Paperboard Guide

8/10/2019 Paperboard Guide

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2/60Paperboard Guide

Contents 2

Introduction 3

1. Information about Stora Enso andConsumer Boards 4

1.1 Stora Enso in brief 5 1.2 Stora Enso Consumer Boards 6 1.3 Sustainability in packaging 7

2. Paperboard making andpaperboard grades 8

2.1 Paperboard making 9 2.2 Paperboard grades 11

3. Barrier coating 15

4. Paperboard handling recommendations 18

5. Printing methods 19

5.1 Offset printing 21 5.2 Gravure printing 22 5.3 Flexo printing 23 5.4 Inks 24 5.5 Digital printing 25 5.6 Practical printing instructions 26

6. Converting and Finishing 28

6.1 Varnishing 29 6.2 Embossing 31 6.3 Hot-foil stamping 31 6.4 Die-cutting and creasing 32 6.5 Glueing 34 6.6 Lamination 35

7. End uses 36

7.1 Graphical 39 7.2 Beverage and multipack 40

7.3 Chocolate and confectionery 41 7.4 Cigarette 42

7.5 Cosmetics and luxury 43 7.6 Detergents and household 44 7.7 Food 45 7.8 Pharmaceutical 46 7.9 Food Service 47 7.10 Liquid 47

8. Stora Enso Consumer Boards productionand service facilities 48

8.1 Paperboard mills 49 8.2 Extrusion coating plants 51

8.3 Partner services 52

9. Testing methods 53

10. Glossary 57

Contents


3/603 Paperboard Guide

Creating innovative packages and bril-liant graphical products from advancedpaperboard materials is both a scienceand an art. As a rule of thumb, the skyis the limit as to the implementation ofartistic designs or demanding print-ing and nishing effects. However, themore we know about the behaviour ofpaperboard in various rening processesand individual end use environments,the better the result. This Paperboard Guide has beencompiled to that very end to serveour partners and their customers with

accurate information that helps makeexcellence out of the ordinary.

As is characteristic of educationalmaterial, a lot of the subject matterdeals with concepts, denitions, ab-breviations and principles. In additionto explaining the basic vocabulary, theGuide presents an overall picture of thepaper-board world and claries some ofthe key issues related to it.

Introduction

Welcome to the enchanting world of paperboard.

Pasi Ahokas VP, Graphical Boards


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Stora Ensos sales totalled EUR 13.2 billion in 2005.The Group has some 46 000 employees in more than40 countries on ve continents. Stora Enso has an annualproduction capacity of 16.9 million tonnes of paperand board and 7.7 million cubic metres of sawn woodproducts, including 3.3 million cubic metres of value-added products. Stora Ensos shares are listed in Helsinki,Stockholm, and New York.

Stora Enso serves its mainly business-to-business custom -ers through its own global sales and marketing network.

A global presence provides local customer service.Customers include publishers, printing houses, and mer-chants, as well as the packaging, joinery, and construc-tion industries and are mainly concentrated in Europe,North America, and Asia. As Stora Enso moves into the

future, the Group is focusing on expanding its opera-tions in new growth markets in China, South America,and Russia.

The Group has production facilities in Europe,North and South America, and Asia. Modern produc-tion capacity, combined with efcient raw material andenergy sourcing and efcient processes, ensure excellentcontinuity of production.

Stora Enso is committed to sustainability economic,environmental, and social responsibility underpins ourthinking and our approach to every aspect of doing busi-ness. The Group builds accountability into its operationsby being transparent and engaging in open dialoguewith its stakeholders. Group-wide targets and cleargovernance are used to monitor and measure how wellStora Enso performs in terms of sustainability.

1.1 Stora Enso in brief

Information

and Consumer Boards

about Stora Enso

Stora Enso is an integrated paper,packaging, and forest products company,producing publication and ne paper,packaging board, and wood products all areas in which the Group is a globalmarket leader.

5 Stora Enso in Brief

committed tosustainability


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1.2 Stora Enso Consumer Boards

providing packaging solutions worldwide

Fibre-based materials enjoy a strong and well-deservedstatus in the packaging world. Paperboard is smoothand strong, light and bright, versatile and cost-effective.

A generous printing surface and superb print qualitymakes paperboard cartons ideal information carriers andbrand builders. Reliability in high-speed lling lines savesmoney and minimizes production downtime. Renew -able bres also make a particularly well-founded choice

environmentally.

The ultimate challenge, however, lies in using the fullpotential of the material intelligently and innovativelyto create solutions and concepts that will have a com-petitive edge in product protection, material savings,production and logistics costs, trade preference, con-

sumer acceptance, shelf presence or recycling efciency.Such solutions do not materialize out of thin air. Theystem from active interaction with the whole packagingcommunity. And that is where the offering of Stora EnsoConsumer Boards really comes into its own.

We produce a wide selection of paperboards in everycategory and provide the largest variety of polymer coat-ings. We have strong and modern pulp and board millsthat, together with our sales staff and ServiceCentre fa-cilities, ensure consistent quality, fast service and reliabledeliveries. But even more than that, we are committedto vertical innovation in the way we cooperate with ourpartners across the board to promote the efciency andsustainability of bre-based packaging.

Information

and Consumer Boards

about Stora Enso

Liqu id Fre shLiquid Ambient

Stora Enso Consumer Boards 6

Stora Enso Consumer Boards


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Information

and Consumer Boards

about Stora Enso

1.3 Sustainability in packaging

Sustainable development in packaging means solutionsthat satisfy present needs in an optimal way withoutcompromising the ability of future generations to meettheir own needs. Fibre-based boards provide a powerfulmeans of achieving those goals throughout the pack-ages life-cycle. Here are some of the basic issues:

Wood, a renewable and recyclable resource, is the mainraw material in our packaging boards. We apply the prin-ciples of environmental and social responsibility for woodprocurement and sustainable forest management.

Paperboard is produced at an integrated mill, usingmainly renewable energy derived from the wood in thepulping process.

Versatile and light paperboard packages prevent productloss by effectively protecting packed materials against

physical damage, contamination and light. Product information can be printed directly onto the surface of thepaperboard, so no extra labels are needed.

Space-saving designs are particularly economical intransportation. Efcient logistics reduce fuel consump-tion and emissions to the atmosphere.

Paperboard packaging is a valuable resource in itself,with many potential uses. Packaging boards are made

from bres with good strength properties and can berecycled for a number of paper and paperboard grades.In the case of polymer-coated boards, the plastic fractioncan be used for energy production, replacing fossil fuels,or can be recycled when appropriate.

For a more detailed presentation of sustainability in pack-aging, view the multimedia.

7 Sustainability in Packaging


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Paperboard

paperboard grades

making and

Paperboard making and paperboard grades 8


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Paperboard

paperboard grades

making and

2.1 Paperboard Making

The basic principles of paper and paperboard makinghave not changed for more than two thousand years.Fibres gained from timber are evenly distributed inwater. Multiple layers of furnish are applied, one after theother, on a wire. The water is drained from the pulp and

the layers are formed into a strong bre mat. A smoothsurface is achieved by coating and calendering. Theexcellent quality of Stora Enso paperboards is the resultof advanced technology and the use of high-quality rawmaterials.

Raw Materials used for Paperboard Production

Chemical Pulp Wood chips are cooked with appropri-ate chemicals in an aqueous solutionat high temperature and pressure. Theobjective is to dissolve the lignin andseparate the bres intact. The pulp canbe used unbleached or bleached to the

brightness needed.

HardwoodPulp made of deciduous broad-leavedtrees such as birch, oak, beech, aspen oreucalyptus. Characteristic are the short

bres.

SoftwoodPulp produced ofpine, spruce, orother conifers. The

bres are long.

Watermeans of trans-port and solvent.

PigmentsNatural coating pigments and

llers. Ground Calsium Carbonate(GCC) and Kaolin Clay.

Latex Water dispersion of organic binder for the coating pigment.

Components Coating Colourrheology modiers

Sizing Agentssuch as natural resin or syntheticsizes are added to increase strengthand decrease absorbance.

Wet-end Additivesand Retention Aide.g. starch and aluminium sulphate.

Secondary bresare gained from sortedrecovered paper orboard by purifying andsometimes deinking andbleaching.

CTMP(Chemi ThermoMechanical Pulp)

Wood chips are impregnatedwith appropriate chemicals andheated before separating the

bres by a mechanical reningprocess. The pulp is bleachedand washed in several steps.

GroundwoodLogs of debarked softwoodare pressed against a rotatinggrinding stone while water isadded in order to separate the

bres.

Mechanical Pulp

9 Paperboard making and paperboard grades


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Paperboard

paperboard grades

making and

Paperboard ProductionThe picture below illustrates one typical example ofpaperboard machine lay-out.

Wire Section Press Section Pre-Drying Section

Wire Section: The web is formed in the wire section by pumpinga mixture of water and pulp from the headboxes onto the wire. Thewater content is over 99%, which is why this part of a paperboardmachine is also known as the wet end. The water is drained off andthe bres bond together. The individual layers of bre are couched.

