uv vs eb coating

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Ultraviolet light (UV) and electron beam (EB) curable materials are unique solvent-free compositions that cure (harden) in a fraction of a second upon exposure to a UV or EB source. The absence of solvent eliminates the need for large baing ovens used to process conventional solvent-based coatings (paints) and ins. Industry’s interest in UV/EB curable coating technology began in the 1960s. For exa!le" the be#erage industry’s interest in UV/EB curable coatings $as s!ar%ed by the go#ernent’s announced !rogra to begin allocating natural gas. Be#erage co!anies $ere de!endent on natural gas to !rocess con#entional sol#ent&based in%s and coatings used to decorate be#erage cans. 'he coerciali(ation o) UV cura !"#$ %&'E E* *'T"+E, *E+,-  ble in%s in the 190s enabled be#erage co!anies to accoodate a reduced a#ailability o) natural gas $ith a technology that de!ended solely on readily a#ailable electric energy. +s a bonus" co!anies such as -oors )ound that s$itching to UV curable in%s )or etal can decoration substantially reduced energy and o!erational costs. 'hese sa#ings aounted to ore than one illion dollars !er year see re)erence 1 'he use o) UV/EB curable aterials s!read to other !arts o) the !rinting industry" based on the exce!tional !er)orance !ro!erties this technology o))ers as co!ared to con#entional coatings. 'he in&line a!!lication o) UV curable clear coatings in a con#entional )our&color !rinting !rocess eliinates the need )or s!ray !o$der. *!ray !o$der $as ty!ically used to !re#ent the $et in% )ro o))setting $hile the !rinted stoc% is stac%ed $aiting to be )abricated. By re!lacing s!ray !o$der $ith a UV curable coating on the last station o) the !rinting !ress" the coated stoc% can be iediately )abricated as it coes o)) the !ress. 'he use o) UV coatings signi)icantly increases !roducti#ity by eliinating the need to $ait )or the con#entional in% to dry. 2rinters using UV/EB curable in%s )or general !rinting achie#e additional ad#ances i n !roducti#ity and !rocess #ersatility. 3!tical )iber anu)acturers )ound UV curable coatings to be the only coating technology that $ould satis)y the )ast line s!eeds needed to a%e o!tical )ibers a coercial reality. ' oday " o!tical )ibers are being dra$n at s!eeds greater than 4"000 )eet/inute using UV curable coatings. 'he !rinting and o!tical )iber industries are 5ust t$o exa!les illustrating $hy UV/EB curable coatings are chosen o#er other coating technology )or !er)orance ad#antages. +dditional uses o) UV/EB curable coating technology $ill be discussed later in this !a!er. 'oday’s anu)acturing en#ironent" in $hich go#ernent is i!osing strict reductions in eission o) #olatile organic co!ounds V3- and ha(ardous air !ollutants +2" o))ers another strong incenti#e )or industry to s$itch to UV/EB curable coating technology. Bene)its o) Using UV/EB -urable -oatings In addition to the already entioned )ast line s!eed higher !roducti#ity and sol#ent&)ree co!ositions" UV/EB curable coatings o))er any ore i!ortant bene)its. 'hese include 7 ,educed )loor s!ace 8 UV/EB curing eui!ent is uch ore co!act than con#entional drying o#ens" and the sol#ent&)ree co!ositions reuire less storage s!ace than sol#ent&based coatings !ro#iding co!arable dry )il $eight. 7 *uitable )or heat&sensiti#e substrates 8 'he )ast line s!eeds achie#ed $ith UV/EB curable coatings and absence o) theral drying result in a relati#ely cool coating !rocess $hich can be used )or

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Page 1: UV vs EB Coating

8/15/2019 UV vs EB Coating

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Ultraviolet light (UV) and electron beam (EB) curable materials are unique solvent-freecompositions that cure (harden) in a fraction of a second upon exposure to a UV or EBsource. The absence of solvent eliminates the need for large ba ing ovens used to processconventional solvent-based coatings (paints) and in s.

