Converting and Manufacturing Glossary for Packaging

How to read these packaging converting terms

Each entry starts with the term, then any abbreviation, the German (DE) or Dutch (NL) trade equivalent where one is established, and the UK or US variant if it differs. The definition says what the term means, how the process works or is measured, and why it matters for cost, quality or compliance. Typical values are labelled "typically" because machines, materials and converters vary; actual settings for any job are confirmed at quotation and technical review. Where another page covers a topic in depth, a "See:" line links to it.

This page is one of five sub-glossaries under the packaging glossary. Print processes, colour and artwork terms are in the printing and prepress glossary. Paper, board, film and coating grades are in the packaging materials glossary. Test methods and defect names are in the testing, quality and defects glossary. EPR, claims and trade terms are in the regulation, sustainability and trade glossary.

The table shows which machine families make each product group the site covers, so you can tell which sections apply to a given order.

General converting and production

These terms apply across product types: how reels and webs are handled, how jobs are set up and how efficiency and waste are measured.

Blank (DE Zuschnitt, Nutzen)

A blank is a single flat piece cut to its final outline, with creases or fold lines, ready to be folded, glued or formed into a finished pack. Carton blanks, cup sidewall blanks (fans) and corrugated box blanks are all made by die-cutting printed sheets or webs. Blank size and the number of blanks that fit on a sheet or web width largely determine material yield and therefore unit cost.

See: carton dielines, cutting dies and prototyping

Changeover (SMED; DE Umrüsten, Rüstzeit; NL omsteltijd)

Changeover is the work and time needed to switch a production line from one job to the next: removing the previous plates, dies, reels or formats, fitting the new ones and adjusting the machine. SMED (single-minute exchange of die), a method developed by Shigeo Shingo, aims to cut changeovers to under ten minutes by doing as much preparation as possible while the machine is still running. Changeover time is lost output, so short changeovers make smaller runs and frequent design changes more economical.

See: what determines MOQ

Converter (DE Verarbeiter)

A converter is a company that turns base materials such as paper reels, board sheets, film or corrugated board into finished packaging by printing, cutting, laminating, forming, folding and gluing. Converters usually buy their substrates from paper mills, board makers or film extruders, although some plastic bag and film converters extrude their own film. When a buyer speaks of a packaging manufacturer, they usually mean a converter.

See: how to choose a packaging manufacturer

Converting (DE Weiterverarbeitung, Verarbeitung)

Converting is the set of operations that change a base material into a finished packaging item after it leaves the mill or extruder. Typical converting steps are printing, coating, laminating, slitting, sheeting, die-cutting, folding, gluing, welding and forming. The term separates the converter's work from material production upstream and from filling and packing downstream at the brand owner.

See: how custom printed packaging is made

Core (reel core; DE Hülse)

A core is the tube, usually spiral-wound paperboard, on which paper, film or laminate is wound to form a reel. Common inside diameters are 76 mm (3 in) and 152 mm (6 in). Core diameter, wall strength and the maximum reel diameter must match the buyer's unwind equipment, so reel specifications for wrapping or packing machines should state them.

Cut-to-register (print-to-cut register)

Cut-to-register means that cutting, creasing, sealing or forming lands in the correct position relative to the printed design. On web-fed machines, a sensor reads a printed eye mark (register mark) and adjusts the web so each cut falls in the same place on the repeat. Poor cut-to-register shows up as logos running off panels, uneven borders or text cut by a seal, so tolerances for artwork placement near cuts and folds are set with this variation in mind.

See: packaging artwork preparation

Inline vs offline

Inline means that two or more operations, for example printing and bag making, run on one continuous line so material passes from one stage to the next without being rewound or stacked. Offline means each operation runs on a separate machine with reels or pallets of work in progress between them. Inline lines are faster and handle less material but need longer set-up and suit long runs; offline routes are more flexible and allow different print processes, curing periods or inspection between steps.

Jumbo reel (parent reel, mother reel; DE Mutterrolle, Tambour)

A jumbo reel is the full-width, large-diameter reel produced by a paper machine, film extruder, printing press or laminator before it is slit into narrower reels. Jumbo reels can be several metres wide on a paper machine and are cut down by slitting to the widths that converting machines run. Planning finished reel widths to fit within the jumbo width with little edge trim reduces material waste.

Make-ready (US makeready; DE Einrichten, Rüsten)

Make-ready is the set-up of a press or converting machine for a job: mounting plates or tools, bringing colour and registration to target and running waste until saleable product comes off. Its time and material are broadly fixed per job, which is a main reason custom packaging has minimum order quantities. On die cutters, make-ready also includes fitting the counter matrix and adjusting cutting pressure; on bag and cup machines it includes setting format parts and glue or seal settings.

See: what determines MOQ; packaging cost drivers

OEE (overall equipment effectiveness)

OEE is a measure of how productively a machine runs during planned production time, calculated as availability × performance × quality. Availability captures stoppages and changeovers, performance captures running below rated speed, and quality captures waste and rejects; an OEE of about 85 % is often cited as world-class for discrete manufacturing. For a buyer, OEE explains why rated machine speed is a poor guide to real output and why frequent short runs cost more per unit.

Reel (UK; US roll; DE Rolle; NL rol)

A reel is a length of paper, board, film or laminate wound onto a core. Reels are specified by material, width, outside diameter or length, core diameter, winding direction (printed side in or out) and the position of the print relative to the unwinding end. Reel-fed (web-fed) converting is generally faster than sheet-fed converting and is used for bags, cups, film and flexible packaging.

Repeat length (print repeat; cut-off length)

Repeat length is the distance along the web after which the printed design and the cut pattern repeat. On flexo and gravure presses it is set by the circumference of the plate cylinder or sleeve, and on bag, pouch and sheeting machines by the cut-off length of each item. Fitting the item length to an available repeat avoids blank space between items, which wastes material and can affect cost.

Sheeting (DE Querschneiden)

Sheeting is cutting a reel into flat sheets of a set length on a sheeter. Board is sheeted for offset printing and die-cutting, and printed greaseproof paper or MG paper is sheeted into wraps. Accurate sheeting depends on web tension and cut-to-register; for printed wraps the cut has to fall in the same place relative to the design on every sheet.

See: burger wrap sizes

Slitting and rewinding (DE Rollenschneiden)

Slitting and rewinding is cutting a wide reel lengthwise into narrower reels on a slitter-rewinder. Common slitting methods are razor (blade) slitting for films, shear slitting with rotating upper and lower knives for paper, laminates and most packaging materials, and score (crush) slitting for some papers and non-wovens. Clean slit edges and even winding matter because rough edges cause dust and web breaks, and badly wound reels telescope or run unevenly on the next machine.

Splice (flying splice, butt splice; DE Klebestelle)

A splice is the joint where the end of one web is attached to the start of the next, usually with adhesive tape. An automatic splicer makes a flying splice at full speed so the line does not stop when a reel runs out. Splices are a common cause of waste and machine stops downstream, so reels supplied to a buyer's own wrapping or packing machines often have a specified maximum number of splices per reel and a marking method for each splice.

