FR2837847A1 - COATED AND EXPANDED TEXTILE - Google Patents

Abstract

The present invention relates to a coated and expanded textile with patterns comprising at least: - a first expanded layer based on a rubbery material, comprising a first face, - a second layer containing a first face and a second face, the first face being applied to the first face of the first layer, the second layer consisting of a textile support and, where appropriate, having patterns printed on its second face, - a third so-called coating layer comprising a first face applied to the second face of the second layer, characterized in that the amount of said third layer and / or the texture of the textile support are adjusted so that their overall permeability is greater than 200 ml of air per minute evaluated for an area of 10 cm2 and a pressure difference of 5 millibars. It also relates to a process for its preparation. The invention applies more particularly to the manufacture of printed coated tablecloths.

Description

knots formed on several folds, in the dye bath (4).

  The present invention relates to expanded textiles and coated therewith.

  than a process for their preparation.

  The printed coated fabrics currently available, for example for the production of tablecloths or other articles of the tableware sector, generally have a coating layer based on PVC (polyvinyl chloride) and halogenated polymers in particular of fluoropolymers which are detrimental in terms of recyclability. Furthermore. these fabrics resist poorly food stains which remain more and more marked over time and become more and more difficult to remove. At the same time, they may lose their colors or their printing patterns, in particular as they are cleaned or under the effect of light, or even give rise to

yellowing.

  One of the objectives of the present invention is precisely to propose a new coated textile, usable in particular in the field of tableware, and not having the drawbacks mentioned above, that is to say

  which is anti-stain and not subject to yellowing.

  Another objective of the invention is to provide a coated textile combining

  with the aforementioned qualities, anti-slip, anti-shock and anti-

  heat. This second objective is for its part satisfied by the application on the back

  on the coated side of the printed textile, an expanded rubbery material.

  The difficulty encountered and overcome according to the present invention relates specifically to the calendering of a rubbery material on the back of a

  textile with the front side already coated.

  By definition, calendering means a technique for manufacturing sheets, plates or films comprising the rolling of a material

  thermoplastic between several cylinders constituting the grille.

  Generally in the rubber industry, this calendering operation is associated with a coating of the rubbery material on the surface of a porous support, for example a fabric. Following this calendering operation, the rubbery material is subjected to a viticanization or crosslinking operation during which the chemical transformation of the starting elastomeric mixture into a crosslinked network takes place. In the particular case of the preparation of so-called expanded rubber articles, at least one swelling agent is incorporated into the starting mixture. By decomposing under the action of heat, this agent generates gases, which gases develop bubbles in the elastomeric medium of low

  viscosity. This results in the expected expanded cell structure.

  In the case of the present invention, the waterproof nature of the coating proves to be incompatible with a consecutive calendering of a layer of elastomer (s) on the opposite face. The sealing of the coating constitutes an obstacle to the release

expansion gases.

  Unexpectedly, the inventors discovered that it was possible to

overcome this difficulty.

  More specifically, the present invention has for its first object a coated and expanded textile, comprising at least: - a first expanded layer based on a rubbery material, comprising a first face, - a second layer containing a first face and a second face , the first face being applied to the first face of the first layer, the second layer consisting of a textile support and having, where appropriate, patterns printed on its second face, - a third so-called coating layer comprising a first face applied to the second face of the second layer characterized in that the amount of said third layer eVou the texture of the textile support are adjusted so that their overall permeability is greater than 200 ml of air per minute evaluated for a

  surface of 10 cm2 and a pressure difference of 5 millibars.

  The textile forming the support may comprise or consist of a fabric, a nonwoven or a mesh, the fabric and the nonwoven being preferred. It can be either natural, artificial or synthetic textile. It may be an ecru or white textile of a dyed woven fabric, a dyed-in-the-mass textile, a dyed woven textile or a printed textile. According to a preferred variant of the invention, this textile support is dyed or has a printed face. The choice of the texture of the textile support is generally made so that with a coating of the order of 25 g / m2 the air permeability of the support in a coated form is sufficient to be compatible with the production of calendering, crosslinking and expansion of the

  rubbery material on the back.

  In this case, the textile support generally has a texture of 24 × 24 threads per cm for a title of 34 × 34 metric numbers. However, it is also possible to use a textile support with a chain texture of 24 to 40 threads per cm, i.e. 28 to 50 metric numbers eVou

  a weft of 16 to 30 threads per cm, or 28 to 50 metric numbers.

  The composition of the coating layer according to the invention is compatible with an application on a textile support, either by calendering or extrusion, or

by loom to be coated with tunnel.

