The Print & Packaging Glossary

FlexoA metal or ceramic roller with a precisely engraved pattern of cells that holds a controlled, metered volume of ink. The anilox transfers a consistent ink film to the flexo printing plate. Cell volume (measured in BCM, billion cubic microns per square inch) determines how much ink is delivered per impression. See Flexographic Printing.

OffsetFinely ground starch powder sprayed onto freshly printed sheets in the press delivery unit to prevent the wet ink from transferring (setting off) to the back of the sheet above it in the delivery pile. Standard particle sizes: 15–20 micron for coated paper, 20–30 micron for uncoated. See Anti-Setoff Powder.

FinishingA water-based protective coating applied inline after printing by the last press unit or offline. Dries by evaporation and absorption. Provides moderate gloss (25–40 GU at 60°) and surface protection. Less vivid than UV coating but requires no UV lamp and can be applied to almost any paper. See Varnishes & Coatings.

Pre-PressThe digital file or physical original from which the printing plates are made. In modern production, artwork is a PDF/X-4 file containing all images, fonts, and colour specifications at the correct resolution and colour mode for the target press and substrate. See Pre-Press Complete Guide.

PackagingA machine-readable pattern of parallel bars and spaces (1D barcode) or a matrix of dots (2D barcode) that encodes product identification data. EAN-13 is the standard 1D barcode for retail products in India, registered through GS1 India. Barcodes must be verified to ISO 15416 (1D) or ISO 15415 (2D) before production. See Barcode Guide.

PaperThe weight of paper expressed as grams per square metre (GSM) in the ISO/metric system, or as pounds per 500 sheets of a specified parent sheet size in the US system. In India and all ISO-system countries, GSM is the standard. See GSM Explained.

FlexoThe unit of measurement for anilox cell volume in flexographic printing. Higher BCM = more ink delivered per impression. Standard anilox BCM values range from approximately 1.0 BCM for fine process colour work to 8+ BCM for heavy flood coat coverage. See Flexographic Printing.

FinishingThe method by which multiple printed pages or sections are held together to form a book, brochure, or catalogue. Principal methods: saddle stitching, perfect binding, case binding (hardcover), wire-O, PUR adhesive binding. Choice depends on page count, usage durability, and budget. See Binding.

OffsetA rubber-covered cylinder in an offset press that receives the ink image from the plate and transfers it to the substrate. The blanket's compressibility allows it to conform to slight substrate surface irregularities. Types: conventional (hard) and compressible. See Printing Blankets.

Pre-PressThe extension of background colours, images, or design elements beyond the trim line into the area that will be cut away after printing. Bleed ensures that if the cut deviates slightly from the trim line, no white paper edge is revealed. Standard commercial print bleed: 3mm on all sides. See Designing for Offset.

OffsetA defect in which freshly printed sheets stick together in the delivery pile because the ink has not fully dried before the next sheet is placed on top. Caused by insufficient anti-setoff powder, excessive ink coverage, slow-drying ink, or high humidity. See Anti-Setoff Powder.

PackagingA polypropylene film stretched in two directions (biaxially oriented) during manufacture, producing a clear, stiff, glossy film used extensively in flexible packaging and as a lamination film for printed paper and board. Available in gloss, matte, and speciality grades. See Lamination Film Types.

PaperThe reflectance of blue light (457nm wavelength) from a paper surface, expressed as a percentage. A measure of how white a paper appears under blue-rich lighting. Different from whiteness (which accounts for the full visible spectrum) and luminosity. High-brightness papers are preferred for photographic reproduction and premium printing. See Paper Measurement Tools.

PaperThe relationship between a paper's thickness (caliper) and its weight (GSM), expressed as cm³/g. High-bulk paper is thicker and more rigid at the same weight. Uncoated offset papers typically have higher bulk (1.2–1.5 cm³/g) than coated art papers (0.88–0.95 cm³/g). FBB board has higher bulk than SBS at the same GSM, making it structurally stiffer per gram.