Unwind and rewind

The unwind is the station at the start of a web-fed machine that holds the incoming reel and feeds material into the line under controlled tension; the rewind is the station at the end that winds finished material onto a new core. Many lines have two unwind arms and an automatic splicer so reels can be changed without stopping. Unwind and rewind tension settings affect how tight, flat and stable the finished reel is.

Waste (start-up waste, running waste; DE Makulatur, Ausschuss)

Waste is the material that does not end up as saleable product: make-ready waste while the job is brought to colour and register, running waste from splices, web breaks and rejects, and planned trim from edges and die-cut skeletons. Converters usually allow a waste percentage in their material calculation, which is relatively higher on short runs because start-up waste is broadly fixed per job. Most paper and board waste is baled for recycling, but it is still bought material and a cost.

See: packaging cost drivers

Web (DE Materialbahn, Bahn)

A web is a continuous length of material, such as paper, board, film or laminate, travelling through a machine from an unwind. Web-fed processes include flexo and gravure printing, lamination, slitting, bag making and cup fan die-cutting. The term separates these processes from sheet-fed operations, where each sheet is handled individually.

Web tension

Web tension is the pulling force applied to a moving web, usually measured in newtons or newtons per metre of web width and controlled by dancer rollers, load cells and brakes or drives. Too much tension stretches film and thin paper, which shifts print-to-cut register and changes item length; too little causes wrinkles, wandering and loose reels. Stable tension control is one of the main differences between a well-run line and one that produces variable bags, pouches or wraps.

Paper bag making

Terms used for SOS bags, flat and satchel bags, takeaway bags and handled carrier bags. The production sequence is explained in how paper bags are made.

Block bottom (DE Blockboden)

A block bottom is a rectangular, flat bag bottom formed by folding and gluing the end of a gusseted tube so the bag stands upright when opened. In carrier and food bag usage it is often used interchangeably with SOS or square bottom; in industrial sack making it refers to a pasted rectangular bottom, often with a cover patch, on multiwall sacks. A full glue pattern, a bottom patch or a base card spreads the load and keeps a block bottom from opening under weight.

See: SOS bags explained

Bottom board (base card, bottom insert)

A bottom board is a loose or glued piece of board placed inside the base of a paper bag to keep the bottom flat and spread the load. It is common on hand-finished and premium carrier bags, and on takeaway bags that must carry boxes or containers without sagging. A bottom board adds material and sometimes a manual step, so it should be specified in the quotation rather than added later.

See: paper bag GSM guide

Bottom patch

A bottom patch is an extra piece of paper glued over or inside the folded bottom of a bag to strengthen it and close any gaps in the fold. Patches are used on heavier-duty bags and on bags for greasy or moist food, where an unpatched bottom is a likely failure or leak point. A bottomer with a patch unit applies it inline.

Bottomer (DE Bodenleger)

A bottomer is the machine section, or separate machine, that forms the bottom of a paper bag or sack from a cut length of tube. It opens the tube end, folds it into the bottom shape, applies glue and presses it closed, producing an SOS, block, pinch or flat bottom depending on the machine. On modern reel-fed bag lines the tube former and bottomer run inline as one machine.

See: how paper bags are made

Cut-off (serrated cut, straight cut)

The cut-off is the transverse cut that separates each bag-length of tube from the continuous web, and the shape of its blade gives the bag mouth its edge. A serrated (zigzag) cut-off gives the familiar grocery and SOS bag top, is easy to open and hides small register variations; a straight cut gives a cleaner edge, preferred for printed carrier bags with a top fold. The cut-off length also sets the bag height before any top fold.

See: SOS bags explained

Die-cut handle (paper bags)

A die-cut handle on a paper bag is a hand hole punched through the top of the front and back panels, usually behind a reinforcement card or a folded top. It avoids a separate handle and gives a flat, mono-material bag, but concentrates load at the slot edge, so the slot shape, its distance from the top edge and the reinforcement width decide whether it tears. Bags with die-cut handles usually need extra height to keep usable carrying space.

See: paper bag handle types

Flat bag (flat paper bag; DE Flachbeutel)

A flat bag is a paper bag with no gussets that lies completely flat, made by folding a sheet or tube and gluing the side seam and bottom. Flat bags are used for bakery items, sandwiches, pharmacy and merchandise; a variant with side gussets (DE Seitenfaltenbeutel) holds more volume but still has a narrow folded bottom. Flat and side-gusset bags are typically made on high-speed reel-fed machines from light MG or MF papers.

See: paper food bag sizes; bakery bags guide

Flat handle (flat paper handle, flat tape handle)

A flat handle is a loop of folded paper tape glued to the inside of a bag's top edge, usually with the ends forming their own patches. It is applied inline on reel-fed handle bag machines and is lower in cost than a twisted handle, which is why it is common on takeaway and fast-food bags. Flat handles are less comfortable for heavy loads because the narrow tape edge presses into the hand.

See: paper bag handle types

Hand-finished bag (handmade bag)

A hand-finished bag is a carrier bag whose final steps, typically gluing the bottom, fitting a bottom board, punching holes and threading rope or ribbon handles, are done by hand rather than on an automatic line. The route suits heavier coated or laminated papers, special finishes and small runs, but labour makes the unit price much higher than for machine-made bags. Hand-finished bags are typical in luxury retail rather than in foodservice.

See: paper bag handle types

Handle patch

A handle patch is the paper piece glued to the inside of a bag's top edge that anchors a twisted or flat handle. On automatic lines the handle unit forms the handle and its patches from paper strips and cord and glues them to the web before the bag is formed. The patch area takes space on the inside and shows through as a slightly thicker zone, so artwork near the top of the panel should allow for it.

See: paper bag handle types

Pinch bottom

A pinch bottom is a bag or sack closure in which the stepped end of the tube is folded over and glued flat, without forming a rectangular base. Pinch-bottom bags are common for multiwall sacks and some food and pet food bags because the closure seals well and can be closed with hot-melt after filling. They do not stand open on a counter the way SOS bags do.

Reel-fed bag machine (web-fed bag machine)

A reel-fed bag machine converts a reel of paper, usually printed, into finished bags in one pass: forming a tube, cutting it to length and forming the bottom, often with an inline handle unit for carrier bags. It runs at high speed with low labour and suits large quantities of SOS, flat, satchel and handled bags in kraft and MG papers. Format parts limit each machine to a range of widths, gussets and heights, which is why standard size ranges exist.

See: how paper bags are made

Reinforcement card (top reinforcement)

A reinforcement card is a strip of board or heavy paper glued inside the top of a bag to stiffen the opening and spread handle loads. It is standard on bags with rope handles threaded through punched holes and on die-cut handle bags, where the hole would otherwise tear the paper wall. Its width and grammage are part of the bag specification and should be confirmed for heavy loads.

See: paper bag handle types

Rope handle

A rope handle is a cord of paper, cotton, polypropylene or other fibre threaded through punched holes in the top of a bag and knotted or fixed inside behind a reinforcement card. Rope handles are usually fitted by hand on hand-finished bags. A polypropylene rope on a paper bag adds a different material, which can affect recyclability assessments, so a paper rope is the lower-risk choice for a mono-material paper bag.

