EP0121748B1 - Apparatus and method for producing decorative synthetic coatings - Google Patents

Abstract

A process and apparatus for manufacturing synthetic decorative coverings is presented in which at least one powder (generally a polymeric resin) is selectively deposited, in accordance with a pattern or decoration, onto a base material. The power deposition is carried out under gravity without contact between the means of applying the powder and the base. At least one of the deposited powders contains particles which are fusible at a temperature below the distortion temperature of the base and which is compatible with the base material. At least one thermal treatment is then carried out at a temperature below the distortion temperature of the base so as to fix the decorative pattern produced by deposited powders. The apparatus for applying the powders consists of a continuous screen printing frame, in particular, a screen printing roller which is fed by a device providing uniform distribution of the powder into a hopper located inside the roller. The hopper has two longitudinal blades which are adjustably separated and are in contact with the inner surface of the screen.

Description

The present invention relates to a method of manufacturing synthetic decorative coatings, an installation for this purpose and extends to the products obtained.

The term “synthetic coatings” means coatings produced from organic elements which may involve in their formulation products of a mineral (for example asbestos or glass veil) or vegetable (jute) nature.

The production of synthetic decorative coating products, in particular of floors and walls, based on synthetic materials, essentially based on PVC has experienced a significant development in recent decades.

Generally, these products are constituted by a support made of various materials, for example jute fibers, asbestos, non-woven glass fibers, synthetic foam, etc. On this support is applied a sheet or a layer PVC which receives, on the side of use, the desired decoration, itself generally protected by a transparent film.

Many variants have been applied for the realization of this decor. All the techniques used are however related to printing techniques and which use more or less viscous liquid preparations. A particular technique, also derived from printing techniques, consists in the localized application of plastisol pads by screen printing.

The printing preparations used therefore have in common the fact that a liquid which may be water or a solvent is used for the preparation of a more or less pasty printing ink.

Generally, to carry out the entire decoration, it is necessary to provide for several successive applications by printing different elements of the decoration, which makes it necessary to dry before each printing run and we finish off with a transparent protective element.

These techniques give only mediocre results, in particular when it is a question of imitating enamels, in particular floor tiles or wall tiles. Various improvements, in particular the use of foaming agents with simultaneous and localized application of retarding agents or accelerating foaming agents have been proposed to achieve localized expansion (FR-A-1 411 338). Even in this case, we note that, if the geometric aspect of the tiling can be reproduced fairly faithfully, the surface state specific to enameled products is only poorly reproduced and does not have the aspect of depth specific to these products. .

From documents DE-A-2 260 788 and FR-A-2 263 893, artisanal processes are known for producing patterns by depositing fusible substances on a support of metal, glass or ceramic or a other material which is stable at the temperature of the subsequent heat treatment. These methods are intended for the discontinuous production of colored patterns in the form of travel souvenirs or the like.

Document FR-A-7 437 741 discloses a process for printing textile surfaces, in particular long-pile materials, in which dye preparations are applied in powder form on the surface to be printed, according to a decoration. corresponding; the dye is fixed and the particles which are possibly not fixed are eliminated. This document relates only to textile surfaces and is in no way intended to provide a coating imitating the effects of enamels generally obtained on ceramic materials. On the contrary, the printing process described in document FR-A-7 437 741 aims to deposit a dye on a pile textile by a technique of depositing dye powders in the interstitial space of the fibers. This technique is essentially dependent on the support and its state of preparation. The final decorative effect sought is limited to adding color to the fibers without seeking a volumetric effect.

Document CH-A-595 145 describes the deposition of powders through a screen printing frame necessarily in contact with the support by the use of a magnetic doctor blade. Such a technique does not allow variable volume deposition of the powders.

The document GB-A-1 087 560 describes a method and a device of the type set out in the preamble to claims 1 for method and 17 for installation.

This device comprises a perforated cylinder supplied with powder by an internal hopper and constituted by two elements provided with perforations, such as rotary concentric cylinders, designed so as to bring, as a result of the relative movement of the elements, the perforations in correspondence and free from in this way the powder according to a determined sequence on a strip of material passing under the installation. This installation operates without contact of the powder dispensing device with the strip of material receiving the powder deposit.