An even bre formation is vital to ensure optimum strength, surfacesmoothness and uniformity. After the wire section water content is80%.

Press Section: In the press section, water is removed from the wetweb by mechanical compression in the nips formed by two rolls. Theremoved water is received by a felt. After press section water contentis approximately 60%.

Pre-Drying Section: The paperboard web is further dried by a seriesof steam-heated drying cylinders.

Pre-Drying Section

Glazing Cylinder

Post-Drying Section 1 Coating Section

Post-Drying Section 2Shoe Calender

Glazing Cylinder: The top side of the web can be smoothed bycontact with a Yankee cylinder having a highly polished surface orwith so called shoe calender. Not every paperboard machine hasthese options.

Post-Drying Section 1 and 2: Additional reduction of moisturecontent.

Coating Section: Depending on the quality required, the web canbe coated with one, two or three coating stations per side.

Reeler Section Winding Paperboard Reel

Gloss Calender

Calendering: The smoothing calender further regulates the surfacequality. Depending on the grade, the surface is additionally calend-

ered with the hot surface of the gloss calender.

Winding: The nished paperboard is wound up to a jumbo reelwhich is then rewound into narrower reels and according to customerrequirements, either sent to customers in reels or cut into sheets.


Extrusion coatingFor some end-uses paperboard can be extrusion coated.Extrusion coating is a separate process after the paper-board production. For more information on the barriercoating options see chapter 3.0.


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Paperboard

paperboard grades

making and

2.2 Paperboard Grades

A great variety of grades are commercially available andthe terms used to describe them vary from market tomarket. Below the grade categories are based on bregrades and production technology. Each grade may betailored for many end uses and for individual customerneeds.

Paper and paperboard are made with the same base

technology. Paper provides mainly the printing surface,paperboard both printing surface, stiffness, strength andother properties necessary in packaging and graphic enduses. Usually basis weight, caliper and stiffness are higherthan those of paper and also most of the paperboardgrades are multiply products.

FBB (Folding Boxboard)

A layer or layers made of mechanical pulp is betweenlayers of chemical pulp. Mechanical pulp may bestone-ground wood (GW), pressurized groundwood(PGW), thermo mechanical pulp (TMP) or chemi-ther-momechanical pulp (CTMP). The top layer is bleachedchemical pulp and the reverse layer can be bleached orunbleached chemical pulp. The top and reverse side maybe coated with mineral or synthetic pigments.

SBS (Solid Bleached Sulphate)

Paperboard entirely made of bleached chemical pulp.The top side and reverse may be coated with mineral orsynthetic pigments.

SUB(Solid Unbleached Board) / SUS (Solid UnbleachedSulphate)

Paperboard made mainly of unbleached chemical pulp.To achieve a white surface, it may be coated with miner-al or synthetic pigments, sometimes in combination witha layer of bleached bres under this layer. Some CTMPor recycled bres may partly replace the unbleachedsulphate pulp.

Double / triple coatingBleached chemical pulpBleached mechanical pulpBleached chemical pulp(Coating)

Double / triple coatingBleached chemical pulpBleached chemical pulpBleached chemical pulpSingle/double coating

Double / triple coatingBleached or unbleached chemical pulpUnbleached chemical pulp(mixed with CTMP / recycled bres)

Unbleached chemical pulp(mixed with CTMP / recycled bres)

(Coating)

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Paperboard

paperboard grades

making and


WLC (White Lined Chipboard)

Multi-layer paperboard comprising at least one mid-dle layer of mainly recovered bres. The top layer isbleached virgin chemical pulp or white recovered pulps.Between the top layer and the middle layer(s) there canbe a layer of chemical, mechanical or deinked recycled

bres. The reverse layer can be made from selected recy-cled bres or bleached and / or unbleached virgin bres.The top and reverse side may be coated with mineral orsynthetic pigments.

LPB (Liquid Packaging Board)

Liquid Packaging Boards (LPB) are used for the packag-ing of liquid foods, such as milk or juice. The baseboardmay be either coated or uncoated FBB, SBS or SUB.The paperboard is plastic coated often with PE (Poly-ethylene), high-barrier - or foil-laminated for long-lifebeverages.

Two-sided PE coatingPE CoatingBoardPE Coating

PE coatingBoardBarrier layer PE coating

Double / triple coatingBleached chemical pulp /white recovered pulps

Recovered paper orpaperboard brown / grey

Bleached chemical pulp /any of the pulps above(Coating)


13/6013 Paperboard making and paperboard grades

Denition (DIN 19303) Type Description Pulp Stock

uncoated coated

AZ SBS Cast-coated solid bleached board with white back Fully bleached chemical pulp

AC1 FBB Cast-coated folding boxboard with white back Chemical and mechanical pulp

AC 2 FBB Cast-coated folding boxboard with cream back Chemical and mechanical pulp

UZ GZ SBS Solid bleached board Fully bleached chemical pulp

GN1 SUS /SUB /CNK Solid unbleached board with white back Unbleached chemical pulp

GN4 SUS Solid unbleached board with brown back Unbleached chemical pulp

UC1 GC1 FBB Folding Boxboard with white back Chemical and mechanical pulp

UC2 GC2 FBB Folding Boxboard with cream back Chemical and mechanical pulp

UT1 GT1 WLC White lined chipboard with white back Secondary bres

UT2 GT2 WLC White lined chipboard with cream back Secondary bres

UT4 GT4 WLC White lined chipboard with brown back Secondary bres

UD1 GD1 WLC White lined chipboard high bulk 1,45 cm 3/g Secondary bres

UD2 GD2 WLC White lined chipboard high bulk < 1,45 cm 3/g, > 1,3 cm 3/g Secondary bres

UD3 GD3 WLC White lined chipboard high bulk 1,3 cm 3/g Secondary bres

Overview of Paperboard Nomenclature

According to DIN 19303, any paperboard can bedescribed by a combined code of two letters or twoletters and one gure.

The rst letter describes the type of surface treatment: A = cast-coated G = pigment-coated U = uncoated

The second letter stands for the main furnish: Z = bleached chemical pulp N = unbleached chemical pulp C = mechanical pulp T = secondary-bre pulp with white,

cream or brown reverse D = secondary-bre pulp with grey reverse

Except for the D grades the gure denes the colourof the reverse side: 1 = white 2 = cream

3 = brown

For the D grades, the gure describes the bulkof the paperboard: 1 = 1.45 cm 3/g 2 = < 1.45 cm 3/g, > 1.3 cm 3/g 3 = 1.3 cm 3/g

Paperboard

paperboard grades

making and


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BarrierCoating

Barrier Coating 14


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Polyolen coatings:

High-barrier coatings

Patented Ensobarr high-barrier coatings consist of multi-layer EVOH and/or PA polymer structures. They provideexcellent light, oxygen, humidity and aroma protection.Ensobarr Silver grade has an additional silver-colouredlayer to provide maximum protection against light. Thehigh-barrier coated boards are also greaseproof.

Typical uses: various delicate foods, including chocolate,cereals and dairy products; dry foods, such as candy,savoury and processed snacks, coffee and tea, milkand cocoa powders; liquid products such as juices, softdrinks, green tea, water, soups and desserts, as well aslight-sensitive beverages such as wines and long shelf-lifejuices; non-food products such as liquid detergents and

fabric softeners.

High-barrier coatings:

Special Polymer Coatings

Special coatings can perform both barrier and other functions. Typical examples are PET coatings that provideheat resistance together with excellent grease barrier fea -tures and good WVTR (Water Vapour Transmission Rate)properties. PBT polymers are similar to PET in their func -tions, but enhanced with excellent release properties.

Typical uses: Oven-usable trays and reheatable productpackages, and non-stick trays for bakery products.

Special barrier coatings:

Biopolymer Coatings

Biodegradable coatings are tailor-made polymers provid-ing humidity and oxygen barriers as well as sealability.The coating can be composted into humus in organic

recycling.

Biopolymer coatings:

BarrierCoating

Light

Oxygen

HumidityHeat,peelability

Grease

3

2

1

0

Light

Oxygen


Grease

3

2

1

0

Light

Oxygen


Grease

3

2

1

0

Light

Oxygen


Grease

3

2

1

0

Barrier Coating 16

Performance:1. Moderate 2. Good 3. Excellent


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Paperboard

Recommendations

Handling

Paperboard Handling Recommendations 17


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Paperboard

Recommendations

Handling

4. Paperboard Handling Recommendations

Due to their structure, all boards are living material. Anunwrapped sheet of paperboard reacts with the air veryquickly. Before printing, you must make sure that theinternal relative humidity and temperature of the sheetsare in balance with the conditions of the press room.Large differences in these parameters can lead to prob-lems such as curling of the sheets and slow ink drying.

