Glossary

Acrylic Adhesive

A pressure-based adhesive suitable for applying to a range of materials, including glass, metal, or wood. Somewhat less effective on plastic and can be more expensive than rubber-based adhesive. They are extremely versatile as they are resistant to UV light, moisture, solvents, and extreme temperatures.

Adhesive

Adhesives are used to bond different materials together and can be permanent, semi-permanent, or temporary. They are also often grouped into organic or synthetic categories and then into categories by how they form a bond. Pressure-sensitive adhesive is one of the most common types used in the industry.

Anti-fog film

A thin layer of material that prevents water condensation from forming small droplets on the substrate surface.

Application temperature

Application temperature refers to the label and substrate temperature and may not be identical at the time of application. All labels have a minimum recommended temperature, which may affect the adhesive function if the label or substrate drops below that temp during application.

Bleed

The area where printing goes beyond the trim edge to ensure complete ink coverage.

Blockout Labels

Labels made to block out anything appearing on the substrate to which it is applied. The opaqueness may come from the face material, adhesive, an opaque coating, or any combination of the three. Blockout labels are used to hide errors, change graphics, or update existing information.

Caliper

The thickness of a material, most often measured in mils (one-thousandth of an inch) or microns (one-thousandth of a millimeter).

Clinical Trial Label

Labels designed to meet the requirements of the Code of Federal Regulations in the US and the Guideline on Readability in the European Union. They are specially engineered to withstand the extreme temperature of testing storage and matching primary packaging. They can have blinding, randomized computerized data printing, code-break scratch areas, and tamper-evident features as needed.

Co-Extruded film

A film made up of one or more layers of film with different characteristics. One example is “chip film,” or a cereal liner, which combines HDPE for barrier protection and LDPE for sealability.

Coated Paper

Paper that has been coated with a finishing layer to improve its opacity, printability, and durability. Coatings are also applied to achieve aesthetic effects such as brightness, whiteness, surface smoothness, and matte or glossy textures.

Cut and Stack Labels

Labels that are printed on large sheets, then cut and bundled into stacks. The alternate format is to leave them on multiple-up sheets or rolls for application.

Die

A piece of equipment used to cut material to a final desired shape. Factors to consider when making dies include the material being cut, the cutting process best suited to the job, and the lifespan needed for that particular die.

Die-Cut

Any material, including label stock, cut to shape using a die.

Digitally Printed Labels

Labels that start as digital files which are converted into a dot matrix pattern, usually via a Raster Image Processor. The resolution of the final image is specified in pixels/inch (PPI). Since no plates are involved, variable image printing is an option, where each impression can vary slightly from the previous one, if desired.

Facestock

The top layer of material bonded to a layer of adhesive. This top layer may include paper, fabric, films, or foils with or without additional treatments or coatings.

Flexible Packaging

These containers, when filled, will roughly conform to the shape of their contents. Flexible packaging can be lower in cost due to less material consumption and made from sustainable materials, making it an attractive alternative to rigid packaging.

Flexible Packaging Film

Aflexible packaging structure typically consisting of multiple laminated layers, with each layer playing an essential role in your product's performance and presentation.

Flexographic Image Reproduction Specifications & Tolerances (FIRST)

A set of specifications created and maintained by the Flexographic Technical Association. FIRST defines terminology, workflows, design elements, prepress procedures, and pressrun tools aimed at producing consistent flexographic materials throughout the industry.

Flexographic Label

Labels created using a flexographic printing process. This process involves passing label stock through a series of flexible printing relief plates, each coated with a single printed color that works in tandem to produce the final full-color label. Flexographic printing can incorporate laminating, folding, or die-cutting into a single pass operation.

Flexographic printing

A printing process using flexible plates that are inked and then applied to a substrate with pressure to transfer the ink. It works with a variety of inks and can be used on a wide range of substrates from paper to films to plastics.

Flood

Fully cover the paper/film with ink or varnish.

Form-Fill-Seal Machines

This machine uses flexible packaging roll stock to form a premade pouch, fills the bag with the product, and finally seals it.

Four color process

A printing process layering four colors, Cyan (blue), Magenta (red), Yellow, and Key (black), often referred to as the CMYK model, onto a substrate. The final image relies on the combination of these four colors and halftones to create an optical effect appearing as an unlimited range of colors.

Gloss

A term describing a bright, shiny finish. A look that is considered more popular than a traditional matte one.

Gloss Finish

 A varnish or laminate that distinctly reflects light imparting a shine or luster to the surface.

Grade Label

Labels that come into direct or indirect contact with food and must meet strict government standards for inks and adhesives. The US Food and Drug Administration (FDA) and the European Commission (EC) established and enforced these standards.

High-Density Co-Ex Blend Polyethylene Film

An additive-free bag material providing exceptional strength and clarity, making it an excellent choice for vacuum applications such as food containers or other rigid goods that need protection from damaging airflow.

Knockout Printing

A printing technique where the background color is "knocked out" of the design, leaving only the foreground color. This technique creates high-contrast prints with a sharp, clean look. It can be used to create labels with multiple colors without the need for multiple print runs resulting in an efficient and cost-effective printing method that is well suited for a variety of applications.

Label Repeat

The distance from the top of one label to the top of the next label, including any needed edge space between each label.

Label Structure

The ordered layers of materials in a complete label construction. These typically include release liner, release coating, adhesive, facestock, printing ink, and lamination or UV coating.

