FI114440B - Thermo-adhesive lining - comprising textile support coated dot-wise with crosslinkable polymer sub-layer which is thermo-fusible - Google Patents

Abstract

Prodn. of a thermoadhesive lining comprises:- (a) adhering a textile support (2) on a conveyor belt (100); (b) depositing dotwise a sublayer (4) of polymers on the textile support by means of a first rotating drum (112); (c) depositing a top layer (5) of thermoadhesive polymers having a dot distribution identical to that of the sublayer by means of a second rotating drum (113); (d) separating the coated textile support (2,4,5) from the conveyor belt and (e) passing the textile support through a continuous drying oven and then cooling. Also claimed is the obtd. lining.

Description

»114440

METHOD FOR MAKING THERMOADHESIVE FABRIC COVER AND THERMOADHESIVE FABRIC COVER

The invention relates to a method for producing a thermoadhesive fabric cover as defined in the preamble of claim 1 and to a thermoadhesive fabric covering as defined in the preamble of claim 5.

It is generally known to produce thermoadhesive fabric coatings consisting of a textile 10 support overlaid with a spot-spread thermoadhesive polymer layer.

These fabric coatings are intended to laminate other textiles, e.g. fabrics, to form a complex whose physical properties, strength, conformation, flexibility, feel, volume, etc., can be controlled.

These properties of the complex depend on the nature of the fabric, the nature of the textile support of the fabric covering, and the nature of the thermoadhesive layer and its configurable nature.

After manufacture, the thermoadhesive fabric cover must be capable of being stored at ambient temperatures. Thus, it is necessary that the different layers of the product normally stored on the roll do not stick together. The thermoadhesive fabric cover must not be '·' · sticky.

The thermoadhesive fabric cover is then later laminated to the fabrics to obtain the desired complex.

*: 30 Such lamination is often performed by means of a weight which is carried out at a temperature of 100-180 ° C, by weight. in a few decibars and a few bars ···. at intervals, in relatively short periods of time; * ίο - 30 s.

• · 114440 2 During this step, the adhesive property of the thermo-adhesive polymers of the fabric coating must be restored at least in part.

During this operation, it is necessary to avoid the penetration or back penetration of these thermoadhesive materials through the fabric, i. through fabric support for textile upholstery.

Such penetration would adversely affect the aesthetic appearance of the product, rendering the fabric wrapping unusable, or at least could cause undesirable properties that are contrary to the desired properties of the complex.

Publication, TEINTEX, Vol. 37, No. 11, 1972, Paris (pp. 601-606), describes products and methods used in thermoadhesion, as well as materials for their use.

During the first use of thermoadhesive fabric coatings, a penetration phenomenon was observed, followed by numerous attempts to avoid the phenomenon.

In particular, attempts have been made to solve the problem by placing a plurality of successive layers of polymer having different properties on the textile support.

U.S. Patent No. 2,631,947 describes termoadhe. 25 padded cloth covers for patching, consisting of a textile support and two; ·. of a continuous adhesive layer having viscosities. are different. The layer in contact with the support has a melting point higher than the surface layer. This facilitates the adhesion of the fabric to the fabric being repaired, improves its durability during successive washings and prevents penetration.

GB-A-1 133 331 and GB-A-1 360 496 * describe a fusible fabric cover for the garment industry consisting of a textile covered with a discontinuous adhesive layer formed from a first thermo - · 114440 3 of plastic material, then each dot site is coated with a second polymeric material, which may be heat-crosslinkable or have a higher melting point than the first material.

5 FR 2 177 038 now discloses fabric fabricating by sequentially applying two layers of adhesive to a support. The first layer is made by coating a 10 viscous dispersion with high viscosity and / or high melting point polymers using a raster coating.

The second layer is formed by scattering a powder of thermoadhesive polymers having a lower viscosity and / or melting point than the polymers of the first layer.

The formation of a second layer by scattering over the first viscous layer does not produce a very regular second layer. The points formed by this second layer generally extend beyond the points formed by the first layer, resulting in penetration during lamination.

According to FR 2 318 914 and FR 2 346 058, it has been proposed that the textile support be simultaneously coated with two layers of polymer in the form of a dry powder using a gravure printing. '* · 25 blades. In this case, the lower layer also consists of polymers. having a viscosity and / or melting point higher than / •> pi than that of the second layer polymers.