Make sure that the paperboard is acclimatized to whereit is going to be printed. The necessary time for settlingcan be found on our pallet labels.

Example: If the size (volume) of the pallet is 1 m 3 (1m x 1m x 1m) and the temperature difference be-tween the pallet and the press room is 20C, the settlingtime needs to be 46 hours in the press room.

For paperboard, the ideal humidity of both the ware -house and the press room is 50-55% relative humidityand the ideal temperature 20-23 C.

Increased relative humidity can cause drying and rub-resistance problems in the printed surface. Anotherpossible reason for slow drying may be a shortage of theoxygen that is needed for ink polymerization.

Remove the wrapping just before printing. This willensure even and smooth settling of the pallet. The wrap -ping also protects the sheets from dirt and damage.

pallet m3 Difference in temperature between the press room and pallet

5C 10C 15C 20C 25C 300.3 7 h 14 h 21 h 31 h 43 h 60 h0.4 7 h 17 h 26 h 36 h 41 h 64 h0.6 9 h 20 h 31 h 42 h 55 h 76 h0.7 11 h 21 h 31 h 44 h 58 h 79 h

1 12 h 23 h 33 h 46 h 62 h 87 h2 13 h 24 h 35 h 49 h 66 h 90 h

18 Paperboard Handling Recommendations


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PrintingMethods

Printing Methods 19


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PrintingMethods

5. Printing Methods

The nal print quality is inuenced by many variables,such as paperboard properties, printing press and proc-ess parameters, and ink properties. For optimal results, itis important to understand the interaction between vitalpaperboard properties and the chosen printing process.

This chapter describes the most common printing meth -ods, although the information below focuses mainly

on the sheet-fed offset process, which is the dominantprinting technique for paperboards. The information will

facilitate the processing of our paperboards and enhancethe quality of the print work. Moreover, these guidelinesmay serve as a token of our ongoing endeavours to addour manufacturing experience to the expertise of theprinting and converting industries.

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The dominant printing method is offset, which is dividedinto three different processes:

sheet-fed (sheets) SFO for paper and paperboard heatset web offset (reels) HSWO for paper and

low-grammage paperboard coldset web offset (reels) CSWO for newsprint

Offset printing is based on physicochemical reactionsbetween the ink, fountain solution, printing plate andblanket.

The printing plate is made of aluminium. The plate ischemically treated so that image areas accept greasy ink(oleophilic) and are water-repellent. The non-printingareas are hydrophilic, meaning that they repel ink butaccept fountain solution.

The average thickness of the ink layer carried by theplate is 2-3 m and that of the water layer 1-2 m.

The ink is transferred from the printing plate to the print-ing blanket, then onto the surface of the paperboard.

The structure of the printing blanket is a texture of 2-4layers covered with rubber layers. The blanket has differ-ent hardness levels (70-85 ShoreD), the harder blanketsbeing more durable and meant for higher printingspeeds. By using a soft blanket, better contact with thepaperboard can be achieved. The blanket is not allowedto react with ink solvents during the printing process.

The printing blanket transfers the printing image fromthe printing plate to the surface of the printing material.

The offset inks are very tacky and require high surfacestrength in the print material. The sheet-fed inks dry byabsorption and oxidation, heatset inks by evaporation(aided by dryers). UV (Ultraviolet) offset inks need UVlight to dry by polymerization.

The inking unit transfers an even ink layer to the printingplate, makes the ink uid and exible and keeps it at thecorrect temperature.

The fountain solution forms a thin water layer onnon-printing areas of the printing plate. The pH, hard-ness and conductivity are important properties for the

fountain solution. The pH should be between 4.8 and5.3, hardness between 7 and 15 dH and conductivity50-200 mS/m to achieve the best printing result.

Sheet-fed offset printing unit

Waterless offset (dry offset)

In waterless offset printing, no water is involved in theprinting process.

In the dry offset (waterless offset) process, more tackyinks are used and special printing plates treated withsilicone are needed. The silicone material of the printingplate has a very low surface energy and makes up thenon-printing area of the plate. This material will resistthe ink, provided the inks viscosity is such that it has agreater afnity for itself than it does for the silicone.

5.1 Offset printing

PrintingMethods

- dots are uniformly covered with ink- edges are ragged

Printing Methods 21

Impression cylinder/roller

Offset blanket cylinder

Paper

Lithoplate cylinder

Water rollers

Water

Ink rollers


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- broken shape of dots- missing dots- donut shaped dots

Temperature control of printing inks is very important.The temperature should be stable. The optimum tem-perature range for dry offset inks is narrower than forconventional offset inks. If the temperature is too low,the viscosity of the ink increases, resulting in poor uid -ity/rheology of the ink and inferior ink transfer. In printedareas, this results in picking, ghosting, mottling (uneven -ness), low printed gloss and problems resulting frompoor ink transfer. If the temperature is too high, the inkviscosity decreases, causing some of the ink to be trans-

ferred to the unprinted areas of the printing plate, result -ing in doubling problems (dye toning: weaker ghost dotsnext to true dots whose position is out of register).

The operating temperature ranges for dry offset inks are26-35C for black, 24-31C for cyan, 22-28C for ma-genta and 20-29C for yellow. The exact temperaturesdepend on the manufacturer of the ink and the ambientconditions.

Waterless offset printing is environmentally friendlierdue to the absence of wastewater and residues from IPA(isopropyl alcohol) or additives.

5.2 Gravure printingGravure is used for long print runs on paperboard, mag-azine paper and plastic lms, and for security printing.

The printing ink is transferred from the printing cylindercells to the surface of the printing material.

Gravure printing

The metallic printing cylinder and soft rubber backingroll form the printing nip. The pressure at the printingnip is high to ensure optimal ink transfer.

The most important requirement for the print mate-rial is smoothness to ensure good contact between thepaperboard, the ink and the printing cylinder. Because ofthe high pressure at the printing nip, the compressibilityof the paperboard is also important.

The printing ink is solvent- or water-based with a verylow viscosity level. The inks dry by evaporation in thedrying unit.

PrintingMethods

Image elements are equallyspaced but differ in area andvolume (variable depth andvariable area)


Blade

Ink fountain

Gravurecylinder

Gravure cylinder


22 Printing Methods


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PrintingMethods

The printing ink is transferred by an anilox roll to theprinting plate. The surface of the anilox roll is full ofsmall, engraved cells and extra ink is wiped away byusing an oscillating doctor blade or a chamber doctorblade.

The printing plate is made of photopolymer or rubber.The uplifting parts of the printing plate transfer the ink

from the plate to the printing material.

The soft printing plate and hard steel backing roll formthe printing nip. The pressure at the printing nip shouldbe very light (kiss).

The exo inks are water- or solvent-based with a verylow viscosity level. UV inks can also be used.

Water- and solvent-based inks dry by evaporation in adrying unit that normally follows each printing unit. UVinks need UV light to dry by polymerization.

The surface energy plays an important role in exoprinting. The surface energy should increase in printingorder (lower for ink than for printing material) to ensureoptimal ink transfer and adhesion.

Flexo printing is mainly used for printing on exiblepackaging, labels, paperboard and uting board,plastic bags and newsprint.

- ink is pressed to edges- shadow in the edge of text

Flexo printing

Impression cylinder (hard)

Printing plate (soft)

Elastic printing plate withraised image elements

Printing substrate

Aniloxroller

Ink supply

(Chambered doctorblade system)

Inked up image elementCells of the aniloxroller lled with ink

5.3 Flexo printing

Printing Methods 23


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The main components in a printing ink are:

Pigment that creates the colour and colourstrength and gives the ink its optical properties

Binder that binds the pigments into the printingmaterial and affects ink drying and ink gloss

Solvent that adjusts ink viscosity and has an effect on ink setting and drying. The solvent dissolvesthe binder

Additives (dryer, wax, antiskinning agent, anti- foaming agent and surfactants/exo, gravure)

Sheet-fed offset inks dry by oxidation + absorption andheatset offset inks dry by evaporation.

Offset UV inks dry by polymerization. The ink containsphoto initiators that absorb UV emission. The ink mono-mer has to react with UV emission. Drying progressesthrough the ink layer from top to bottom and is depend-ent on ink layer thickness and ink type (dark or light inkshade).

Offset UV inks are slightly tackier than the conventionalinks, which means that the paperboard needs a higherdegree of picking resistance. No odour or taint problemsnormally occur with UV inks if the drying capacity andtime are optimal. The UV-printed surface is now ready

for further processing.

Flexo and gravure inks can be solvent- or water-basedand both inks dry by evaporation.

Metallic inks for offset

The amount of metal pigment in silver inks is 25-30%and in gold metallic inks up to 50%. The metals usedin gold inks are copper and zinc. The gold colour shade(copper red to greenish yellow) is dependent on theproportions of copper and zinc. Aluminium is used insilver inks.

The platy metal pigments are produced using the ballmill process (gold and silver) or the foil process (silver).The particle size of the metallic pigment is larger thanthat of conventional ink pigments.