PaperThe physical thickness of a sheet of paper or board, measured in millimetres or microns under a defined measurement pressure (ISO 534 specifies 100 kPa). Caliper and GSM are related but not directly proportional, two papers of the same GSM may have different calipers depending on their bulk. Caliper is the critical specification for die-cutting crease rule depth. See Caliper Instruments.

OffsetA press defect in which ink deposits in the non-image (background) areas of the plate, producing a faint overall tint on the printed sheet. Caused by inadequate fountain solution, excessive ink tack, or contaminated fountain solution. Closely related to scumming but typically more diffuse. See Print Defects Guide.

PaperThe FSC certification that tracks paper and board from forest to printer. For a printed piece to carry the FSC logo, every organisation in the supply chain must hold a current FSC Chain of Custody certificate audited by an independent third party. See Sustainability.

Pre-PressA trapping technique in which the background colour is reduced (choked inward) at the boundary with a foreground object, creating a small colour overlap zone that prevents white gaps from appearing due to misregister. The counterpart is spread (expanding the foreground). See Trapping & Overprint.

ColourThe three-dimensional colour space defined by the Commission Internationale de l'Éclairage in which all visible colours are described by three values: L* (lightness 0–100), a* (red-green axis), and b* (yellow-blue axis). Used for all spectrophotometric colour measurement in print. ΔE (delta E) is the mathematical distance between two colours in this space. See Spectrophotometer.

ColourThe four process ink colours used in full-colour printing: Cyan, Magenta, Yellow, and Key (Black). CMYK is a subtractive colour model, inks absorb (subtract) specific wavelengths of light. By varying the percentage of each ink in a halftone pattern, the full visible colour gamut of the press is approximated. See CMYK.

PaperPaper that has been coated with a layer of mineral pigments (typically calcium carbonate and kaolin clay) to improve surface smoothness, ink holdout, and colour reproduction. Types by finish: gloss, matte, silk, and satin. Gloss coated paper achieves the highest colour reproduction quality. See Paper Coatings & Surfaces.

MeasurementA strip of solid, tint, and overprint patches printed in the slug area outside the trim line. Used by press operators and quality inspectors to measure density, dot gain, trapping, and colour balance with a densitometer or spectrophotometer during and after the run. Also called FOGRA media wedge or Brunner reference strip.

ColourThe complete range of colours that a specific device or process can reproduce. CMYK offset on coated paper has a smaller gamut than a calibrated RGB monitor, saturated blues, vivid greens, and fluorescent colours that are visible on screen may be outside the press gamut and will shift when converted to CMYK. See Colour Management.

ColourThe system of ICC profiles, colour transforms, and calibrated devices that ensures consistent, predictable colour reproduction across different input and output devices. A managed colour workflow ensures that what is seen on screen in soft proof matches the printed contract proof, which matches the press output. See Colour Management.

OffsetThe electrical conductivity of fountain solution, measured in µS/cm (microsiemens per centimetre) or mS/cm, indicating total dissolved solids. Fresh fountain solution has a defined baseline conductivity; conductivity rising during a run indicates contamination accumulation. A rise of more than 50% above baseline is grounds for solution change. See Fountain Solution.

Pre-PressA calibrated physical proof produced on a colour-managed inkjet proofing system that simulates press output on a specific substrate, evaluated under D50 lighting. The signed contract proof is the legal colour reference for the production run, the press must produce output within an agreed ΔE tolerance of the contract proof. See Proofing.

PackagingA layered board structure consisting of one or more wavy fluted inner layers sandwiched between flat liner sheets. Provides high compression strength at low weight. Used for transport packaging, retail-ready packaging, and point-of-sale displays. Grades: E, B, C, and BC double-wall flute. See Corrugated Packaging.

Pre-PressThe digital plate imaging process in which an imagesetter or platesetter exposes the printing plate directly from a digital file via laser, bypassing film. CTP produces more precise dot reproduction than film-based platemaking. Types: thermal CTP (most common in India) and violet/photopolymer CTP. See Plate Making.