Industry’s interest in UV/EB curable coating technology began in the 1960s. For exa !le" thebe#erage industry’s interest in UV/EB curable coatings $as s!ar%ed by the go#ern ent’s announced!rogra to begin allocating natural gas. Be#erage co !anies $ere de!endent on natural gas to!rocess con#entional sol#ent&based in%s and coatings used to decorate be#erage cans. 'heco erciali(ation o) UV cura

!"#$ %&'E E * *'T"+ E,

*E+,-

ble in%s in the 19 0s enabled be#erage co !anies to acco odate a reduced a#ailability o) natural

gas $ith a technology that de!ended solely on readily a#ailable electric energy. +s a bonus"co !anies such as -oors )ound that s$itching to UV curable in%s )or etal can decorationsubstantially reduced energy and o!erational costs. 'hese sa#ings a ounted to ore than oneillion dollars !er year see re)erence 1

'he use o) UV/EB curable aterials s!read to other !arts o) the !rinting industry" based on theexce!tional !er)or ance !ro!erties this technology o))ers as co !ared to con#entional coatings.'he in&line a!!lication o) UV curable clear coatings in a con#entional )our&color !rinting !rocesseli inates the need )or s!ray !o$der. *!ray !o$der $as ty!ically used to !re#ent the $et in% )roo))setting $hile the !rinted stoc% is stac%ed $aiting to be )abricated. By re!lacing s!ray !o$der $itha UV curable coating on the last station o) the !rinting !ress" the coated stoc% can be i ediately)abricated as it co es o)) the !ress. 'he use o) UV coatings signi)icantly increases !roducti#ity byeli inating the need to $ait )or the con#entional in% to dry. 2rinters using UV/EB curable in%s )orgeneral !rinting achie#e additional ad#ances in !roducti#ity and !rocess #ersatility.

3!tical )iber anu)acturers )ound UV curable coatings to be the only coating technology that $ouldsatis)y the )ast line s!eeds needed to a%e o!tical )ibers a co ercial reality. 'oday" o!tical )ibersare being dra$n at s!eeds greater than 4"000 )eet/ inute using UV curable coatings. 'he !rintingand o!tical )iber industries are 5ust t$o exa !les illustrating $hy UV/EB curable coatings are choseno#er other coating technology )or !er)or ance ad#antages. +dditional uses o) UV/EB curablecoating technology $ill be discussed later in this !a!er.

'oday’s anu)acturing en#iron ent" in $hich go#ern ent is i !osing strict reductions in e ission o) #olatile organic co !ounds V3- and ha(ardous air !ollutants +2 " o))ers another strongincenti#e )or industry to s$itch to UV/EB curable coating technology.

Bene)its o) Using UV/EB -urable -oatings

In addition to the already entioned )ast line s!eed higher !roducti#ity and sol#ent&)reeco !ositions" UV/EB curable coatings o))er any ore i !ortant bene)its. 'hese include7 ,educed )loor s!ace 8 UV/EB curing e ui! ent is uch ore co !act than con#entional dryingo#ens" and the sol#ent&)ree co !ositions re uire less storage s!ace than sol#ent&based coatings!ro#iding co !arable dry )il $eight.7 *uitable )or heat&sensiti#e substrates 8 'he )ast line s!eeds achie#ed $ith UV/EB curable coatingsand absence o) ther al drying result in a relati#ely cool coating !rocess $hich can be used )or

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coating heat sensiti#e substrates" such as !lastic" $ood and !a!er.7 ,educed in&!rocess in#entory 8 + con#entional ther al curing coating anu)acturing !rocess"re uiring inter ediate drying stages" can be con#erted into a single&ste!" in&line !rocess $ith UV/EBcurable coatings.7 :o$er insurance costs and reduced handling ha(ards 8 *ol#entless UV/EB curable coatings arerated as non&)la able li uids. 'his $ill result in reduced insurance costs" less stringent storage