By its very design, however, it does not make it possible to apply a deposit of material in a relatively complicated pattern such as the deposits necessary for the production of the usual decorations for floor and wall coverings. As indicated in the document, the device is designed for deposits of glue dots.

It should also be noted that the apparatus described in document GB-A-1 087 560 does not make it possible to obtain a decorative pattern of desired shape and volume (relief) because of its construction comprising two cylinders rubbing the one on the other which allow a passage of powders during the matching of perforations with which they are provided. The volume of powder deposited is in fact limited by the flow of powder which can pass through two openings which are only in correspondence for a period of time which depends on the relative speed of rotation of the two cylindrical walls.

Furthermore, those skilled in the art cannot withdraw from the patent raised any teaching allowing two or more successive deposits to be made in synchronism to achieve a desired decoration. The rigidity of the apparatus claimed in the cited patent constitutes an insurmountable barrier for the deposit of precise and variable decorations according to the requirements of a floor or wall covering having to present in addition to a fine and precise polychrome decoration, an effect in relief in accordance with the decorative patterns, such as, for example, a relief tiling pattern and a connection joint, all of this using in particular PVC powders, which must undergo gelation.

Finally, from documents FR-A-2 291 868 and FR-A-2 210 148, a method is known in which a fixation of particles, fibrils or powders is effected for the same purpose. electrostatic field, on a support coated with an adhesive product.

These various techniques are not satisfactorily applicable to the production of flexible multi-layer floor and wall coverings, which require significant resistance to delamination, as well as to other constraints.

Applicants, on the other hand, seek to move away from printing techniques to create a new method of applying powders and having a volume effect opening wide fields of application and ensuring perfect adhesion of the decorative element for the intended use, namely, floor and wall coverings.

The present invention therefore aims to remedy the drawbacks of the known method and device described in document GB-A-1 087 560 and to provide a method and a device making it possible to produce decorative coatings with an appearance mainly similar to ceramic and enamel coatings.

The object of the present invention is achieved by a process for manufacturing synthetic decorative coatings, in which a powder is deposited locally, on a support, according to a pattern or decoration, by gravity to the continuous serigraphic frame, without there being any has contact between the means of application of the powder and the support, characterized in that at least two successive deposits of powders can be deposited locally which can be superimposed without disturbing the design of the previous deposit, without intermediate fixing, by means of at least two screen printing frames placed one behind the other, at least one of the deposited powders containing fusible particles at a temperature below the deformation temperature of the support, and of a nature compatible with that of the support or at least in the vicinity of said temperature and in that at least one heat treatment is carried out at a temperature below the deformation temperature of the support, in order to fix the decoration obtained by depositing e powders.

Advantageously, a rotary screen printing frame will be used.

The decoration will preferably be fixed at least partially by co-fusing the motif with the final support.

By co-fusion is meant a homogeneous nesting of the decoration with the support during the heat treatment sufficient to prevent delamination.

Surprisingly, it appeared that this technique makes it possible to obtain flexible and rollable products, of remarkable aesthetic appearance, having good mechanical and wear properties, suitable for floor and wall coverings. This effect is moreover obtained without resorting to the usual techniques in the treatment of plastics by doubling which generally involve a combination of a mechanical pressure effect with the application of a thermal effect, in particular by calendering.

It is particularly advantageous that during said heat treatment, said powder penetrates at least partially inside said support.

According to an operating variant of the invention, the deposition of said powder can be carried out on a temporary intermediate support on which a heat treatment is carried out and in that the deposition thus carried out is transferred to the aforementioned final compatible support.

Other characteristics of the present invention will appear from the description which follows.

The method makes it possible in particular to imitate the colored effects which are obtained by ceramists by the use of powders forming glazes, enamels as well as mixing and spreading effects, in a similar manner to ceramic products and enameled products. The choice of deposition techniques and powders makes it possible to obtain decorations of all kinds, such as abstract patterns or patterns commonly used in this field.

According to the present invention, the technique of deposition without contact between the means of application of the powder and the support has many advantages.

