Marking installation for containers made of thermoplastic material obtained by a stretch-blow moulding process

A marking installation for containers made of thermoplastic material obtained by a stretch-blow moulding process, said container comprising at least a body, a shoulder extending from said body at an upper end thereof, a neck extending from the shoulder and a wall, said wall comprising at least one information region, wherein said installation comprises at least:

• two conveyors configured to convey said containers along two distinct conveying paths on two distinct packaging lines from an inlet to an outlet of each conveyor;
• and
• a plurality of laser marking devices configured to apply information in said at least one information region, each marking device being positioned between the two conveyors and being configured to apply information alternately in the information region of a container of a first conveyor then in the information region of a container of a second conveyor.