylene ehylene oide in he presence o an aliphatc alcohol n3BnP'(13B3B) 13 he propertes o he emulsiying agen depend on he value o n he aliphatc carbon chain lengh and he value o  he degree o polymeri2aton polymeri2aton o ehylene ehylene oide  hese compounds are no very good emulsiying agens because he hydrophilic end he ehylene oide chain does no have a high aniy or %aer relying on hydrogen bonding via he eher oygens 'roperes • • • • • • • 3igh sabiliy o meal ions sals hard %aer and %ide p3 olerance =iscible %ih catonic and anionic reagens 4ile or no aniy or anionic or catonic charged leahers he non'ionic emulsifer increases he hydrophobiciy o leahers Msed or ali!uoring Qr and &l anned leahers %hich are highly catonic charged &s a crustng ali!uor or suedes splis i#e# merely o preven fbre restc0ing on drying o aid re%eLng =ay be ormulaed %ih anionic or catonic ali!uors o improve sabiliy #ulc!ared Fatliquors • • • hese ali!uors ali!uors are ormulatons ormulatons o non'ionic anionic and catonic ali!uors in %hich he presence o he non'ionic species prevens prevens precipiaton precipiaton o he anionic and catonic species hey are more sable o a %ider p3 range han singly charged ali!uors and hence more sable o variatons in leaher charge he proportons o he constuens can be varied depending on he leaher propertes re!uired re!uired  –  –  – 9eph o peneraton peneraton Surace lubricaton Jase removal rom pase drying plaes A$p!oteric Fatliquors • • • • • • 5a% oil is emulsifed %ih an amphoeric reagen i#e# one conaining boh acidic and basic groups he poin o neuraliy he isoelecric poin depends on he numbers o acidic and basic groups & ypical $J7 or his ype o srucure is p3 @ & p3R@ he emulsifer is negatvely charged & p3@ he emulsifer is positvely charged charged he choice o p3 o he ali!uors ali!uors depends on he charge o he leaher and he re!uiremen o surace reacton or peneraton Solvent Fatliquors • • • hese are ypically  ypically anionic ali!uors conaining conaining a high boiling poin polar peroleum solven %ih minimum 8ash poin ;-< and preerably preerably odorless he uncton o he solven is o replace he %aer %aer as i is removed during drying ?ih lesser aniy or he leaher han he polar riglyceride oils i can spread urher and deeper