  Preferably, the first coating layer is applied correctly

  about 10 to 25g / m2 on the surface of the first face of the second layer.

  Coatings derived from at least one acrylic resin, polyurethane or one of their mixtures prove to be particularly advantageous in the

part of the present invention.

  This coating layer may also contain various additives, in particular to improve eVou to modify the mechanical properties of the final printed coated textile, its UV resistance. It may in particular be plasticizer (s), agent (s) for protection against according to a preferred variant of the invention, the layer weight ratio

  coating / textile support is between 5 and 15 and preferably 7 and 12.

  As emerges from the definition of the claimed textured support, it is imperative that the thickness of this coating layer eVou the texture of the textile support are adjusted to obtain the permeability required according to the invention. In this case, too much crossing of the coating layer causes a sealing of the textile support and causing poor expansion of the layer of rubber material. Conversely, a localized crossing of the coating layer results in insufficient adhesion of the

rubbery material.

  These two difficulties are precisely overcome by adjusting the amount of said overlay eVou the texture of the textile support so as to give them an overall permeability greater than 200 ml of air per minute.

  for an area of 10 cm2 and a pressure difference of 5 millibars.

  For the purposes of the present invention, the term “rubbery material” is intended to denote a material having as main component at least

  minus a natural or synthetic rubber or a mixture thereof.

  According to a preferred variant of the invention, the rubbery or even elastomeric components are chosen so as to lead to a starting rubbery mixture having a Mooney index of between 40 and 80

  estimated at a temperature of around 50 C.

  This Mooney consistometric index actually corresponds to a torque value. The torque to be applied is determined under determined conditions for rotating a metal disc in a sealed cylindrical chamber filled with rubber material. The resistance opposed by the rubber to this rotation, expressed in arbitrary units, is the

  Mooney consistency of the test tube.

  The Mooney consistometric index is therefore the value of the torque exerted on the rotor, expressed in Mooney units, indicated by the device after a warm-up time of 1 minute followed by a rotor rotation time generally from 4 to 8 minutes. In the case of the present invention, this index is measured for a temperature of around 50 ° C. of the rotor. For more details, refer to the notice published by the French standard NFT43005

as of December 1991.

  The rubber compounds suitable for the invention can be chosen from natural rubbers, synthetic rubbers based on styrene, butodiene and their mixtures. In addition to its rubbery components, the initial mixture intended to constitute the expanded layer comprises at least one crosslinking system.

and an expansion system.

  According to a particular variant of the invention, these systems are chosen so as to be active at the same temperature, between 150 C and

210 C.

  As regards more particularly the crosslinking system, it comprises at least one crosslinking agent, also called primary accelerator. This crosslinking agent preferably belongs to the family of thiazoles,

quinones or quinones-dioximes.

  It is preferably present in an amount of 0.5 to 8% by weight relative to

  the mass of the rubbery material to be transformed.

  This primary accelerator is preferably associated with a so-called agent

secondary accelerator.

  This secondary accelerator preferably belongs to the family of metallic or non-metallic dithiocarbamates, metallic xanthates or

  non-metallic or to the thiezole family.

  This secondary accelerator is generally present at a rate of 0.2 to 2% by weight and more preferably from 0.2 to 1.5% relative to the weight of the

rubbery material.

  By way of illustration of the crosslinking systems capable of being implemented in the claimed process, mention may be made of the following primary and secondary accelerator pairs: Primary acceleratorsFamily of thiazoles; Secondary accelerators - Dithiocarbamate family; Primary accelerators - Thiazole family; Secondary accelerators - Xanthat family;

  Primary accelerators - Family of quinones or quinones-

  dioxime; Secondary accelerators - Thiazole family.

  The crosslinking system may be present in the rubber mixture to be transformed at a rate of approximately 4 to 10% by weight relative to

  the weight of the rubbery material.

  As regards the expansion system, it comprises at least one blowing agent. This blowing agent may belong to the family of

  azodicarbonamides or the sulfohydrezide family.

  The decomposition temperature of blowing agents related to azodicarbonamides varies between 160 and 210 C, as for blowing agents belonging to the family of sulfohydrazides, their temperature

  decomposition is greater than 105 C.

  These blowing agents are generally associated within the system

  expansion at least one expansion regulator.

  By way of representative of the expansion regulators suitable for the present invention, one can more particularly name urea and its derivatives, zinc-based compounds of the zinc oxide, zinc stearate type, as well as the

amino compounds.

  Generally the expansion system is incorporated at a rate of approximately 2

  10% by weight of the rubber material to be treated.

