Questions? Feedback? powered by Olark live chat software GLOSSARY – Letter Jacket
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Artwork - A general term used to describe photography, negatives, drawings, or electronic files prepared to illustrate printed matter.


Bleed - In printing, an image that extends off the edge of the page or envelope. Envelopes with bleed generally must be printed before they are folded, since the fold line runs through the printed image.

Bar Code - Used by the Postal Service to speed mail processing. Generated by the Post Office as mail passes through OCR scanners or pre-printed by the manufacturer. If not pre-printed, space must be available on the bottom right of the envelope for the bar code.

Booklet - 1) A large, open side envelope for catalogs, annual reports, and brochures. This style is gaining popularity over traditional Catalog (Open End) envelopes because it can be used with automatic inserting machines. 2) Also refers to Commercial Open Side envelopes with two side seams.

BRE - Stands for Business Reply Envelope. Normally printed one color with standard business reply copy.

Bitmap (BMP) - A bitmap or raster graphic is a digital image made up of dots. Each dot is assigned a different color. Bitmap images look best when they are used in the actual size they were created. When enlarging these files the image becomes distorted. See Raster Art Files.


CMYK - Cyan(C), Magenta(M), Yellow(Y), Black(K) these are the four process colors used for printing full color

Catalog - Describes a large Open-End envelope usually with a center seam.

Commercial - General term for the most common style of business envelopes. Open Side usually with diagonal seams.

Corner Card - Return address and other identification of the sender in the upper left-hand corner.


DPI - dots per inch, used to measure how many dots are in a linear inch - the resolution of an image. The higher the dpi the better the resolution.

Diagonal Seam - Seam style frequently used in Commercial Open Side envelopes, invitation and baronial envelopes. It’s name is derived from the seam running from the back corner of the envelope diagonally to the middle.

Die - Precision tool used to cut out envelope blanks, windows or other shapes.

Duotone - A common printing technique by which a halftone is printed in two ink colors, most often black and another color.


EPS - Encapsulated Post Script is a standard graphics file format.


Floodcoat - To print an envelope blank completely with ink. This process can only be done before the envelope is folded.

Face - The side of the envelope without the seams.

FIM - Stands for “Facing Identification Markings” - pre-printed bars on the face of the envelope, as specified by the Postal Service to expedite the automated processing of Business Reply Mail. The vertical bars are located at the top right corner of the envelope.

Four Color Process - Printing that uses 4 colors C(cyan), M(magenta), Y(yellow), K(black) to produce full color images.


Gum - An adhesive made with a plant base to seal paper envelopes. Some gums take moisture to seal, others such as latex gums will adhere to themselves.

GIF - Graphics Interchange Format. A bitmap image format.

Gripper Margin - An unprinted space allowed for the grippers on a printing press to grip the envelope. The margin is generally a minimum of 3/8”.


Halftone - Picture with gradations of tone, formed by dots of varying sizes in one color.


Indicia - Postage permit located on the upper right corner of an envelope which is pre-printed and requires no postage stamp.

Inside Tint - Printed design on the inside of the envelope. Used for added opacity and/or for graphic interest.


Jet Printing - A general term for printing presses set up to print already manufactured envelopes. Allows for fast, high quality turnaround. Can print screens up to 133 lines per inch.

JPG or JPEG - Stands for Joint Photographics Experts Group. A file format for the compression of high quality photographic digital images. 


Latex - An adhesive used to seal envelope flaps which sticks to itself. It is usually placed on flap and back of the envelope. When the two gum surfaces meet, it seals. No moisture is required.

Litho - A generic term for any printing process in which the image area and the non-image area exist on the same plate and are separated by a chemical repulsion. Usually oil based offset printing.


Open End - Style of envelope in which the opening is on the shorter side. 

Open Side - Style of envelope in which the opening is on the longer side.

Offset - A variation of the word “setoff”. The unintentional transfer of ink from one printed envelope to another when the two touch. Usually caused by heavy ink coverage, certain colors or too much pressure.


PMS - Pantone Matching System. A color matching systems used by printers to print spot colors (see Spot Colors), but not process colors which must use the 4 colors of CMYK. PMS colors have their own name or number to ensure that your colors are the same each time you print.

Patch Material - Translucent or clear material covering windows. Made from plastic or paper.

Peel & Seal - Term used for adhesive which is exposed by peeling away coated release paper. Will adhere without moisture.  Also called PNS.

PDF - Portable Document Format by Adobe. This file format provides an electronic image of text and graphics that look like the printed document and can be viewed, printed and electronically transmitted.

PDF Proof - A electronic image of your file to see what it will look like when printed. Proofs are used to check all text and graphics before going to press. *Actual colors on a PDF proof may appear slightly different on different computer monitors.

PPI - Pixels per inch (see Resolution).


Raster Art Files - Raster (bitmap) files are made up of millions of tiny dots of various colors that are called pixels. Raster images have a fixed resolution, if enlarged they can lose image quality (resolution). Raster images should be designed at the size they will be printed. The most common type of raster art is a photograph. Common file formats are JPEG, TIFF, GIF, PNG, BMP. The most common software for raster files is Adobe Photoshop.

Resolution - Sharpness, clarity, quality of an image. Resolution is the number of pixels per inch (ppi). The more pixels the better the resolution and print quality. With fewer pixels the resolution and print quality may be poor due to the image being blurry and fuzzy.


Seam - The back of an envelope where it is glued together. Center Seam - on an Open End Catalog or Booklet where the seam runs down the middle of the back; Side Seam - on an Open End Catalog or Booklet where the seam is on the side of the envelope.

Size - The measurement in length and width of an envelope or window.

Split Seal Gum - Broken gum pattern on a seal flap to prevent “tabbing”. Gum is broken where flap covers the diagonal envelope seams; prevents flap from sticking to the back panel during storage in humid conditions.

Spot Color - A method of specifying and printing colors in which each color is printed with its own ink unlike process printing which used 4 inks (CMYK-cyan, magenta, yellow and black) to produce all other colors. Spot colors are more cost effective to use when printing one to three different colors.


Vector Art - Vector art is not made up of pixels like raster art (JPG, TIFF, etc) but are made up of paths defined by a start and end point, curves and angles. Vector art is resolution independent and can be reduced and enlarged in size without loss of image quality. Most common software for vector files is Adobe Illustrator.


Window Cutout - Cutout in the body of the envelope positioned to show mailing address, return address and/or special messages. Eliminates the duplication of effort and the potential for error in addressing envelopes. Usually covered with transparent window patch material.

Wove - Paper having a uniform surface and no discernible marks. Soft, smooth finish, most widely used envelope paper. Relatively low opacity, brightness and bulk. However, recent changes in paper making from acid to alkaline sheets have improved the brightness. Mostly run in white.