SIM Printing Supplies

Printing Glossary

Name: SIM Printing Supplies
Address: Yakuplu, 194. Sk. No:1 D:176, Beylikdüzü, İstanbul, 34000, TR
Telephone: +902126376249
Price range: $$

Essential terms from the world of printing and press

AM Screening: The traditional halftone screening method where dots are arranged at fixed intervals and their size (amplitude) varies according to color density.
Anilox Roller: A precision ink transfer roller used in flexo and screen printing, coated with fixed geometric cells. Cell volume determines the amount of ink transferred.

Blanket (Offset Blanket): The rubber-coated cylinder covering in offset printing that transfers ink from the plate to the paper. Its quality and compressibility directly affect print quality.
Bleed: Extending design elements beyond the page edge to account for cutting tolerance. Standard bleed is 3–5 mm.

Calibration: The process of bringing a press, monitor, or other device to a known reference state. Regular calibration is essential for maintaining color consistency and print quality.
Choke and Spread: Trapping methods: Spread enlarges a light object against a dark background; Choke grows the background into the object. Both hide registration errors.
CMYK: Four-color printing system consisting of Cyan, Magenta, Yellow, and Key/Black. The standard color model in offset printing.
Coated Paper: Paper coated with clay, calcium carbonate, or similar materials on its surface. The smooth surface enables high-resolution printing and vivid colors.
Color Consistency: The capacity to produce the same color results for the same job at different times, on different machines, or at different facilities. Verified through Delta E measurements.
Color Gamut: The total range of colors a reproduction system (monitor, printer, etc.) can produce. CMYK offset printing gamut is narrower than an RGB screen.
Color Management: The system and processes ensuring consistent color reproduction across different devices such as monitors, scanners, and printing presses.
Color Separation: The process of splitting a color image into CMYK components or special colors. Each channel corresponds to a separate printing plate.
Color Temperature: A measure expressing the color of a light source in Kelvin (K). For print approval, standard viewing booth light must be D50 (5000K) or D65 (6500K).
CTP (Computer to Plate): Technology that directly writes the printing plate from a digital file using a laser. Eliminates the film stage, providing sharper plates and a faster press process.

Delta E (ΔE): Unit measuring the perceptual difference between two colors. ΔE < 2 indicates a difference indistinguishable by the human eye; critical for print quality assessment.
Densitometer: A device that measures ink density on a printed surface. Used for quality control and maintaining standard ink values.
Digital Printing: A printing method where output is produced directly from a digital file without the need for printing plates. Ideal for short runs and variable data; uses inkjet or laser technology.
Dispersion Varnish: A water-based polymer dispersion varnish applied in the press's coating unit or a separate coater. Offers fast drying and an eco-friendly profile.
Dot Gain: The condition where ink dots print larger than intended in the design. 10–20% dot gain is normal; ICC profiles are prepared to compensate for this value.
Duplex Printing: Printing on both sides of the sheet. In sheetfed presses, front and back are printed in separate passes; perfector presses print both sides in a single pass.

Embossing: A finishing technique that creates a three-dimensional raised area on paper or board using a die. Debossing works in the opposite direction, creating a recessed effect.

Flexography: A high-speed rotary printing method using flexible rubber or polymer plates. Widely used for packaging, labels, and corrugated cardboard.
FM Screening (Stochastic): A screening method where dot sizes remain constant but are placed randomly (stochastically). Eliminates moiré and is suited for very fine detail reproduction.
FOGRA: Germany-based Graphic Technology Research Institute. The organization that defines European offset printing standards (FOGRA39, FOGRA51, etc.) and publishes ICC profile characterization data.
Fountain Solution: A water-based solution in offset printing that prevents ink from adhering to non-image areas. pH and conductivity values must be regularly monitored.

GRACoL: General Requirements for Applications in Commercial Offset Lithography. A US-based commercial offset printing standard defining paper and ink values.

Halftone: The method of simulating continuous-tone images using dots of varying sizes. Since printing presses cannot produce true continuous tones, halftone makes color gradations possible.
Hot Foil Stamping: A finishing technique where metallic or holographic foil is transferred to the printed surface using heat and pressure. Provides gold or silver brilliance on luxury packaging, invitations, and labels.

ICC Profile: A file in International Color Consortium format that characterizes a device's color properties. Used in color conversions to ensure accurate color reproduction in print.
Imposition: A prepress operation that correctly arranges page sequences and orientations on both sides of the print sheet so that when folded it forms a book or brochure.
Ink Distribution: The homogeneous spreading of ink throughout the printing system. Uneven distribution leads to color variations (density variation) and banding effects.
Ink Drying: In offset inks, drying occurs through oxidative polymerization, absorption, and evaporation. Drying speed depends on ink formulation, paper type, and environmental conditions.
Ink Emulsification: The partial uptake of fountain solution water into offset ink during printing. Uncontrolled emulsification degrades print quality; the ideal emulsification rate is 15–26%.
Ink Film: The thickness of the ink layer formed on paper or another substrate during printing. In offset, typically 0.5–3 microns; thickness directly affects color density.
Ink Roller Train: The series of rollers in an offset press that evenly distributes ink from the ink fountain to the printing plate. Comprises distribution, form, and transfer rollers.
Ink Viscosity: The property expressing a fluid's resistance to flow. In offset inks, viscosity is adjusted according to press speed and ambient temperature; too high or too low causes printing defects.
Ink-Water Balance: The critical balance between ink and fountain solution quantities in offset printing. Disruption leads to defects such as toning, scumming, or washout.