  In addition to these essential components, the rubber material to be transformed can also incorporate other conventional additives such as anti-oxidation agents intended to prevent premature aging of the rubber mixture. It is also possible to incorporate charges of varying proportions. It can be reinforcing fillers such as kaolin or carbonate of magnesia or even carbon black. It can also be calcium carbonate or silicate or even ultra-fine silica. The fillers are in fact products which can be incorporated into said mixture without greatly lowering its mechanical qualities. By way of illustration of other fillers, mention may be made of chalk, kaolin, baryte sulfate, kieselguhr,

talc and lithopone.

  It can also be incorporated into the rubber mixture one or more plasticizers. Suitable in particular as plasticizers, petroleum-based oils such as naphthenic, aromatic and aliphatic compounds, plasticizers of the phthalate family such as dioctyphthalate (DOP) and flame retardant plasticizers of the type

chlorinated phosphates and paraffins.

  In addition to these additives, the rubber mixture may include pigments for coloring the final material, odorants to combat the odor of Vuicanized rubber, flame retardants for fire protection, hardeners to prevent deformation during certain types of manufacturing, retarders to sometimes moderate the too rapid action of accelerators, peptizers to soften rubber, etc. The selection of these additives as well as the adjustment of their respective proportions in the rubber mixture to be processed is well

  heard from the know-how of a person skilled in the art.

  The coated and expanded textile can also be protected on the coated side. This protection can be ensured by the application of a varnish, in particular of acrylic type, of a silicone-based resin or a fluorinated treatment. Depending on the desired effect, the protective varnish can be colorless or colored

  but transparent to reveal the printed motif (s).

  The coated and expanded textile according to the invention has in particular great flexibility as well as good resistance to aging, to

  weather, ultraviolet radiation and food stains.

  As soon as "anti-stain" additives of known type can be introduced by

  example in the final protective varnish to increase the anti-

  textile stains end u it, for example vis-à-vis food stains.

  The invention also provides a process for the preparation of the coated textile printed above, characterized in that: - there is a textile forming a support comprising a first face and a second face and if necessary having patterns printed on its second side. - a coating material is deposited on the second face of the textile support, the coating material is crosslinked, - a rubbery material is deposited on the first face of the textile support, - one proceeds successively or if mu ltanéme nt at the crosslinking and expansion of the rubbery material, - a protective treatment of the coated face is optionally carried out

textiles.

  The deposits of the materials in front respectively constituted the coating and the expanded on either side of the textile support are generally produced by

calendering or coating.

  Following this calendering step, each material is then subjected to at least one crosslinking operation in order to transform the

  starting elastomeric mixture in a crosslinked network.

  In the case of the rubbery material, this crosslinking operation is

  combined with an expansion operation.

  In general, the methods for manufacturing conventional expanded rubber materials integrate the two crosslinking and expansion operations concomitantly. Conventionally, the elastomeric strip or sheet is recovered at the end of the calendering operation to then be placed in an enclosure heated to temperature

  suitable for carrying out the crosslinking operation.

  According to a preferred variant of the invention, the crosslinking and expansion stages are carried out simultaneously, at short notice and in continuity with the calendering operation, this makes it possible to optimize the mechanical qualities mainly in terms of elasticity, rubbery cellular material

expanded thus obtained.

  More preferably, these two stages of crosslinking and of expansion are carried out continuously by horizontal displacement of the material which has just been calendered, in an enclosure, preferably a tunnel brought to the appropriate temperature for the concomitant execution of the crosslinking and of the expansion, not in an oven and on a vertical plane in accordance

to conventional processes.

  Cross-linking and expansion reactions are generally

  performed at atmospheric pressure.

  In a variant of the invention, the expandable rubber mixture may, following the calendering operation and beforehand

  during the crosslinking and expansion operation, undergo a graining operation.

  This operation aims to apply on the exposed face of the calendered rubbery cellular material unevenness forming protrusions and hollows whose all surfaces have a certain grain and are more or less regular and not smooth. The appearance of the product is considerably

improved.

  In this particular case, after calendering the rubbery material, there is printed in relief, on the exposed face of the layer obtained by calendering, that is to say not linked to the textile support, any pattern which

  will be kept at the level of the finished article.

  The invention also relates to articles containing a coated textile as mentioned above. It applies more particularly to the manufacture of coated tablecloths or other articles intended for tableware or to articles

  intended for interior decoration, in particular wall textiles.

  The invention will now be illustrated with the aid of an example and a

  figure which should not be considered as limiting.

FIGURE:

  FIG. 1 is a schematic representation of a coated and expanded textile according to the invention: 1) designates the expanded layer 2) represents the textile support and,

3) shows the coating layer.

