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Backbone
Also known as the "hub" or "spine". The supporting part of the binder or book to which the front and back covers are attached. In binders, it also serves as a support to which the ring metal is attached. It is the visible part of a binder or book while it is standing on a shelf.
Back plate
A plate made of metal or board with rivets pre-attached and inserted into the spine to provide concealed rivets.
Bevel edge
When the selection of cover board is excessively thick (i.e. 1/4"), the cover boards are generally beveled at the edge that goes into the hinge. Using excessively thick board will not allow the cover to close properly, but beveling rectifies this problem. The other three edges of the board may also be beveled, for aesthetic purposes only.
Binder's board
A single ply, tunnel dried solid board manufactured in a wide range of thicknesses (i.e. .060 to .250"). It is manufactured to no less that .9 density. The most popular thicknesses for loose leaf binders are .098 to .120".
Bone folder
A tool used by hand for turning material over the edges of board, tucking corners and creasing hinges. These processes are sometimes referred to as "boning in". While traditionally made of ivory or bone, bone folders are now available in plastic as well.
Caliper
Unit of measure used to express the thickness of board and paper products. Measured in thousands of an inch.
Casebound
See turned edge
Chipboard
The most common type of cover board used for looseleaf binders. It is a single-ply board in calipers up to approximately .030", or a multi-ply laminated board up to .120" thick. Chipboard has a very smooth surface, and is available with foam padding or unitized (front board, back board and back plate hinged together).
Corona discharge treatment
A method of rendering inert plastics such as polyethylene more receptive to inks, adhesives or decorative coatings by subjecting their surfaces to a high voltage electrical charge. This oxidizes the surface making the plastic more receptive to coatings.
Coverboard
See Coverboard FAQ.
Cover material
The material used to cover the entire outside surface of a binder or a book. A wide variety of cover material qualities, constructions and finishes are avaiable to provide the desired finished product. For more information, see woven and non-woven.
Cut flush
The earliest form of looseleaf binders, consisting of a material that forms a one-piece construction. In the early days, cut flush binders consisted of leather, hardboard, paperboard and latex impregnated boards. Newer binders are typically poly binders.
Debossing
A process using heat and pressure to smooth out an embossing present on a specific material. This may be done to provide a stamping or screening area for the desired graphics.
Embossing
A process using heat and pressure along with male and female dies to provide a raised three dimensional effects to the graphics.
Euro board
See Coverboard FAQ.
Foil stamping
A decorative technique using dies, heat, pressure and colorful foil. The desired graphics are transfered from a foil carrier to the surface of the cover material through the heat and pressure of the stamping press. Foil stamping is most often used in small areas where a metallic decoration is desired.
Gauge
Unit of measure used to express the thickness of thin materials, such as vinyl. Measured in thousands of an inch.
Glue machine
A glue pot or tank for pre-heating flexible glue equipped with heated rollers for applying a metered thickness of glue to cover and lining materials.
Glue pot
A simpled heated pot for melting flexible glue prior to applying it by hand using a brush.
HDPE
Abbreviation for high density polyethylene
High density polyethylene
This term is generally considered to include polyethylenes ranging in density from about .94 to .96 and over. Below .94 are polyethylenes known as medium density or low density.
Hinge reinforcement
A strip of canvas cloth or other strong material, such as Tyvek, which is used on the hinging areas on the inside of the binder or book between the backbone strip and the front and back covers. Use to relieve stress on the cover materials.
Lining
Refers to the material used to line the inside of the front and back covers that extends over the turned in portion of the cover material.
Modified polyethylene
High density polyethylene modified with additives to improve properties of the material, such as softening the plastic.
Non-woven
Refers to all cover materials substrates not made of woven yarn. Non-woven substrates are manufactured on paper making machines, as opposed to weaving machines. Non-wovens range from plain paper to latex-saturated paper reinforced with synthetic fibers for added strength.
Pleats
A term referring to the turning-in of excess material on round corner.
Poly binder
A single unit of polyethylene die cut and scored to form a looseleaf binder. The generic term for a poly binder is "cut flush ".
Polyolefin
A generic term that applies to a family of plastics that belong to the same general class of chemical compounds as paraffin wax. The principal members of this family are polyethylene and polypropylene. See Polyolefin Plastics for definitions of terms relating to the construction and manufacture of polyolefin plastics.
Polystyrene
A plastic material, which has outstanding electrical properties, good thermal and dimensional stability. However it is somewhat brittle and is often copolymerized or blended with other materials to obtain desired properties, such as adding rubber or butadiene to obtain higher impact resistance.
Ring protector
A "U" shaped piece of fiber, boxboard, lexide or other material placed between the rings and the inside cover of a binder to deter the possibility of the rings punching through a cut flush binder. Ring protectors are not required on poly binders.
Rivets
In loose leaf applications, a tubular fastener used for affixing the ring metal to the backbone or other desired position on the binder.
Round corner
Refers to the top and bottom corners on the fore edge of a binder where the corners have been rounded to eliminate a sharp, square corner. The cover material on a round corner turned edge binder is worked over the corners in plated form and pressed down tightly to provide a neat turn-in for the corner portions of the binder.
Sheet lifters
A special product designed to fit the ring mechanism of a binder to reduce sheet tear-out when opening and closing the binder. Sheet lifters can be used on all binders with a ring capacity of 1 1/2" and greater, and on all binders where the ring mechanism is mounted on the back cover.
Silk screening
A decorative technique where a direct impact stencil made out of cloth or wire mesh adhesive is used. In the early days of this technique, silk was used for the stencil. However, silk is rarely used today. A separate screen is required for each color desired.
Supported vinyl
A cloth or paper backed vinyl material offering heavy duty wearing qualities. Supported vinyl is often used as a cover material on turned edge binders.
Turned edge
Known alternately as "casebound" binding, a durable construction where the cover material is glued to binders board and the edges of the material are turned over the edges of the board. Produces an extremely durable, but expensive, finished product.
Woven
Refers to woven fabric substrate used to manufacture cover and lining materials. Woven substrates serve as a base to which coatings or laminations are applied to achieve desired aethetics. Normally woven with all cotton or combination poly/cotton yard for good glue adhesion.



