Ligne
Ligne is a French word meaning line. It was in use prior to the French adaptation of the metric system in the late 1700s, and is still used by French and Swiss wristwatch makers to measure the size of a watch movement. (For example, Girard-Perregaux will introduced a new 12 ligne chronograph movement.) In this usage there are 12 ligne to one French inch (pouce). The standardized conversion for a ligne is 2.2558291 mm (1 mm = 0.443296 ligne), and it is abbreviated with the letter L.

In the eighteenth century the term ligne came into use among German button makers, where is was used to measure the diameter of buttons. The consensus definition was that a ligne was the measurement of a round wick, folded flat. In this sense it measures 1/40th of an inch. 

Ligne : A button's ligne, refers to a button's size. The word ligneis a French word that became the standard reference used by German button manufacturers in the early eighteenth century. Ligne is the internationally recognized standard. Consensus at the time was that a "ligne" measured the inside diameter of a "round wick folded flat." One inch is equal to 40 English ligne, 11 French ligne,and 25.5 mm. 

LINGE               =       MILLIMETERS         =              INCHES  

14

9.2

.362

16

10.5

.413

18

11.6

.457

20

12.5

.492

21

13.5

.531

22

14.2

.559

23

14.8

.583

24

15.0

.590

27

16.8

.661

28

17.8

.701

30

19.0

.748

32

20.5

.807

34

21.5

.846

36

22.9

.902

40

25.5

1.00

Scale of Button Sizes
Buttons are measured by the English standard of 40 lignes
per inch. Therefore, a 30 ligne button is 3/4" diameter, a 45 ligne button is 1-1/8" diameter, and so on. The diagram shows the size of a button shell before covering.

 

 

Buttons Specifications
Material Used: ABS plated, Alloy Metal, Aluminum, Brass, Cast, Fabric Covered, Buffalo Horn, Cow Horn, Ox Horn, Real Horn, Animal Bone, Coconut Shell, Wood, Imitation Pearl Polyester, Imitation Shell Polyester, Melamine, Metals, Nylon, Natural Pearl, Polyester Chalk,Polymat Polyester, Rubber, Natural Shell, Urea, and Natural Wood. 
Application: General-Women's, Men's and Children's Wear, Toys, and Consumer Goods.

Sizes Available (English Ligne-approx. mm)

12 Ligne-6 mm
13 Ligne-7 mm
14 Ligne-8 mm
15 Ligne-9 mm
16 Ligne-9.5 mm
17 Ligne-10.5 mm
18 Ligne-11 mm
19 Ligne-12.5 mm

20 Ligne-13 mm
21 Ligne-13.5 mm
24 Ligne-16 mm
28 Ligne-18 mm
30 Ligne-19 mm
32 Ligne-20 mm
34 Ligne-21 mm
36 Ligne-22 mm

40 Ligne-25.5 mm
44 Ligne-28 mm
45 Ligne-29 mm
48 Ligne-30.5 mm
50 Ligne-32 mm
60 Ligne-38 mm
64 Ligne-40.5 mm
65 Ligne-41 mm
Attachments/Styles Colors Available

2 Hole
4 Hole
Toggle
Shank

 

White
Black
Dyed to Match
Dull
Matte
Polished
Gold
Silver
Antiqued Metals

Note on button sizes

Rather than in inches, dealers in commercial buttons distinguish according to series of measures called ligne. For reference, the table below indicates the ligne measurement and corresponding ligne sizes:

1/3"

14 ligne

3/8"

16 ligne

7/16"

18 ligne

1/2"

20 ligne

9/16"

22 ligne

5/8"

24 ligne

3/4"

30 ligne

7/8"

36 ligne

1 1/8"

45 ligne

1 3/8"

55 ligne

1 3/4"

70 ligne