Method for preparing a paper web with a composite paper mesh for use to produce bags, and composite paper mesh

A method for preparing a paper band with a composite paper mesh, for use in the manufacture of bags, the paper band of those which are used for the manufacture of bags intended for the packaging and transport of products of any kind and products belonging to the horticultural sector, which paper band includes openings or windows that can be covered or closed by means of a mesh portion bonded to the same paper band by means of a glue stretch that surrounds perimetrically the aforementioned opening or window the method of preparing a composite mesh that can be divided into such portions for application to the windows of the paper band, comprises:

• dividing the sheet of a paper reel into a variable number of continuous longitudinal strips of paper of a width in accordance with the desired final strength and with the aid of automated cutting means;
• dividing the sheet of a paper reel into transversal fragments that make up cross pieces, with a width in accordance with the desired final strength and with the aid of automated cutting means;
• applying the aforementioned cross pieces on two longitudinal strips, parallel and separated from each other by the length of the cross pieces, occupying positions spaced along such longitudinal strips separated consecutively by distance in accordance with the dimensions of the windows to be covered, and performing, with the aid of automated means, the bonding between the cross pieces and the longitudinal strips by gluing the respective end portions of said cross pieces superimposed on both longitudinal strips, so as to obtain a grid structure that makes up a support base;
• applying on said support base grid structure a mesh of paper yarn obtained continuously from a reel, of a width equivalent to that of said support base grid structure, and bonding said mesh of paper yarn to the grid structure by applying a glue, with the aid of automated means, to obtain a composite mesh;
• dividing said composite mesh into portions on the basis of the positions occupied by the respective cross pieces, and
• finally, applying the portions of composite mesh to each respective one of the windows formed in the band, for the covering thereof, the bonding between the portions of composite mesh and the band being performed by virtue of a glue stretch that surrounds perimetrically each of said openings or windows.