See: paper bag handle types; paper bag regulations by market

Satchel bag (UK)

In the UK, a satchel bag usually means a paper bag with a flat, rectangular base and no handles, similar to an SOS bag, used by bakeries, delis and takeaways. The term is used loosely, so a satchel quotation should state the construction: gusset depth, bottom type and whether the bag stands on its own. In the US the same bag is usually just called an SOS or square-bottom bag.

See: SOS bags explained

Sheet-fed bag machine

A sheet-fed bag machine forms bags from individual printed sheets instead of a reel, folding them into a tube, gluing the side seam and forming the bottom, often with semi-automatic or manual steps for handles. It handles heavier papers, coated and laminated sheets and finishes that are printed or applied sheet-fed, typically from around 120 gsm to well over 200 gsm. The route costs more per bag than reel-fed production but allows offset print, film lamination, foil and premium handles.

See: how paper bags are made

Side gusset (DE Seitenfalte)

A side gusset is the inward fold along each side of a bag that expands to give depth when the bag is opened. On paper bags the gusset is folded by the tube former, and its depth together with width and height gives the bag size, stated as width × gusset × height in millimetres. Gusset depth sets the base area and therefore how wide items such as food boxes or containers fit flat.

See: paper carrier bag sizes; takeaway bag sizes

SOS bottom (self-opening square bottom)

An SOS bottom is the flat, rectangular folded-and-glued bottom of a self-opening sack, formed by a bottomer from a side-gusseted tube. When the bag is flicked open, the bottom unfolds into a flat base and the side gussets let it stand freely, which suits counter filling. The glue pattern and paper strength at the bottom folds are the main factors in how much weight an SOS bag carries.

See: SOS bags explained

Thumb notch (thumb cut)

A thumb notch is a small semicircular or V-shaped cut in the mouth of a bag, usually on the front panel, that makes it easier to grip one wall and open the bag. It is common on SOS and flat bags and is made inline by the cut-off knife or a separate punch. Artwork near the top edge should leave the notch area clear of important text.

Top fold (turnover; top hem)

A top fold, or turnover, is the band of paper at the bag mouth folded inward and glued to strengthen the opening and give a clean, finished edge. It is standard on handled carrier bags and premium bags, where it also covers the handle patches or reinforcement card. A top fold changes the printed height of the panel, so dielines show whether bag height is stated before or after the fold.

See: paper carrier bag sizes

Tube former (tuber; DE Schlauchmaschine)

A tube former is the machine section that folds a flat web of paper into a continuous tube, glues the longitudinal (side) seam and, if required, folds the side gussets. The tube is then cut to bag length by the cut-off and passed to the bottomer. Seam glue width, paper grain direction and the position of the print relative to the seam all have to be set on the tube former, which is why bag artwork follows the converter's dieline for that size.

See: how paper bags are made

Twisted handle (twisted paper handle)

A twisted handle is a loop of twisted paper cord, with its ends glued between two paper patches, attached to the inside of a carrier bag's top. On automatic lines a handle unit twists paper strips into cord, forms the loop and patches and applies them to the web before tube forming. Twisted handles give a rounder, more comfortable grip for heavier loads than flat handles, at a higher unit cost.

See: paper bag handle types; custom printed paper carrier bags

Paper cups and food containers

Terms for single wall, double wall and ripple cups, soup and food containers and their lids. The full sequence is in how paper cups and food containers are made.

Bottom knurling

Bottom knurling is the step on a cup or container forming machine that seals the bottom. The sidewall's lower edge is folded inward over the skirt of the bottom disc, and a heated knurling wheel presses the layers together under pressure, fusing the coating. Insufficient heat or pressure here is a common cause of slow leaks at the base, which is why leak tests on samples focus on the bottom seam.

See: how paper cups and food containers are made

Bottom stock (bottom reel)

Bottom stock is the coated paperboard from which cup and container bottoms are punched, usually fed to the forming machine as a narrow reel. It is often a lighter board than the sidewall and is coated on the side that faces the contents. The bottom's barrier must match the sidewall's, so a PE-free or dispersion-coated cup needs a compatible bottom stock as well.

See: paper cup linings

Cup forming machine (cup machine)

A cup forming machine turns printed, die-cut sidewall blanks and a reel of bottom stock into finished cups. It wraps each blank around a tapered mandrel and seals the side seam, punches and inserts the bottom disc, folds and knurls the bottom, and curls the rim. Container forming machines for soup cups and food bowls work the same way with larger diameters and heavier board; each machine runs a limited range of sizes, with format parts changed between them.

See: how paper cups and food containers are made; custom printed paper cups

Cupstock (cupboard; DE Becherkarton)

Cupstock is paperboard made specifically for forming cups and round containers, typically 170-350 gsm, made from virgin fibre and internally sized so liquid does not wick into the cut edges. It is coated on the inside, and on both sides for cold cups, with PE or an aqueous dispersion barrier. In converting, cupstock is printed on reels or sheets and then die-cut into sidewall blanks.

See: paper cup linings; packaging materials glossary

Die-cutting of cup blanks

Die-cutting of cup blanks is the operation that cuts printed cupstock into curved sidewall blanks, also called cup fans, usually on a platen or rotary die cutter. The blanks are nested on the sheet or web to reduce trim, and the die must match the forming machine's mandrel and the cup size exactly. Print-to-cut accuracy at this stage decides whether the design meets cleanly at the side seam.

See: paper cup printing

Double wall and ripple wrapping

Double wall and ripple wrapping is the operation that adds an outer insulating layer to a formed single wall cup, either inline or on a separate wrapping machine. For a double wall cup a smooth printed board wrap is glued around the inner cup with a thin air gap; for a ripple cup the wrap is an embossed, fluted paper that touches the inner cup only at the ridges. The extra layer and step raise unit cost, and the wrap carries the print, so the inner cup is often unprinted.

See: single vs double vs ripple wall cups

Hot air sealing

Hot air sealing is a method of sealing a cup side seam or bottom by blowing heated air onto the coated surfaces to melt the coating, then pressing them together. It is widely used on cup and container forming machines for PE-coated board. Air temperature, dwell time and pressure must suit the coating, so changing from PE to a dispersion or PLA coating usually needs new seal settings and trials.

See: paper cup linings

Lid fit

Lid fit is how securely a lid snaps onto the rim curl of a cup or container and how well it seals against leaks. It depends on the rim's outside diameter, the curl's shape and consistency, and the lid's design and material, which is why lids and cups are matched by size and often by supplier. Poor lid fit causes leaks and pop-offs in delivery, so lids should be tested on production samples of the actual cup.

See: lids for paper food containers

Mandrel

A mandrel is the tapered forming tool on a cup or container machine around which the sidewall blank is wrapped and sealed. Its dimensions set the cup's top and bottom diameters and its taper, so each cup size needs its own mandrel set. Mandrel tooling is one reason cup sizes come in fixed ranges and a new size needs tooling investment.

Nesting (stack height; denesting)

Nesting is the stacking of cups or containers inside one another for packing and transport, and denesting is separating them again by hand or by machine. Stack height per piece depends on the cup's taper and a stacking shoulder or ring that stops cups jamming together. Good nesting reduces shipping volume, while cups that wedge tightly slow down service and can damage rims.