GravureIn gravure printing, a chrome-plated copper cylinder with cells engraved or etched into its surface. Each colour has a dedicated cylinder. Cylinders are expensive (₹15,000–₹40,000 per colour) and are the primary reason gravure requires long run lengths to be economical. See Gravure Printing.

ColourThe standard illuminant for evaluating printed colour, a simulated daylight with a colour temperature of approximately 5,000K. All contract proof evaluation, press OK comparison, and colour communication must occur under D50 light. Fluorescent office lighting, which is typically 3,500–4,000K, distorts colour perception and makes colour-to-proof comparison unreliable. See Proofing.

FinishingA post-press technique that presses a relief die into the substrate surface to create a recessed (sunken) impression, the opposite of embossing. The design element appears below the surrounding surface. Often combined with foil stamping or printing for added dimension. See Embossing & Debossing.

ColourThe numerical measure of the total colour difference between two colours in L*a*b* colour space, calculated as the three-dimensional distance between two colour points. ΔE below 1.0 = imperceptible. ΔE 1–3 = perceptible to trained eye. ΔE 3–5 = clearly visible. ΔE above 5 = unacceptable for most brand colour applications. See Spectrophotometer.

MeasurementAn instrument that measures the optical density of a printed ink film, how much light the ink absorbs. Used for press-side ink density control during production runs. Filters: Status E (ISO) for European/Indian production, Status T (ANSI) for North American production. ISO 12647-2 targets are specified for Status E. See Densitometer.

MeasurementA logarithmic measure of how much light a printed ink film absorbs. Expressed as D = log₁₀(1/reflectance). Higher density = more ink on the substrate. ISO 12647-2 target densities for coated paper (Status E): Cyan 1.45, Magenta 1.45, Yellow 1.05, Black 1.75. See ISO 12647-2.

FinishingA post-press operation in which a custom steel rule tool cuts and creases printed board or paper into a defined shape. Used to produce folding carton blanks, labels, shelf-ready packaging, and custom-shaped printed items. See Die Cutting.

PackagingThe technical drawing that defines the exact cutting, creasing, perforating, and scoring lines for a packaging structure. The dieline is typically provided by the structural design team or the converter, and the print artwork is placed on top of it for alignment verification. See Folding Cartons.

DigitalPrinting technology that transfers ink or toner directly from a digital file to the substrate without physical plates. Principal technologies: electrophotography (laser/toner) and inkjet. Digital printing is economical for short runs (typically below 500–1,000 copies) and enables variable data printing (personalisation). See Digital Printing.

Pre-PressThe standard business envelope format (110×220mm) designed to accept an A4 sheet folded into thirds. The standard Indian business envelope format for letterheads, invoices, and direct mail. See Paper Sizes.

GravureA thin, flexible steel or plastic blade pressed against the gravure cylinder that wipes excess ink from the cylinder surface, leaving ink only in the engraved cells. Doctor blade pressure, angle, and material directly affect print quality, a worn or incorrectly set doctor blade causes streaking, uneven ink, and excessive cylinder wear. See Gravure Printing.

OffsetThe increase in the size of a halftone dot from its specified value in the digital file to its actual printed size on the substrate. Expressed as a percentage: a 50% dot in the file printing as a 68% dot on press = 18% dot gain. ISO 12647-2 specifies a target dot gain of 18% at 50% screen for coated paper. See ISO 12647-2.

Pre-PressA measure of printer or imagesetter output resolution, the number of individual dots per linear inch. Not the same as PPI (pixels per inch) for digital images. A 175 LPI screen ruling requires approximately 2,400 DPI imagesetter resolution to represent the smallest screen dots accurately. See Screen Ruling.

PaperA two-layer carton board with a white coated surface on the front and a grey (recycled) back. Lower quality and lower bulk than SBS or FBB. Used for economy packaging where appearance of the reverse is not critical. Common in Indian FMCG, dairy, and commodity packaging. See Paper & Board Grades.

