PROCESS FOR MOULDING A COMPOSITE PRODUCT FOR COATINGS

Abstract

Process for moulding a composite product (9) for coatings, comprising providing an aesthetic layer (1) comprising an aesthetic material chosen from: natural leather, a first composite material comprising a textile layer and a coating layer comprising polyurethane or polyvinyl chloride or thermoplastics olefins and a second composite material comprising a non-woven fabric comprising polyester or polyamide fibres immersed in a polyurethane matrix, with the polyurethane in weight percentage greater than or equal to 15% and less than or equal to 60% and the polyester or the polyamide in weight percentage greater than or equal to 40% and less than or equal to 85%, providing a support layer (2) comprising a solid polyolefin thermoplastic foam, providing a semi-finished product (3) comprising the aesthetic layer (1) and the support layer (2) coupled together, heating the semi-finished product (3) to bring the support layer (2) to a plastic state, forming the semi-finished product (3) by pressing against each other a first (11) and a second half-mould (12) of a mould (10) with the semi-finished product (3) interposed between the conformation surfaces (13) of the two half-moulds, and with the support layer (2) in the plastic state, cooling the semi-finished product (3) to bring the support layer (2) to a solid state and to realize the composite product (9).

Claims

1. Process for moulding a composite product for coatings, the process comprising: providing an aesthetic layer comprising an aesthetic material selected from the following group of materials: natural leather, a first composite material comprising a textile layer and a covering layer comprising polyurethane or polyvinyl chloride or thermoplastic olefins and a second composite material comprising a non-woven fabric comprising polyester or polyamide fibres immersed in a polyurethane matrix, wherein said polyurethane is in weight percentage greater than or equal to 15% and less than or equal to 60% and said polyester or said polyamide is in weight percentage greater than or equal to 40% and less than or equal to 85%; providing a support layer comprising a polyolefin thermoplastic solid foam; providing a semi-finished product comprising said aesthetic layer and said support layer coupled together; providing a mould comprising a first and a second half-mould each having a respective conformation surface; heating said semi-finished product to bring said support layer to a plastic state; forming said semi-finished product by pressing said first and second half-mould against each other with said semi-finished product (3) interposed between said conformation surfaces, and with said support layer in said plastic state; subsequently to said forming, cooling said semi-finished product to bring said support layer to a solid state and to realize said composite product.

2. Process according to claim 1, wherein the first and the second composite material are artificial leather, wherein said aesthetic layer is in single piece and it is entirely made of said aesthetic material, wherein said composite product comprises said support layer in the solid state as sole layer having self-supporting function, and wherein in said second composite material a sum of the weight percentages of said polyurethane and of said polyester or said polyamide is greater than or equal to 95%, preferably it is equal to 100%, of a whole mass of said second composite material.

3. Process according to claim 1, wherein said textile layer of the first composite material is woven fabric or knitted fabric or non-woven fabric, wherein said textile layer of the first composite material is made of synthetic textile fibres or of natural textile fibres, wherein said fibres of said second composite material are entirely of polyester, preferably they are coagulated polyester fibres, wherein said fibres of said second composite material have diameter less than or equal to 50 m, and wherein said foam is made of polypropylene or polyethylene.

4. Process according to claim 1, wherein said first composite material is Feel Tek, wherein said second composite material is selected from the following: Alcantara, Ultrasuede, and wherein said foam is Trocellen vertical.

5. Process according to claim 1, wherein said aesthetic layer, before said heating said semi-finished product, has thickness greater than or equal to 0.5 mm and less than or equal to 1.3 mm, and density per unit surface greater than or equal to 180 g/m2 and less than or equal to 280 g/m2, wherein before said forming said semi-finished product, a thickness of said support layer is greater than or equal to 1.5 mm and less than or equal to 2.5 mm.

6. Process according to claim 1, wherein said foam is crosslinked with physical agents and it has closed cells, and wherein said foam, before said heating said semi-finished product, has: density greater than or equal to 40 kg/m3, and less than or equal to 90 kg/m3; longitudinal tensile strength measured according to ISO 1798 standard greater than or equal to 0.5 MPa, and less than or equal to 2 MPa; transversal tensile strength measured according to ISO 1798 standard greater than or equal to 0.3 MPa, and less than or equal to 1 MPa; longitudinal strain at break measured according to ISO 1798 standard greater than or equal to 400%, and less than or equal to 600%; transversal strain at break measured according to ISO 1798 standard greater than or equal to 300%, and less than or equal to 450%; compression stress at 25% strain measured according to ISO 3386/1 standard greater than or equal to 30 kPa, and less than or equal to 50 kPa; compression stress at 50% strain measured according to ISO 3386/1 standard greater than or equal to 70 kPa, and less than or equal to 90 kPa; dimensional stability measured according to ISO 2796 standard greater than or equal to 120 C., and less than or equal to 140 C.