re uire ents and a reduction in handling ha(ards co !ared to )la able sol#ent&based coatings.7 -o !liant technology 8 Federal" state and local go#ern ents recogni(e the any ad#antageso))ered by UV/EB curable coatings in co !lying $ith V3- and +2 restrictions see re)erences ;" <and = . For exa !le" UV curable coatings )or etal can a!!lication has been re!orted by the E2+ tocontain less than 0.01 V3-/gallon o) coating see re)erence 4 . -oors re!orted no signi)icante ission o) o(one or other undesirable e issions )ro a UV can line )or one billion cans !er yearsee re)erence 6 .7 ,educed costs 8 *e#eral studies sho$ a signi)icant reduction in energy costs can be achie#ed bys$itching )ro con#entional ther al curing coatings to UV/EB curable coatings. +dditional studiessho$ that s$itching to UV/EB curable coatings is less ex!ensi#e than con#erting an existing sol#ent&based coating o!eration into a V3- and +2 co !liant o!eration see re)erences and > .7 2ro#en technology 8 UV/EB curable coatings are a !ro#en technology" used $orld$ide" that hasbeen in co ercial use since the 1960s.

'he -he istry o) UV -urable -oatings

?ost co ercially used UV curable coatings are based on acrylate che istry that cures #ia )reeradical !oly eri(ation. 'hese li uid co !ositions ty!ically contain a ixture o) a reacti#e oligo er<0 8 60@ " one or ore reacti#e ono ers ;0 8 =0@ " a UV light&absorbing co !onent < 8 4@ "and one or ore additi#es A1@ . UV/EB curable in%s ay contain u! to ;0@ !ig ent. + high!ig ent content such as used in UV in%s ty!ically re uires u! to 10@ o) !hotoinitiator

3ne o) the any ad#antages o) acrylate&based coatings is the extensi#e nu ber o) oligo erscontaining urethane grou!s that can be !re!ared to eet a $ide range o) cured )il !ro!erties.2olyols used to !re!are urethane acrylates )or UV/EB co !ositions include !olyethers" !olyesters.

!olybutadienes" etc.enerally" a ixture o) ono)unctional one acrylate grou! and !oly)unctional ore than oneacrylate grou! acrylates is used in order to o!ti i(e cured )il !ro!erties and li uid coating cures!eed. ?ono)unctional ono ers tend to reduce #iscosity ore e))ecti#ely than !oly)unctionalacrylates. 'he ono)unctional ono ers also reduce cured )il shrin%age and increase theelasticity o) the cured )il . o$e#er" a high concentration o) ono)unctional ono er se#erelyreduces the coating cure s!eed. ighly )unctionali(ed ono ers increase coating cure s!eed andincrease cured )il resistance to abrasion. o$e#er" these t$o desirable cured )il )eatures areachie#ed at the sacri)ice o) e brittling the cured )il and reducing adhesion to the substrate.3!ti i(ed coating !ro!erties are achie#ed by syste atically balancing the oligo er and ono erconcentrations.

'he UV light absorbing co !onent" called a !hotoinitiator" initiates the !oly eri(ation !rocess u!onex!osing the li uid coating to an intense source o) UV light. 2hotoinitiators ty!ically absorb light int$o $a#elength regions ;60 n and <64 n . 'he absor!tion at the higher energy can be u! tose#eral orders o) agnitude greater than the absor!tion at the lo$er energy longer $a#elength .'he !hotoinitiator deco !oses at a rate signi)icantly )aster than the rate o) !oly eri(ation. It is thisra!id !hotodeco !osition that results in UV curable coating !oly eri(ing instantaneously u!on UVex!osure.

+ #ariety o) !hotoinitiators are a#ailable that di))er in $a#elength absor!tion and echanis )or

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initiating !oly eri(ation. Ca#elengths o) intense absor!tion tend to )a#or coating sur)ace cure $hile$a#elength o) lo$er absor!tion tends to )a#or coating through cure. *o e a!!lications re uire aco bination o) t$o or ore di))erent !hotoinitiators to achie#e o!ti i(ed cured )il !ro!erties andcoating cure s!eed.

+dditi#es are a co on ingredient ty!ically used to o!ti i(e coating !ro!erties" such as li uid

coating shel) li)e" cured )il durability" adhesion to substrate and general cured )il a!!earance.

