An automatic color mix dyeing process includes activating an automatic shaping device to shape an undyed object as a cylinder and tightening same; conveying the undyed object to a dyeing apparatus by means of spraying wherein the dyeing apparatus includes rows of spray devices, dye containers for containing dyes of different colors, each dye container being in fluid communication with the row of spray devices, a pump for moving the dyes in the dye containers to the rows of spray devices, and a control device for controlling the rows of spray devices to control a spray sequence, a spray time, and a spray quantity of dye; conveying the dyed object from the dyeing apparatus to a vapor device for color fixing wherein the dyed object is impregnated with hot vapor to obtain a finished object; cutting the tie ropes; and conveying, washing and drying the finished object.

Processes and apparatus are disclosed which substantially eliminate the formation of oxidized indigo dye before and during dye application onto a natural fiber yarn or fabric while allowing the leuco-indigo dye molecule to diffuse fully into the natural fibers of the yarn where it can fix to the fibers prior to oxidation (i.e., exposure of the leuco-dyed yarns to oxygen). Indigo dyed textile products (e.g., dyed cotton yarns that may be twill woven to form a denim fabric) exhibit exceptionally high colorfastness as determined by the AATCC Crock Test.

A stretching apparatus of fibre tows in a pressurized steam environment includes an elongated stretching chamber having a generally rectangular section of a low height, within which the tows are treated with saturated or overheated steam at high temperature and pressure and simultaneously undergo a mechanical stretching operation. The stretching chamber has a width sufficient to house multiple tows mutually flanked in a running plane and is formed within a stretching chest made of aluminum. The stretching chest is housed in a supporting structure, having a higher structural rigidity than the stretching chest, which includes a plurality of contact elements apt to determine a predefined position of the stretching chest with respect to a direction perpendicular to the tow running plane and to allow a limited mobility of the stretching chest in the other two mutually perpendicular directions which lie in the plane, length and width respectively.

A stretching apparatus of fibre tows in a pressurized steam environment includes an elongated stretching chamber having a generally rectangular section of a low height, within which the tows are treated with saturated or overheated steam at high temperature and pressure and simultaneously undergo a mechanical stretching operation. The stretching chamber has a width sufficient to house multiple tows mutually flanked in a running plane and is formed within a stretching chest made of aluminum. The stretching chest is housed in a supporting structure, having a higher structural rigidity than the stretching chest, which includes a plurality of contact elements apt to determine a predefined position of the stretching chest with respect to a direction perpendicular to the tow running plane and to allow a limited mobility of the stretching chest in the other two mutually perpendicular directions which lie in the plane, length and width respectively.