All metallic inks have good coverage. The metallic inkdries through absorption and oxidation. The setting of

the ink does not differ from conventional inks. Whenmetallic inks are used, the fountain solution can be thesame kind as for conventional inks.

The adhesion of metallic inks to the printed base isweaker due to the lower binder amount and higher pig-ment amount in the ink. However, these are known factswhen using metallic inks, and any problems are causedby the inks, not by the paperboard to be printed.

If the base board is very rough or has very high poros -ity, it should be sealed before printing with metallic inks.The technique known as underprinting can also be used.Underprinting with yellow, red or orange ink can beused under gold ink, and cyan ink under silver inks. Theshade of the ink will remain unchanged and the rub-offresistance will be improved.

The best paperboard grade for metallic printing is pro-duced in neutral or alkali processes to avoid ink shadedifferences. Printing with metallic inks is best done in thelast printing unit.

The rub resistance of metallic inks is lower than withconventional inks but can be improved by varnishing theprinted surface.

A typical procedure when using metallicinks is as follows:

metallic ink + varnish

sealing of base board + metallic ink + varnish(when the base board is very rough)

underprinting of base board + metallic ink +varnish (shade of ink and rub-resistancewill be better)

The adhesion of varnish to the surface of the metallic inklayer is poor, partly because the ink layer is slippery. Themetallic ink should not contain wax or at any rate aslittle as possible. The ink layer should be thoroughly drybefore varnishing, to improve adhesion. The amount ofvarnish used should also be as low as possible.

The best varnishing process for a metallic ink layer is:metallic ink + water-based varnish + UV varnish.

5.4 Inks

PrintingMethods

24 Printing Methods


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PrintingMethods

5.5 Digital Printing

Traditional and Digital Production Printing Technologies

Page description le

Ripping (Raster Image Processing)

Film processing

Plate making Plate/master manufacturing

Printing using a non-variable master

Offset, Gravure, Flexo

ElectrophotographyInkjet

ElectrocoagulationIonography

Magnetography

Computer to lm Computer to plate/master Computer to plate

on pressComputer to press

Digital Printing

A digital printing system can be dened as a system thatprints images directly from ripped information withouta static master, so that every consecutive print can bedifferent. Until recently, electrophotography was the onlytechnology used in production-type colour digital print -ing machines, but new solutions for production-speeddigital colour printing are being developed, based ontechnologies such as ink-jet and electrocoagulation.

Digital printing is gradually entering the eld of con-sumer goods packaging. Promising new technologiesare being discovered and existing technologies are beingrened. Here, two of the most common digital print-ing methods are discussed briey and some commentsare given regarding the special requirements for eachmethod.

Electrophotography

Paperboard grades work satisfactorily in a variety ofsheet- or web-fed electrophotographic production ma-

chines. Either direct or indirect dry toner, or alternativelyindirect liquid toner, can be used. Machine suppliers inthe dry toner category are Punch Graphix (Xeikon), Xer-ox (DocuColor, iGen3) and e.g. Kodak (NexPress), and inthe liquid toner category, Hewlett-Packard (Indigo).

In general, it can be said that paperboard runs better indry toner machines in which either indirect or single-stepdirect toner transfer is used and the path for the boardinside the printing machine is as straight as possible.Most production printing machines are included in thiscategory. More problems can arise with some home,small ofce or network printers in which toner is trans -

ferred to the board in several separate steps and the path for the board is not as straight. In this category, compat -ibility should be evaluated in each separate case.

For the HP Indigo press (liquid toner), the board surfaceneeds to be treated with primer prior to printing.The treatment can be applied with a exographic coat-ing or printing unit or with an offset printing machine.The primer solution should be used as received. Thetreatment lasts for 2-3 months. Excessively high primerconcentrations reduce the durability and impair liquidtoner compatibility, which may cause yellowing.

Inkjet

Paperboards are highly suitable for printing with UVinkjet inks and for one-colour inkjet printing (black). Thecompatibility with other inkjet inks depends on the inkcomposition and should be evaluated case by case.

Printing Methods 25

One classication of the traditional and digital production printing technologies.


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PrintingMethods

Grain direction (Machine direction)

The direction in which most bers lay in a nished sheetof paperboard is referred to as grain. Fibers ow parallelto the direction in which the paperboard travels on theboard machine during manufacture.

The end use of the product must be taken into consider-ation when choosing the grain direction. It is importantto know how the end product will be used and whatrequirements are related to its function. For example, thedirection of a score or fold or the required sturdiness ofthe end product should determine the grain directionwhen the sheets are ordered.

Another important factor for choosing grain direction isthe printing press. Almost without exception, the run-nability of the paperboard is better if printed with thegrain direction parallel to the cylinders. The paperboardis more exible in the sharp curves of the press andproblems can be avoided even at high speeds. This fac-tor becomes even more important when the grammageof the paperboard is higher.

Moisture

Remember also that the moisture applied in the pressincreases the dimensions of the sheet. Because of thestructure of the paperboard, the bres generally expandmore in diameter than in length. It is obvious that if thegrain direction of the sheet is the same as the directionof print, a register problem can occur. The likelihood ofthis problem occurring is greater if large formats are tobe printed with a very precise register. To avoid suchproblems, the orientation of the sheet should be plannedby taking into consideration both the end product andthe printing press.

Printing Methods 27


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Converting

Converting and Finishing 28

and Finishing


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6. Converting and Finishing

Paperboard packaging offers marketers and

their designers an incomparable creativemedium. This is important when it comesto communication, positioning and branding.A strong construction accepts attention-

grabbing embossing without cracks or breaksand a polished nish melds with foils andholograms for vibrancy and depth. The skillfuluse of these printing enhancements inpaperboard design helps to attract consumersand often adds value to the products.

6.1. Varnishing

Varnishing improves the visual appearance of the printedsurface. Varnishes may be matt or glossy. Spot-varnish-ing can also be used to highlight certain areas and makethem more prominent.

The varnish should be resistant to mechanical rubbingand solvents. A glossy varnish lowers the friction coef-

cient (COF) of the paperboard which should be highenough in order to secure good runnability of the pa-perboard in the following converting process. Normallywhen having matt varnish the COF level is high.

The nal gloss level of the varnished surface is depen-dent on paperboard properties, the thickness of thevarnish layer and the chemistry of the varnish used. Ifthe pores in the coating layer are small, the varnish hasdifculty penetrating into the coating layer and tends toremain on the surface.

If the surface is very rough, two varnish layers areneeded; the rst one closes the surface and the secondone smoothes out the roughness.

Solvents in the varnish should not react with the coatingbinder or the ink binder, since such a reaction may resultin softening of the varnished layer.

Yellowing of the varnished layer can be prevented bychoosing the right binder system for the varnish. Varnish-ing will improve the rub-resistance of the printed surface.

Varnishing can be carried out by using an ink unit (offsetvarnish), online varnish unit (exo unit for water-basedvarnish) or a separate varnish unit. Glueing should becarried out on unvarnished areas.

On-line varnishing can be divided intothree main methods:

Offset varnish composed like offset inks, but without pigment

1-2 g/m 2 as dry approximately 75% solid content

chemical drying (oxidation)

Water-based varnish approximately 40-50% solids acryl dispersion

2-5 g/m 2 as dry physical drying (IR, air => evaporation +

penetration)

UV varnish dries by UV radiation

3-8 g/m 2 as dry virtually the entire coating substance polymerizes

into a solid lm

29 Converting and Finishing

Convertingand Finishing


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The advantages and disadvantages of each method are as follows:

+ processed like ink,+ easy to do spot varnishing,+ good moisture protection

- slow drying,- thin layer,- risk of yellowing,- requires powdering,- low gloss,- odour and taste problems may occur

Offset varnish

+ good gloss+ very good abrasion resistance+ fast drying+ little or no set-off powder needed+ high piling stability+ no yellowing+ neutral odour

(dependent on drying conditions)

- spot application more complicated- risk of sheet stretch or shrinkage with lower

grammages due to the high water content- smearing because of too high varnish amount

or too effective drying power

Water-based varnish

+ processed like ink+ easy to do spot varnishing+ good moisture protection

- slow drying- thin layer - risk of yellowing- requires powdering- low gloss- odour and taint problems may occur

Offset varnish

+ the highest gloss+ very hard and resistant+ instantly dry

+ no set-off powder needed+ very high abrasion resistance

- high cost of varnish and energy- not totally odourless

(dependent on drying conditions)

- difcult to process online with conventionalinks (-> adhesion problems)

- yellowing of varnish over time (can be avoidedby using waterbased varnish as primer andincreasing the viscosity of UV varnish)

- varnish may irritate eyes and skin

UV varnish

If UV coating is applied over conventional offset inks, the inksurface must be absolutely dry before coating, and/or the

inks must be carefully selected. Otherwise, the result may be

a lower coating gloss or aking of the coated surface.




