Optical fiber unit and machining method for optical fiber unit

An optical fiber unit, comprising:

• a first optical fiber ribbon that intermittently connects a first plurality of optical fibers;
• a second optical fiber ribbon that intermittently connects a second plurality of optical fibers;
• and
• interlayer connection parts that intermittently connect the first optical fiber ribbon and the second optical fiber ribbon in a length direction while the first optical fiber ribbon and the second optical fiber ribbon are layered and arranged,
• wherein
• the first optical fiber ribbon and the second optical fiber ribbon are layered and arranged such that optical fibers having a same fiber number of the first optical fiber ribbon and the second optical fiber ribbon are aligned in an up-down direction perpendicular to the length direction, and
• the interlayer connection parts are disposed on a layer of a connection agent constituting in-layer connection parts that intermittently connect the optical fibers of the first optical fiber ribbon or the second optical fiber ribbon.