EP1401657A1

EP1401657A1 - Complex material for coating surfaces

Info

Publication number: EP1401657A1
Application number: EP02747541A
Authority: EP
Inventors: Philippe Sanial; Olivier Ferrand
Original assignee: Textiles et Plastiques Chomarat SA
Current assignee: Textiles et Plastiques Chomarat SA
Priority date: 2001-06-21
Filing date: 2002-06-20
Publication date: 2004-03-31
Also published as: FR2826381B1; WO2003004267A1; FR2826381A1

Abstract

The invention concerns a complex material for coating surfaces, consisting of a multilayer complex comprising a lower layer called base layer, designed to be in contact and/or associated with a surface to be coated, layer which provides comfort, impact absorption, soundproofing, and which is covered with a surface layer providing the material with its visual appearance (decorative) as well as characteristics of abrasion and scratch resistance, said layers closely adhering to each other and being based on synthetic polymers selected from the family of polyolefins, and more particularly based on polyethylene. The invention is characterised in that the surface layer associated with the base layer consists itself of a complex comprising at least two layers of a polyolefin composition, said layers closely adhering to each other and the lower layer designed to be associated with the base layer comprises fillers, is coloured or printed and has an embossed appearance; the upper layer which is associated with it is based on a similar unfilled composition, optionally coloured, and which exhibits a translucent property.

Description

COMPLEX MATERIAL FOR COATING SURFACES.

Technical area

The present invention relates to a new type of material which can be used for coating surfaces.

It relates more particularly to a material which can be used in the automobile sector for coating the internal walls of a vehicle, such as in particular the passenger compartment floor, the dashboard, the door panels, etc. ., such a coating having the function not only of ensuring the finish, but also of producing both sound and thermal insulation of the passenger compartment of the vehicle.

The invention relates to a new type of coating which can be used for such an application, this coating being able not only to be used to cover flat surfaces, but above all presenting possibilities of shaping, in particular by molding.

PRIOR ART Numerous proposals have been made to date for producing complex sheet structures intended to be used as surface coating of the internal walls of the passenger compartment of a vehicle.

In this area of surface coatings, it has long been proposed to use complexes based on synthetic materials, such as for example polyvinyl chloride (PVC) or the like, generally associated with a reinforcement structure which can be either embedded in the mass of the material, or attached against the reverse side of the latter.

Very often, this reinforced or unreinforced thermoplastic sheet is associated with an under-layer, in particular of foam, in order to improve comfort and thermal and / or sound insulation. Among the various proposals made to date, there may be mentioned that which is the subject of patent EP 968 875 in the name of the Applicant which relates more particularly to a complex, intended more specifically for coatings of the floor of the passenger compartment of the vehicle and which includes a lower layer called "support layer" intended to be in contact with the surface to be coated and ensuring comfort, shock absorption, soundproofing, and which is covered with a surface layer, capable of receiving a decoration , the visible face possibly having a smooth, shiny or matt appearance and / or seed, appearance obtained simultaneously with the production of the complex o without further treatment.

In such a material, the support layer and the surface layer are intimately linked to each other and are produced from constituents selected from the family of synthetic polymers based on polyolefins, and more particularly based on polyethylenes. .

The two layers are combined together by complexing the two constituents during the extrusion of the surface sheet, the complexing being carried out by calendering immediately at the exit of the extruder from the surface film, o while the latter is still at high temperature.

Preferably, the surface layer of the complex which therefore comprises the decoration consists of a composition comprising a mixture of low density polyethylenes, high density polyethylenes, and fillers, while the support layer intended to be in contact with the surface to be coating is, in turn, based on a composition of low density polyethylene highly loaded.

Statement of the invention

Now we have found, and this is what is the subject of the present invention, an improvement made to this type of complex material which not only makes it possible to accentuate, modify and obtain new types of decoration. surface, while retaining the characteristics of the material which is the subject of the patent aforementioned European, namely sound and thermal soundproofing, conformability, abrasion and puncture resistance, ease of maintenance, high stability after installation while being perfectly recyclable.

In general, the material according to the invention therefore consists of a multilayer complex comprising a lower layer called the "support layer", intended to be in contact and / or associated with a surface to be coated, a layer ensuring comfort, shock absorption, soundproofing, and which is covered with a surface layer communicating to the material its visual appearance (decor) as well as the characteristics of resistance to abrasion, to scratches, the said layers being intimately linked to each other and being based on synthetic polymers selected from the family of polyolefins, and more particularly based on polyethylene.

The material according to the invention is characterized in that the surface layer associated with the support layer itself consists of a complex comprising at least two layers of a composition based on polyolefin, said layers being intimately linked one to each other and:

• the lower layer intended to be associated with the support layer comprises fillers, is colored or printed and has a seed appearance; the upper layer which is associated with it is based on a similar composition, uncharged, possibly colored, and which has the characteristic of being translucent.