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6.2 Embossing

Embossing is done to emphasize printed area or printimpression or even unprinted surface.

Required paperboard properties,if all other properties are the same, then

chemical bre is better than mechanical bre long bres are better than short bres higher moisture is a benet (inhibits cracking) thick paperboard is better than thin strength properties, especially bursting strength,

are important the coating should be exible to avoid cracking multi-layer boards are better than single-layer

boards

Although a bulky paperboard might seem easier toemboss, the aim is usually to achieve a certain height sothat the embossing is more pronounced. A bulky paper-

board will respond in a more spongy way. High-densityboards give more pronounced embossing (at the sametool height).

The embossing machine must be correctly adjusted forthe paperboard grade to be processed.

Hot-foil is a technique using very thin aluminium foil ina variety of metallic colours, such as red, blue, silver orgold. The metallic foil is (loosely) xed to a carrier lm. Atool bearing the image to be hot-foiled strikes this web.Through heat and pressure, the image is transferred tothe paperboard.

Care should be taken when applying hot-foil stampingon varnished paperboard. For best results the foil needsto adhere strongly to the substrate. The presence of anykind of debris or dirt will have a negative inuence onthe end result. The printing and coating therefore needto be awless and adhere strongly to the paperboard.


6.3 Hot-foil Stamping



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6.4 Die-cutting and creasing

Introduction

Characteristics differ between different types of paper-boards, such as solid bleached paperboard (SBS), foldingboxboard (FBB) or white lined chipboard (WLC). Allgrades can be cut and creased, but to obtain the bestresult for each application it is important to ne-tunethe treatment. The operating window of die-cutting andcreasing varies according to the type of paperboard andits individual properties.

It is true of all paperboard types that results differdepending on the grain direction, moisture content,thickness, and the amount and type of surface treatment(pigment, plastic, foil, etc.). Moisture content and thick-ness are the most important factors. Tool life will also beaffected by the paperboard type chosen.

For cutting and creasing, there are basically two meth-ods in use: Rotary or Flat-bed. These different methodsplace different demands on the paperboard. The maindifference between them is:

- In rotary cutting, the knife does not meet theanvil. There is a gap of some 5 microns.

- In at-bed cutting, the knife should just touchthe counter plate for best results.

In addition, at-bed cutting can be performed either in-

line or off-line. All of these variables will to some extentplace different demands on the paperboard. For rotarycutting, the web must stick together, rather than fallapart, until the blanks enter the splitter/collector/stacker.

At the same time, clean cuts are desired. This can beachieved by using specially adapted qualities, but speedof the die-cutting equipment is of course also important.

In off-line at-bed cutting, almost the opposite couldbe said to be true. While clean cuts are still desired, thepaperboard should separate easily in the puncher. The

following description mainly focuses on at-bed cutting.

Die-cutting

A good cut should be clean and free from loose bresand particles.

The most important strength properties of the paper-board are tear and tensile strength. These propertiesdiffer between different paperboard types and the die-cutting process has to be adjusted according to thoseproperties.

The correct moisture content is essential for both run-nability and quality during the die-cutting process. Toohigh a level will make the paperboard stronger, tougherand more difcult to cut. Too low a moisture level willmake the paperboard more brittle and difcult to trans-

fer, and may cause dusting. Difculties in cutting may becaused by the paperboard thickness, moisture variationor tool wear and adjustments. It is important to controlthe climate to keep the moisture content unchanged.Controlled climate helps to achieve a precise registerbetween the work stages.

If the cutting knives are sharp and meet the counter diecorrectly, the cutting occurs as desired. A problem mayoccur if the sheet moves during the process. This is oftendue to incorrect rubbering and results in aking and pre-mature tearing of the back layer of the paperboard. Thisis observable as a torn area next to the cut. Damage willalso occur to the knife if it presses too heavily against themetal plate. The knife wears and becomes blunt, leading

to dust and hairy-cut edges.

Plastic-coated or laminated products with an extra toughlayer (for instance PET) should preferably be die-cut fromthe plastic-coated side.

Creasing

A crease forms when paperboard is pressed into a groovewith a rule. This causes a plastic deformation in the pa-perboard, allowing the paperboard to fold easily withoutcracking. A good crease is sufciently deep and narrowto enable precise folding. The main factor for setting theadjustments is the thickness of the paperboard. The typeof the paperboard is also important. Obviously the pres-sure of the die-cutter also affects the creasing.




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During creasing, the paperboard is weakened in well-dened folding lines, which then act as hinges for foldingpackaging and graphical products. Creasing is carriedout by using a thin strip of steel with a round smoothedge and an accurately cut groove in a thin hard mate -rial known as the counter plate. The creasing rule pushesthe paperboard into the groove of the counter plate,located under the paperboard, creating a permanentcrease.

A good, functional fold occurs when the paperboarddelaminates in the crease into as many thin, undamagedlayers as possible. Ply bond strength must be a compro-mise, so that delamination occurs easily in a crease whilethe structure holds together in other areas.

Thicker boards require a wider rule and groove. Bulkyboards are easy to crease. Creasing requires a exiblecoating and strong surface layers. The bre composi-tion and number of layers are important. A multilayerstructure in creasing is desirable. Because thick materialcannot fold without breaking the structure, the brelayers delaminate in a crease. The bonding between thelayers weakens in creasing, causing them to loosen fromeach other more easily in folding.

The creasability properties depend on the bre orienta -tion. A crease in the machine direction usually has worse

folding properties, because the stiffness is lower in thecross-bre direction. Stable moisture content is impor-tant, because dry paperboard can crack more easily,while moist paperboard has a lower stiffness, resulting indifculties with delamination.

The creasing properties can also be analyzed by makinga creasing window. At laboratory scale, the Marbachequipment is used by changing the groove width anddepth, blade/rule width and the penetration of the creas-ing rule into the groove. The bending forces of creasesare measured. The creases should have certain stiffnessafter bending in MD (machine direction), 45-60% andin CD (cross direction), 55-65%.

A visual judgment of creases is also made. If the paper-board has a large operating window, the creasability isgood.

In general, plastic surface layers improve the creasability,because they have very good elongation before theybreak and tend to reduce the risk of surface cracking inthe creases, compared with plain paperboard.

a = creasing groove width

b = creasing groove depthc = board thicknessd = creasing rule tip thicknesse = creasing rule height

f = thickness of groove bottom

creasing counter part

creasing plate

c

d

e

a

f

b

Creasing




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6.5 Glueing

Side seam or point glueing is often the nal operation inthe carton-making process.

The most common glue types used for packaging pur-poses are waterbased dispersion and hot-melt glues. Set-ting of the glues proceeds by chemical reaction, coolingdown or reduction of solvent.

The glue can be applied using a glue wheel/disk or anozzle system. Water-based glues are applied using bothsystems, while hot-melt glue is applied by nozzles.

When the delamination (breakdown of the seam) occursin the bre layer, the seam is acceptable assuming the in-ternal strength of the paperboard is on acceptable level.If it breaks in the coating layer, there may be a problemduring use. Delamination in the glue layer is a theoreticalpossibility.

The smoothness and porosity of the paperboard surfacehave an effect on the mechanical adhesion of the glue.The glue should be anchored to the paperboard surface.The absorption of the top and reverse layers must not betoo different since this would result in penetration of theglue mostly to the highly absorbent side. The glue mustwet the surfaces properly. For printed and varnished sur-

faces, the seam areas are often devoid of ink and varnishto assist adhesion. It is important to correctly adjust theglueing machine settings to the most suitable open time,compression time and force.

Normally the glues are water-based dispersions of poly-vinyl acetate (PVAc). The most important parameters forglueability are the paperboard and the glue type. Surfaceenergy and smoothness play an important role. Thesurface energy of the paperboard surface must be higherthan that of the glue to ensure good adhesion.

With plastic-coated surfaces, the corona treatment isused to increase the surface energy of the surface. Thelower limit for surface energy of the paperboard surfaceseems to be 38 mN/m anything lower may causeproblems.

The amount of glue applied is dependent on the paper-board and glue types varying with the glues viscosity

for example as well as on the application system (diskor nozzle).

The glue dries as the water penetrates into the paper-board surface. Penetration is dependent on the moistureand porosity of the paperboard surface. A portion of theglue itself should also penetrate into the paperboard.The recommended penetration depth is 1-3 times the

bre diameter.

Hot-melt glues are used to glue materials with a lowporosity level (plastic coatings and metallic laminates) orin processes that require short setting time of the glue(e.g. in-line glueing in packaging machines). Hot-meltglue contains resin (affecting adhesion), wax (creating asuitable rheology for the melted glue) and polymer (forcohesion). Hot-melt glue is melted and applied to thesurface at a temperature of 120-200C. When glueingplastic-coated board, the glue must be so hot that it willmelt the plastic to some degree. Care should be takenwhen using hot-melt glues in cold surroundings or undercold conditions.