7. Process according to claim 1, wherein said semi-finished product, before said forming said semi-finished product, has substantially planar shape, wherein it is provided arranging said semi-finished product with said aesthetic layer and said support layer firmly adhered to each other, wherein said providing said semi-finished product comprises firmly adhering said aesthetic layer and said support layer to each other by means of a flame adhesion process comprising: superficially heating said support layer, to bring at least one face of said support layer to a plastic state, subsequently, placing said aesthetic layer on said face in said plastic state, cooling said face to solidify said face and to obtain adhesion; or wherein said providing said semi-finished product comprises firmly adhering said aesthetic layer and said support layer to each other by means of an adhesive layer.

8. Process according to claim 1, wherein said heating said semi-finished product is performed outside said mould (10), wherein said process, before said heating said semi-finished product, comprises fixing said semi-finished product to a support frame, wherein said heating said semi-finished product is performed with said semi-finished product fixed to said support frame, wherein said heating said semi-finished product comprises bringing said support layer and said aesthetic layer to respective mutually different temperatures, wherein said heating said semi-finished product comprises providing heat directly to said support layer, preferably by irradiation, and it comprises bringing said support layer to a temperature greater than or equal to 180 C., and less than or equal to 240 C., and wherein said heating said semi-finished product comprises providing heat directly also to said aesthetic layer, preferably by irradiation, to bring said aesthetic layer to a temperature greater than or equal to and less than or equal to 110 C.

9. Process according to claim 8, wherein said forming said semi-finished product is performed with said semi-finished product fixed to said support frame, and wherein, during said forming, each of said aesthetic layer and support layer is arranged directly in contact with a respective conformation surface.

10. Process according to claim 1, wherein said cooling said semi-finished product is performed by means of at least one of said first and second half-mould placed at temperature lower than a temperature of said aesthetic layer as a consequence of said heating said semi-finished product.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0066] FIGS. 1-3 show in a purely schematic way some exemplary steps of a process for moulding according to the present invention;

[0067] FIG. 4 shows in a purely schematic way a composite product for coatings obtained by means of the process of FIGS. 1-3.

DETAILED DESCRIPTION OF SOME EMBODIMENTS OF THE INVENTION

[0068] The features and the advantages of the present invention will be further clarified by the following detailed description of some embodiments, presented by way of non-limiting example of the present invention, with reference to the attached figures (not to scale with regard to the shown elements).

[0069] An exemplary process for moulding a composite product 9 (FIG. 4) according to the present invention is described in the following, wherein FIGS. 1-3 show in a purely schematic way some sections of elements used in the process.

[0070] The process for moulding exemplarily comprises providing a mould 10 comprising a first half-mould 11 and a second half-mould 12 (schematically shown in FIGS. 2 and 3), each half-mould having a respective conformation surface 13.

[0071] Exemplarily it is provided providing an aesthetic layer 1 (only schematically shown) in single piece entirely made of an aesthetic material selected from the following group of materials: natural leather, a first composite material comprising a textile layer and a covering layer comprising polyurethane or polyvinyl chloride or thermoplastic olefins and a second composite material comprising at least a non-woven fabric comprising polyester or polyamide fibres immersed in a polyurethane matrix, wherein the polyurethane is in weight percentage greater than or equal to 15% and less than or equal to 60% and the polyester or the polyamide is in weight percentage greater than or equal to 40% and less than or equal to 85%.

[0072] Typically both the first and the second composite materials are artificial leather.

[0073] In particular, the first composite material recalls natural fur-free leather. For example, the first composite material can be Feel Tek, in which the textile layer can be made of woven fabric and comprise natural fibres (e.g. cotton) and the covering layer is made of polyurethane.

[0074] In particular, the second composite material recalls natural suede leather. For example, the second composite material can be Alcantara, in which the fibres are entirely coagulated polyester fibres with diameter less than 50 m, wherein the polyurethane is in weight percentage equal to 32% and the polyester is in weight percentage equal to 68%.

[0075] Alternatively, the second composite material can be Ultrasuede.

[0076] Exemplarily it is further provided providing a support layer 2 (only schematically shown) comprising a solid thermoplastic foam entirely made of polypropylene cross-linked with physical agents (e.g. heat, ionizing radiations, etc.) and with closed cells. Exemplarily the foam of the support layer 2 is Tracellen vertical marketed by Trocellen GmbH.

[0077] Exemplarily it is provided providing a semi-finished product 3 comprising the aesthetic layer 1 and the support layer 2 firmly adhered to each other.

[0078] Exemplarily (not shown) providing the semi-finished product 3 comprises firmly adhering the aesthetic layer 1 and the support layer 2 to each other by means of a flame adhesion process comprising superficially heating the support layer, to bring at least one face of the support layer to a plastic state, subsequently placing the aesthetic layer on the face in the plastic state and finally cooling the face to solidify it and obtain the adhesion between the two layers.

