Mainly used for notebooks, desk calendars and wall calendars, drawing albums, cookbooks, training manuals, form books, drawing boards. Wire-O double-loop wire has a better texture than plastic coils, mostly used for high-end notebooks.
Divided into three types: plastic coil binding, wire-o double-loop binding, single spiral coil binding.
Principle: holes are punched on the side of the book, and plastic/metal coils are threaded through the holes to string the pages together.
Features: can fold 360°, pages can flip to the back of the book; can also open 180° completely flat;
Is a loose-leaf structure, theoretically pages can be added or removed (plastic coils can be opened; double-loop wire is difficult to open);
There is a row of round/square holes on the side, occupying the side margin; hole punching positions must be reserved during design;
The spine is a coil, cannot print large-area text.
Page count upper limit: depends on coil diameter, from dozens of pages thin to about 300 pages thick;
Punching: round holes / square holes;
Advantages: excellent page-turning experience, suitable for flat writing;
Disadvantages: side punching takes up space; metal coils have risk of collision deformation; not suitable for long-term collection.