PackagingThe 13-digit barcode standard used on retail consumer products worldwide, including India. Registered through GS1 India (formerly EAN India). Standard dimensions at 100% magnification: 37.29mm wide × 25.93mm high. Minimum magnification: 80% (29.83mm wide). Barcode bars must be black or dark colour on a white or yellow background. See Barcode Guide.

FinishingA post-press technique that uses a matched male-female die set to press the substrate, creating a raised (embossed) impression of the die design. Types: blind emboss (no ink or foil), registered emboss (aligned with a printed or foiled area), and combination emboss-and-foil. See Embossing & Debossing.

PackagingIndia's regulatory framework under the Plastic Waste Management Rules 2022 that requires brand owners (producers) to take responsibility for the collection and recycling of plastic packaging they place in the market. EPR obligations are managed through registered Producer Responsibility Organisations (PROs). See Sustainability.

OffsetThe pressure between the blanket cylinder and the impression cylinder (or the plate cylinder and the blanket cylinder) that enables ink transfer. Correct impression pressure is critical, too light and ink transfer is incomplete; too heavy and dot gain increases and blanket wear accelerates.

PaperA multi-layer carton board with white coated outer layers and a mechanical pulp (TMP or GW) middle layer. The mechanical pulp provides high bulk, making FBB stiffer at the same GSM than SBS. FBB is the dominant board grade for premium FMCG packaging globally and increasingly in India. See Paper & Board Grades.

FlexoA rotary relief printing process using flexible photopolymer or rubber plates and fluid, fast-drying inks. Dominant process for flexible packaging (films, laminates), labels, and corrugated post-print. Central impression (CI) flexo is the high-quality variant used for premium flexible packaging. See Flexographic Printing.

FinishingA coating or varnish applied over the entire printed surface (as opposed to spot application). Flood UV coating produces a high-gloss, uniform surface without contrast between coated and uncoated areas. See Varnishes & Coatings.

PackagingThe wavy inner layer of corrugated board. Flute grades defined by size: A (the tallest, most cushioning), B (thin, good printing surface), C (standard transport case), E (very fine, good for printing, used for small cartons), and F/G/N (microflute, for high-quality retail packaging). See Corrugated Packaging.

Pre-PressA halftone screening method where all dots are the same size but placed randomly (stochastically), tone variation is achieved by varying dot frequency rather than dot size (as in AM screening). FM screening eliminates moiré patterns and produces smoother tonal transitions but requires more precise ink-water balance control. See Screen Ruling.

FinishingA finishing process that applies a thin metallic or pigmented foil to the substrate surface using a heated die under pressure. The foil bonds to the substrate where the die makes contact. Available in metallic (gold, silver, copper), pigment, holographic, and matte finishes. See Foil Stamping.

PackagingA packaging structure made from printed and die-cut paper board that is erected (folded) at the filling point. The dominant packaging format for Indian pharmaceutical, FMCG, food, and personal care products. Principal board grades: SBS and FBB. See Folding Cartons.

Pre-PressThe inclusion of font data within a PDF file, ensuring that the text renders correctly on any system regardless of whether the original font is installed. PDF/X-4 requires all fonts to be embedded. Fonts not embedded will be substituted by the press room's RIP, potentially changing layout, spacing, and appearance. See Typography for Print.

OffsetThe water-based solution used in offset printing to wet the non-image areas of the plate, preventing them from accepting ink. Correct pH (4.5–5.2) and conductivity are critical for ink-water balance, dot gain, and ink drying. See Fountain Solution.

PackagingThe regulatory body governing food safety standards and labelling requirements for packaged food products sold in India. FSSAI licence number (14 digits) and FSSAI logo are mandatory on all packaged food product labels and cartons. See India Packaging Regulations.

PaperAn international non-profit organisation that promotes responsible forest management through a chain-of-custody certification system. FSC-certified paper and board can carry the FSC logo, confirming that the material came from responsibly managed forests through a verified supply chain. See Sustainability.