Thus, the process of the invention can be used for any type of support compatible with the powder used or treated beforehand to make it compatible with this powder, such as those mentioned in the introduction to the present invention, or even supports whose the surface is not smooth or has a significant relief, as a result of a previous deposit, for example, which may have been carried out optionally according to a conventional process. However, it is also possible to use a rigid support, organic or inorganic, compatible with the nature of the powder used. It will also be noted that, as a result of the choice of support and of the powder applied, the products of the invention can be flexible and, while having an appearance similar to ceramics, can be produced continuously and by rolling them up. The support used may or may not be armed, it being understood, however, that the support must have sufficient stability, among other dimensions, at the temperature of the heat treatment of the powders used.

Another advantage of the "contactless" technique is that we superimpose different layers of powders without having to at least partially fix the previous layer (s). This makes it possible to obtain particular effects due to the interpenetration or overlapping of the strata one in the other. This advantage however also takes on an important economic dimension since it is possible to eliminate the treatments (generally thermal) of fixing between several deposits and to carry out only one final heat treatment. As a result, energy is saved by using only one oven which is continuously maintained at temperature, and by avoiding heating and cooling the product during manufacture several times in succession. In order to obtain certain specific effects, it may however be advantageous to provide intermediate fasteners between two applications of powders.

According to a first variant of the present invention, the means for applying the powders consists of at least two continuous serigraphic frames placed one behind the other, each comprising meshes distributed according to a desired decoration, through which the powders are distributed over the support.

Each screen printing frame can take the form of a rotating cylinder, driven by a circumferential speed synchronized with the speed of travel of the support, and supplied with powder, uniformly over the entire length, by an internal hopper of which two lips (scrapes) rub on the inner face of said cylinder. Adjusting the spacing of these lips makes it possible to adjust the flow rate of powder as a function of the speed of rotation thereof, the size and shape of the meshes and the fluidity of the powder. In this case as a result of the absence of contact and of gravity deposition, the dosage of the powders therefore does not depend on the volume released by a mesh, as in the uses of the screen printing frame in contact for printing.

Consequently, it is possible by a judicious choice of the mesh dimensions according to the generator of the screen printing cylinder to punctually dose the quantity of powder deposited.

The local superposition of one or more layers of powders makes it possible to obtain relief effects but also particular effects in the intensity, the hue, the depth, the shine and / or the iridescence of the colors, for example.

To make decorations similar to enamels, one can for example use, in the case where the support is essentially made of PVC containing the usual ingredients, in particular stabilizers and plasticizers, to powders constituted by a polyester resin, of polyamide, polyolefin, polyvinyl, polyurethane, polyacrylate or acetate or a compatible mixture of these resins. The powder chosen according to the support, will generally be colored and will therefore contain mineral or organic pigments or dyes. When using organic pigments or dyes, however, use those which are stable at the temperatures to which they will be subjected.

In addition, the particular decorative effects can be obtained, by the technique of the invention, by using powders of different properties. These different properties can be the melting point, hot viscosity, wettability or other physical (diffusion and / or solubility) or chemical characteristics.

Advantageously, particular decorative effects can be obtained by including in the powders materials which create heterogeneity in the coating, in particular ground mineral materials, for example, ground ground powder, textile fibers, etc.

The technique of the invention is compatible with the use of known techniques for the preparation, production and finishing of floor or wall coverings, in particular for the production of decor. This is how the decoration produced by the technique of the invention can be perfected by another decoration and that the finished product can receive a wear layer, transparent or colored, etc. The known techniques for producing reliefs by embossing or differential foam expansion can also be combined with the technique of the invention.

It should be noted that, in particular, the technique of the invention does not exclude the complementary use of known techniques of decoration by screen printing using a plastisol.

Due to the absence of contact between the support and the powder applicator, the support can be previously coated with liquid or paste, partially or completely, in order to obtain decorative effects.

When the decorative coating obtained does not have the desired surface properties (wear, abrasion, puncture, scratches), these can be obtained by depositing an adequate coating.

When the decoration has been applied to the support, the heat treatment at least partially causes the powder to melt, while of course being careful not to displace this decoration. Heating by infrared radiation gives good results. However, it is also possible to use other advantageous heating techniques such as support heating, etc.

