Label and Tag Media

What label and tag media are

Label and tag media are the printable substrate materials from which finished labels and tags are made — the sheet, film, or web that carries the printed image, rather than the printing process or any print defect. In printing and converting terminology, "media" (or "stock") denotes the material fed through a press or printer, and "label and tag media" is the family of stocks engineered specifically for label and tag applications.

A working distinction separates the two:

• Label media are stocks designed to be affixed to another object. The dominant form is pressure-sensitive (self-adhesive) material, a laminate in which a printable facestock is coated with adhesive and carried on a release liner, though non-adhesive label constructions (wet-glue, in-mould, and shrink-sleeve films) also exist.
• Tag media are stiffer, self-supporting stocks that are not adhered but attached mechanically — tied, wired, hooked, stapled, or inserted — as with hang tags, shipping tags, price tickets, and event tickets.

This page describes the media itself: what it is made from, how it is constructed and graded, the formats it is supplied in, and how its properties are measured and named. The mechanics of applying ink or toner to it, and the defects that can arise, are treated on separate process and defect pages that are cross-linked below.

Label media: pressure-sensitive and non-adhesive constructions

The most common label media form is the pressure-sensitive laminate, a multi-layer construction rather than a single sheet. From the printable surface downward it comprises:

• a facestock — the printable top layer, paper or film, which receives the image and, after conversion, becomes the visible label;
• an adhesive layer — for example permanent, removable, or repositionable;
• a release coating; and
• a liner (backing), typically a siliconised paper or film that protects the adhesive and is discarded when the label is applied.

Only the facestock is printed; the adhesive, release coat, and liner are functional layers. Linerless label media omit the release liner by applying a release coating directly over the printed face, which changes how the web is handled and printed.

Non-adhesive label media use other attachment mechanisms. Wet-glue (cut-and-stack) labels are plain sheets or reels glued to the container during application rather than pre-coated. In-mould labels are films placed into a mould so that the label fuses with a plastic container as it is formed. Shrink-sleeve media are printed films that conform to a container's shape when heated. Because a label facestock must both print well and survive on the labelled object, its selection balances print receptivity against end-use demands such as moisture, abrasion, and temperature.

Tag media: stock, grade, and attachment

Tag media are heavier and more rigid than typical label facestock because a tag must support itself and withstand handling without a backing object. They are supplied without an integral adhesive; attachment is mechanical.

In paper grading, tag and ticket applications are associated with tag board and index board — comparatively thick, strong, dimensionally stable grades. Relative to writing or text papers, tag stock is characterised qualitatively by greater thickness (caliper), higher stiffness, and good tear and folding resistance, so that a tag holds up to being punched, strung, and pulled. Many tag stocks are also treated for moisture resistance where outdoor or shipping use is expected.

Common tag media forms include hang tags, shipping and inventory tags, price tickets, and admission tickets. Some tags carry pre-formed features — a reinforced eyelet, a punched hole, or an attached string or wire — that the media and its converting must accommodate. Where a tag also needs to be adhered in some workflows, an adhesive is added separately rather than being intrinsic to the stock, which is the defining contrast with pressure-sensitive label media.

Facestock and stock materials: paper versus synthetic film

The printable material of both labels and tags falls into two broad families — paper and synthetic film — with coatings applied to tune printability.

• Paper stocks are the traditional choice and are graded much like other printing papers, including coated and uncoated variants. Coated papers present a smoother, more receptive surface for high-resolution printing, while uncoated papers absorb more ink and are used where a natural surface or writability is wanted. That distinction is the subject of the coated-versus-uncoated reference cross-linked below.
• Synthetic (film) stocks are polymer materials — among them polypropylene, polyethylene, polyester (PET), and vinyl (PVC) — chosen when durability, moisture resistance, flexibility, or clarity is required beyond what paper provides.

Independent of the base material, label and tag media are frequently top-coated so the surface is compatible with a given printing method. Thermal media are a distinct category defined by their coating. Direct-thermal media carry a heat-sensitive coating that darkens when heated by a thermal printhead, so no ribbon is used. Thermal-transfer-receptive media are formulated to accept ink melted from a thermal transfer ribbon. Other stocks are surface-treated to receive inkjet inks or to fuse toner in laser and LED printing. The coating, not merely the base sheet, therefore often determines which printing process a given medium suits.

Formats, construction, and layout

Label and tag media are supplied in several physical formats, and the format is part of the media specification because it governs how the material feeds and registers in a printer or press.

