WO2015166422A1 - Method and machine to process a fabric - Google Patents

Abstract

A method for producing a fabric (T) from a roll having a surface trimming (P) is described. It comprises the steps of: piercing the fabric with needle-punching needles (22) in order to push fibers to its outside to form a fluff pad (P, P2) in relief. By the method, economic and ecologic, one gives the fabric a particular superficial trimming.

Description

METHOD AND MACHINE TO PROCESS A FABRIC

The invention relates to a method and corresponding machine to process a fabric, and the fabric thus obtained.

The denim fabric, here taken as an example, is the main material to produce very marketed garments, including blue jeans. Over the years this very common type of pants was developed with surface treatments or washes for crumpling it, aging it, decorating it, give an appearance of aging, or to adorn it with tears or paillettes. Abusing the fabric is a way to alter the appearance thereof and make it more attractive to the public, but each known additional processing is expensive, long and, ultimately, little able to innovate the fabric. Furthermore the known techniques use treatments with bleach or sand blasting, very harmful for the workers who perform it because they are in contact with the silica contained in the sand (causing silicosis).

To obviate at least one of these problems is the main object of the invention, which is defined in the appended claims, in which the dependent ones define advantageous variants.

It is therefore proposed a method for producing a fabric having a surface trimming or ornament or treatment , comprising the steps of:

piercing the fabric with needle-punching needles in order to push fibers to its outside to form a fluff pad in relief.

The method, and the machine that executes it, has the advantage of being able to replace wholly or partially the current systems and technologies used for the aging of the fabric with a new mechanical system, ecological and not dangerous to the health of workers.

The fluff can serve to create drawings or surface decorations, or for characterizing a fabric, or to alter the surface thereof by making it soft and/or cushioning.

Here are some preferred variants of the method:

- the needles are arranged in a row and/ or in groups separated from each other by gaps greater than the center-to-center distance between the needles; and/ or - the fabric comprises or consists of denim (fabric that has given best results, both regarding the surface and the abatement of costs and environmental damage); and/ or

- with a relative motion between the fabric and an area of perforation, in which the needles act, the fabric is perforated in continuous manner along a given path (which can foresee any direction, for greater freedom of design for the superficial trimming). In particular the area of perforation and the fabric are moved relatively transversely to the direction of said relative motion, in order to arrive to every point onto the surface with the piercing; and / or

- the movement transverse to said direction is an oscillating movement back and forth (to form curved patterns); and/ or

- the processed fabric is the superposition of a fabric and a layer of woven or non-woven fabric (to transfer the fibers of the added layer on the processed fabric, obtaining colorations and/ or variable features for the fluff); and/ or

- the fabric is processed on a roll or piece, to increase the hourly production. The roll or piece may have a minimum width of 80-90 cm, to exploit the commercial standard, or preferably of at least 120 cm to increase the hourly output.

It is also proposed a machine for producing a fabric, preferably from a roll of fabric, having on its surface a fluff pad in relief, comprising:

- one or more needle-carrying bars each equipped with a row (e.g. an aligned row or not) of needle-punching needles;

- two guides equipped with pass-through holes adapted to guide each needle and arranged at a certain distance from each other to create a gap in which to insert the fabric, preferably unwound from a roll;

- a first mechanism for moving with reciprocating motion the bar, so that the needles pierce the fabric inside the gap;

- a second mechanism for obtaining relative motion, between the fabric and the needle-carrying bar, perpendicular to the row of needles;

- a third mechanism for obtaining relative motion, between the fabric and the needle-carrying bar, parallel to the row of needles. The machine can allow the processing of the fabric throughout a whole fabric piece (roll) of any height, which can occur by moving the fabric in all directions, so as to obtain an infinite variety of paths (drawings). The intensity of the processing may vary, e.g. to change the relief in the finished fabric. Note that the machine (and method) does not require chemicals or hazards for the worker in charge, and there is also the possibility of advancing the fabric during the processing only when the needles are not penetrating the fabric (v. gap L, in the following).

We point out that this type of processing alters the appearance of the fabric only on a single desired face. Also, the machine, especially if denim is used, does not damage the fabric in a negative way (lacerations, weakenings and bad predisposition to subsequent washings), and keeps it wearable because it does not become wrinkled on one side, where it will contact the skin.