Coatings made by the dry process: gravure cylinder suffer from a lack of mechanical cohesion 30 over these two polymer layers. The interface between these two layers forms a weak spot, and protective clothing made of this type of fabric cover * ... * does not stand up well to maintenance treatments.

....: 35 DE 2 461 845.9 discloses a simultaneous coating which takes place in a screen printing process. sweat, two viscous dispersion layers, containing polymers of different viscosity and / or melting point. The delivery of the two pastes is carried out in the same frame with two separate scrapers placed in parallel.

5 Such a method is extremely difficult, if not impossible, to implement. Experience has shown that it is impossible to fill the cylindrical engraving holes without all or part of the dispersion being supported by the textile. The coating thus forms a permeation of a mixture of these two dispersions on the textile support, whereby a high quality fabric covering cannot be achieved.

Finally, according to FR 2 576 191, which is assigned to the applicant of the present application, a sequential coating of 15 layers of different viscosity and / or melting point is disclosed, whereby the two layers are provided on both sides with a textile support.

It is an object of the present invention to provide a thermoadhesive fabric covering and a process for its manufacture which is easily industrially applicable and which provides high quality products.

The invention thus provides a process for producing a thermoadhesive fabric covering, wherein a textile-based, thermally adherent, thermoplastic is applied to the textile support. 25 Coating of Moadhesive Polymers.

With respect to the features characteristic of the method according to the invention, reference is made to claim 1.

· According to the invention:; - the textile support is glued to the conveyor belt; ! | 30 having good dimensional stability; applying a lower layer of spot-dispersible thermostable polymers to the textile support by a first rotary frame device; the lower layer polymers, after being applied to the textile 35, are at least dried and / or partially cross-linked; 114440 - an upper layer of thermoadhesive polymers which are uniformly punctured with respect to the lower layer is superimposed on the former by another rotary frame device; the perforating dimension of the second rotary frame device being equal to or less than the perforation dimension of the first frame device; controlling the speed of rotation of the second rotary frame device, its mounting angle and the speed of the conveyor belt by the speed of rotation of the first rotary frame device such that the peripheral speeds of said frame devices correspond to the rate of propagation of the conveyor belt; - removing the coated textile support from the conveyor belt 15; - the coated textile support is passed through a continuous drying furnace and then cooled.

The lower layer may contain at least one substance capable of reacting with the upper layer of thermoadhesive polymers, and the lower layer may be dried and / or partially cross-linked after being applied to the textile support prior to application of the upper layer.

The invention further provides a thermoadhesive fabric coating, which is characterized by the following:.

Preferably, the upper layer thermoadhesive • · *. ; The set properties change progressively from the contact area of the lower 3 0 layers upwards.

According to a preferred embodiment, the lower layer contains polymers belonging to the group consisting of crosslinkable silicones, polyurethane compounds, crosslinkable polyurethanes 35 and polyacrylates.

t ·

The upper layer preferably contains polymers. which belong to the group consisting of polyamides, copolyamides, polyesters, copolyesters, polyurethanes and polyethylenes.

In another preferred embodiment, the upper layer comprises reactive function polymers belonging to the group consisting of styrene-ethyl acrylate copolymers, melamines, aziridines, isocyanates, unsaturated polyesters, and epoxy resins.

The invention will be described in more detail with reference to the accompanying drawings, in which Figure 1 schematically shows a fabric cover according to the invention, Figure 2 schematically shows a first embodiment of the apparatus according to the invention, Figure 3 schematically shows a second embodiment of the apparatus .

The fabric cover 1 consists of a textile support 2 and 20 heat-adhesive coating points 3.

Textile support 2 is known per se. It is of the same type as textiles conventionally used in fabric coverings.

It can be woven or knitted or non-woven textile. These textiles are generally: converted and then subjected to finishing treatments before being used as a coating support.

Cotton or wool fibers can be used.

I I

However, polyester-> t / 30 texture textiles or non-woven sandwiches, which avoid the risk of linting, have the best results. More generally, fabrics made using a continuous or textured type of synthetic continuous filament yarns are particularly suitable.