The graining of the lower layer is preserved in the final complex, because the lower and upper layers are arranged by successive operations, and not by coextrusion.

Preferably, the two layers of the surface layer are produced from a composition based on low density polyethylene and high density polyethylene. According to the invention, the translucent upper layer of the surface layer can be colorless, colored, smooth or grainy. It can also receive an impression on an action of its surface, while remaining translucent in the unprinted areas. i

Furthermore, it is possible to incorporate between the translucent upper surface layer and the lower sub-layer which is associated with the support layer, a perforated textile sheet such as a knitted structure in the form of a net making it possible to give the together a textile aspect. 0

In accordance with the invention, the formulation of the different layers forming part of the complex may vary depending on the final properties which it is desired to obtain depending on the area of the vehicle where the coating is to be exposed.

5 Way of realizing the invention

The invention and the advantages which it provides will however be better understood thanks to the concrete examples of embodiment given below, by way of indication but not limitation.

0 To produce a complex in accordance with the invention, in a first operational phase, a first complex is produced, in accordance with the teachings of EP 968 875, comprising a support layer proper intended to be in contact and / or associated with the surface to be coated, based on a composition of low density polyethylene, highly charged, coated with a layer of "surface" based on a composition comprising a mixture of low density polyethylene / high density polyethylene and fillers.

Regarding the support layer, it is therefore based on highly charged polyethylene, the amount of fillers, for example consisting of o barium sulfates, being of the order of 80% by weight relative to the support formed. Such a support layer has a surface mass which can vary from 1.5 to 8 kilograms per square meter, or even more, a sheet weighing of the order of 2 to 5 kg / m ² suitable for most applications.

The density of this charged structure can be between 1 and 3 and is advantageously equal to 2.

Optionally, a non-woven support or other textile structure, preferably also based on polyethylene or porypropylene, can be incorporated into this sublayer, thereby improving the mechanical performance of the complex and in particular the resistance to puncturing.

This first complex therefore constitutes the support layer of the coating material according to the invention.

Regarding the surface layer, it therefore consists of a complex comprising at least two layers of a composition based on low density polyethylene and high density polyethylene, said layers being intimately linked to each other.

Regarding the lower layer, intended to be associated with the support layer, it is therefore also based on polyolefin, its formulation being such that it comprises approximately 10 to 12% of fillers, such as calcium carbonate for 58 to 83%. of low density polyethylene and 5 to 30% of high density polyethylene, high density polyethylene bringing an increase in the hardness of the sheet.

The surface mass per square meter of this first surface sheet can be between 100 and 800 g / m ² , or even more, but in general it is of the order of 300 to 500 g / m ² . This sheet which is intended to give the product, at least in part, its visible decoration is seed and is preferably colored.

The coloring will be obtained by incorporation of pigments and the effect may be accentuated by the incorporation of particles conferring a pearly colored appearance, a metallic appearance, a marbled appearance, etc.

According to the invention, this first surface layer is covered with a second layer also based on a composition of low density polyethylene and high density polyethylene, but which has the characteristic of being translucent and therefore does not contain any filler .

This layer, which therefore forms the final surface of the complex, can optionally also be colored.

It has been found that the presence of such an additional translucent layer leads to a product in which the decoration which the intermediate layer associated with the support comprises, is much more pronounced and also gives a depth effect. The graining of the lower layer also appears through the upper layer, thus increasing the depth effect.

Optionally, an openwork textile structure where the decorative material can be interposed between the two layers based on the composition low density polyethylene and high density polyethylene.

Example 1

A complex is produced in accordance with the invention under the following conditions.

In a first operational phase, in accordance with the teachings of EP 968 875, a first complex is produced comprising a support consisting of a sheet of polyethylene previously produced and comprising: 20% polyethylene, - 80% filler consisting of calcium carbonates.

The surface mass of this support is 3.7 kg / m ² and it has a thickness of the order of 2 mm. Its density is around 2.

It includes a reinforcement consisting of a nonwoven, based on polypropylene and weighing 30 g / m ² .

With this support, on a calendering installation arranged downstream of an extruder, an extruded film is associated at a temperature of 230 ° C. and consisting of a composition comprising:

12% of calcium carbonate filler; 78% low density polyethylene; and - 10% high density polyethylene.

In this basic composition, pigments, dyes, particles (such as mica, oxide, aluminum) are also incorporated, imparting to this sheet its decoration such as a pearly, colored or other appearance.

The weight of the extruded sheet is, after stretching, 500 g / m2 and it is combined by calendering while being in contact with the steel cylinder of the calender.

Its thickness is 0.55 mm. The speed of rotation of the calender rolls is such that a production of 5 m / min is obtained. The temperature of the steel cylinder of said calender is 30 ° C.