By a choice of powders used, one can obtain particular matte effects. Thus, for example, a fusible powder can be smoothed during fusion and provide a shiny surface state while a low-melt powder can be deposited at the joints of the tiles, for example to obtain a matte joint imitating the cement. ; however, said "joint" must be fixed during the heat treatment by chemical reaction or light fusion or by fusion of a component part of the powder deposited at the location of the joints and / or by co-fusion with the support in order to present a sufficient strength.

Similarly, a swelling agent can also be incorporated into the powder in order to obtain a foamable deposit and locally accentuated relief effects.

Some effects can be obtained by subjecting the support with its deposits before thermal fixation to controlled disturbances of mechanical, pneumatic or electrical origin (vibrations, air blowing or electric field).

The present invention also relates to a manufacturing installation for implementing the above method, defined in claim 17.

The present invention offers many possibilities and is certainly not limited to the examples described above or in the following description, but covers all variants within the scope of the invention.

• - la figure 1 représente une vue schématique d'une installation de fabrication destinée à la mise en oeuvre du procédé de l'invention:
• - la figure 2 représente une vue en coupe partielle d'un cylindre sérigraphique travaillant hors contact;
• - la figure 3 est une vue en coupe transversale du cylindre de la figure 2, et
• - la figure 4 est une représentation schématique d'une coupe dans un revêtement mural obtenu suivant le procedé de l'invention.

The present invention will be described in more detail, with reference to the following examples and to the accompanying drawings in which:

• FIG. 1 represents a schematic view of a manufacturing installation intended for the implementation of the method of the invention:
• - Figure 2 shows a partial sectional view of a screen printing cylinder working out of contact;
• FIG. 3 is a cross-sectional view of the cylinder of FIG. 2, and
• - Figure 4 is a schematic representation of a section in a wall covering obtained according to the process of the invention.

With reference to FIG. 1, a manufacturing installation intended for the implementation of the method of the invention comprises, by way of example, an unwinding device, a powder application means 2, an oven intended for heat treatment 3, a cooling zone 4 and a winding and cutting device 5.

According to the present invention, the powder application means 2 comprises at least two cylinders of the type shown in FIGS. 2 and 3, the wall of which is constituted by a serial frame, a hopper inside each cylinder 10 being equipped of two longitudinal lips 15, 16 spaced apart by an adjustable distance and scraping the inner surface of each frame 10.

The oven 3 intended for heat treatment and causing at a temperature below the deformation temperature of the support, that is to say at a temperature of the order of 200 ° C., a certain co-fusion of the fusible components of the powder and of the support, thus creating the adhesion of the deposits to the support, a smoothing of the surface (gloss) or at least the bond between the grains of powder, is advantageously a source of heat by infrared radiation. The oven 3 can however also heat the support 6 in order to improve the fixing of the powders. An oven can also be provided by hot air or by any other heating means.

The cooling zone 4 can consist of a simple passage in the open air of the support coated with powders fixed during the treatment in the oven. Cooling can be accelerated and improved by a stream of cooled air, water exchangers or any other suitable means.

The cutting and winding device is known per se and does not require any additional description.

As can easily be seen, the production chain described in this application example comprises four successive powder application cylinders without intermediate fixing. The method is however not limited to this type of application and it is advantageous to provide a greater number of cylinders as well as an intermediate fixing by a slight heating of the support, for example.

In the given application case, the four cylinders each rotate at the same circumferential speed, this preferably having the same value as the linear speed of travel of the support, but it is also possible to work at different speeds if one wishes to obtain particular decorative effects.

The manufacturing installation described can obviously also be fully or partially integrated into a conventional production chain intended for the manufacture of floor or wall coverings.

Figures 2 and 3 show a cylinder for the application of powders, commonly called a rotating frame. It consists of a screen-mesh screen 10, fed by a uniform distribution device, for example, a screw 12 rotating in a supply duct 13 which distributes the powder uniformly in a hopper 14 inside the cylinder. The two longitudinal lips 15 and 16 of this hopper separated by a variable distance, to regulate the flow of powder which passes through the frame 10 as a function of the speed of rotation thereof, the fluidity of the powder and of the size of the meshes in order to constitute localized deposits 17 on the support 20.

