Brother TD-4100N - Manual (Page 25)

ESC G Apply double-strike printing
[ASCII] ESC G
[Decimal] 27 71
[Hexadecimal] 1B 47
[Parameters] None
[Description]
・ Prints subsequent print data bold.
・ This command is valid anywhere in a text line.
ESC H Cancel double-strike printing
[ASCII] ESC H
[Decimal] 27 72
[Hexadecimal] 1B 48
[Parameters] None
[Description]
・ Cancels bold style.
・ This command is valid anywhere in a text line.
[Example]
Code
ABC ESC G DEF ESC H GHI FF
Print result
ABCDEFGHI
25