'he second ost $idely used UV curable co !osition is the cationic&cured coatings. -ationically&cured coatings are based on e!oxy&!olyol co !ounds that !oly eri(e in the !resence o) an acid.'he !hotoinitiator used in cationically&cured co !ositions generates a Bronsted acid u!on ex!osureto UV light. 3ne o) the dra$bac%s in the cationically&cured syste s is the li ited ra$ ateriala#ailable )or use in these )or ulations. + co !arison o) the cationically&cured and )ree radical curedcoating syste s is sho$n in 'able 1.

'he -he istry o) EB -urable -oatings

+crylate and e!oxy&!olyol co !ositions that cure $ith UV light can be cured by ex!osure to high&energy electrons co only re)erred to as EB curing. 'he electrons used in the curing !rocess range)ro >0 to as high as <00 D#. 'he higher the #oltage the dee!er the electrons !enetrate into thecoated substrate. In the case o) acrylates" no !hotoinitiator is re uired )or EB curing. o$e#er"cationically&cured co !ositions re uire a s all a ount o) acid !roducing !hotoinitiator. +co !arison o) UV #ersus EB curing is sho$n in 'able ;. 'able < sho$s UV light sources and 'able =sho$s EB sources.

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UV :ight *ources

EB *ources

-ure ,e uire ents

In general" UV curable coatings re uire a dose or radiant energy density o) bet$een 0.4 to <.0oules/c ; to achie#e )ull cure at reasonable line s!eeds. +dditional cure ay result ine brittle ent and/or discoloration o) the cured )il .

Chen curing $ith EB" it is critical to o!erate at the #oltage that is o!ti u )or the density o) thecoating being cured. 'oo high a #oltage $ill result in ost o) the electrons !assing through thecoating $ithout e))ecting a cure. 'oo lo$ a #oltage $ill result in too )e$ electrons !enetrating the

coating layer. 'he unit o) easure ent used )or dose in EB curing is called a ?egarad ?rad . +ty!ical !o$er rating )or a EB curing unit is 1"000 ?rad eter/ inute. 'his eans the EB unit deli#ers1 ?rad at a line s!eed o) 1"000 eter/ inute. ecreasing the line s!eed by one&hal) doubles thea!!lied dose. + ty!ical dose used )or EB curing is bet$een 0.4 and <.0 ?rads. It is i !ortant to usethe ini u dose re uired to !ro#ide satis)actory )il !ro!erties in EB curing as a higher dose ayresult in substrate degradation.

+s $ith any other coating syste " it is i !ortant to utili(e a test ethod )or deter ining $hen theUV/EB coating is )ully cured. *e#eral techni ues" $hich can be used indi#idually or in co bination"

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are as )ollo$s7 ?easuring a )unctional !ro!erty 8 )or exa !le" )il odulus" )il hardness" )il adhesion and )ilgloss7 Using a che ical ethod 8 )or exa !le" s!ectrosco!ic easure ent o) residual unsaturation"sol#ent extractables"cured )il #olatiles" and cured )il sol#ent sensiti#ity.

+!!lications o) UV/EB -oatings

-oatings )or $ood

UV/EB curable li uid coatings are used )or #arious $ood a!!lications including abrasion resistant)looring" asse ble yoursel) )urniture" sealers and basecoats" !articleboard EB " si ulated$oodgrain trans)er la inates EB " tri oldings" and baseboard. + #acuu a!!lication techni ue isused to a!!ly the UV coatings to tri oldings and baseboard. +d#antages o) UV/EB coatingsinclude )ast line s!eed" excellent stain resistance" and durability.

-oatings )or !lastic

-oatings )or $eb )or !lastic )il s

UV curable coatings are used )or coating #arious !lastic )il s including !olycarbonate" !olyester"and !oly!ro!ylene. 'hese coatings are a!!lied on a $eb line and o))er line s!eed and !er)or ancead#antages o#er con#entional coatings. +!!lications include solar control !lastic )il s" a!!liancetouch !anel )il s and dis!lay )il s. In addition to )ast line s!eed and absence o) sol#ent" thesecoatings o))er desirable cured )il !ro!erties" such as !rint rece!ti#e )il s" #arying cured )iltextures" and excellent resistance to stain and abrasion.

