FR2460359A3 - Multilayer insulation cladding - needle-bonded to provide quilt-like appearance - Google Patents

Abstract

Quilted insulation cladding is produced by needle-bonding an upper, relatively thin, previously needled layer to at least one under-layer of thicker insulation using felting needles. The under-layers contain thermally shrinkable fibres, e.g. polypropylene, and the needling process is followed by a heat treatment. The quilted cladding has excellent thermal and acoustic insulation which may be used for wall cladding, motor car panels and roof linings.

Description

 The invention relates to a method of manufacturing insulating coatings with quilted effects and to the insulating coatings obtained.

 Decorative elements with a quilted aspect in relief are already known. These are generally complex multilayer elements in which two different techniques are used to bond the layers at the same time as the formation of a relief or quilting effect.

 According to one of these techniques, the different layers are stitched together.

Alternatively, and more particularly in the case where the various layers of the complex are made up at least in part of heat-weldable materials, the said layers are simultaneously fixed and the appearance of relief effect, by application of heat and pressure, for example by means of heated relief rollers (embossing technique), or by application of ultrasound, or by any other means provided for this purpose.

It is already known, on the other hand, to bring to pre-needled fibrous webs, certain three-dimensional effects by needling by means of fork needles, of round section, which, crossing the entire thickness of the web, show on the other side of it a drawing whose characteristics are predetermined by programming the machine. Figure 1 of the attached schematic drawing explains the mode of action of the fork needles for the conventional production of a needle punch, 2 designating the sheet of fibers having been subjected to a pre-needling and 3 the fork needles. thus obtains, on the face opposite to the entry of the needles, that is to say in 4, a loop effect and it is the variation of the height of these loops, determined by the variation of the penetration of said needles, which determines the structure of the relief effect obtained, generally in the form of loop pile, as shown in FIG. 2 which is a perspective view of a needle punch with conventional relief.

 In this process, we therefore work on the back of the sheet to obtain the desired relief effect at the location.

 The aim of the present invention is to produce coatings with quilted effects having, inter alia, good insulation properties, both thermal and acoustic.

 Thus it has for its object a process for the production of padded insulating coatings by application of the aliquid technique. Flooring in which a thin surface layer is bonded, according to a previously programmed quilting pattern, at least a thicker insulating sublayer by action, on said surface layer constituting the location of the complex, of felting needles.

According to a particular characteristic of the invention, the surface layer consists of a relatively thin, pre-needled sheet of fibers that are not very sensitive to heat and chosen from natural fibers or synthetic fibers of the polyester or polyamide type, and the sublayer is consisting of a thick layer comprising a minimum percentage of heat-shrinkable fibers such as, among others, polypropylene fibers. The quilting operation by the action of felting needles can optionally be followed by a heat treatment operation between 1500 and 2000C and preferably around 1800C (the temperature chosen depends on the retractable fiber used) during which there is a retraction of the fibers of the underlay thus accentuating the relief effect obtained by quilting: this retraction can be exerted freely or with a control of the residual surface.

 There are thus coatings with excellent insulation properties, both thermal and phonic, and whose fields of application are very varied, whether they are insulating wall coverings, panels, plates used in industry. and more particularly in the automobile industry (as in this last field for the decoration of pavilions).

 The invention also relates to these coatings.

The present invention will be better understood moreover and its advantages will emerge clearly from the description which follows, with reference to the appended schematic drawing in which
Figure 3 shows an assembly of needles allowing the implementation of the method of manufacturing insulating coatings according to the invention.

 Figure 4 is a view of the coating of Figure 3 after needling.

Figures 5 and 6 are schematic perspective views of the coating obtained, respectively before and after application of the heat treatment.

In the figures, 5 is the surface layer, 6 the insulating sublayer and 7 the felting needles.

On a needling machine, the needles 7 of which are made up of large-size felting needles, such as
15-18-25 and having a drawing programming installation, there is a first thick layer 6 which is a needled felt with a weight per m2 of 700 grs and a thickness of 2 cm.

 This felt consists of a mixture of various fibers comprising at least 60% of polypropylene fibers.

Needleloom felt could of course, without harming the invention, be replaced by a conventional felt or a nonwoven obtained by other techniques; lthickness of this underlay which can vary from 5 mm to 3 cms and its weight per m2 from 350 to 1500 grs.

On this layer 6 is disposed a surface layer 5 2.5 mm thick and weighing 300 grs / m2. it is a flat needled polyester fiber.

Without harming the invention, the thickness of this surface layer can vary between 2 and 3 mm and its weight per m2 between 200 and 400 g. it is obvious that it is possible to use guillea, flat or looped ai, based on fibers other than polyester, for example based on polyamide; the only requirement to be met is that the fibers constituting this surface layer 5 are not shrinkable at a temperature of 1800C,
The sub-layer 6 and surface layer 5 assembly is subjected to the action of the felting needles 7 which, according to the programmed drawing, bond the surface layer 5 to the sub-layer 6.

 The needling program displayed makes it possible to produce a drawing, the relief 8 of which appears on the surface layer (FIGS. 4 and 5) in the manner of the quilting conventionally obtained by stitching-stitching.

 The coating thus obtained is then subjected to a heat treatment on a conventional installation, (not shown).

This heat treatment, during which the complex obtained is brought to a temperature of around 1800C results in a shrinkage of the underlayer 6 while the surface layer 5 which does not contain thermally shrinkable fibers, is blocked at the points needling and puckered out of the needling points, thus reinforcing the quilting effect previously communicated by the felting needles (Figure 6).

 As is obvious and as is clear from the above, the present invention is not limited to the single embodiment of the coating described above, by way of example. On the contrary, it embraces all of the variant embodiments thereof, whatever the quilting pattern in particular, the nature of the fibers constituting the surface layer and the sub-layer as well as the weight per m2 and the thickness of each of these layers. The quilted complex thus obtained can, of course, comprise other surface and / or reinforcement layers applied by any process known per se and intended to increase its insulation capacity or its decorative appearance.

Claims (3)

- CLAIMS  1 - Process for manufacturing padded insulating coatings by applying the needling technique, characterized in that a thin surface layer is linked, according to a previously programmed quilting pattern, to at least one more insulating underlay thick by action, on said surface layer constituting the location of the complex, of felting needles. 2 - Method according to claim i, characterized in that the surface layer consists of a relatively thin prepunched web of fibers relatively insensitive to heat and chosen from natural fibers or synthetic fibers of the poster or polyamide type, that the underlay consists of a thick sheet comprising a minimum percentage of fibers capable of thermally shrinking such as polypropylene fibers and the quilting operation by the action of felting needles is followed by a treatment operation thermal between 1500 and 2000C and preferably around 1800C.  3 - Padded insulating coatings obtained by implementing the method according to claims 1 and 2.