35 Textile support 2 is attached in the first * ·. step to conveyor belt 100.

Preferably, the closed-loop conveyor belt 100 then passes over the conveyor rollers 101-104.

The conveyor belt 100 is preferably made of polyester-5 terry textiles coated with a layer or coating of crosslinked silicone polymers. It is important that this belt has good dimensional stability, especially in the longitudinal direction.

In fact, as seen below, it is subjected to 10 major tensile forces and temperature differences, which must not cause significant displacements of the textile support 2 attached thereto. It can also be a fabric made of glass fibers or aramid fibers, respectively coated with a layer or coating of cross-linked silicone poly-polymers.

The conveyor rolls 101-104 arranged in connection with the guide means (not shown) ensure that the belt runs perpendicular to the axes 20 of the frame members 112 and 113 and ensure that the position of the belt 100 is stable in a direction parallel to these axes. A roller known as a deformation roller can be used to facilitate this fit.

The container 105 contains an aqueous adhesive. 25 106 and scraper 107 ensure that the aqueous · * · .; the adhesive continuous coating layer 108 is applied to the conveyor belt 100.

, ·>. The aqueous adhesive 106 used is based on 1 '/. starch, dextrin, sodium carboxymethylcellulose, sodium carboxyethylcellulose, high t '*' * * high molecular weight (greater than 4,000), but polyethylene glycol or polyvinylpyrrolidone ·. / mea) at ambient temperature for the conveyor belt 100 35 under escort conditions.

Preferably, a composition which:. contains a uniform distribution of water mass and adhesive mass, and the amount of material to be supplied is of the order of 1-4 g / m 2.

The textile support is fed from the roll 109. The web / counter roll arrangement 110, 111 is disposed on each side of the conveyor belt 100 and the textile support 2 and ensures that they are in contact with each other and thereby secure the textile support to the conveyor belt 100.

The points of distribution of the points 4, 5 of the polymers 10 are successively applied to the textile support 2 attached to the conveyor belt 100 by rotating frame devices 112 and 113. The axes of these devices are parallel to one another and perpendicular to the conveyor belt 100 shown above.

These rotary frame devices, known per se, interact with doctor scrapers 114 and 115, on the one hand, and counter rollers 116, 117, for the purpose of spot-forming coatings.

Such rotary frame devices allow the use of wet coating methods, whereby an aqueous dispersion of very finely divided polymers is applied to the textile support by a hollow scraper device arranged inside a rotating frame device having a thin \. 25 perforated wall. The scraper allows the paste · to pass through the cylinder openings.

Thanks to the invention, means have been found on the basis of the inventive tufts that allow each of the upper-layer coating points 5 to be placed on the lower layer in successive positioning of two dot-distributed topsheets. over the coating point 4.

• <· To achieve this coincidence, the speed of rotation of the second rotary frame device 113, its mounting angles 3 and the propagation speed of the support belt 100 are monitored. preferably a first rotary frame device. 112 speed. This control is accomplished by the t * «» 11 44 114440 9 optoelectronic device shown schematically in Figure 4. Each cylinder is provided with a reference mark 118 and the like, respectively. 119, read by optical sensors 120, 121. The electronic information produced by these sensors 5 is further provided to processing unit 122 which monitors the rotation speed of the rotary frame devices 112 and 113 and the propagation speed of the conveyor belt 100 by means of motors 123, 124, 125.

This control is performed such that the peripheral speeds of the rotary frame members 112 and 113 correspond to the propagation speed of the conveyor belt 100 and thus the textile support 2. Thus, each coating point 5 of the upper layer is superimposed on the coating layer 4 of the lower layer.

15 Thanks to the opto-electronic system, monitoring can be performed in good conditions. The system may also be electromechanical, electronic or electromagnetic.

After first placing the lower layer of polymers 20 and then the upper layer of thermoadhesive polymers 5 on the textile support 2, the conveyor belt 100 / coated textile support 2,3, 4 arrangement is passed through a continuous drying furnace 126.

The purpose of this oven is to provide water and thermoadhe. '. 25 winged polymers are paste-forming, coated / ;; evaporation of the dispersion to be delivered.