OffsetA print defect in which a faint duplicate image appears in an unexpected location on the printed sheet, caused by ink starvation in the duct or the ink form rollers. Occurs because ink is depleted faster in high-coverage areas, leaving less ink available for the next impression in the same roller cycle. See Print Defects Guide.

FinishingThe specular reflectance of a surface, how much light is reflected in the mirror direction. Measured in Gloss Units (GU) at a specified angle (20°, 60°, or 85°). Typical values: gloss lamination 65–85 GU at 60°, matte lamination 8–18 GU, spot UV 85–100 GU. See Gloss Testing.

MeasurementAn instrument that measures surface specular gloss. Projects a beam at a defined angle (20°, 60°, or 85°) and measures reflected light. The 60° angle is the default for most print and packaging surfaces. See Gloss Meter.

PackagingA system of manufacturing quality standards required for pharmaceutical packaging converters in India. GMP-certified press rooms are audited to confirm that production controls, materials traceability, and contamination prevention meet Schedule M standards under the Drugs and Cosmetics Act. See Packaging Buyer's Guide.

PaperThe predominant direction of paper fibre alignment during manufacture, determined by the direction the paper travels through the Fourdrinier wire. Paper folds more crisply, curls less, and accepts binding adhesive better when the grain runs parallel to the spine. Long grain (LG) = grain parallel to the long side of the sheet. Short grain (SG) = grain parallel to the short side. See Grain Direction.

GravureA rotary intaglio printing process where ink is carried in recessed cells engraved into a cylinder. The cylinder rotates in an ink trough; a doctor blade wipes excess ink from the surface; the substrate contacts the cylinder under impression pressure, drawing ink from the cells. Dominant process for premium flexible packaging in India. See Gravure Printing.

PackagingThe Indian member organisation of GS1, the global body that administers barcode number assignments. All EAN-13 barcodes for retail products sold in India must be registered through GS1 India. A GS1 company prefix licenses a range of GS1N numbers from which individual product GTINs can be created. See Barcode Guide.

PaperThe standard metric unit of paper weight, the weight in grams of one square metre of the material. The ISO A series paper size system is anchored to GSM: an A0 sheet (1 m²) of 80 GSM paper weighs exactly 80 grams. Used universally in India and internationally. See GSM Explained.

PackagingThe GS1 standard identification number for a product, a 14-digit number that uniquely identifies a product across all markets and trading partners. EAN-13 encodes a 13-digit GTIN. Assigned by the brand owner from within their GS1 company prefix. See Barcode Guide.

Pre-PressThe technique of converting continuous-tone images (photographs) into a pattern of dots of varying size (AM screening) or varying frequency (FM screening) that creates the visual impression of tonal variation when printed. Offset printing can only print a solid ink film or no ink, halftoning creates the appearance of intermediate tones. See Screen Ruling.

PackagingAn analytical test method used to measure residual solvent levels in printed flexible packaging. Printed film is sealed in a container, heated to release volatile solvents into the headspace, and the headspace is analysed by gas chromatography. Residual solvent limits: typically 5 mg/m² total, zero toluene for food packaging. See Food-Safe Inks.

OffsetA small circular spot defect consisting of a solid dot surrounded by a white halo, caused by a particle of dried ink, paper dust, or foreign material adhering to the plate or blanket and preventing ink from transferring in that area. The most common contamination defect in offset printing. See Print Defects Guide.

FinishingA UV coating applied in multiple passes to build up a three-dimensional raised effect on the printed surface. Creates a tactile quality cue by producing a visible and feelable elevation above the surrounding surface. Used for premium packaging and luxury print applications. See Varnishes & Coatings.

FinishingSee Foil Stamping. Hot foil uses a heated die to bond metallic or pigmented foil to the substrate. Distinguished from cold foil, which uses adhesive without heat. See Foil Stamping.

ColourA standardised data file that describes the colour characteristics of a device or colour space, how it reproduces colour, what its gamut is, and how its values map to device-independent colour coordinates. ICC profiles are the foundation of colour management. Key profiles for Indian offset: ISOcoated_v2 (Fogra39) and PSO Coated v3 (Fogra51). See Colour Management.