The adjustment of the spacing of the lips can be carried out by means of a screw 18.

According to one embodiment of the invention, the sieve comprises meshes of different shapes and sizes and / or densities depending on the desired pattern. In this way, as a result of the absence of contact and of the gravity deposit, the flow rate of the powder will be locally more or less important depending on the dimensions of the meshes and therefore the differences in color intensity and / or real relief of the decor could be obtained as well.

The manufacturing installation described is intended for a continuous process. However, in the case of a batch process, one can provide a screen printing frame (frame) plane on which slides a hopper whose lips (scrapes) are spaced apart by an adjustable distance.

Example 1

The example of manufacturing a wall covering according to the method of the invention is described in support of FIG. 4.

The covering represents, in section, a drawing of tiling. The decoration consists of four successive deposits of powders, obtained on a continuous production line according to FIG. 1.

The support 41 may be cardboard coated with PVC, a thermosetting bonded nonwoven coated with PVC, a glass mat impregnated with PVC and other supports commonly used for this application and compatible with the powder used.

On prépare les poudres en préparant en premier lieu une poudre de base, de préférence non colorée, dans un mélangeur rapide du type PAPENMEIER comprenant une cuve chauffante et une cuve de refroidissement.In the example, a support has been chosen composed of a glass veil weighing approximately 50 g / m ² , bonded by a thermosetting resin and coated with a plastisol of formula:

The powders are prepared by first preparing a base powder, preferably not colored, in a rapid mixer of the PAPENMEIER type comprising a heating tank and a cooling tank.

• - le fond de pavé rouge 42, la composition suivante:
  
• - le joint de carrelage mat 43, la composition:
  
• - le vernis opalescent satiné 44, la composition:
  
• - le motif décor brillant orange 45, la composition:
  
  
  En vue du dépôt, les quatres cylindres d'application sont alimentés par l'intermédiaire de leur trémie intérieure par les quatres poudres obtenues précédemment.

The composition of the base powder is as follows:

• - the background of red block 42, the following composition:
  
• - the matt tile joint 43, the composition:
  
• - the opalescent satin varnish 44, the composition:
  
• - the bright orange decor pattern 45, the composition:
  
  
  For the purpose of deposition, the four application cylinders are supplied via their interior hopper with the four powders obtained previously.

The quantity to be deposited is adjusted by opening the lips of the internal hopper so as to obtain the following average thicknesses (after heat treatment):

The total weight of the deposit is approximately 500 +/- 30 g / m2.

The total weight of the finished article is 1000 +/- 50 g / m ² .

The heat treatment which consists of cooking, is advantageously carried out in a single operation in an I.R. oven set to quickly obtain a temperature of the order of 190 to 210 ° C. The heat treatment should last about 45 seconds for the thickness and weight of the above mentioned item.

Out of the oven, the item is quickly cooled and rolled up when the temperature is at most 50 ° C.

In the case of a floor covering the formulas and the procedure are essentially identical; it should however be added that the essential difference lies in the support 41 which is more suitable for use on the ground.

Example 2

In this example, we have chosen supports composed from a thin metal sheet. This type of support can be used to provide the finished product with better insulation properties.

The sheet chosen is in this example an electrolytic copper sheet of 35 microns (± 280 g / m ² ) from Yates Industries which has undergone on one of its faces a treatment increasing the porosity.

The base powder and the colors are prepared as in Example 1. The decoration is deposited as in Example 1. The heat treatment is slightly longer than in Example 1.

The adhesion of the decoration on the support depends on the porosity of the support (Table 1). It is zero on the smooth side. It can be improved by first coating an element compatible with the support and the PVC powder. As an example, some adhesion values are given in table 1.

Example 3

In this example, the supports are chosen from the range of paper supports generally used for floor and wall coverings.

The tests focused on supports coated or not with a PVC plastisol. The formulation of PVC plastisol is identical to that given in Example 1. The deposited weight is 150 grs / m ² and the coating is pregelified at 150 ° C ± 15 ° C.

The base powder and the colors are prepared as in Example 1. The decoration is deposited in the same way. The heat treatment is identical. Only the coated supports have no influence on the coloring of the decoration.