L*a*b* Color Space: CIE-defined color space based on human visual perception. L* represents lightness, a* green-red, and b* blue-yellow axes. Universal reference standard for color measurement.
Lamination: The process of bonding a thin plastic film to printed paper or board. Available in matte, gloss, or soft-touch finishes; adds durability and visual appeal.
Letterpress: One of the oldest printing techniques, where ink is transferred directly from a raised surface to paper. Today preferred for luxury invitations and artistic prints.

Moiré: An unwanted pattern or grid effect appearing in print due to incorrect halftone screen angles. Prevented with correct screen angles (C:15°, M:75°, Y:90°, K:45°).

Offset Printing: An indirect printing method where ink is transferred from a plate to a rubber blanket and then to paper. The foundation of commercial printing due to its high quality and speed.
Overprint: A setting where one color layer prints on top of another rather than knocking it out. Typically applied to black text; color mixing must be carefully considered.

Pantone Bridge: A reference guide showing the CMYK equivalents of Pantone spot colors and how they appear on screen. Enables designers and printers to use a common language.
PANTONE Color: Standardized spot colors defined by the Pantone Matching System (PMS). Each color carries a unique code ensuring consistent color reproduction in print.
Paper Weight (GSM): The weight in grams of one square metre of paper. Common uses: 80 g/m² office paper, 115–170 g/m² coated magazine paper, 250–350 g/m² cardboard.
Prepress: All design, color separation, imposition, and proofing processes that take place before the plate goes to the press. CTP and RIP are the key technologies of this stage.
Press Speed: The number of sheets or meters a press prints per hour. Higher speed means shorter turnaround, but requires careful attention to ink drying and color balance.
Print Standardization: Adhering to defined parameters (ink density, dot gain, white point, etc.) to make the print process consistent and measurable. ISO 12647 series is the foundational standard.
Printing Plate: A surface carrying the print image, typically made from aluminum or polymer. In offset printing produced using CTP (Computer to Plate) technology.
Profile Assignment: Assigning a source ICC profile to an image, defining the color space the image is in. Incorrect assignment leads to color shifts and printing errors.
Proof: A color and content verification copy prepared for client approval before going to press. Soft proof is digital; hard proof is physically produced.

Registration: In multicolor printing, the precise alignment of each color layer with the others. Registration errors cause color fringing and blurry prints.
RGB: Color model based on mixing Red, Green, and Blue light. Used in screens and monitors; must be converted to CMYK before printing.
RIP (Raster Image Processor): Software or hardware that converts vector and pixel-based digital files into raster (dot) data for the output device. Color management and screening also occur within the RIP.
Rosette: The flower-like micro pattern formed by CMYK halftone dots merging at correct angles. An unavoidable feature of correct screen angles, it is a sign of quality printing.

Safe Zone: An inner zone kept at a defined distance from the page edge to ensure critical content (text, logo) is not damaged during trimming. Typically 3–5 mm margin is recommended.
Screen Printing (Serigraphy): A printing method where ink is pushed through a stencil (silk or synthetic mesh) onto the substrate. Applicable to textiles, plastics, glass, and metal.
Set-Off: The transfer of wet ink from a freshly printed sheet to the back of the next sheet in the pile. Prevented with anti-set-off spray powder and proper stacking.
Sheetfed Offset: A type of offset printing where individual sheets of paper are fed through the press. Preferred for short to medium print runs requiring high quality.
Soft Proof: A digital preview method that simulates the press result on a calibrated monitor instead of printing on paper. Saves cost and time.
Spectrophotometer: A precision instrument that objectively measures color by analyzing light wavelengths. Used in ICC profile creation and press calibration.
Spot Color: A custom color printed with a single premixed ink instead of CMYK halftone dots. Provides higher color accuracy and vibrant effects.

Tack: The adhesive resistance an ink exhibits as it splits between printing cylinders and blanket. High tack can cause paper picking; low tack leads to poor ink transfer.
Thin Ink Film Transfer: The precise control of the thin ink film transfer process between the printing units in offset. Managed by the ink roller train, this process is critical for color consistency.
Total Area Coverage (TAC/TIL): Keeping the sum of CMYK values within a defined upper limit. In offset, typically capped at 300–320%; exceeding this causes ink drying and set-off problems.
Trapping: A technique of slightly overlapping adjacent color areas to hide misregistration during printing. Two types: choke (shrinking) and spread (expanding).

UV Printing: A printing technology where ink cures (dries) instantly under ultraviolet light. Provides high gloss, strong fade resistance, and fast production.
UV Varnish: A high-gloss varnish that cures instantly under ultraviolet light. Strongly protects the printed surface against mechanical damage and moisture; available in matte or gloss.

Varnish: A transparent coating applied to a printed surface to protect it and enhance its aesthetic appearance. Types include dispersion, UV, and wet offset varnish.

Web Break: The tearing of the paper web in web offset printing due to high speed or tension. Causes significant material loss and press downtime.
Web Offset: A high-speed offset printing method where paper is fed from a continuous roll (web). Used for high-volume jobs like newspapers, magazines, and catalogs.
Wet-on-Wet Printing: Printing the next color immediately on top of a still-wet previous color layer without waiting for it to dry. Standard practice in multicolor presses; ink tack sequence is crucial.