Effect of S/B-latex on Coated Layer Structure, 1996 International Printing & Graphic Arts Conference Proceedings

Johan Grön and Tom Grankvist

Åbo Akademi University

Jukka Koskelainen

Dow Suomi Oy

Coated layers have been studied to determine the effects of different S/B-latex types on the surface structure. The aim was to study how S/B-latex and CMC in a coating color effect the surface layer structure to achieve a homogenous surface, which will then serve as a base for additional coating or ink layers The study was performed on coated layers consisting of CaCO3 (90 % < 2.0="" µm)="" pigment.="" carboxymethylcellulose="" (cmc)="" and="" three="" different="" s/b-latex="" types.="" the="" type="" (t,)="" and="" addition="" of="" the="" latex="" was="" varied="" the="" coating="" color="" was="" applied="" with="" a="" trailing="" blade="" coater="" at="" a="" machine="" speed="" of="" 200="" m/min="" under="" constant="" drying="" conditions.="" an="" initial="" determination="" of="" physical="" properties="" of="" the="" coated="" layer="" were="" performed="" to="" provide="" a="" base="" for="" discussions="" regarding="" the="" structure="" surface="" structures="" were="" studied="" with="" scanning="" electron="" microscopy.="" to="" achieve="" a="" better="" understanding="" of="" the="" impact="" of="" water="" in="" contact="" with="" the="" coated="" surface,="" remoisturing="" of="" the="" coated="" layers="" were="" performed="" with="" an="" esem="" (environmental="" sem).="" to="" attach="" the="" observations="" made="" with="" the="" sem/esem-techniques="" to="" a="" printing="" situation,="" the="" paper="" samples="" were="" tested="" for="" ink="" piling="" tendency="" in="" a="" prüfbau="" laboratory="" printing="" unit="" it="" was="" seen="" that="" cmc="" was="" necessary="" to="" keep="" the="" latex="" particles="" in="" the="" pigment="" particle="" matrix.="" an="" even="" distribution="" of="" the="" particles="" prior="" to="" the="" immobilization="" point="" is="" then="" suggested="" to="" give="" a="" better="" film="" forming="" in="" the="" pigment="" matrix.="" it="" was="" also="" observed="" the="" latex="" concentration="" in="" a="" coating="" layer="" will="" effect="" its="" wetting="" resistance.="" a="" critical="" latex="" concentration="" was="" observed="" at="" i5="" pph,="" where="" the="" layer="" was="" more="" prone="" to="" roughening="" and="" cracking="" compared="" to="" either="" lower="" or="" higher="" concentrations.="" l="" present="" address:="" valmet="" corporation,="" paper="" finishing="" group,="" rautpohja,="" fin-40101="" jyvaskyla,="">