Linear Low-Density Polyethylene (LLDPE) Film

LLDPE film is impact and puncture resistant with excellent flexibility. It is used for pouches and stretch wrap and can be recycled into composite flooring, lumber, or new plastic films.

Low-Density Polyethylene Film

Film made from Low-Density Polyethylene (LDPE) resins and used in applications such as food storage bags, liners, and flexible packaging. It is known for its clarity, density, strength, and printability.

Mail Merge

A process used to print labels with a standard layout and placeholders for variable information. The variable information comes from a data source containing individual data for each label, such as addresses or personalization details.

Matte Finish

A surface texture usually smooth, even, and free from shine or highlights.

Natural Colored Labels

A label that has not been treated to change its color; the natural color of the face material is the label's color. Kraft labels are one popular example of natural colored labels since the wood pulp used in their production is naturally brown.

Onsert

Also known as an Expanded or Extended Content Label (ECL), an onsert is a booklet or pamphlet style label used to add more information than can fit in a single layer of available space. They require a permanent adhesive to attach to the primary package and a repositionable microsphere adhesive allowing the onsert to be opened for viewing and resealed.

Overlamination

A transparent film applied to the face material to improve its appearance or provide a protective layer. The overlaminate can have a gloss, matte, or textured finish and is generally done on-press during manufacturing or may be completed in a later, separate process.

Permanent Adhesive

An adhesive with a high initial tack, which adheres securely to a substrate, making it difficult to remove and leaving residue behind. A permanent adhesive will have a “peel adhesion” value of 20-28 N/25mm (1”).

Permeability

The permeability of a material is related to its porosity and can determine how much ink or adhesive will soak into the material. Permeable paper is ideal for high-speed printing. Poor permeability can result in smudging, poor adhesion, and poor dimensional stability.

Plate

Usually associated with flexographic and offset printing and used to transfer one ink color at a time onto the desired facestock. Printing plates are not required with digital printing.

Polypropylene Film

A low-cost thermoplastic of high clarity, high gloss, and good tensile strength.

Pressure Sensitive

Referring to labels that only require manual pressure to be applied for adhesion.

Release Liner

The paper or film bottom layer of a pressure-sensitive label. It is coated with a release agent allowing it to be easily removed when the label is ready to be applied. Typical release liner materials include polyester, silicone- or polyethylene-coated papers, or glassine.

Removable Adhesive

An adhesive with low initial tack. It adheres securely to the substrate but removes easily, leaving no adhesive residue. The “peel adhesion” value for a removable adhesive is less than 19 N/25mm (1”).

Repositionable Adhesive

An adhesive that allows labels to be removed and repositioned without damaging the substrate and leaving no residue behind. While most adhesives will reach permanent adhesion at some point, these may be treated to extend the time taken to reach permanent adhesion or prevent permanent adhesion from ever being achieved.

Reverse and Subsurface Printing

When the printed surface of a transparent face material is layered with adhesive, trapping the print between the material and the adhesive. The printing often utilizes a reverse or mirror image to have the correct orientation when viewed through the transparent face material.

Rubber-Based Adhesive

An adhesive with natural or synthetic rubber as its base material. It works particularly well in low temperatures and adhering to plastics. It is less expensive than acrylic or silicone adhesives, but it is more susceptible to UV light, high temperatures, and moisture.

Rust/Corrosion Inhibitor Film

A film with chemical additives that emit odorless, non-toxic vapors producing a rust-resistant barrier. This treated film protects against dirt, moisture, and corrosion.

Screen printing

Forcing ink through a screen, blocked by design stencils, allowing one color at a time to be applied to a substrate. This process is typically used for durable thick caliper films or textiles.

Shrink Sleeve

A 360-degree printed label typically made of plastic or polyester film and can be used on almost any container material and shape as they shrink to conform to the vessel when heat is applied. They are also often used as a built-in tamper-evident solution.

Solventless Adhesive Lamination

Applying a solventless adhesive to one or more substrate layers and then bonding them together with a heated nip roller.

Specialty Labels

A variety of special-use labels including, but not limited to, magnets, static clings, scratch-off, scratch and smell, glow in the dark, and variable data printed. These labels typically involve unique adhesives, coatings, and cutting or finishing methods.

Splice

Taping two rolls together with a clean cut between the labels and a single piece of tape on the back of the liner to form one long, continuous roll.

Spot varnish

Varnishing specific label sections, leaving some surface area exposed.

Static Dissipative Film

A coated plastic film used to protect products or environments susceptible to static electricity. They allow electrical charges to flow to ground more slowly, preventing discharges to or from human contact.

Tamper Evident Labels

A label designed to show evidence of any attempt to remove or alter it, making it an essential security measure for many products. They are also known as tamper-proof labels, security seals, security tape, and void seals. They are used in a variety of industries such as food and beverage, pharmaceuticals, medical devices, and electronics for a variety of purposes, including asset tracking, product authentication, brand protection, warranty management, and even crime scene investigation.

Tooling

The cylinders, dies, and plates needed to run each job.

Topcoat

A layer added to film materials to help the ink bond to the film surface. Topcoats can also add sheen or opacity to a label.

UV Varnish

Varnish that is cured using UV light. This varnish adds a surface finish and protective coating but does not necessarily protect the label stock from the harmful effects of UV light exposure.