Example 4

In this example, the decoration is prepared and deposited as in the previous examples but on an incompatible support (silicone paper, for example).

After heat treatment and cooling, the decoration is detached from this intermediate support and deposited on a stable and compatible support. The assembly then undergoes a heat treatment in an IR oven set to quickly obtain a temperature of the order of 190 to 210 ° C. At the exit of the oven, the article is cooled quickly and rolled up when the temperature is below 50 ° C. The decor does not show any deformation, thus showing the absence of tension in the decor sheet.

As a variant, the support and the decor can be assembled on a so-called "combining" machine, the heating cylinder of which would be at a temperature between 120 and 150 ° C.

• Le procédé procure une meilleure stabilité dimensionnelle du produit obtenu étant donné qu'il n'y a pas de contact, donc pas de pression et, par conséquent, moins de traction sur le support qui n'est plus soumis qu'à une tension d'entraînement assez faible.

The advantages of the process of the invention can be summarized as follows:

• The method provides better dimensional stability of the product obtained since there is no contact, therefore no pressure and, consequently, less traction on the support which is no longer subjected to a tension d rather weak training.

• Le dépôt de poudre peut quant à lui être effectué même sur un support liquide.
• Le procédé de l'invention fournit un gain d'énergie important, étant donné que l'on peut obtenir un effet d'émail à une température (200°C) beaucoup plus basse que celle qui est couramment utilisée pour des émaux.
• En outre, il est possible d'effectuer, dans une même chaîne de fabrication, des dépôts successifs sans prégélification ou fixation thermique intermédiaire.
• Par suite de l'absence de contact, on peut provoquer une différence de vitesse entre la rotation des cylindres d'application des poudres et le défilement du support afin de créer des effets spéciaux de déformation des décors sans pour autant présenter des décalages comme dans le cas d'impressions superposées.

We can get rid of the surface condition of the support, in fact, printing on a non-planar or pasty surface is practically impossible.

• Powder deposition can be carried out even on a liquid support.
• The method of the invention provides a significant energy saving, since an enamel effect can be obtained at a temperature (200 ° C.) much lower than that which is commonly used for enamels.
• In addition, it is possible to carry out, in the same production line, successive deposits without pre-gelation or intermediate thermal fixing.
• Due to the absence of contact, it is possible to cause a speed difference between the rotation of the powder application cylinders and the scrolling of the support in order to create special effects of deformation of the decorations without however exhibiting offsets as in the overlapping prints.

• Le procédé de l'invention permet également d'obtenir des carrelages chaque fois légèrement différents, sans présenter la répétition obligatoirement obtenue par impression.
• Les effets obtenus ne sont pas limités à l'imitation de céramiques, mais l'invention permet aussi de réaliser des effets d'imitation de textiles, notamment de toiles ou de fils, ou de créer des effets anti-dérapants, etc...
• En plus des revêtements de sols et de murs, on peut appliquer les produits à la décoration au sens large, avec ou sans effet technique complémentaire, et ce en intérieur comme en extérieur.

There is great flexibility in terms of the decorative effects sought; it is possible to mix several powders with different properties, shade, melting point, coefficient of expansion, etc., so as to obtain different degrees of mattness, inclusions, cracks and / or craterings caused for example by internal tensions or chemical additives (like imitating terracotta, etc ...).

• The method of the invention also makes it possible to obtain tiling each time slightly different, without having the repetition necessarily obtained by printing.
• The effects obtained are not limited to the imitation of ceramics, but the invention also makes it possible to achieve imitation effects of textiles, in particular fabrics or threads, or to create anti-slip effects, etc.
• In addition to floor and wall coverings, products can be applied to decoration in the broad sense, with or without additional technical effect, both indoors and outdoors.

Claims (20)

1. Process for manufacturing synthetic decorative coverings, in which a powder is deposited locally, on a base (41) according to a pattern or decoration, under gravity with a continuous screen printing frame in the absence of contact between the means for applying the powder (2) and the base (41), characterized in that at least two successive deposits of powders (44, 43, 45) which may be superimposed without disrupting the design of the previous deposit, are deposited locally, without an intermediate fixing, by means of at least two screen printing frames (10) placed one behind the other, at least one of the deposited powders containing particles which are fusible at a temperature below the distortion temperature of the base (41) and which are of a nature compatible with that of the base (41) or at least close to the said temperature and in that at least one thermal treatment (3, 4) is carried out at a temperature below the distortion temperature of the base (41), with a view to fixing the decoration produced by depositing powders.