See: paper cup sizes

PE extrusion coating (PE coating)

PE extrusion coating is the process of applying molten low-density polyethylene from a flat die as a thin continuous film onto paperboard moving through a chill roll nip. For cupstock, PE coat weights are typically in the region of 12-20 g/m² per coated side, giving water resistance and heat sealability. PE-coated cups and containers are treated as containing plastic under EU and UK single-use plastics rules.

See: barrier coatings for paper packaging; paper cup linings

Press-formed tray (pressed paperboard container)

A press-formed tray is a paperboard tray or plate shaped in a heated mould from a single flat blank, with pleats forming at the corners or around the wall. Unlike formed cups, it has no side seam, which helps with grease and liquid hold-out at the corners. The board is usually coated and the pleats are pressed tight under heat and pressure.

Rim curl (rim roll)

The rim curl is the rolled top edge of a cup or container, formed by turning the sidewall outward and down into a tight bead. It gives the opening its rigidity, a comfortable drinking edge and the seat for the lid. Variation in curl diameter is a common cause of poor lid fit.

See: lids for paper food containers

Side seam (cup side seam overlap)

The side seam is the vertical overlap where the two ends of a sidewall blank are sealed together to form the cup wall. It is a few millimetres wide and is sealed by hot air or ultrasonics. Artwork must allow for the overlap, which hides part of one end of the design, and for the exposed edge on the inside, which is why cupstock is internally sized against edge wicking.

See: paper cup printing

Sidewall blank (cup fan)

A sidewall blank, or cup fan, is the curved, flat piece of printed cupstock that becomes the cup wall. Its arc shape comes from unrolling a cone, so a line must follow the arc of the fan to appear as a horizontal circle on the finished cup, and a straight line on the fan ends up curved. Artwork for cups is therefore made on a distorted fan template supplied by the converter for that exact size.

See: paper cup printing

Ultrasonic sealing

Ultrasonic sealing joins the side seam of a cup or container with high-frequency mechanical vibration, commonly around 20 kHz, that generates heat at the interface between the coated surfaces. Heat is created only where it is needed, so it seals quickly with little energy and is suited to some coatings that are hard to seal with hot air. Seal quality depends on horn pressure, amplitude and the coating, so it is set and checked per material.

Sheet-fed board converting

Terms for die-cutting, stripping and folder-gluing folding cartons, burger boxes and takeaway boxes. The route is described in how folding cartons and takeaway boxes are made.

Blanking (DE Nutzentrennen)

Blanking is separating die-cut blanks from each other and from the remaining sheet frame at the delivery end of a platen die cutter, so they come out as stacks of individual blanks ready for gluing. Without a blanking station, blanks are knocked out of the sheet by hand or on a separate breaker. Blanking needs the nicks between blanks to break cleanly, which affects nick placement in the die design.

Cold foil (cold foil transfer; DE Kaltfolie)

Cold foil applies a metallised layer by printing a UV-curable adhesive in the image area and then laminating and peeling a foil carrier, so the metal transfers only where the adhesive is. It runs inline on suitably equipped offset or flexo presses, needs no heated die and can be overprinted with process colours to create coloured metallic effects, but it usually gives a flatter, slightly less brilliant finish than hot foil.

See: carton finishes

Counter (make-ready matrix, creasing matrix; DE Rillmatrize)

A counter is the plate or set of channel strips mounted opposite the creasing rules on a die cutter, giving each crease a channel into which the board is pressed. Channel width and depth are chosen for the board's caliper and the rule thickness; a common rule of thumb puts channel width at about 1.5 times the board caliper plus the rule width. A wrong counter produces cracked creases, weak folds or cartons that spring open.

See: carton dielines, cutting dies and prototyping

Crash-lock bottom (auto-bottom, auto-lock bottom; DE Automatikboden)

A crash-lock bottom is a carton base that is pre-glued on the folder-gluer so it springs into a locked, flat bottom when the flattened carton is opened. Gluing the bottom flaps needs a folder-gluer with crash-lock (back fold) sections, so it costs more to produce than a tuck end but saves time when packing. It carries heavier contents than a tuck bottom.

See: folding carton styles

Creasing rule (DE Rilllinie)

A creasing rule is a blunt-edged steel rule in a cutting die that presses a fold line into board without cutting it. Creasing rules are lower than cutting rules by roughly the board thickness and are paired with channels in the counter. The crease's width, depth and position decide how cleanly and accurately a carton folds, and on recycled or coated boards whether the surface cracks.

See: carton dielines, cutting dies and prototyping

Cutting die (DE Stanzform; NL stansmes)

A cutting die is the tool, typically steel rules set in a board base, that cuts and creases printed sheets into blanks in one stroke; die-cutting is that operation. A die is made per size and style and is a one-off tooling cost that can be reused on repeat orders. Flatbed dies for platen die cutters are flat; dies for rotary die cutters are curved or solid engraved cylinders.

See: carton dielines, cutting dies and prototyping; packaging cost drivers

Embossing and debossing (DE Prägung, Blindprägung; NL preeg)

Embossing raises an area of board or paper and debossing presses it below the surface, using a matched male and female die pair under pressure, often with heat. Depth, sharpness and whether the effect is registered to print depend on board caliper, fibre type and die quality; heavy embossing can crack coated surfaces or weaken thin board.

See: carton finishes

Folder-gluer (DE Faltschachtelklebemaschine)

A folder-gluer is the machine that folds die-cut carton blanks along their creases, applies adhesive and presses the glued joints so the carton leaves flat and ready to erect. A straight-line folder-gluer makes simple side-seam cartons; machines with crash-lock sections make auto-bottom cartons; 4-corner and 6-corner configurations make trays and boxes glued at the corners, such as some burger and takeaway boxes. Folder-gluer speed and set-up time are a major part of carton cost for complex styles.

See: folding carton styles; custom printed folding cartons

Folder-gluer adhesives (cold glue and hot melt)

Folder-gluers use either cold glue, typically a water-based PVAc or similar emulsion applied by glue wheel or nozzle, or hot melt applied molten from a heated tank. Cold glue is the norm for carton side seams and gives strong fibre-tearing bonds once dry; hot melt bonds instantly and suits coated or difficult surfaces and high-speed corner gluing. Adhesives for food packaging are part of the food-contact assessment, so their type is recorded in the specification.

See: food-contact packaging compliance

Glue flap (DE Klebelasche)

A glue flap is the narrow panel along one edge of a carton or box blank that is glued to the opposite panel to close the side seam. On a dieline it is usually 12-20 mm wide for cartons, tapered at the ends so it does not foul the fold. The glue flap is normally left unprinted or varnish-free where adhesive is applied, because coatings can stop the glue bonding.

See: packaging artwork preparation

Gripper margin (gripper edge; DE Greiferrand)

The gripper margin is the unprinted strip along the leading edge of a sheet by which the grippers of a sheet-fed press or die cutter hold and transport it, typically around 10 mm. No blank or print can be placed in it, so it is included when the converter calculates the sheet size and the number of blanks per sheet.