Pre-PressThe arrangement of pages on a press sheet so that when the sheet is printed and folded, the pages appear in the correct sequence. An 8-page A4 brochure requires 4 pages per side of an SRA3 sheet, imposition planning determines which pages go where for each binding method. See Imposition.

OffsetThe press cylinder that provides the counter-pressure to the blanket cylinder, pressing the substrate against the blanket to enable ink transfer. The impression cylinder has no printing function, it only provides pressure. Correct packing and pressure are critical for uniform ink transfer across the sheet.

InkThe resistance of an ink film to splitting, its stickiness between two surfaces. High-tack inks transfer cleanly from smooth coated paper but may cause paper picking (surface delamination) on rougher uncoated stock. In multi-unit offset presses, inks must be printed in decreasing tack order (first down = highest tack) to ensure correct trapping. See Offset Inks.

FinishingFinishing operations (varnish, coating, lamination, die-cutting) performed in-line within the printing press in a single pass, rather than as separate offline operations. Inline finishing reduces handling, improves registration between print and finishing, and increases production speed. See Varnishes & Coatings.

OffsetAn alcohol added to offset fountain solution (typically 5–15%) to reduce surface tension, improve plate wetting, and stabilise the ink-water balance. IPA evaporates rapidly, contributing to VOC emissions. Press rooms increasingly use IPA substitutes or IPA-free fountain solutions for environmental and health reasons. See Fountain Solution.

ColourThe ICC output profile for offset printing on coated paper to ISO 12647-2, characterised from Fogra 39L press characterisation data. The reference CMYK working space for coated paper commercial and packaging print in India and globally. Available free from eci.org. See Colour Management.

PackagingThe standard barcode for outer transport cases and shipping cartons, encoding a 14-digit GTIN. Typically printed on corrugated board. Standard dimensions: 137.84mm wide × 34mm high at 100% magnification. ITF-14 has larger modules than EAN-13 to compensate for lower print quality on corrugated surfaces. See Barcode Guide.

Pre-PressThe production document that accompanies a print job through the press room, specifying all production requirements: quantities, paper specification, colours, finishing, delivery details, and quality requirements. The job ticket is the internal instruction document used by the press room, distinct from the client's brief.

PaperA naturally occurring white clay mineral used as a coating pigment in paper manufacturing. Kaolin (aluminium silicate) provides a smooth, relatively matt surface when used alone. Often blended with calcium carbonate to adjust gloss level and improve opacity. See Paper Coatings.

Pre-PressWhen a foreground object removes (knocks out) the area of background colour beneath it, so that only the foreground colour prints in that zone, not both colours combined. The default behaviour for most design elements. The opposite of overprinting. White objects must always be set to knockout (never overprint). See Trapping & Overprint.

MeasurementA derived densitometric measure of shadow contrast: K = (Ds − D75) / Ds × 100%. Higher K values indicate better shadow detail separation. Minimum K = 35% for acceptable shadow quality on coated paper. Declining K during a run indicates ink film build-up reducing contrast between solid and shadow areas. See ISO 12647-2.

PaperAn unbleached paper made from sulphate pulp, characterised by its high tear and tensile strength. Brown kraft is the most common. White kraft uses bleached pulp. Used for carrier bags, industrial packaging, wrapping, and increasingly as an eco-packaging alternative to plastic. Prints well with flexo and offset but has lower ink holdout than coated paper.

PackagingA printed substrate applied to a product or container to convey brand identity, product information, and regulatory declarations. Principal types: pressure-sensitive self-adhesive labels (BOPP, paper), heat-shrink sleeve labels, and in-mould labels. See Labels.

FinishingThe bonding of a plastic film to a printed paper or board surface. Lamination protects the printed surface from scuffing, moisture, and handling, and modifies the surface finish (gloss, matte, or soft touch). Principal lamination film: BOPP. Methods: thermal (dry bond) and wet (solvent or water-based adhesive). See Lamination.