EXAMPLE 1:

  The different production phases of a printed coated tablecloth are as follows: 1) Use of a printed or plain cotton fabric with a weight of 120 g / m2 to

the support layer.

  2) Coating with a doctor blade on the support of an acrylic resin weighing

  g / m2. Drying and crosslinking at 1 60 C.

  Formula: - Suspension acrylic resin (60% ES) 50-75 - Suspension aliphatic polyurethane resin (40% ES) 25-50 - Thickener 2-6 Fluoropolymer 5-15 - Crosslinking agent (etherified derivative of melasmine formaldehyde) 1- 6 - Antifoam 0.5-2

  3) Calendering on the back of the support coated with a rubbery material.

  Composition of the rubber mixture used: by weight * Natural rubber type SMR CV 100 * Pepticant (dibenzyl amidodiphenyl disulfide) 0.1 - 0.2 * Dummy5 -1 5 * Chalk20 - 60 * Kaolin10 - 30 * Plasticizer naphthenic30 -50 * Paraffin1 - 4 * ZnO5-10 * Stearic acid1-3 * Protective agents1-3 * Sulfur1 - 2.5 * Zinc diethyl dithiocarbamate0.3 -1.4 * Benzothiezyl disulfide1 - 2.5 * Sulfohydrazide blowing agent4 - 10 * Urea4 -10 The strip thus obtained is directed to an expansion and crosslinking tunnel brought to a temperature of 180 C. The strip passes continuously through this enclosure so that its residence time does not exceed 5 minutes. The tunnel exit is cooled and the expanded coated fabric is recovered. According to an alternative embodiment, the strip is grained

  before entering the expansion tunnel.

  4) Coating on the coated side with an acrylic type varnish containing additives to make it stain-resistant. Deposit of 20 g / m2 of a 15% solution

  dry extract. Drying and crosslinking at 160 C.

Claims (13)

  1. Coated and expanded textile, comprising at least: - a first expanded layer based on a rubbery material, comprising a first side, - a second layer containing a first side and a second side, the first side being applied to the first face of the first layer, the second layer consisting of a textile support and, where appropriate, having patterns printed on its second face, - a third so-called coating layer comprising a first face applied to the second face of the second layer characterized in that the quantity of said third layer eVou the texture of the textile support are adjusted so that their overall permeability is greater than 200 ml of air per minute evaluated for a   surface of 10 cm2 and a pressure difference of 5 millibars.   2. coated and expanded textile according to claim 1, characterized in that the first coating layer is applied at a rate of approximately 10 to   25g / m2 on the surface of the first face of the second layer.   3. coated and expanded textile according to claim 1 or 2 characterized in that the weight ratio coating layer / textile support is included   between 5 and 15 and preferably 7 and 12.   4. Textile end u it and expanded according to one of res ications 1 to 3 characterized in that the coating layer is based on at least one resin   acrylic, polyurethane or a mixture thereof.   5. Coated and expanded textile according to any one of the claims   1 to 4, characterized in that the textile support comprises or consists of a fabric, nonwoven or mesh.   6. Coated and expanded textile according to any one of the claims   1 to 5, characterized in that the textile support has a texture of 24 × 24 threads   per cm for a title of 34x34 metric numbers.   7. Coated and expanded textile according to any one of the claims   1 to 6, characterized in that the textile support is dyed or has a printed face. 8. Textile end u it and expanded according to any one of resells ications 1 to 7 characterized in that the components of the rubbery material of the first layer are chosen so as to lead to a starting rubbery mixture having a MOONEY index included between 40 and   estimated at a temperature of around 50 C.   9. Process for the preparation of a coated and expanded textile such as   defined according to any one of claims 1 to 8, characterized in that:   - there is a textile forming a support comprising a first face and a second face and, where appropriate, having patterns printed on its second face, - a coating material is deposited on the second face of the textile support, - the crosslinking of the coating material, - a rubbery material is deposited on the first face of the textile support, - the crosslinking and the expansion of the rubbery material are carried out successively or simultaneously, and - a treatment for protecting the coated side textiles.   10. Method according to claim 9, characterized in that the layer   coating is as defined in any one of claims 2 to   4. 11. PmcAdA seen vendahon 9 or 1Q, c6hsA in that   Refile support is of fabric, non-woven or mallle type.   12. Aside Mona un Amid endue expanse seen une _ 1 8 ^ 9A 11.   13. Acme salon endi1ion 12, sounding like a tablecloth.   14. Article salon la récicadon 12, conslsisnt en murale textile