The surface of one of the calendering cylinders is grained to give the additional embossing in relief to the lower layer of the surface sheet.

After calendering, a basic complex is obtained comprising on the surface a grained sheet providing the decor for the product. The complex thus produced, still by extrusion, a second film is also added to the surface of the layer forming the decoration, also consisting of a composition of low density polyethylene and high density polyethylene, at a rate of 70% of low density polyethylene and 30% of high density polyethylene.

According to the invention, this sheet is translucent and therefore does not contain any filler.

It is found that, after lamination, that the decoration of the sub-layer is reinforced, this decoration being constituted by the coloring of the first layer of the surface complex, in the present case of smooth pearly anise color.

Example 2

Example 1 is repeated, except that with the decorative layer associated with the support layer which is also colored in a smooth pearly anise tone, two layers weighing 450 g / m ^{2 are} made from a composition also comprising 70% of low density polyethylene and 30% of high density polyethylene, also unfilled in order to remain translucent.

The two translucent layers are added consecutively by calendering and have a surface effect obtained by graining. It can be seen that the smooth pearly appearance is accentuated by the presence of these translucent layers.

Example 3 A complex is produced comprising a support layer similar to that of Example 1 associated with an intermediate sheet. This intermediate sheet is produced from a composition comprising 78 parts of low density polyethylene, 10 parts of high density polyethylene, 12 parts of fillers such as mica particles, oxide, and 1.5 parts of dye giving a white coloring.

This intermediate sheet which therefore gives the decor is grained. On a radiator grille, a translucent surface sheet, also grained, is added, based on a composition comprising 70% low density polyethylene and 30% high density polyethylene. This leaf is grainy and is colored in fluorescent green.

A complex is obtained, the decoration colored green presents a very pronounced and irregular neon green appearance.

Example 4 Example 3 is repeated, except that the intermediate sheet of 400 g / m ² is colored in aluminum metal and is also grained.

A coating with a deep metallic appearance is also obtained.

Example 5

Example 4 is repeated except that there is interposed between the two sheets constituting the surface layer, namely the base sheet comprising the decoration, colored in this case in aluminum metal, and the translucent upper sheet. grained, an openwork textile constituted by a net.

Laminating is also carried out by calendering at the outlet of the surface layer extrusion die.

The top layer is also grained.

A complex is obtained in which the openwork fabric has a pronounced effect through the colorless translucent layer which is grainy.

The complexes obtained in accordance with the invention can be produced to produce all types of internal coatings for vehicle interiors, such as as floor mats, be associated with a molded structure intended to form the dashboard, door panels, or even the vehicle roof.

If in the previous examples, the invention has been described with a support layer forming a heavy mass for certain applications, it could be envisaged, for example in the case where it is desired to make a seat covering, to have a support layer based on expanded polypropylene foam.

Of course, the invention is not limited to the examples described above, but it covers all the variants produced in the same spirit.

Claims

1 / Complex material for coating surfaces, consisting of a multilayer complex comprising a bottom layer called "support layer", intended to be in contact and / or associated with a surface to be coated, layer ensuring comfort, shock absorption , soundproofing, and which is covered with a surface layer communicating to the material its visual appearance (decor) as well as the characteristics of resistance to abrasion, to scratches, the said layers being intimately linked to one another. the other and being based on synthetic polymers selected from the family of polyolefins, and more particularly based on polyethylene, characterized in that the surface layer associated with the support layer is itself constituted by a complex comprising at least two layers of a polyolefin-based composition, said layers being intimately linked to each other and:

• the lower layer intended to be associated with the support layer comprises fillers, is colored or printed and has a seed appearance;

• the upper layer associated with it is based on a similar composition, uncharged, possibly colored, and which has the characteristic of being translucent.

2 / Complex material according to claim 1, characterized in that the surface layer associated with the support layer, consists of a complex comprising at least two layers of a composition based on low density polyethylene and high density polyethylene.

3 / Material according to one of claims 1 and 2, characterized in that the upper layer is colorless.

4 / Material according to one of claims 1 and 2, characterized in that the translucent upper layer is colored. 5 / Material according to one of claims 1 and 2, characterized in that the translucent upper layer is smooth.

6 / Material according to one of claims 1 and 2, characterized in that the translucent upper layer is grained.

Il Material according to one of claims 1 and 2, characterized in that the translucent upper layer is printed on a fraction of its surface.

8 / Material according to one of claims 1 and 3 to 6, characterized in that the translucent surface layer is itself made up of a complex translucent, colorless, colored, smooth or grained bilayer.

9 / Material according to one of claims 1 to 8, characterized in that it comprises between the translucent upper surface layer and the lower layer which is associated with the support layer, a perforated textile sheet such as a knitted structure in net shape.