-oatings )or - s and V s

'he ra!id cure s!eed o) UV curable coatings has enabled anu)acturers o) - s and V s toaxi i(e anu)acturing line s!eed G < to = seconds !er unit . '$o di))erent ty!es o) UV aterialsare used in the anu)acture o) - s. First" a UV abrasion resistant clear coat is s!in coated onto theetal re)lecti#e layer. 'he !rotected etalli(ed sur)ace is then screen !rinted $ith a UV curable in%.In the case o) V s" a UV curable adhesi#e is used to bind the !rotecti#e !olycarbonate layer to theetalli(ed !olycarbonate layer. 'he #iscosity o) the - clear coat #aries bet$een 10 to 100 c!s at;4o -" and the #iscosity o) V adhesi#es is less than 1"000 c!s at ;4o -.

Electronics

2rinted circuit boards are !rotected )ro harsh en#iron ental conditions $ith a UV curablecon)or al coating. 3ne o) the challenges in de#elo!ing a UV curable con)or al coating is theirregular sur)ace o) the !rinted circuit board. 'he cre#ices and hidden areas created by the irregular

sur)ace a%e it i !ossible to achie#e co !lete line&o)&sight curing. For ulators ha#e de#elo!edcoatings that undergo !ost curing in areas that ha#e not been directly ex!osed to UV light.

-oatings )or <& substrates

-uring techni ues ha#e been de#elo!ed )or curing UV curable coatings a!!lied to a three&di ensional substrate. 'he coating is a!!lied either by s!ray a!!lication or #acuu de!osition. 'hecoated substrate" sus!ended on a con#eyeri(ed syste " is then rotated in )ront o) a series o) UVla !s !ositioned to ex!ose the entire coated sur)ace to UV light. +!!lications include to!coats )or

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$ooden )urniture and !olycarbonate headla !s. Basecoat s and to!coats are used )or #acuuetali(ed !er)u e lids" auto oti#e headlight re)lectors" !lastic door handles" and !lastic )lo$er!ots.

+nother three&di ensional a!!lication is a base coat sealer used on *?- auto oti#e )enders. 3neo) the a5or ad#antages the UV curable sealer o))ers )or #acuu etali(ed !lastic !arts is!re#ention o) outgasing during the #acuu etali(ation !rocess.

+dhesi#es

UV la inating !ressure sensiti#e and glue a!!lied adhesi#es )or labels include )il to !a!er and )ilto )il . 'he labels are !rinted $ith either a UV or $ater&based )lexo in%" and the UV adhesi#e isa!!lied on the last station. 'his is )ollo$ed by attach ent o) the )il " and the )il la inate isex!osed to UV light )or curing. 'his la ination techni ue has the ad#antage o) being carried out in&line at a lo$er cost than using con#entional adhesi#es. +d#antages o) UV/EB la ination includeachie#ing )ull bond strength i ediately u!on cure" stabili(ing the adhesi#e until cured" andeli inating #iscosity ad5ust ents.

+nother ty!e o) UV curable adhesi#e in co ercial use is the Hasse blyH adhesi#e. 'heseadhesi#es are used in the anu)acture o) cell !hones" edical de#ices such as catheters andsyringes" auto oti#e !arts and o!tical )iber s!lices. 'hese adhesi#es are ty!ically dis!ensed $ith asyringe and cured $ith a Hs!otH curing de#ice in&line. 'he ad#antage in using the UV curableadhesi#e is the ra!id cure that allo$s the !roducts to be co !letely asse bled in&line. + )luorescentdye is co only added to UV curable adhesi#es as an ins!ection aid to insure the adhesi#e )lo$ed!ro!erly in the de#ice.

,elease coatings

Both UV and EB curable release coatings are in co ercial use. :ine s!eeds )or these coatings runabout 1"000 )eet/ inute. 'he UV release coating is based on cationic curing and can be !rocessedin o!en air $hile the acrylate&)ree radical based syste s ust be cured in a nitrogen gasat os!here. ,elease !ro!erties are co !etiti#e $ith non&UV/EB release coatings.

