Modifiche

The cap is also often a characteristic element for the design and lines of a pen, and can be the subject of various decorations. Among these, a common element, widely used and still present on most of the caps, are the bands, or the various rings, whose original purpose was also strictly practical in nature. The edge of the cap is in fact one of the most stressed and subject to the risk of breaking a pen, and the original use of rings and metal bands (see patent {{Cite patent|US|662796}}) was precisely to reinforce the edge, and only later these have assumed the character of a decorative element.

The cap is also often a characteristic element for the design and lines of a pen, and can be the subject of various decorations. Among these, a common element, widely used and still present on most of the caps, are the bands, or the various rings, whose original purpose was also strictly practical in nature. The edge of the cap is in fact one of the most stressed and subject to the risk of breaking a pen, and the original use of rings and metal bands (see patent {{Cite patent|US|662796}}) was precisely to reinforce the edge, and only later these have assumed the character of a decorative element.

Historically, the first caps were made with a friction closure (those that are generically defined ''[[slip cap]]s''), with the cap that fits on the body. There are different variants of this type of choice, depending on the way in which the joint is made; the two main classes are the so-called ''[[cone cap]]'' (conical section cap) in which the interlocking surface is a truncated cone, and the so-called ''[[straight cap]]'' (cylindrical section cap) in which the interlocking surface is cylindrical, among the latter there are then the so-called ''[[tapered cap]]'' (conical or tapered cap) in vogue at the end of the 19th century.  

Historically, the first caps were made with a friction closure (those that are generically defined ''[[slip cap]]s''), with the cap that fits on the body. There are different variants of this type of choice, depending on the way in which the joint is made; the two main classes are the so-called ''[[cone cap]]'' (conical section cap) in which the interlocking surface is a truncated cone, and the so-called ''[[straight cap]]'' (cylindrical section cap) in which the interlocking surface is cylindrical, among the latter there are then the so-called ''[[tapered cap]]'' (conical or tapered cap) in vogue at the end of the 19th century.

The interlocking caps which suffer, especially in the ''conical'' version, from problems of wear on the surfaces with loss of tightness, have been followed, with a trend established since the beginning of the '900, by the caps with screw closure (''threaded cap''), which are still among the most common today. A return of the interlocking caps took place in the '40s with the introduction of metal caps closed with friction on special rings (trend introduced by the [[Parker 51]]).  

The interlocking caps which suffer, especially in the ''conical'' version, from problems of wear on the surfaces with loss of tightness, have been followed, with a trend established since the beginning of the '900, by the caps with screw closure (''threaded cap''), which are still among the most common today. A return of the interlocking caps took place in the '40s with the introduction of metal caps closed with friction on special rings (trend introduced by the [[Parker 51]]).