Hot foil stamping (hot foil; DE Heißfolienprägung; NL foliedruk)

Hot foil stamping transfers a metallised or pigmented layer from a carrier film onto the substrate using a heated metal die, pressure and dwell time, as a separate pass or on a combined foiling and die-cutting machine. Die temperature, pressure and speed must suit the substrate and foil grade; it gives bright, sharp metallic areas but adds a die cost and a production step, and large metallised areas can affect paper recyclability assessments.

See: carton finishes

Manufacturer's joint

The manufacturer's joint is the seam where the two ends of a carton or corrugated box blank are joined by the converter, normally by gluing on a folder-gluer and, for some corrugated boxes, by stitching or taping. It is formed by the glue flap and the opposite panel and is usually placed at a rear corner. Its strength matters for packing lines and for boxes that are erected and loaded quickly by hand.

Nicks (ties; DE Haltepunkte)

Nicks are small gaps ground into a cutting rule that leave tiny uncut bridges, typically a fraction of a millimetre wide, holding each blank in the sheet until stripping and blanking. Without them, blanks would fall out and jam the die cutter. Nicks leave small visible marks on the cut edge, so their position is agreed away from visible edges on premium cartons.

Number up (ups; step-and-repeat layout)

Number up is how many blanks are placed on one printed sheet or across one web, for example "8-up". The converter chooses it from sheet size, press and die cutter format, blank shape and how well blanks nest together. More ups per sheet reduce the cost per carton but increase die cost, so the layout is part of the quotation rather than something buyers usually specify.

See: packaging cost drivers

Perforating rule and cut-crease rule

A perforating rule is a cutting rule with regular gaps that produces a line of short cuts for tear-off features, while a cut-crease rule alternates cuts and creases so heavy board folds more easily. Both are used in carton dies for tear strips, dispensing openings and easy-fold panels. The cut-to-tie ratio controls how easily the line tears, so it is tested on samples before production.

See: carton dielines, cutting dies and prototyping

Platen die cutter (flatbed die cutter; DE Flachbettstanze)

A platen die cutter cuts and creases sheets between a flat steel rule die and a flat counter plate that close in a vertical stroke, much like a press. Automatic platen die cutters feed sheets one by one and usually strip waste and separate blanks inline. It is the standard machine for folding cartons and for precise corrugated work such as mailer and pizza boxes, giving higher accuracy than rotary die cutting at lower speed.

See: carton dielines, cutting dies and prototyping

Pre-break (prefolding)

Pre-break is a folder-gluer step that folds selected creases, usually the ones that will become the carton's edges, through 180 degrees and back before gluing. It lowers the force needed to open the flat carton and makes erecting easier on automatic packing lines. Cartons for high-speed cartoning machines often specify pre-breaking of particular creases.

Rotary die cutter (DE Rotationsstanze)

A rotary die cutter cuts and creases material between a rotating die cylinder and an anvil or counter cylinder, so the material passes continuously instead of stopping for each stroke. It is much faster than a platen and is used inline on web presses for cup fans, labels and some cartons, and on corrugated lines. Rotary dies cost more to make and register is usually less precise than on a platen.

Steel rule die (DE Bandstahlschnitt)

A steel rule die is a cutting die made by bending cutting and creasing rules and setting them into slots laser-cut in a die board, usually plywood. Ejection rubber glued alongside the rules pushes the material off the cutting edges after each stroke. Standard rules are measured in points (2 pt is about 0.7 mm thick) and are commonly 23.8 mm high; dies can be re-ruled when the cutting edges wear.

See: carton dielines, cutting dies and prototyping

Stripping (DE Ausbrechen)

Stripping is the removal of waste pieces, such as window holes, cut-outs and trim between blanks, from a die-cut sheet. Automatic platen die cutters do it in a stripping station with upper and lower stripping tools made to match each die; otherwise it is done by hand. Stripping tools are part of the tooling cost for complex shapes and windows.

Window patching (DE Fenstereinkleben)

Window patching is gluing a clear film patch over a die-cut window opening on a carton or bag blank, on a window patching machine or a patching unit. The film is typically PET, OPP or a cellulose or compostable film, cut from a reel and glued around the window edge. The film adds a second material that may need separating for recycling, so window size and film type are part of the sustainability and food-contact specification.

See: window paper bags; folding carton styles

Corrugated board and box making

Terms used on the corrugator and in converting corrugated board into pizza boxes, mailer boxes and shipping cases. The sequence is explained in how corrugated packaging is made.

Casemaker

A casemaker is a machine that prints, slots, scores and folds and glues corrugated sheets into regular slotted cases. The term covers both older printer-slotter-folder lines and modern flexo folder-gluers, and it refers to shipping-box production rather than die-cut styles. Casemaker printing is typically one to a few flexo colours on the finished board.

Corrugator (DE Wellpappenanlage)

A corrugator is the line that makes corrugated board from reels of liner and medium: it forms the flutes, glues the layers together with starch, dries and cures the board, then scores, slits and cuts it into sheets. The front of the line, where the board is formed and glued, is called the wet end; the back, where it is slit and cut, is called the dry end. Corrugator settings determine board flatness, bond strength and caliper, which then affect printing and box strength.

See: how corrugated packaging is made

Crush (board crush; caliper loss)

Crush is the loss of corrugated board thickness caused by pressure on the flutes, for example in print or feed nips, during die-cutting or in poor handling. Crushed flutes reduce edge crush and box compression strength even when they are not visible. Converters limit crush by setting nip gaps to the board caliper, which is one reason print and die-cut quality on corrugated involves trade-offs.

See: corrugated board grades for mailer boxes

Double backer

The double backer is the corrugator section where the second liner is glued to the single-face web, closing the flutes to make single wall board, or where several single-face webs are combined into double wall board. The board then travels between heated plates and belts that gelatinise the starch and dry the bond. Uneven heat or pressure here is a common source of warp and weak bonding.

Flexo folder-gluer (FFG)

A flexo folder-gluer is a corrugated converting machine that prints by flexography, slots and scores, optionally rotary die-cuts, folds and glues boxes in one pass. It is the main machine for printed regular slotted cases and simple boxes at high speed. Print on an FFG is applied directly to the corrugated board (post-print), so fine detail is limited compared with litho-lamination.

See: pizza box printing

Flute (flute profile)

A flute is the wave formed in the corrugating medium, and the flute letter describes its height and pitch. Typical single-wall thicknesses are about 0.8-1.0 mm for F-flute, 1.1-1.8 mm for E, 2.5-3.2 mm for B and 3.5-4.5 mm for C, although exact caliper depends on the corrugator and the papers used. Flutes are formed between heated corrugating rolls on the single facer, and each flute profile needs its own roll set.

See: corrugated board grades for mailer boxes; E-flute vs B-flute pizza boxes

Glue lines

Glue lines are the narrow lines of starch adhesive applied to the flute tips that bond the medium to the liners in corrugated board. Their width, continuity and bond strength depend on starch application, heat and speed on the corrugator. Too much starch or a thin liner can show through as visible lines on the printed surface, and weak or missing glue lines lead to delamination.

Liner (linerboard; DE Deckenpapier, Decke)

A liner is a flat paper layer glued to the flutes on the outside or inside of corrugated board. Liners are typically kraftliner (mainly virgin fibre) or testliner (mainly recycled fibre), often with a white or coated top layer for printing. The liners carry print and most of the burst strength; for pizza boxes, liner grammage is commonly in the range of about 120-200 g/m² per liner.