?etal a!!licational#ani(ed steel !i!ing is !rotected $ith a UV curable coating a!!lied in&line as the last ste! in the!i!e anu)acturing !rocess. 'he coating !ro#ides !rotection against $hite rust $hile the !i!e isstored outdoors. 3riginally" the coating $as a!!lied by a s ueegee a!!licator. ?ore recently" a#acuu techni ue has been de#elo!ed to a!!ly the coating.

a e!late anu)acturers ha#e )ound UV curable coatings o))er outstanding line s!eed and!er)or ance !ro!erties in coating etal stoc%. UV cured coating !ro#ides an eye a!!ealing HglassyHloo% to etal na e!late" and the coated etal can be !ost )or ed e#en at a )il thic%ness u! tothree ils. *!ecial do e and lens loo% can be achie#ed $ith UV coatings u! to 1/>th inch thic%.

?any o) the be#erage co !anies use UV curable in%s )or decoration. In% layers u! to 0.4 il can be

cured $ith UV light at acce!table line s!eeds.

-oatings )or o!tical )ibers

UV curable coatings ha#e been the choice coating technology )or anu)acturing o!tical )ibers since)iber began to be used co ercially in the late 19 0s. + so)t !ri ary and tough secondary coatingare a!!lied in se uence as the glass )iber is dra$n )ro the olten glass !re)or . 'y!ically" UVlights are !ositioned i ediately a)ter the !ri ary coating a!!licator and secondary coatinga!!licator. o$e#er" so e )iber is !roduced by a $et&on&$et coating !rocess in $hich UV lights are

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!ositioned only a)ter the secondary coating a!!licator. In the $et&on&$et !rocess" both the !ri aryand secondary coatings cure si ultaneously. :ine s!eeds exceeding 4"000 )eet/ inute are co onin anu)acturing o!tical )iber. UV curable in%s are used to color code )iber in an o))&line o!eration.Fibers used in and around the city are usually installed in a ribbon con)iguration in $hich se#eralindi#idual )ibers are bound side by side. 'he atrix aterial used to bind the )ibers together is also aUV curable coating.

UV/EB In%s and clear coatings )or gra!hic arts

1. 3))set lithogra!hy

UV/EB curable in%s and coatings o))er se#eral o!tions )or o))set !rinting. 'hese include

;. In% et

3ne o) the a5or obstacles in co erciali(ing UV/EB curable in%5et in%s is the lo$ #iscosityre uire ent )or in%5et !rinting. UV/EB curable )or ulations generally re uire a !ortion o) higholecular $eight oligo er to enhance cured )il adhesion and toughness. 'hese relati#ely higholecular $eight aterials signi)icantly increase coating #iscosity. ,ecent de#elo! ents in !rintheads" based on 2ie(o technology" ha#e ex!anded the #iscosity range )or in%5et !rinting toacco odate UV/EB curable in%5et in%s. UV/EB curable in%5et in%s are a#ailable at #iscosities in the10 to 40 c!s range at 44 degrees -.

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<. Flexo

UV and EB curable in%s are a#ailable )or )lexo !rinting. In% #iscosities range )ro <00 to 400 c!s.3ne o) the ad#antages in !rinting $ith UV/EB curable in%s is su!erior dot gain achie#ed $ith these

in%s o#er sol#ent&based )lexo in%s. 'y!ical line s!eed )or UV in%s used on narro$ $eb label lines is400 to 600 )eet/ inute. Ceb tra!!ing $ith EB curable in%s eli inates the need to change sol#entand can be run at line s!eeds #arying bet$een 1"000 to 1"400 )eet/ inute on )il stoc%.