• Cut sheets follow standardised trimmed sizes; the A- and B-series sizes defined by ISO 216 are a common reference for sheet dimensions, though label sheets are frequently die-cut into multiple labels per sheet.
• Roll (web) media are wound on a core and are described by parameters such as web width, roll (outside) diameter, core diameter, and wind direction (whether the printable face winds in or out). Die-cut roll labels are separated by gaps, and the repeat distance from one label to the next is the pitch; sensing marks or the liner gap allow a printer to register each label.
• Fanfold media are continuous stock folded at perforations rather than wound, used in some high-volume and industrial workflows.

Labels may be die-cut to shape on the liner (with the surrounding waste matrix stripped away) or supplied as continuous stock that the operator cuts to length. Tags are commonly supplied die-cut with holes or perforations already formed. These construction choices interact with the feed and registration behaviour of the printing device and are a frequent source of media-specific handling requirements.

How label and tag media are measured and specified

The properties of label and tag media are described using the same metrology as other paper and film substrates, supplemented by tests specific to adhesives and durability. These measurement standards can be named without reproducing their threshold values.

Substrate (paper and film) properties:

• Grammage — mass per unit area — is defined by ISO 536; comparable basis-weight and grammage tests are also published by TAPPI (for example TAPPI T 410).
• Caliper (thickness) is measured under standardised methods such as TAPPI T 411 and expressed in micrometres or in thousandths of an inch (mils/points). Grammage and caliper together are treated on the paper weight and caliper reference.
• Brightness is defined by ISO 2470 (ISO brightness), with TAPPI methods such as T 452 covering comparable directional-reflectance measurements; brightness and whiteness are distinct optical measures.
• Opacity — the degree to which a stock prevents show-through of what is printed behind it — is defined by ISO 2471 (and by TAPPI T 425).

Adhesive and durability properties (label media):

• Peel adhesion, tack, and shear (holding power) of pressure-sensitive constructions are evaluated using standardised methods published by industry bodies such as FINAT (the FINAT Test Methods, FTM) and by ASTM International.
• Print and label durability for demanding uses is addressed by application standards; for example, BS 5609 specifies durability requirements for pressure-sensitive labels intended to survive marine and chemical-drum exposure.

Because published standards define methods — and in some cases grades — rather than a single universal value, media data sheets report measured results against these methods rather than one figure that applies to every stock.

Role in printing and print quality

The choice of label or tag media is a primary determinant of print quality because the substrate governs how ink or toner is received, held, and displayed. Several media properties act directly on the printed result:

• Surface receptivity and coating decide how well ink adheres and how sharply it prints. A mismatch between medium and process — for instance, running an untopcoated film through a method it was not formulated for — can degrade density and edge definition.
• Ink or toner spread on the surface influences apparent dot size; this ink-spreading behaviour is the subject of the dot-gain reference and is strongly stock-dependent.
• Opacity and caliper affect whether printing on the reverse or on a layer beneath is visible from the front, which the show-through reference treats as a defect.
• Brightness and whiteness of the stock change the contrast and colour appearance of the printed image.
• Durability of the facestock — moisture, abrasion, chemical, and heat resistance — determines whether the printed label or tag survives its service life, which is a main reason synthetic films are selected.

Media must also run through the machine reliably. Stiffness, caliper, and surface friction affect feeding and registration, which is why heavy tag stock and thin liner-mounted labels place different demands on transport hardware; the paper feed rollers reference covers that mechanism. Dimensional response to moisture and heat can produce curl, treated as a defect on the paper curl page. This page describes the media properties themselves; the linked pages describe the processes that act on them and the defects that can result.

Relationship to adjacent concepts

Label and tag media sit at the intersection of several topics that are documented separately.

• Paper-property references — coated-versus-uncoated paper, paper weight and caliper, paper opacity, paper brightness and whiteness, and paper sizes — describe the underlying substrate attributes that also apply to paper-based label and tag stock. This page draws on those attributes but focuses on the label and tag context: adhesive laminates and liners, synthetic films, thermal coatings, and roll and tag formats that general printing paper does not have.
• Consumable references — such as the thermal transfer ribbon — describe materials that pair with a medium (a thermal-transfer ribbon prints onto thermal-transfer-receptive media) and are complementary to, not part of, the media itself.
• Process references — inkjet, laser, and dye-sublimation printing — describe how an image is placed on the medium, while ink references such as pigment-based ink describe what is placed. The media page describes the receiving surface.
• Defect references — show-through, print mottle, and paper curl — describe failure modes that depend partly on media properties but are analysed as outcomes rather than as the material.

Treating the media as its own subject keeps these boundaries clear: the medium is the physical stock, the process is the act of printing, the consumable is the marking material, and the defect is an undesired result.