See: packaging materials glossary; corrugated board grades for mailer boxes

Litho-lamination (litho-lam)

Litho-lamination is printing a paper sheet by offset lithography and then laminating it onto corrugated board, combining full-colour print quality with corrugated strength. The printed top sheet is glued to single-face board or to finished board on a sheet laminator, then die-cut. It is used for premium pizza boxes, mailers and display packaging, and avoids most of the washboarding seen with direct print on coarse flutes.

See: pizza box printing

Medium (fluting, corrugating medium; DE Wellenstoff)

The medium is the paper that is corrugated into flutes between the liners of corrugated board. It is typically a recycled or semi-chemical fluting paper; for pizza boxes it is usually around 100-150 g/m². The medium gives the board its thickness and much of its compression resistance, so a weak medium shows up as low crush and stacking strength.

See: packaging materials glossary

Post-print (corrugated)

Post-print means printing directly onto finished corrugated board, usually by flexo in one to three colours, on a flexo folder-gluer or a separate printer. It suits short and medium runs and needs no special board, but pressure on the flutes limits fine detail and can cause washboarding and crush. Most standard printed pizza boxes are post-printed.

See: pizza box printing

Pre-print (corrugated)

Pre-print means printing the liner on reels, usually by high-quality flexo or gravure, before it is corrugated. The printed reel is then run as the outer liner on the corrugator, giving finer print than post-print without the separate step of litho-lamination. Because the liner is printed before the board is made, pre-print suits very large volumes with stable designs.

See: pizza box printing

Rotary die cutting (corrugated)

Rotary die cutting of corrugated board passes sheets between a cylinder carrying a curved steel rule die and a polyurethane-covered anvil cylinder. It is fast and suits high volumes of simpler die-cut boxes, but the curved die and anvil give less precise cuts and creases than a flatbed. The anvil covers wear and are regularly reground or replaced.

Single facer

The single facer is the corrugator section that forms the flutes and glues them to the first liner. The medium is heated and steamed, shaped between meshing corrugating rolls, starch is applied to the flute tips and a pressure roll or belt bonds the liner to them, producing single-face board. Single-face board is also used on its own as a wrap and in litho-lamination.

Slotter-scorer (printer-slotter)

A slotter-scorer is the corrugated converting section that cuts the slots between the flaps of a box blank and presses score lines for folding. Slots let the flaps fold without bulging, and scores are wide creases suited to the thickness of corrugated board. On regular slotted cases this replaces die-cutting, which keeps tooling cost low.

Starch adhesive (DE Stärkekleber)

Starch adhesive is the glue used on corrugators, typically made from corn, wheat or potato starch with caustic soda and borax, which gelatinises with heat to form the bond. Most systems are Stein Hall (carrier) or no-carrier preparations. The starch is cheap and repulpable, so it does not usually affect corrugated board recycling.

Warp (board warp)

Warp is the curling of corrugated board sheets away from flat, caused by an imbalance in moisture or tension between the liners, usually from uneven heating on the corrugator or changes in ambient humidity. Warped sheets feed badly into printers and die cutters, causing misregister, crush and jams. Conditioning board before converting and controlling corrugator heat are the main remedies.

Washboarding

Washboarding is a visible ripple pattern on printed corrugated board where the liner follows the flutes beneath it, most noticeable with coarse flutes and dark or glossy solid print. Finer flutes, heavier liners or litho-lamination reduce it. Because it comes from the board construction as much as from printing, it is best settled at design stage.

See: pizza box printing; corrugated board grades for mailer boxes

Film extrusion, plastic bags and flexible packaging

Terms from film extrusion through printing, lamination and bag or pouch making. The routes are described in how plastic bags are made and how flexible pouches are made.

Bag making machine (film)

A film bag making machine converts a reel of printed tubular or flat film into finished bags by sealing, cutting and, if needed, punching handles. Machine types are named after the seals they make, such as bottom seal, side weld and vest (T-shirt) bag machines, and many include gusseting, wicketing and handle punching units. The machine chosen determines the bag's construction and seal strength, so it follows from the bag style rather than the other way round.

See: plastic bag handle types; custom printed plastic bags

Blow-up ratio (BUR)

The blow-up ratio is the diameter of the inflated film bubble divided by the diameter of the die in blown film extrusion, typically about 2:1 to 4:1. A higher ratio stretches the film more in the cross direction, balancing its strength between machine and cross directions. Blow-up ratio therefore affects how a bag tears and how well it resists puncture, and it changes the layflat width that the line can produce.

See: LDPE vs HDPE vs recycled PE bags

Blown film extrusion (DE Blasfolienextrusion)

Blown film extrusion melts polyethylene or other polymers in an extruder, pushes the melt through a ring-shaped die and inflates it with air into a tall bubble, which is cooled, flattened and wound as tube or slit into flat film. It is the standard process for carrier bag and most packaging PE film. The process sets film thickness, width and orientation, and with it strength, clarity and tear behaviour.

See: how plastic bags are made

Bottom seal bag

A bottom seal bag is a bag made from a layflat or gusseted tube by sealing across the bottom and cutting across the top, so the sides are the tube's folded edges with no side seams. Bottom seals are strong and leak-resistant, which suits refuse sacks, produce bags and many carrier bags. A bottom seal machine typically makes a wider seal than a side weld machine's bead.

Cast film (DE Gießfolie)

Cast film is made by extruding molten polymer through a flat slot die onto a chilled, polished roll, which cools it very quickly. Compared with blown film, cast film has better clarity and gauge uniformity and is produced at higher speeds, but its strength is less balanced between machine and cross direction. Cast polypropylene (CPP) sealant films and stretch film are typical cast products.

See: pouch laminate structures and barrier properties

Co-extrusion (co-ex; DE Koextrusion)

Co-extrusion feeds two or more polymer melts from separate extruders into one die, producing a multilayer film in a single step, typically with three, five, seven or more layers. Each layer can have a different job, such as a print surface, a barrier, a recycled-content core or a sealant. Co-extruded films are generally easier to recycle than laminates of unlike materials when all layers belong to the same polymer family.

See: recyclable mono-material pouches

Corona treatment (DE Coronavorbehandlung)

Corona treatment raises the surface energy of a plastic film by passing it through a high-voltage electrical discharge, which oxidises the surface so inks, coatings and adhesives wet it and bond. It is usually applied inline after extrusion and often again just before printing, because the treatment decays over time. Insufficient or decayed corona treatment is a common cause of poor ink adhesion and ink rub-off on bags.

See: printing on plastic bags

Curing (laminate curing; DE Aushärtung)

Curing is the period after adhesive lamination during which the adhesive completes its chemical reaction and reaches full bond strength. Solventless polyurethane adhesives typically need several days, often two to seven depending on the system, before the laminate is slit or made into pouches. Curing also lets residual reactive components such as isocyanates react away, which is why primary aromatic amine (PAA) checks are linked to cure time for food packaging and why laminated pouches have longer lead times than single-film bags.