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6.6 Lamination

It is to some degree incorrect to talk about lamination asa component of nishing. Paperboard is often bought bya converter and laminated, then sold to a printer. If thisis the case, there are basically two main applications forlamination. Both of them typically involve paperboard inreels:

Lamination of polypropylene, aluminium foil or

metallized polyester lm onto a paperboard Lamination of one or more boards to a core-webof paperboard, foam or similar

The idea of the rst process is often to give a luxuriouslook after printing on the pack. The other application ismore typically intended to produce a display paperboard

for advertising purposes. In this second lamination proc-ess, two or more webs are glued and pressed togetherto obtain a paperboard grade with a higher grammagelevel. As described above, a centre layer of some type isoften included to give a thick product.

The lamination may be:

wax lamination (molten wax is applied to the paperboard surface) glue lamination (two or more webs are glued together) - wet lamination - dry lamination - solventless lamination extrusion lamination

hot melt

Wax or resin-modied wax is used as a hot-melt adhesivein wax lamination. The wax is heated, applied to thesurface and cooled.

In wet lamination, one of the webs must be porous toensure absorption of the solvent, while the other webmay be porous material, aluminium foil or plastic web.

In dry lamination, the glue layer is dried after applica-tion. Dry lamination can be carried out by hot lamina-tion. The dried glue layer is sticky at high temperaturesafter emerging from a drying unit. Extrusion and hot-melt lamination are hot lamination processes.

No solvents and no drying are used in solventless lami-nation. The adhesives are 100% solid materials, used insingle-component or two-component systems.

The glue in wet lamination is normally water-based PVAcglue (solid content about 50%). The glue dries throughabsorption of the water by the paperboard surface. Nodrying unit is needed.

It is recommended that the paperboard be sheet-cut on-line just after the lamination to avoid curling problems.

It is also important that the webs to be glued togetherhave similar caliper and grammage proles. Smooth-ness of the paperboard is often very important in theseprocesses. Other factors, such as the glue, will also affectthe end result, but a smooth paperboard has a higherchance of delivering the desired result.

The paperboard surface must be sufciently absorbent toensure the penetration of the glue solvent.

Paperboard can also be glued onto a medium (otherpaperboard, foam, etc.) as sheets. This is normally doneafter printing and the process is known as pasting orpaper-lining. In other words, the process is different butthe end result may look similar.




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End uses

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End uses

7. End uses

Stora Enso Consumer Boards is the market leader in its eld. We produce a wide selection of premium boards inevery category and provide the largest variety of barriercoatings.

Top-quality materials and innovative solutions opti-mize the performance of each individual package in itsparticular user environment and marketing situation.Consumer Boards offering is based on end-use orientedbusiness competence, backed up by innovation and lo-gistics support through our InnoCentre facility and otherpartner services.

For the brand owner, designer, converter or printer, thesuperiority of paperboard as such is not the heart of thematter. The packaging requirements for luxury cosmeticsare quite unlike those for oven-to-table frozen foods. Itis a question of nding the combination of paperboardproperties, grade and grammage that will optimize theperformance of each individual package, whether therequirements are superior stiffness, creasability, odourand taint neutrality, ageing resistance or superior hot foilstamping.

Product NamesBeverage &Multipack

Chocolate &Confectionery Cigarette

Cosmetics & Luxury

Detergent &Household

Aurocard

Chromocard

CKB

Cosmocart T

Cupforma

Ensocard

Ensocoat

Ensogloss

Koppargloss

Kopparprint

Kopparwhite

Microliner

Natura

Neocart

Performa

Printocart

Tambrite

Tamfold

Tamwhite

Trayforma

Triplex Blanco

Triplex GrisTriplex Madera

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End uses

End uses 38

Understanding the customers business is more thana ubiquitous business phrase. It is the most importantsingle catalyst behind innovative packaging solutionsand proactive partner service. Therefore, the organiza-tion of Stora Enso Consumer Boards is based on the Busi-ness Segment Management principle, which combinesproduction efciency and product streamlining withend-user-driven business concepts.

All our customers are served by dedicated teams. Themajor end uses served by Stora Enso Consumer Boardsare presented below. By clicking on a specic product inthe table, you can download the latest product specica-tions (requires internet connection). You can also accessthe same information by going directly to ConsumerBoards website a t www.storaenso.com/consumerboards.

Product Names Food Food Service Graphical Liquid Media Pharmaceutical

Aurocard

Chromocard

CKB

Cosmocart T

Cupforma

Ensocard

Ensocoat

Ensogloss

Koppargloss

Kopparprint

Kopparwhite

Microliner

Natura

Neocart

Performa

Printocart

Tambrite

Tamfold

Tamwhite

Trayforma

Triplex Blanco

Triplex GrisTriplex Madera


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End uses

7.1 Graphical

Working with the graphical industry is a unique experi-ence. You enter an environment where the printers ex-acting professionalism is matched only by the designersboundless imagination in creating ever new solutions tocapture the interest and acceptance of the target audi-ence.

More strength and durabilityStora Ensos graphical boards are made by combiningvarious pulps into multilayer constructions in order toutilize the best properties of individual pulps. This tech-nology gives the boards their sturdy and rigid structure,unattainable in corresponding wood-free coated papers.

As a result, our graphical boards have precisely the rightstrength and stiffness for optimal performance during

the printing and subsequent nishing stages. Sturdyboards also give superior durability in nal use.

This excellent performance is fully compatible with im-proved economy. Compared with alternative solutions,Stora Enso Graphical Boards produces a nal productwith considerably less total weight, resulting in moreproducts from less raw material.

Smooth and efcient nishingOur graphical boards are fully compatible with the mate-rial requirements of various nishing methods. They aresuited to varnishing treatments, as well as die-cutting,embossing and creasing.

Wide spectrum of paperboard optionsStora Enso offers a comprehensive range of products forthe graphical industry, from WLC (white-lined chip -board) through FBB (folding boxboards) and advancedmultilayer CTMP (chemi-thermomechanical pulp) boardsto SBS (solid bleached sulphate) boards. Whatever theapplication, there is an optimal choice available, de -signed for the best in smoothness and brightness, print-ability and runnability, and consistent high quality frombatch to batch.

Applications

End uses of Stora Enso Graphical Boards

Covers for magazines, books, brochures, annual reports, maps, notepads, and manuals

Cards : greeting cards, postcards, collecting cards,recipe cards

Media : audio and video CD/DVD packs, displayboards, tickets and tags, calendars, folders

Backed up by ServiceCentres with high sheeting capacityand available via an active network of specialized mer-chants, Stora Enso graphical boards are fully equippedto meet the demands of todays fast-moving and rapidlydeveloping graphical industry.

For more information, visit our dedicated site atwww.storaenso.com/graphical.

39 End uses


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End uses

7.2 Beverage and Multipack

Packaging BeveragesThe basic functions of packaging to protect, distrib-ute, inform, attract and sell also apply to beverageproducts. However, the world of beverages is unique inits abundance and variety of products, with the most ex-clusive liquor brands, backed by hundreds of years of his-tory, coexisting with fashionable sports tonics launchedonly yesterday. Paperboard cartons in beverages packag-ing offer a unique combination of brilliant imaging qual-ity, functionality, versatility and cost-effectiveness.

ApplicationsStora Ensos beverage and multipack boards are used forsecondary packaging in various constructions and set-ups, of which the mainstream variants are:

Solid cartons made of high-caliper paperboard Laminated combinations using top liners and

stiffeners Litho lamination to a single/double face

corrugated base

Foil or metallized lm lamination is employed in a largeportion of applications, especially for premium brands.

Beverage cartonsTypical product groups for single-pack cartons are whis -ky, spirits, liqueurs, wine and champagne. In individualapplications, elaborate graphics and nishing treatments(embossing, hot foil stamping, spot varnishing, etc.)often play a major role.

Solid cartons are used for all principal product groups ofalcoholic beverages, while laminated and litho laminatedcartons are predominantly used for cognacs, cham-pagnes and wines.

Bag-in-box applications containing up to 3 liters of winehave quickly captured a large share of sales, especiallyin the low and medium-priced categories. The basic

construction has great potential for further renementand new designs.

MultipacksBeer multipacks have rmly established themselves asjust the tool to attract supermarket buyers and securemaximum turnover from minimum space. That, how-ever, is not the whole picture. Adaptable to individualneeds, distribution methods and marketing strategies,multipacks work for a multitude of products and mar-kets. The eye-catching pack is light and strong, and easyto buy, carry, open and recycle.

The suitability of paperboard for innovative constructionsand novel packaging concepts is a major marketing as-set, evident in such bestsellers as multipacks for beer andliquor and ingenious bag-in-box wine packages.

A generous printing area and excellent full-colour qualitymake paperboard cartons both a global branding tooland a superb vehicle for communication, able to createenhanced shelf presence and long-term customer loyalty.More important still, paperboard cartons offer a wealth

of options for promotional uses and segmentation,localization and testing purposes.