2o$der coatings

UV !o$der coatings o))er t$o a5or ad#antages o#er con#entional !o$der coatings 1 they do notcure during the elting ste! and ; they elt at lo$er te !eratures than con#entional !o$dercoatings. 'hese t$o ad#antages enable !ost&curing o!erations to be done in&line $ith less s!acere uire ents and at )aster s!eeds than a con#entional !o$der coating line. +!!lied coatingthic%ness can be controlled )ro 1.4 to =.0 ils. -ured )il !ro!erties include excellent sol#ent" salt

s!ray" and stain resistance in addition to excellent substrate adhesion. +!!lications )or UV curable!o$der coatings include etal" !lastic re uires conducti#e !ri er/conducti#e additi#e ediudensity )iberboard ? F " electric otors" auto obile radiator" 2V- )looring" )urniture" gal#ani(edsteel" and engine bloc%s. 'hree&di ensional a!!lications are under de#elo! ent.

*olid I aging

uring the last 14 years" co !anies ha#e been able to ta%e ad#antage o) using UV curable coatingtechnology to dra atically reduce the ti e it ta%es to a%e co !lex !rototy!e de#ices. 'histechni ue" o)ten re)erred to as stereolithogra!hy" uses -+ in)or ation to generate a three&di ensional HbuildH )ile o) the desired !rototy!e. 'he build )ile consists o) a stac% o) thin t$o&

di ensional cross sectional layers that together du!licate the !rototy!e. *o)t$are then uses thisbuild )ile to direct a laser bea in a #at containing a !hoto!oly eri(able li uid. +s the laser traceseach layer o) the !rototy!e" a re!lica o) each layer is )or ed as a !oly eri(ed layer in the #at. Eachslice has a )il thic%ness o) bet$een 0.001 to 0.0;0 inch. 'he !oly eri(ed layer rests on a build!lat)or . 'he build !lat)or is then lo$ered into the #at to a !redeter ined le#el and the!oly eri(ed layer is co#ered $ith )resh uncured coating. 'he laser then traces out the next crosssectional layer o) the !rototy!e and creates a ne$ layer o) !oly eri(ed coating on to! o) the )irstlayer. 'his !rocess o) curing the to! li uid layer and lo$ering the build !lat)or is re!eated until the!rototy!e is du!licated as a hardened resin in the #at o) li uid coating. +t the end o) the !rocess" thebuild !lat)or is raised. 'hen" the du!licated !rototy!e is re o#ed )ro the #at and undergoesadditional !rocessing. 'his ethod o) a%ing !rototy!es is easured in hours instead o) $ee%s

using the con#entional ethod o) a%ing olds.

*a)e andling o) UV/EB -urable -oatings

In general" the acrylates used in UV/EB curable coatings are relati#ely sa)e $hen used as directedon the !roduct ?* *. ?oreo#er" sol#ent&)ree UV/EB curable coatings do not !ose an inhalation!roble under nor al !lant #entilation conditions.

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+crylates are considered to be s%in irritants and s%in sensiti(ers. 'here)ore" as $ith any other li uidche ical" it is i !ortant to !re#ent s%in and eye contact $hen handling UV/EB curable coatings.Cearing che ical resistant glo#es" sa)ety glasses or goggles" and a $or% uni)or or !rotecti#ea!ron are re uired to sa)ely handle UV/EB curable coatings. -lothing soiled $ith acrylates should bere o#ed i ediately to !re#ent s%in contact. Cashing hands routinely $ith lu%e$ar $ater and a

ild soa! is also ad#isable to re o#e any undetected acrylate that ay ha#e co e $ith the s%in.e!ending u!on the situation" $earing a !lastic bootie o#er shoes ay be ad#isable. 'he s%in andeye irritation and sensiti(ation ha(ards are eli inated once the coating is )ully cured. Instructinge !loyees in the sa)e handling o) UV/EB curable coatings should be !art o) an e !loyee&training!rogra .

Chen storing acrylate&based coatings" it is i !ortant to insure the !resence o) air in the container.'he oxygen in air hel!s to !re#ent the li uid coating )ro increasing in #iscosity. -onta ination $ith$ater" acid and base should be a#oided $hen storing cationic curable )or ulations. It is alsoad#isable to chec% the su!!lierJs ?* * )or !ro!er storage te !erature conditions. In general"UV/EB curable coatings should be stored bet$een 60 and >0 degrees F.

+#oid using high shear !u !s !iston and gear $hen trans)erring UV/EB curable coatings. 'he t$oreco ended ty!es o) !u !s )or trans)erring UV/EB curable aterials are a dia!hrag and!eristaltic !u !.