[0079] In one alternative embodiment (not shown), providing the semi-finished product comprises firmly adhering the aesthetic layer and the support layer to each other by means of an adhesive layer, for example a polyolefin or polyurethane or neoprene adhesive.

[0080] Exemplarily it is provided heating the semi-finished product 3 to bring the support layer 2 to a plastic state.

[0081] Exemplarily, before heating the semi-finished product 3, the aesthetic layer 1 has thickness equal to about 0.8 mm and density per unit of surface equal to about 230 g/m.sup.2, and the support layer 2 has thickness equal to about 2 mm.

[0082] Exemplarily, before heating the semi-finished product 3, the foam has the following properties: [0083] density equal to about 67 kg/m.sup.3, [0084] longitudinal tensile strength measured according to ISO 1798 standard equal to about 1.07 MPa, [0085] transversal tensile strength measured according to ISO 1798 standard equal to about 0.63 MPa, [0086] longitudinal strain at break measured according to ISO 1798 standard equal to about 500%, [0087] transversal strain at break measured according to ISO 1798 standard equal to about 378%, [0088] compression stress at 25% strain measured according to ISO 3386/1 standard equal to about 43 kPa, [0089] compression stress at 50% strain measured according to ISO 3386/1 standard equal to about 83 kPa, [0090] dimensional stability measured according to ISO 2796 standard equal to about 130 C.

[0091] Exemplarily the process, before heating the semi-finished product 3, comprises fixing the semi-finished product to a support frame 14 (schematically shown in FIGS. 1-3). Exemplarily the support frame keeps the semi-finished product under tension. Optionally (not shown), for example in case of moulding of composite products having surface geometries with wide three-dimensional development (e.g. with pronounced ridges and/or valleys, which require an abundance of material), the semi-finished product can be fixed to the support frame to create a more or less pronounced loop (in order to provide such abundance of material for the moulding).

[0092] Exemplarily (FIG. 1) heating the semi-finished product 3 is performed outside the mould and with the semi-finished product fixed to the support frame 14.

[0093] Exemplarily heating the semi-finished product comprises providing heat by irradiation directly to the aesthetic layer 1 and to the support layer 2. For this purpose, it is exemplarily provided arranging two heaters 20 (schematically shown in FIG. 1) at opposite sides of the semi-finished product to be able to heat it without contact.

[0094] Exemplarily heating the semi-finished product comprises bringing the support layer 2 and the aesthetic layer 1 to respective different temperatures, wherein the support layer is brought to a temperature equal to about 210 C. (to bring the support layer to the plastic state) and the aesthetic layer is brought to a temperature equal to about (to facilitate the forming of the aesthetic layer without damaging it and/or to limit the thermal stress to which the semi-finished product is subjected).

[0095] Once the semi-finished product 3 has been heated, it is exemplarily provided, with the semi-finished product fixed to the support frame 14, arranging the semi-finished product between the two half-moulds arranged in an open configuration (FIG. 2).

[0096] Exemplarily (FIG. 3) it is subsequently provided forming the semi-finished product 3 by pressing the first 11 and the second half-mould 12 against each other with the semi-finished product interposed between the conformation surfaces 13, and with the support layer 2 in the plastic state.

[0097] Exemplarily forming the semi-finished product 3 is performed with the semi-finished product fixed to the support frame 14 (FIG. 3) to facilitate the forming and/or the subsequent removal of the finished product from the mould.

[0098] Exemplarily, during the forming phase, the aesthetic layer 1 and the support layer 2 are arranged directly in contact with a respective conformation surface 13.

[0099] Subsequently, it is exemplarily provided cooling the semi-finished product 3 to bring the support layer 2 (again) to a solid state and to realize the composite product 9.

[0100] Exemplarily cooling the semi-finished product is performed by means of both the first 11 and the second half-mould 12 kept (e.g. by thermal inertia or by means of a cooling system) at a lower temperature than the temperature of the aesthetic layer 1 as a consequence of the heating of the semi-finished product 3 (e.g. the temperature of the half-moulds is about 20-25 C.).

[0101] Finally, it is exemplarily provided opening the mould and removing the composite product 9 (e.g. by means of the support frame 14 to which the composite product is still fixed). Optionally (not shown) the composite product (before and/or after being removed from the mould) can be subjected to finishing operations, for example smoothing and/or cutting of any protruding portions of the aesthetic layer and/or of the support layer, to adapt it to the manufacturing standards.

[0102] With reference to FIG. 4, the composite product 9 comprises the aesthetic layer 1 and the support layer 2 in the solid state after the aforementioned cooling. Exemplarily the composite product 9 comprises the support layer 2 in the solid state as sole layer having self-supporting function.