The crucial factor is to know what paperboard packagingcan do and how to initiate the innovative process.

To learn more about how Stora Enso does this, accessthe Partner Services section at our website.

To nd clear answers to a host of industry-specic pack-aging issues visi t www.storaenso.com/beverage.

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End uses

41 End uses

7.3 Chocolate and Confectionery

A box of assorted chocolates is more than a verypractical container. It is a signal, a promise, a personalmessage. No wonder, then, that the package is madeof bre-based paperboard a material that combinesrational functionality with seductive charm.

ApplicationsPackaging solutions based on Stora Ensos chocolateand confectionery packaging boards come in a varietyof innovative forms, designs and sizes, made possible bythe materials universal applicability to a whole range ofconverting, printing, nishing and lling methods andtechniques, as well as a number of advanced barriercoating options. Every individual packaging project sets its own demands.

As a rule of thumb, paperboard properties that play acrucial part in the selection process include:

organoleptic performance for maximum safetyand user satisfaction

optical properties and print quality for optimumshelf presence and brand differentiation

convertibility and runnability for trouble-free pro duction

per-unit cost-efciency for protable packaging ofrelatively low-priced products.

Odour and Taint PerformanceThe sensoric safety of Stora Enso packaging boards restson four pillars:

purity of the baseboards barrier properties of proprietary polymer coatings track record over many years in-house testing, research and development

Purity, Cleanliness, Homogenous QualityThe core segment of Stora Enso chocolate and confec-tionery boards comprises SBS brands produced frompure pulp, as well as a range of boards with CTMPadded for extra strength and yield and the traditionalFBB grades. The choice is extended by the WLC rangemade of recycled bres, elaborately rened and tested

for use in demanding food packaging applications.

Polymer CoatingsStora Enso baseboards coated with proprietary barriersubstances such as PE, PET and High Barrier polymerspreserve the original avour of the product and provideprotection against undesirable effects caused by light,oxygen, humidity or grease.

Matching the most suitable baseboard with the properbarrier coating is a perfect way of maintaining superiorproduct quality and prolonging shelf-life.

For consultation on the planning and implementation

of your own packaging projects, please contact us. Also,our dedicated Internet site offers a comprehensive viewof packaging based on innovative use of bre-basedmaterials. For more information visitwww.storaenso.com/chocolate.


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End uses

End uses 42

7.4 Cigarette

Stora Enso Cigarette Boards offers a wide and cost-effec-tive range of tobacco-packaging solutions. The prod-uct offering includes FBB (Folding Boxboard), CTMP(chemi-thermomechanical pulp) and SBS (Solid BleachedSulphate) options to meet all needs. The wide selectionprovides the right board chooice for the desired position-ing of an individual cigarette brand.

Just-in-time deliveries to printers are secured by fourhighly efcient mills in three countries. The services arebacked up by various R&D projects which support brandowners and printers to create superior product designsand applications.

Finding an optimal board material is facilitated whenall of the options can be obtained from a single source

a major benet to customers. A strong partnershipbetween brand owners, printers and Stora Enso enablesthe most cost-efcient solutions to be found and appliedin all areas of the value chain.


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End uses

43 End uses

7.5 Cosmetics and Luxury

Finding an optimal carton material for packaging cos-metics and perfumes is a demanding task where generalrules of thumb are not easy to nd. However, some ofthe key points are listed below for easy reference in orderto ensure that the package fulls its major functions protecting the contents throughout the supply chain,attracting potential customers and building distinctivebrand images.

Strength and structure for maximum protection Ability to withstand mechanical stress vibrations,impacts, blows and bumps is an absolute necessity forcosmetics cartons. The inner structure of the materialmust be such that the various layers of the paperboarddo not become delaminated under any circumstances.For perfume cartons, on which solid printing, heavy tintsand colourful graphics are often used, the paperboardsstructure must provide excellent smoothness as well as

superior cracking resistance at the fold.

High whiteness for superb visual imageHigh whiteness ensures good contrast in printing im-perative for top-quality results. Furthermore, whitenessassociates strongly with desired product features suchas purity and cleanliness. If the package design employslarge unprinted areas, high whiteness of the paperboardbecomes all the more important.

A signicant feature relating to whiteness is the paper-boards ability to withstand UV radiation without yellow-ing. This is a vital consideration, especially if the carton isto be exposed to sunlight for extended periods.

Full choice of printing and nishing optionsThe quality of the carton must mirror or even enhancethe quality of the contents. Printing techniques shouldinclude offset, exo and gravure. Suitability for digitalprinting is also rapidly gaining weight.

More important still is the possibility to use a wholerange of nishing treatments and special effects, such aspearlescent pigment printing, satin UV varnish, glossyhot-foil stamping, positive blind embossing, or lasercutting. Depending on the design, the visual appearanceof the paperboards reverse side and its printability canalso be decisive factors, taking into consideration thaton cosmetics cartons there is usually a need for a lot ofproduct information.

Odour neutralityThe carton must be very neutral in its organoleptic prop-

erties to ensure that, even after extended storage, noundesired odours will be emitted from the paperboard.Only the desired fragrances, those of the product itself,must be there for the consumer to enjoy.

For more information visit our dedicated site atwww.storaenso.com/cosmetics.


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7.6 Detergents and Household

Packaging solutions must serve many ends. The producton the shelf must be highly visible and representativeand also communicate high quality. At the same time,it is important to produce ecologically sound packagingwithout sacricing such vital functions as product safetyand user convenience. Paperboard is unique in its abilityto satisfy these conicting requirements. Paperboardcartons are lightweight and strong, functional, eye-catching and as cost-efcient in production as they are inrecycling.

Stora Enso is the worlds leading producer of packagingpaperboard and developer of new packaging concepts.Our product range is second to none. At one end of theproduct spectrum are the household product packag-ing boards, which can be folded into an endless varietyof shapes. At the other are the detergent packagingboards, whose key development principle is user safety.In between the two extremes is a wide range of prod-

ucts, varying in the raw materials, strengths, mechanicalproperties, bleaching degrees and surface nishes used.

All household packaging boards are available with ap-propriate polymer coatings. Material options also includeLumiLabel exible packaging papers as well as corru-gated packaging.

For consultation on the choice of material or other pack-aging issues, please contact us.

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7.7 Food

There is no substitute for bre-based paperboard as thebest material for imaginative, exciting and functional

food packaging. Paperboard is smooth and strong, lightand bright, versatile and cost-efcient. It lends itself per-

fectly to all the shapes, sizes, designs and constructionsthat different products and market situations call for.The material is also ideal to use with metal detectors andother safety measures.

ApplicationsPackaging solutions based on Stora Enso food packagingboards cover a multitude of forms, designes and sizes inall major product segments:

Chilled Foods: Vegetables and salads, meat and sh, processed food, puddings and dressings, etc.

Frozen foods: Ready meals, sh and seafood, icecream, bakery products, etc.

Dry foods: Biscuits, cereals, candy, drink powders,teas, snacks and chips, spices, etc.

Pet foods: Wet/dry cat foods and dog foods, etc.

For primary packaging purposes, vital factors in theselection of the paperboard include: - Organoleptic performance of the baseboard/poly-

mer coating combination- Optical properties (brightness, printability, smooth-

ness, ageing resistance)- Convertibility and runnability (creasability, atness,

no-dusting performance)

- Strength in relation to the size and weight of thecontents (bending stiffness, tear resistance,glueability)

In secondary packaging, cost-effectiveness, sourcereduction capacity, stiffness and, especially in the caseof promotional packs, suitability for digital printing areproperties that usually play a more prominent role.However, every project has its own specic demands. Forconsultation on your specic packaging tasks, please feel

free to contact us.

The essential companion: barrier coatingsIn food packaging, preserving the freshness and palat-ability of even the most delicate foods is an absolutemust. A full range of polymer coatings makes it possibleto create cups, trays and cartons which perform optimal-ly in specic environments for specic products. Ingen-ious combinations of baseboard and coating create a fullspectrum of effective barriers against moisture, oxygen,light, grease or heat.

Read more about the food sector and the many options

for packaging foods at our special site:www.storaenso.com/food.


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7.8 Pharmaceutical

The range of pharmaceutical products is enormous, fromthe most potent prescription drugs to ordinary over-the-counter medicines. Accordingly, the role of packagingranges from ensuring product safety and patient compli-ance to providing a versatile tool for communication andbrand building.

ApplicationsStora Ensos pharmaceutical boards are used in cartons

for all forms of primary packaging aluminium and com-posite blisters, glass and plastic bottles, rigid and collaps-ible tubes, and pouches. In general, cartons for prescrip-tion medicines (antibiotics, cardiacs, potent painkillers,etc.) use fewer colours and more subdued designs, whileOTC (over the counter) products (vitamins and micronu-trients, painkillers, cold medicines and skin creams etc.)invest in attention value, attractive designs and elaborate

nishing.