:egal and ,egulatory -onsiderations

+ll !roducts used co ercially ust be co !liant $ith national che ical in#entories. In the United*tates" all co !onents in a co ercially used !roduct ust be listed on the '*-+ -he icalIn#entory. 3ther countries ha#e their #ersion o) '*-+ that ust be )ollo$ed. I) you are a coatingsu!!lier" it is i !ortant to a%e sure you are not anu)acturing or selling your !roduct in a country in

$hich the !roduct in)ringes a #alid !atent. I) you o$n a !atent )or a !roduct you are selling" youshould consider i !le enting a !atent& ar%ing !rogra to axi i(e the e))ecti#eness o) your!atent. I) you are an end user o) a !roduct" you should chec% to a%e sure you are not in)ringing a#alid !atent.

,e)erences

1. -he ical 2ro5ect Fact *heet UV&-urable -oatings )or +lu inu -an 2roduction" 3))ice o)Industrial 'echnologies"Energy E))iciency and ,ene$able Energy" U.*. e!art ent o) Energy" +!ril" ;00;" a#ailable at$$$.oit.doe.go#/nice</)actsheets/coors.!d).

;. 61 Fed. ,eg. ; 1<;" ; 1<< ?ay <0" 1996 .<. 'echnical Bulletin on Ultra#iolet and Electron Bea -ured -oatings" In%s and +dhesi#es" U.*.E2+" -lean +ir 'echnology -enter" uly" ;001" a#ailable at $$$"e!a.go#/ttn/catc/dir1/)u#&eb.!d).=. ational E ission *tandards )or a(ards +ir 2ollutants E* +2 )or *ource -ategory *ur)ace-oating o) ?etal-oil" Bac%ground In)or ation )or Final *tandards" U.*. E2+" ?ay" ;00;" !. 60.4. ational E ission *tandards )or a(ards +ir 2ollutants E* +2 )or *ource -ategory *ur)ace

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-oating o) ?etal-ans" Bac%ground In)or ation )or 2ro!osed *tandards" U.*. E2+" o#e ber" ;00;" !. 9.6. E#aluation o) UV&-urable -oatings )or +lu inu -an 2roduction" ational Industrial/co !etiti#eness 'hroughE))iciency )or the U.*. e!art ent o) Energy" une" 199 !. <> & <9.

. *ee $$$.#alleyair.org.>. *. . ?ihalic K 2. ?ills" ,ad'ech ,e!ort" uly/+ugust" 1999" !. ;6.

*B&UT T E *UT &' eorge 2asternac%" 2h. .r. 2asternac% has a 2h. . in che istry and o))ers ore than <0 years o) extensi#e ,K "anu)acturing" !atent la$" $orld$ide go#ern ent co !liance and anage ent ex!ertise in theche ical industry. + nationally %no$n ex!ert in the )ield o) UV and EB curable coatings" r.2asternac% has been selected to !resent the 'echnical and *a)ety !ortions o) the last )i#e 2ri er*essions held at the ,ad'ech ational -on)erences. e has hands&on laboratory and ,Kanage ent ex!erience in the co erciali(ation o) ore than 40 ne$ !roducts )or a broad rangeo) industrial uses. r. 2asternac% directed a cor!orate technical exchange !rogra bet$een his

United *tates laboratory and o#erseas !artners. e has ore than 64 !ublications. r. 2asternac%de#elo!ed and i !le ented a ulti illion&dollar global !atent !rogra that included $orld$ide!atent en)orce ent. In addition" he created and directed a cor!orate $orld$ide !roduct ?* * andgo#ern ent co !liance !rogra .

-o!yright ?.B. 2asternac% K +ssociates" Inc.?ore in)or ation about ?.B. 2asternac% K +ssociates" Inc.

Disclaimer: While every effort has been made to ensure the accuracy of this publication, it is notintended to provide legal advice as individual situations will differ and should be discussed with anexpert and/or lawyer. For specific technical or legal advice on the information provided and related

topics, please contact the author.