(57) A method for the manufacture of rolls of pre-cut bags with punched handles, of the
type with "star" or "tomato" base, comprising the steps of: sliding movement of a
tubular film (10) in plastic material, formation of two opposite gussets (12, 14)
along side edges of said tubular film, single folding of said tubular film (10) gusseted
along a median longitudinal axis (17), insertion of a layer of Teflon (38) between
said gussets (12, 14) of the single-folded tubular film (10) with function of insulant
to prevent that the first gusset (12) and the second gusset (14) can weld one to the
other, formation of a transverse precutting line (23) apt to define a line of separation
between single bags (15) of said tubular film, formation of a transverse welding line
(16) at a base of the single bag (15) and of a transverse welding line (9) at handles
(11) of the adjacent bag (15), punching of the single-folded tubular film (10) to
define handles (11) of the bags (15), winding of said tubular film to form a roll
of bags (15) and wherein the steps of performance of the transverse pre-cut (23),
welding (16) of the base and welding (9) of the handles (11) of the single bags (15)
are carried out in a simultaneous way with the transverse welding (16) of the base
of a bag (15) performed downstream of the transverse welding (9) of the handles of
the successive and adjacent bag.
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