The machine (and method) is suitable, in general, to process any fabric, intended as a manufactured article constituted by a set of threads, made from textile fibers, interwoven among each other through the action of weaving according to a certain order, namely by twisting a thread with itself or by weaving together a given number of threads of given length arranged parallel to each other, or by interweaving a number of parallelly arranged yarns (warp or chain) with a continuous thread (weft) that passes through them transversely according to different ways (armor). There is no advantage in using a non-woven fabric. Advantageously, the fabric is processed from a roll, that is by holding it wrapped on a support such as the original one from the weaving. This not only increases productivity and convenience, but, being able to avoid all those aging treatments described in the introduction, costs are significantly reduced.

Here are some preferred variants for the machine:

- on the bar the needles are arranged in groups separated from each other by gaps greater than the center-to-center distance between the needles (this to create processed parts and intact parts on the fabric surface); and/ or

- the machine comprises two rollers for winding up the fabric that are placed on two opposite sides of the bar and are adapted to advance the fabric with respect to the gap (simple and controlled method for advancement). In particular the rollers can have a minimum width of 150 cm, for mounting thereon a piece of or roll of fabric; and / or

- the third mechanism is adapted to generate an oscillating movement back and forth between the fabric and the needle-carrying bar (to create processings with curves). However, the motion between the fabric and the needle-bar can be programmed or implemented not only as oscillating but also e.g. perpendicular or transverse, so that the machine is able to move the fabric in any desired direction.

In the machine and in the method the stem of the needles is not smooth but has hooks or steps or barbs able to drag the fabric fibers to the outside of it.

It is also proposed a fabric, produced by or with which to supply the method or machine, having a surface trimming comprising a fluff in relief formed by inner fibers brought to the outside. The fabric can comprise the overlap of a fabric and a layer of woven or non-woven fabric, e.g. the fabric comprises or consists of denim.

The advantages of the invention will be more apparent from the following description of a preferred embodiment of the machine, making reference to the attached drawing in which

Fig. 1 shows a schematic side view of the machine;

Fig. 2 shows a schematic top view of the machine;

Fig, 3 shows a cross-sectional view by the plane III-III of Fig. 2;

Fig. 4 shows a sectional view of a fabric which can be manufactured by the machine;

Fig. 5 shows a sectional view of a variant of fabric which can be manufactured by the machine.

In the figures, identical numbers indicate identical or conceptually similar parts, and the elements are described as in use.

10 designates a machine for processing a fabric, especially denim. A canvas of denim T is rolled on two rollers 46 which synchronously rotate (see arrows K) to advance it (see feed direction D) in the middle of a gap L present between two guides 30, 40 (e.g. two perforated bars) slightly spaced apart and supported by a frame 12. The width of the gap L, e.g. of about 2 mm, is adjustable to adapt the machine 10 to different thicknesses of the fabric T.

The guides 30, 40 are bored from side to side by pass-through holes 42 which serve to guide the punching-needles 22 arranged in series and parallel to each other on a needle-carrying bar 20. The needles 22 have on their stem, having an axis H (Fig. 6), means able to drag the fibers of the fabric T onto the outside of it.

The needle-bearing bar 20 is moved with reciprocating movement (arrow F) by a connecting rod 38 connected to a crank 36 fitted on the shaft 34 of a motor 28. Some guides (not shown) guide the motion of the needle- bearing bar 20, and the needles 22 periodically pass through the gap L perforating the fabric T in transit.

Fig. 4 shows the fabric T as it result when coming out of the gap L: it exhibits on the surface some relieves P in the form of barbs or lint or tufts, resulting from fibers pushed outside of the fabric by the needles 22.

The relieves P can form on the fabric T a pattern or design, or only an alteration of the surface to make it locally soft, absorbent or cushioning. Indeed the relieves P are normally curved and / or twisted fibers, protruding from the tissue T forming e.g. curls or balls, and can function as small springs or air chambers (fig. 4) .

The rollers 46 have axes of rotation 44 rotatable on a carriage or support 50 which is movable in a controlled manner. Through e.g. known drives in the machine 10 (not shown) one can move the carriage 50 transversely or orthogonally (see arrows W) to the direction D. Then, one can vary the path of the needles 22 on the fabric T to create thereon a row of pricks, and therefore of relieves P, which follows a curved line. The rate of displacement or the motion of the carriage 50 can be controlled as desired, e.g. through software that manages the drives.