See: pouch laminate structures and barrier properties; packaging lead times

Die (extrusion die)

An extrusion die is the shaped metal tool through which molten polymer leaves the extruder: an annular (ring) die for blown film and a flat slot die for cast film and extrusion coating. Die gap and die diameter or width set the starting dimensions of the melt, and die temperature control affects thickness uniformity. Die lines, streaks caused by damage or deposits on the die lips, are a visible film defect.

Dyne level (surface energy)

The dyne level is a film's surface energy, measured in dynes per centimetre or millinewtons per metre (mN/m) with test inks or pens, for example to ISO 8296 or ASTM D2578. Untreated polyethylene is typically around 30-31 mN/m; printing usually needs about 38-42 mN/m and lamination often a similar or higher level. A dyne check before printing is a quick way to confirm that corona treatment is still effective.

See: printing on plastic bags

Extrusion lamination

Extrusion lamination bonds two webs, such as a printed film and a foil or paper, by extruding a thin layer of molten polymer, usually LDPE, between them in a chill roll nip. The polymer layer acts as both adhesive and part of the structure, and no curing period is needed for an adhesive. It is used for paper/PE, foil and film laminates where a thicker bonding layer is acceptable.

See: pouch laminate structures and barrier properties

Frost line (frost line height)

The frost line is the zone above a blown film die where the molten bubble cools and solidifies, visible as a change from clear to hazier film. Its height, set by cooling air and output, affects the film's orientation, clarity and toughness. HDPE film is often run with a high frost line on a narrow stalk to build strength.

Gauge band

A gauge band is a lane of film that is consistently thicker or thinner than the rest of the web, caused by variations around the die or in cooling. If it always falls in the same place, it builds up as a hard ridge or soft band in the wound reel, causing wrinkles and register problems. Blown film lines oscillate or rotate the die or haul-off to spread gauge bands across the reel width.

See: plastic bag thickness: micron, gauge and mil

Hot-bar sealing (constant heat sealing)

Hot-bar sealing presses film layers between jaws that are kept permanently at a set temperature, sealing by heat, pressure and dwell time. It is fast and is the standard method for laminates and pouches, which have heat-resistant outer layers that protect against sticking to the jaws. Seal temperature, pressure and time are set for each structure and checked by seal strength tests.

Hot-knife (hot-knife sealing)

A hot-knife is a heated blade that cuts through two or more film layers and seals the edges in one movement, producing a narrow bead seal. It is used on side weld bag machines and gives bags with neat edges and no seal flange. Bead seal strength depends on blade temperature and film type and is usually lower than a wide bottom seal.

Impulse sealing

Impulse sealing uses a thin heating element that is briefly heated by an electrical pulse while the jaws are closed, then cools under pressure before the jaws open. Because the seal cools while still clamped, it gives strong seals on thick PE and on films that would stick to permanently hot jaws. It is slower than hot-bar sealing and is common on bag machines for heavy-gauge film and on manual or semi-automatic sealers used by food businesses.

Laminating adhesive

A laminating adhesive is the adhesive used to bond films, foil or paper into a laminate, typically a two-component polyurethane system in solvent-based or solventless form, with water-based systems for some applications. Choice of adhesive affects bond strength, heat and chemical resistance, curing time and food-contact suitability. For food pouches, the adhesive supplier's compliance information is part of the documentation for the laminate.

See: food-contact packaging compliance

Lamination (adhesive lamination; DE Kaschierung; NL lamineren)

Lamination in flexible packaging is bonding two or more webs, such as a printed PET film to PE or foil, into one multilayer material on a laminator. The main routes are solvent-based, solventless and extrusion lamination. Reverse printing on the inner side of the outer film, then laminating, protects the print inside the structure. In carton converting, film lamination means bonding a thin film onto printed board for finish.

See: pouch laminate structures and barrier properties; carton finishes

Patch handle welding

Patch handle welding is attaching a separate reinforcing film patch around the handle area of a plastic bag, by heat welding, before the handle hole is punched. The patch doubles the wall at the point of greatest stress, so a patch handle bag carries more than a plain die-cut handle bag of the same film. Loop handles, separate film loops welded onto the bag top, are applied in a similar way.

See: plastic bag handle types

Pouch making machine

A pouch making machine converts printed laminate reels into finished pouches by folding or combining webs, inserting bottom gussets, applying zippers and valves, sealing, notching and cutting. Formats such as three-side seal, stand-up and flat-bottom pouches need different machine configurations. Pouch quality depends on seal integrity, accurate print-to-seal register and consistent dimensions for the buyer's filling line.

See: pouch formats; how flexible pouches are made

Side weld bag (side weld)

A side weld bag is made from folded film by sealing and cutting the two sides with a hot-knife, so the bottom is the fold and the sides carry narrow bead seals. Side weld machines run fast and give neat edges, which suits printed carrier bags, mailing bags and bread bags. Side seals are usually weaker than a bottom seal, so heavy-duty bags often use bottom seal construction instead.

Slitting (film and laminate)

Slitting for film and laminates cuts wide printed or laminated reels into the finished widths needed for pouch making, form-fill-seal machines or the buyer's packing line, usually with razor or shear knives on a slitter-rewinder. Slit width tolerance, winding tension, splice marking and reel direction are specified for automatic machines. For laminates, slitting follows curing.

See: pouch laminate structures and barrier properties

Solvent-based lamination

Solvent-based lamination applies an adhesive dissolved in solvent, typically ethyl acetate, to one web, evaporates the solvent in a drying tunnel and then nips the second web onto it. It handles a wide range of structures, including demanding retort and high-barrier laminates, and builds bond strength quickly. It needs solvent handling and emission control, and residual solvent levels are checked for food packaging.

Solventless lamination

Solventless lamination applies a two-component, 100 %-solids polyurethane adhesive without solvent, in very thin layers, and combines the webs without a drying tunnel. It uses less energy and avoids solvent emissions, and is now the most common route for many food laminates. The adhesive needs a curing period, typically several days, before slitting and pouch making.

See: pouch laminate structures and barrier properties

Three-side seal (3SS; flat pouch)

A three-side seal pouch is a flat pouch sealed on three sides by the converter and left open on the fourth for filling, then sealed by the packer. It is the simplest pouch to make and fill and uses the least material, but it does not stand up. Seal widths, tear notches and any zipper are specified with the pouch dimensions.

See: pouch formats

Valve application

Valve application is fitting a one-way degassing valve to a pouch or bag, by heat sealing or adhesive, usually on the pouch making machine or as an inline unit. The valve lets carbon dioxide from freshly roasted coffee escape while limiting oxygen coming in. Valve position, the hole punched under it and its compatibility with the laminate are specified at artwork stage.

See: pouch features

Wicketing (wicketed bags)

Wicketing is stacking bags on a wire wicket through punched holes in a header lip, so they can be opened and filled one at a time at a counter or on a bagging machine. Wicketed bags are common for bakery and produce bags and some takeaway bags. The bag needs an extra lip and punched holes, so wicketing is specified when the bag is designed.

Zipper application

Zipper application is sealing a reclosable zipper profile into a pouch on the pouch making machine, typically by heat-sealing the zipper flanges to the inner walls just below the top seal. The zipper must be compatible with the pouch's sealant layer, and its position affects the fill height and the space left for the tear notch. Press-to-close zippers are the most common; slider and child-resistant types need specific machine units.