φ »: \> t The furnace temperature is preferably near the poly-, ··· melting point of the mers, and the furnace may be a hot air oven, a microwave oven or a radiation oven, and may be !, * 30 ventilated.

Good results are achieved with drying times of the order of about 10 s.

After passing through the drying furnace 126, the coated textile support 2, 4, 5 is removed from the conveyor belt 100 and then cooled. After that, it • *> t # t; stored on a roll 127.

i · I · · 114440 10

When conveyor belt 100 forms a closed loop, it is washed with a bristle brush 12 8 immersed in wash water 129.

The rotary frame devices 112 and 113 include, as described above, perforations which, during the formation of the lower and upper coating layers, produce coating points 4 and 5, respectively. 5.

The dimensions of these perforations determine the dimensions of the coating points to be formed.

Generally, the distance between the points on the conveyor belt 100 with respect to the rotating frame members 112 and 113 is sufficiently short so that the lower layer has not yet dried when applied to the upper layer.

15 In contrast, in some applications, the lower layer must dry before placing the upper layer. In this case, a second furnace 150 is arranged between the rotary frame devices 112 and 113.

It is now the first time to describe the manufacture of a fabric overlay using polymer paste. In order to increase the volume of the coating points 3, and in particular to increase the volume of the upper layer 5 of the polymers, the rotary frame device 113 preferably feeds a polymer-containing foam. This foam is formed in a mixer fed with polymers, \; paste dispersion and added surfactant, · substance and injected air.

* ..> t The foam thus formed is placed on a rotating I »'.'h rack device. As the coating passes the furnace 126 * * | Through the foam, the air bubbles contained in the foam are broken and the air is removed as the product disperses at the same time, allowing the thermoadhesive polymers to settle.

i · ·

Precisely engraved printing frames are important for the quality of the end result. It is important that the second rotary frame device 113 is a complete copy of the first frame * device 112. That is, I · # * · so that the center of the opening corresponding to each coating point 4, 5 corresponds to each other even if the dimensions of each coating point 5 of the second rotary frame device 113 are as described above. smaller than the coating points 4 of the first rotary frame device.

5 Various methods can be used to make printing frame devices: - they can be made using letterpress printing. The matrix for the manufacture of racking devices is embossed with a small diameter embossing roll 10 provided with embossing. This matrix is then placed in an electrolyte solution to enable the manufacture of racking devices.

- the second method is computerized embossing. The coordinate of this patterning is used to monitor a numerically controlled laser device which pre-patterns electrolytic deposition areas surrounding the through holes in the frames into a cross-linked resin coated roller sleeve.

These methods allow structures to be obtained with an accuracy of the order of 10 microns for hole diameters of the order of 500 to 1000 microns.

The thickness of the lower layer 4 of the thermoadhesive fabric covering is preferably small. This thickness, '·', which is determined by the thickness of the first rotary frame device 112: ', is preferably 0.05 to 0.20 mm. The lower layer is provided in the form of a single aqueous phase dispersion consisting of a water / thickener / polymer mixture.

The polymers are preferably crosslinkable. The best results have been obtained for crosslinking silicones, fluorinated polyethylenes, crosslinking polyurethane,. dispersions based on Danish and polyacrylates.

35 The important function of the lower layer is to prevent *! '·. the penetration of the upper layer through the textile support 2 while maintaining the physical textile properties of this textile support 2.

Preferably, the upper coating layer 5 has a thickness of 0.4 to 0.8 mm.

The aqueous dispersion used to form the topcoat layer preferably consists of the following composition (parts by weight): - 40-60% water - 25-35% thermoadhesive polymers 10-1-2% ammonium polyacrylate thickener 25-35% dispersion.

The thermoadhesive polymer is polyamide, co-polyamide, polyester, copolyester, polyurethane, polyethylene, etc. or a mixture of these different polymers.

According to another embodiment, reactive systems may also be used as thermoadhesive polymers such as styrene-ethyl acrylate, melamines, aziridine, isocyanates, unsaturated polyesters, epoxy resins or, more generally, any polymer having a reactive function.

The dispersion is a mixture of solvents, plasticizers, fatty acids and ammonium polyacrylates. It contains . also Theological and Thixotropic.

The mixture of these various components forms a paste which must be homogeneous and the components must not be separated during the execution of the process.