To obtain designs or geometric patterns with the relieves P the needles 22 preferably are not mutually equidistant, but distributed in groups separated by empty spaces (without needles) wider than the center-to- center distance between the needles 22. The said distance can be constant or vary along the needle-carrier bar 20.

Note that it is possible to make machining operations by the whole bar, i.e. with the bar 20 having needles 22 distributed (e.g. uniformly) over its entire length. The machine 10 is adapted for processing a piece of fabric, e.g. as large as 1,5 m. However, the machine 10 is able to carry out the processing on all heights of available fabric without limits on the size of the fabric, nor minimum nor maximum.

As a speed range for the fabric supply experimentally a very good result on the fabric occurred with a minimum of 20 cm per minute to 5 meters per minute.

As a speed or frequency range for the needles 22's puncture, the machine 10 can go from a minimum of 100 pricks per minute to 800.

Usually the minimum length of a fabric piece is 3 meters, and the minimum width of a roller 46 can be determined according to the size of the roll (e.g. 5 cm to 3 m, in particular about 1,5 or 2 meters).

One can vary the surface effect P by superimposing a second textile layer T2 on the fabric T. The layer T2 can be a woven or a non-woven fabric. The manufacturing process allows the fibers to migrate from the layer T2 to the fabric T, bringing on the desired surface of the fabric T the or a pattern of the support fabric T2. For example, by using for the layer T2 a non-woven fabric or a fabric having a checkered pattern, the checkered pattern will appear in the fabric T.

The needles 22 pierce the layer T2 and the fabric T entering first in the layer T2, and bring on the surface of the fabric T also fibers of the layer T2 (indicated by P2). Therefore one can vary e.g. the consistency, or shape, or the color or the length of the relieves P, in order to increase the degrees of freedom in designing the appearance or function of the final product.

Note that the order of perforation of the tissue T is not binding. By using needles with barbs or hooks in the opposite direction or backwardly turned (compared to the previous case) one can create the relief P on the other face of the fabric T.

Claims

1. Method for producing a fabric (T) from a roll having a surface trimming (P), comprising the steps of:

piercing the fabric with needle-punching needles (22) in order to push fibers to its outside to form a fluff pad (P, P2) in relief.

2. Method according to claim 1, wherein the needles are arranged in a row and in groups separated from each other by gaps greater than the center-to-center distance (H) between the needles.

3. Method according to claim 1 or 2, wherein the fabric comprises denim.

4. Method according to any one of the preceding claims, wherein with a relative motion between the fabric and an area of perforation (L), in which the needles act, the fabric is perforated in continuous manner along a given path and the area of perforation and the fabric are moved relatively transversely to the direction of said relative motion.

5. Method according to claim 4, wherein the movement transverse to said direction is an oscillating movement back and forth.

6. Method according to any one of the preceding claims, wherein the processed fabric is the superposition of a fabric (T) and a layer of woven or non-woven fabric (T2).

7. Machine ( 10) for producing a fabric (T) having on its surface a fluff pad

(P, P2) in relief, comprising:

- one or more needle-carrying bars (20) each equipped with a row of needles (22);

- two guides (30, 40) equipped with pass-through holes (42) adapted to guide each needle and arranged at a certain from each other to create a gap

(L) in which to insert the fabric unwound from a roll;

- a first mechanism (28, 34, 36, 38) for moving with a reciprocating motion the bar, so that the needles pierce the fabric inside the gap;

- a second mechanism (46, 50) for obtaining relative motion between the fabric and the needle-carrying bar perpendicular to the row of needles;

- a third mechanism (46, 50) for obtaining relative motion between the fabric and the needle-carrying bar parallel to the row of needles.

8. Machine according to claim 1, wherein on the bar the needles are arranged in groups separated from each other by gaps greater than the center-to-center distance (H) between the needles.

9. Machine according to any one of the preceding claims, wherein the third mechanism is adapted to generate an oscillating movement back and forth between the fabric and the needle-carrying bar.

10. Fabric (T) having a trimming surface comprising a fluff pad (P, P2) formed by internal fibers brought on its outside.