2. Process according to Claim 1, characterized in that the said frame is a rotary frame (10).

3. Process according to Claim 1 or 2, characterized in that, during the said thermal treatment (3, 4), the said powder (42, 43) penetrates at least partially inside the said base (41).

4. Process according to Claim 1, characterized in that the deposition of the said powder is carried out on a provisional intermediate base on which a said thermal treatment (3, 4) is carried out.

5. Process according to any one of Claims 1 to 4, characterized in that the said thermal treatment (3, 4) produces at least partially a co-fusion of the pattern with the final base (41).

6. Process according to any one of the preceding claims, characterized in that the said final base (41) is a base which is flexible, and capable of being reeled and unreeled.

7. Process according to any one of the preceding claims, characterized by the successive deposition of powders (42, 43, 44, 45) with different physicochemical properties such as hue, melting point, wettability, and coefficient of thermal expansion.

8. Process according to any one of the preceding claims, characterized in that several registered layers of powders (42, 43; 44; 45) are deposited at least locally and then a single thermal treatment is carried out to fix these.

9. Process according to any one of the preceding claims, characterized in that the means for applying powders consists of of at least two continuous screen printing frames (10) placed one behind the other, each comprising meshes distributed according to a desired decoration, over which a powder hopper (14) moves whose two lips (15, 16) which have an adjustable opening scrape the surface of the said frame (10).

10. Process according to any one of the preceding claims, characterized in that the means for applying the powders consists of at least two continuous screen printing rolls (10) placed one behind the other and fed by a device for uniform distribution of the powder into a hopper (14) inside each roll, whose two longitudinal lips (15,16) are separated by an adjustable distance and are in contact with the inner surface of the screen (10).

11. Process according to any one of the preceding claims, characterized in that the powders employed consist of a thermoplastic such as a resin of a polyester, polyamide, polyolefin, polyvinyl, polyurethane, polyacrylate, acetate or compatible mixtures of these resins, if appropriate coloured by organic or inorganic pigments.

12. Process according to any one of the preceding claims, characterized in that included in the powders are materials producing a heterogeneity, such as ground inorganic materials, textile fibres or others.

13. Process according to any one of the preceding claims, characterized in that the thermal fixing treatment consists of a controlled co-fusion of the fusible components of the powders (42, 43) with at least a part of the base (41).

14. Process according to any one of the preceding claims, characterized in that the thermal treatment or treatments are carried out by supplying external heat, particularly by infrared radiation and/or by hot air.

15. Process according to any one of the preceding claims, characterized in that the thermal treatment or treatments are carried out by heating the base.

16. Process according to any one of the preceding claims, characterized in that the base with its deposits is subjected, before thermal fixing, to controlled disturbances of a mechanical, pneumatic, electrical or other origin.

17. Manufacturing equipment for making use of the process according to any one of the preceding claims, comprising at least an unreeling device (1), a means for applying the powders (2), an oven (3) for the thermal treatment, a cooling zone (4) and a device for winding and cutting (5), the means for applying the powders (2) comprising a perforated roll fed with powder by an internal hopper, characterized in that the means for applying powders (2) consists of at least two rolls whose wall consists of a screen printing frame (10), the hopper (14) inside each roll (10) being equipped with two longitudinal lips (15, 16) separated by an adjustable distance and scraping the inner surface of each frame (10).

18. Manufacturing equipment according to Claim 17, characterized in that each frame is fed by means of a screw (12) rotating in a feed duct (13) which distributes the powder uniformly in the hopper (14).

19. Manufacturing equipment according to Claim 17 or 18, characterized in that the means for applying powder consists of rolls rotating at the same circumferential speed, the latter having the same value as the linear speed of passage of the base.

20. Manufacturing equipment according to Claim 17 or 18, characterized in that the means for applying powder consists of rolls rotating at a circumferential speed which is different to the speed of passage of the base.

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