The viscosity of the paste decreases as it passes through the frame, after which said viscosity 30 increases and the volume of the coating point increases as it passes through the furnace.

. ·· *. The thickness of the second frame device 113, which ···. The thickness of the upper layer depends on the density of the coating point locations.

For a 30 mesh coating (about 200 dots / m2), the thickness of the second frame device 113 is preferably 10 to ·. 13 hundredths of a millimeter.

134444 The 11 mesh coating (20 points / m2) uses a frame with a thickness of 16 to 20 hundredths of a millimeter.

The amount of polymer 5 to be applied to the lower layer is 1 to 4 g / m2 and the amount of polymer to be applied to the upper layer is 4 to 14 g / m2.

The present invention enables the production of thermoadhesive fabric coatings in which the polymeric point sites are precisely distributed.

They ensure considerable expansion, high volume, good flexibility and good elasticity of the textile complex in which they are part.

• ·

Claims (9)

114440 14 A method for producing a thermoadhesive fabric cover (1), wherein the textile support (2) is superimposed on a dot (3) by split thermoadhesive polymers, characterized in that: - the textile support (2) is attached to a conveyor belt (100); having good dimensional stability; applying a lower layer (4) of spot-dispersed thermostable polymers 10 to the textile support (2) by a first rotary frame device (112); the polymers of the lower layer (4) after being placed on the textile support (2) are at least dried and / or partially cross-linked; 15. applying the upper layer (5) of thermoadhesive polymers which are uniformly punctured with respect to the lower layer (4) on the former layer by a second rotary frame device (113); the perforating dimension of the second rotary frame device (113) being equal to or less than the perforation dimension of the first frame device (112); the speed of rotation of the second rotary frame device (113), its mounting angle and the transport »·. the speed of the belt (100) is controlled by the speed of rotation of the first rotary frame device (112) so that the peripheral speeds of said frame devices (112, 113) correspond to the propagation speed of the conveyor belt (100) and so that each upper point (5) on the coating point of the layer (4); 30. a coated textile support (2, 4, 5) disengaged from the conveyor belt (100); - coated textile support (2, 4, 5) for transport *. 'Is passed through a continuous drying oven and then cooled. »•» · f I • $ f * I 114440 15 Method according to Claim 1, characterized in that the conveyor belt (100) forms a closed loop. Method according to Claim 2, characterized in that the conveyor belt (100) is washed after removal from the coated textile support (2, 4, 5) before attaching the new coated textile support (2). Method according to one of Claims 1 to 3, characterized in that the lower layer (4) contains at least one substance which is capable of reacting chemically with the thermoadhesive polymers of the upper layer (5). A thermoadhesive fabric covering comprising a textile support (2) and a thermoadhesive coating disposed on a single point (3) on one surface, characterized in that each coating point (3) comprises dried and / or crosslinked thermostable polymers. a lower layer (4) 20 and an upper layer (5) formed from thermoadhesive polymers; that the polymers of the lower layer (4) have been dried and / or cross-linked prior to application of the upper layer (5) according to any one of claims 1-5. according to the method; and that the upper layer (5) of each point has a surface area smaller than the area of the lower layer (4). The thermoadhesive fabric cover according to claim 5, characterized in that the thermoadhesive properties of the upper layer (5) change progressively from the contact region with the lower layer towards the upper region. . · * ·. Thermo-adhesive fabric covering according to claim 5 or 6, characterized in that the lower layer (4) contains polymers belonging to the group of 35 consisting of crosslinkable silicones, * '*: fluorinated polyethylenes, crosslinkable polyurethanes and polyacrylates. 16 1 1 4440 Thermoadhesive fabric covering according to any one of claims 5 to 7, characterized in that the upper layer (5) contains polymers belonging to the group consisting of polyamides, copolyamides, polyesters, copolyesters, polyurethanes and polyethylenes. Thermoadhesive fabric covering according to one of Claims 5 to 7, characterized in that the upper layer (5) contains polymers having a reactive function 10, which belong to the group consisting of styrene-ethyl acrylate copolymers, melamines, aziridine, isocyanate and isocyanate, . »»> I * i · »• t • * • • • '' • 114440 17