Sheet offset with water-based varnish is the dominantprinting method.

Basic variable data (lot number, use-by date) is imprintedduring the packing process, using stamping, exo, inkjetor laser techniques.

Narrow Web exo printing with inline converting may

be a cost-efcient alternative for small order lots and isalready applied by several converting companies.

Digitally printed cartons are beginning to gain ground asa viable marketing and testing option.

The choice of paperboard material must be made indi-vidually in each case. Typical variables include:

optical properties (brightness, printability,ageing resistance)

strength (bending stiffness, tear resistance,glueability)

runnabilility in packaging lines (creasability, atness, no-dusting performance, laser codability) quality and hygiene considerations

(material consistency, purity, cleanliness andhomogeneity, odour and taint neutrality)

technical suitability to case-specic technologies(digital printing, etc.).

The applicable grammage is determined by such factors

as box dimensions (bigger sizes need stiffer paperboardin order to perform well in the packing process) and theweight of the contents (improved compression resist-ance is needed for cartons containing heavy products,such as liquids in glass bottles).

Visit our website, www.storaenso.com/pharma to learnmore about the pharmaceutical packaging markets,innovative packaging concepts and the choice of paper-board for individual applications.


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7.9 Food Service

Convenience for Food ServiceStora Enso offers a full range of advanced materials andintegrated solutions for the food service market that ca-

ter to the many different needs of todays active consum-ers, whether it is eat-on-the-go or oven-to-table meal.

Food Service products derive their strength from aunique material that combines specially-developed base-boards and proprietary polymer coatings to create thebest quality in terms of purity, functionality, printabilityand convertibility.

For more information, visit our dedicated site atwww.storaenso.com/cupforma.

7.10 Liquid

Fluid Solutions, Full Protection

The overriding requirement for liquid packaging is tokeep the contents fresh and hygienic, unchanged and

untainted for the entire life of the product. The cartonmust also be attractive, build brand image and boostsales. In addition it must comply with todays best envi-ronmental practices.

Read more about liquid packaging at our special sitewww.storaenso.com/liquid.


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Stora Enso

Service facilities

Consumer Boards Production and

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Service facilities


8. Stora Enso Production and Service facilities

Stora Enso Consumer Boards products are manufacturedin Finland, Germany, Spain and Sweden. The total an-nual capacity of the six modern and well-managed millsis close to 2.6 million tonnes of SBS, FBB, CTMP, SUB

and WLC grades. Extrusion coating plants in Finland andSweden complement the production of baseboards withcomprehensive facilities for moisture and oxygen barriercoatings.

8.1 Paperboard Mills

Baienfurt Mill, Germany

Baienfurt Mill produces packaging boards for a variety ofgeneral packaging applications serving customers in pharma-ceutical, cosmetics, confectionery, cigarette and other majorindustries. In addition, the Baienfurt offering includes a selec-tion of graphical boards.

Annual capacity: 205 000 tons of FBB *Machines: BM 3, machine width 476 cm

Barcelona Mill, Spain

Barcelona Mill produces WLC boards based on recycled bres.The products of the mill serve a great variety of markets from

food, confectionery, detergent and pharma packaging to bookcovers and labelling applications.

Annual capacity: 170 000 tons of WLC coated on both sides *Machines: BM 1, machine width 400 cm

Fors Mill, Sweden

Fors Mill produces fully coated folding boxboards for vari-ous market segments including chocolate, confectionery andcigarette packaging.

Annual capacity: 380 000 tons of FBB and CTMP boards *Machines: BM 2, machine width 372 cm BM 3, machine width 543 cm

49 Stora Enso Consumer Boards Production and Service facilities *) in 2006


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Imatra Mills, Finland

Paperboard production at Imatra Mills comprises liquid pack-aging boards for all packaging systems, cupstock and other

food service boards, packaging boards for the cosmetics, food,confectionery and cigarette industries as well as a selection ofgraphical boards.

Annual capacity: 930 000 tons of SBS, LPB and CTMP boards * 280 000 tons of polymer coated boards *Machines: BM 1, machine width 440 cm BM 2, machine width 560 cm BM 4, machine width 630 cm BM 5, machine width 490 cmCoating machines: PE 2, machine width 230 cm PE 3, machine width 230 cm PE 5, machine width 280 cm

Ingerois Mill, Finland

Ingerois Paperboard Mill offers high-bulk folding boxboards for food, health care, pharmaceutical, liquor and householdindustries.

Annual capacity: 205 000 tons of FBB *Machines: BM 4, machine width 458 cm

*) in 2006 Stora Enso Consumer Boards Production and Service facilities 50

Stora Enso

Service facilities


Skoghall Mill, Sweden

Skoghall Mill is a large-scale producer of liquid packagingboards and the multilayer kraft back CKB concept.

Annual capacity: 745 000 tons of LPB, FBB, WTL andCKB boards *

Machines: KM 7, machine width 540 cm KM 8, machine width 810 cm


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8.2 Extrusion Coating Plants

Forshaga Mill, Sweden

Forshaga Mill produces a range of barrier polymer coatingsincluding foil and lm application on base boards. Typicalend uses include liquid cartons, food packaging, lunch boxes,noodle cups and other carton packaging.

Annual capacity: 140 000 tons of multilayer polymer coatedpackaging boards *

Coating machines: BL 922, machine width 200 cm

BL 923, machine width 200 cm

Karhula Mill, Finland

Karhula Mill is specialised in co-extrusion technology combin-ing different polymers to produce polymer coated boards forliquid and food packaging applications.

Annual capacity: 45 000 tons of multilayer polymer coated

packaging boards *Coating machine: PE 4, machine width 201 cm

51 Stora Enso Consumer Boards Production and Service facilities *) in 2006

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8.3 Partner Services

Location of Stora EnsoServiceCentres

Stora Enso Consumer Boards partner services focus onpromoting innovativeness and enhancing the efciencyand protability of bre-based packaging, thus addingpermanent value to our cooperation with the packagingcommunity.

ServiceCentres for reliability and maximum efciencyThe mission of Stora Enso ServiceCentres is to meetcustomers individual material needs with maximum ef-

ciency, exibility and reliability. Major European marketsare supplied with prompt deliveries of premium boardsand grades coming from various Stora Enso mills. TheServiceCentres are located in the middle of main marketareas and equipped with high-performance sheetingmachinery.

Based on a massive sheeting capacity of 80 tonnes perday, ServiceCentre Baienfurt in Germany offers theconcept of 2-5 servicing. This means ex-mill deliveries ofboards from Baienfurt and other European mills within

two working days from standard sheet stocks and within ve working days from reel stocks.

ServiceCentre Cartiberia in Spain serves customersin the general packaging and graphical industries withboards from the Barcelona, Ingerois, Skoghall and Imatramills. The ServiceCentre has a standard delivery time ofthree to ve days ex-factory.

Other ServiceCentres are in operation in Germany, Swe-den and the UK.

InnoCentreInnoCentre presents a new interface to the future of

bre-based packaging. On the strength of major invest-ments made in people, machinery and equipment,InnoCentre functions as a vehicle for vertical innovation,proactively testing new technology and devising innova-tive packaging concepts. The results of the developmentwork can take many forms, including improved logisticssolutions and novel packaging business models. Theservices of InnoCentre are available to all our partners inthe packaging value chain.

PartnerWebPartnerWeb is Stora Ensos dedicated online real-timesoftware system for managing the supply chain. The so-lution employs an ordinary Internet interface to access acustomer-specic application that lets the user track andmanage the entire order-to-delivery process. PartnerWebis used daily by an increasing number of our key part-ners for improved operational efciency and drastically

reduced routine work. PartnerWeb also supports directsystem integration possibilities utilizing PapiNet XMLmessaging.

For more information visit our dedicated site atwww.storaenso.com/partnerservices.

OSKARSHAMN

LUMIPAPER

CARTIBERIA

LBECK

BAIENFURT

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TestingMethods

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TestingMethods

9. Testing Methods

This chapter describes the testing methodsused for different types of paperboards. These

measurements are made in order to guaran- tee the consistent, high quality of our

products. In the mill environment, testing isconducted using online, autoline and manuallaboratory measurements.

The most important routine quality con-trol tests of different products are described inthis chapter.

Testing standards and calibration

The tests apply to ISO, SCAN and TAPPI standardmethods. If standards are not available, the mills ownmethods, or methods developed in cooperation withcustomers, are used to predict the properties of theproduct. Testing is performed using modern devices andmost of the tests are made in standard conditions. Thestandard conditions are: 23C temperature and 50%relative humidity according to the standard ISO 187(SCAN-P 2:75).

Testing methods

Online testing

Online testing is used to measure the most importantproperties of the paperboard. The measuring head ofthe process computer measures basis weight, caliperand moisture continuou

Paperboard Guide

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Transcript of Paperboard Guide