See: pouch features

Tissue, napkin and wrap converting

Terms for printed napkins and sheeted greaseproof or MG wraps. The process is described in how greaseproof wraps and printed napkins are made.

Counted packs (count and stack)

Counted packs are stacks of napkins, wraps or sheets delivered in a fixed count, such as 50, 100 or 500 per pack, formed by a counting and stacking unit at the end of a converting line. The count, pack format and whether packs are banded, film-wrapped or boxed are part of the specification. Accurate counts matter for dispenser filling and for stock control across many outlets.

See: burger wrap sizes

Embossing (tissue embossing; DE Prägung)

Tissue embossing presses a pattern into napkin tissue between an engraved steel roll and a rubber or steel counter roll. It adds bulk, softness and absorbency and can carry a decorative or logo pattern, and it is also used to bond the plies. Embossing is a different operation from the embossing used as a finish on cartons.

See: printed napkins

Fold formats (1/4 fold, 1/8 fold, book fold)

Fold formats are the folding patterns applied to napkins on the folding unit of a converting line. A 1/4 fold folds the sheet twice into a square a quarter of its area and is usual for luncheon napkins; a 1/8 fold adds further folds and is common for dinner napkins; book folds and other variants suit cutlery pockets. The fold decides which part of the sheet faces up, so print position on the flat sheet depends on it.

See: napkin sizes and folds

Interfold

Interfold is a folding pattern in which each napkin or sheet is folded so that it overlaps the next, so pulling one from a dispenser presents the following one. Interfolding is done on a dedicated interfolder, not on standard napkin folding lines. Interfold napkins must match the dispenser's expected fold and size.

See: dispenser napkins

Napkin converting line

A napkin converting line unwinds parent reels of tissue or airlaid, prints them inline, usually by flexo in one to four colours, embosses and bonds the plies, cuts and folds the napkins and counts them into stacks for packing. Each line handles a limited range of sizes and folds. Print register on a napkin line is looser than on board or film, which is why fine detail is avoided on tissue.

See: printed napkins; custom printed napkins

Ply bonding

Ply bonding holds the two or three layers of a multi-ply napkin together, usually by a mechanical edge emboss along the borders or by an all-over emboss pattern, and in some products by glue lamination. Weak ply bonding lets plies separate in use, which looks cheap at the table. A quick check on samples is to rub a damp corner to see whether the plies part.

See: 1-ply, 2-ply, 3-ply and airlaid napkins

Packing, palletising and dispatch

End-of-line terms that decide how finished packaging arrives and how it stores. Pallet standards and shipping terms are covered in sourcing packaging from Türkiye.

Bundling

Bundling is grouping a counted quantity of flat items, such as bags, blanks or folded cartons, into a bundle held by a paper band, film wrap or strapping. Bundle size affects how easily staff handle stock at the counter and how many units go into each shipping carton. Bundled quantities are stated in the packing specification together with the carton count.

Case count (pack count)

The case count is the number of finished items packed in each shipping carton, and in specifications it often sits with bundle size, carton dimensions and cartons per pallet. It affects freight efficiency, storage and how stock is issued to outlets. Agreeing case counts across all outlets of a chain simplifies ordering and stock checks.

See: packaging RFQ guide

Conditioning (DE Klimatisieren)

Conditioning is holding paper, board or packaging at a controlled temperature and humidity so its moisture content stabilises before converting, testing or use; the standard test atmosphere for paper and board is 23 °C and 50 % relative humidity under ISO 187. Board moved from a cold container into a warm store can absorb moisture and warp, so pallets are best left wrapped until they reach room temperature. In film converting, the term is also used for storing laminates while they cure.

See: testing, quality and defects glossary

Edge protectors (corner boards)

Edge protectors are L-shaped strips of laminated paperboard placed on the vertical corners of a pallet load, under strapping or stretch film. They spread strapping pressure, protect carton corners from damage and add some vertical stiffness to the load. They are commonly specified for export shipments of printed packaging, where cartons are handled several times.

Pallet pattern (column stacking, interlocked stacking)

A pallet pattern is the arrangement of cartons on each layer of a pallet. In column stacking, cartons sit directly above each other so their corners carry the load and compression strength is preserved; in interlocked stacking, layers are rotated like brickwork for stability but compression strength can drop considerably. Cartons should not overhang the pallet edge, which also weakens stacks.

See: corrugated board grades for mailer boxes

Palletising (US palletizing; DE Palettieren; NL palletiseren)

Palletising is building finished cartons or bundles into a stable load on a pallet, by hand or by robot, to a set pattern, height and weight. The pallet type (for example Euro pallet 1200 × 800 mm, UK 1200 × 1000 mm or US 48 × 40 in), maximum load height and labelling are part of the buyer's delivery specification. Pallet efficiency strongly affects freight cost per unit on export shipments.

See: sourcing packaging from Türkiye

Shrink wrapping

Shrink wrapping encloses a bundle or pack in a heat-shrinkable film, typically polyethylene or polyolefin, that is passed through a heat tunnel so it tightens around the contents. It is used for packs of cups, lids and other items that need dust protection and a tight, stable unit. On pallets, shrink hoods are an alternative to stretch wrapping.

Strapping

Strapping is binding cartons or bundles, or a whole pallet load, with tensioned bands of polypropylene, polyester or, for heavy loads, steel. It holds loads together during handling and is often combined with edge protectors to stop the straps crushing carton corners. Over-tight strapping can damage the top layer of cartons, so tension is set for the packaging.

Stretch wrapping

Stretch wrapping secures a pallet load by winding stretchable LLDPE film around it under tension, by hand or on a turntable or rotary-arm wrapper. Machine wrappers pre-stretch the film, typically by 150-300 %, before it reaches the load, which reduces film use and increases holding force. Wrapping pattern, top sheet and film thickness are chosen for the load and the transport route.

Using these terms in specifications and supplier reviews

Most converting terms reach a buyer in three places: a dieline with notes such as glue flap, side seam overlap or handle patch area; a technical review that names a machine constraint such as maximum gusset, curing time or mandrel size; and a packing specification that covers case count, pallet pattern and wrapping. Reading those remarks correctly before artwork is approved avoids reprints and delays.

A request for quotation that states the format, size and construction (for example SOS bottom, twisted handle, top fold), the material and coating, the print method, finishing and the packing requirements can be compared like for like between suppliers. The packaging RFQ guide gives the full checklist, and the product hubs, from custom printed takeaway bags and custom printed paper food containers to custom printed pizza boxes and custom printed stand-up pouches, show which construction choices matter for each format.

9 Packaging is an Istanbul-based manufacturer and exporter of printed packaging for business customers, with experience supplying fast-food and chain-style foodservice operations. If a converting remark on a dieline, proof or competing quotation is unclear, send it with your enquiry through our contact page and it will be explained at technical review.

Related reading

• Packaging glossary: paper, board, print and compliance terms
• How custom printed packaging is made
• Printing and prepress glossary for packaging
• Packaging materials glossary
• Packaging testing, quality and defects glossary
• Packaging regulation, sustainability and trade glossary