PackagingThe Indian regulatory framework under the Legal Metrology Act 2009 and Legal Metrology (Packaged Commodities) Rules 2011 governing mandatory declarations on packaged products sold in India, MRP, net quantity, manufacturer name and address, country of origin, and month/year of manufacture. See India Packaging Regulations.

ProcessA relief printing process in which ink is applied to a raised surface and pressed onto the substrate. The oldest major printing process. In modern production, letterpress is used for narrow-web label printing (flexo is an evolved form of letterpress) and specialty applications including hot foil stamping and embossing dies.

InkInk formulations in which all components, pigments, binders, photoinitiators, and additives, have been selected and tested for low migration potential through packaging materials into food. Mandatory for any food contact or near-contact packaging application. LM inks add approximately 15–30% to ink cost. See Food-Safe Inks.

Pre-PressThe number of rows of halftone dots per linear inch, the screen frequency or screen ruling. Higher LPI = finer dots = smoother tonal gradients but requires a smoother substrate and more precise ink control. Typical values: 85 LPI for newsprint, 133–150 LPI for coated paper, 175 LPI for premium coated. See Screen Ruling.

MeasurementAn ISO 13655 spectrophotometric measurement condition using D50 illumination that excites optical brightening agents (OBAs) in paper the same way as standard D50 viewing conditions. The reference measurement condition for ISO 12647-2 and modern colour management. M0 (incandescent) does not excite OBAs. Always specify M1 when measuring to ISO targets. See Spectrophotometer.

OffsetThe complete process of setting up a printing press for a specific job, mounting plates, setting ink zones, adjusting impression pressure, setting guides and grippers, achieving colour and register to the approved proof, and running up to production quality. Makeready time and the associated waste sheets are a fixed cost independent of run length, making offset less economical at very short runs. See Offset Printing.

FinishingA coating or lamination film that diffuses reflected light, producing a low-gloss, non-reflective surface. Typical gloss values: matte lamination 8–18 GU at 60°, matte varnish 10–25 GU. Matte surfaces show fingerprints more visibly than gloss and are more susceptible to scuffing. Often used as a background for spot UV contrast. See Lamination.

InkThe movement of ink components (pigments, binders, solvents, photoinitiators) from the printed surface through the packaging material into the food product. Measured as mg per dm² of packaging surface. EU regulation specifies overall migration limit of 10 mg/dm². Photoinitiators ITX and benzophenone are the most commonly restricted migrating substances in UV inks. See Food-Safe Inks.

OffsetThe displacement of one printed colour from its correct alignment relative to other colours. Visible as coloured fringes on edges, soft detail, and colour contamination in neutral tones. ISO 12647-2 specifies maximum misregister of ±0.1mm for coated paper offset. Causes: plate mounting error, paper stretch, gripper variation. See Register.

Pre-PressAn unwanted repeating pattern that appears when two regular grid patterns (halftone screen angles) interfere with each other. Prevented in four-colour offset by using specific screen angles for each CMYK separation: typically C 15°, M 75°, Y 90°, K 45°. FM (stochastic) screening eliminates moiré by using random dot placement. See Pre-Press Guide.

PackagingA densitometric measure of barcode quality, the difference in reflectance between the darkest bars and the lightest spaces in a barcode. Higher MRD = greater contrast = more reliable scanning. MRD is a component of the ISO 15416 barcode quality grading system. See Barcode Guide.

PackagingThe maximum price at which a packaged product may be sold to the consumer in India, as mandated by the Legal Metrology (Packaged Commodities) Rules. The MRP must be printed on the packaging as "MRP ₹____ (Incl. of all taxes)". It is illegal in India to sell packaged goods above the printed MRP. See India Packaging Regulations.

MeasurementThe mathematical formula used to calculate the actual dot area percentage (tone value) from density measurements: Dot Area = (1 − 10^−Dt) / (1 − 10^−Ds) × 100%, where Dt is the density of the tint and Ds is the density of the solid. Used by densitometers to calculate dot gain (TVI). See ISO 12647-2.