Reinforcement product
AssigneeChomarat Composites
InventorsJerome Maupetit, Francisco Machado-Valente, Jacques Baudonnel
Life of this patent
Estimating the term…
Abstract
A reinforcing product includes a first layer (2) of reinforcing threads (3) parallel to each other and a second layer (4) of reinforcing threads (5) parallel to each other and transverse to the first layer (2). The reinforcing threads (3) in the first layer (2) are partially covered by a powder based on a thermoplastic or thermosetting material forming a bond firstly at points between the reinforcing threads (3) in the first layer (2), and secondly between the reinforcing threads (3) in the first layer (2) and the reinforcing threads (5) in the second layer (4).
Claims22
1- Reinforcing product (1) comprising a first layer (2) of reinforcing threads (3) parallel to each other and a second layer (4) of reinforcing threads (5) parallel to each other and transverse to the first layer (2, 2a),
- characterized in that the reinforcing threads (3, 3a) in the first layer (2) are partially covered by a powder (7) based on a thermoplastic or thermosetting material forming a bond firstly at points between the reinforcing threads (3) in the first layer (2), and secondly between the reinforcing threads (3) in the first layer (2) and the reinforcing threads (5) in the second layer (4).
2- Reinforcing product (1) according to claim 1, characterized in that it comprises a third layer (2b) of reinforcing threads (3b) parallel to each other and transverse to the first layer (2a), the reinforcing threads (5) in the second layer (4) being trapped between the reinforcing threads (3a, 3b) of the second (2a) and third (2b) layers and reinforcing threads (3b) in the third layer (2b) being partially covered by a powder (7) forming a bond firstly at points between the reinforcing threads (3b) in the third layer (2b ), and secondly between the reinforcing threads (3b) in the third layer (2b) and between the reinforcing threads (5) in the second layer (4)t.
3- Reinforcing product (1) according to claim 1, characterized in that the powder (7) covers less than 5%, and preferably less than 0.5%, of the surface area of the reinforcing threads (3a, 3b) in the first layer (2a) and possibly in the third layer (2b).
4- Reinforcing product (1) according to claim 1, characterized in that the reinforcing threads in each of the layers are adjacent to each other.
5- Reinforcing product (1) according to claim 1, characterized in that the reinforcing threads in each of the layers are arranged in roving to form a mesh.
6- Reinforcing product (1) according to claim 5, characterized in that the spacing of the roving in each of the layers is uniform and is between 0.5 and 20 cm.
7- Reinforcing product (1) according to claim 5, characterized in that roving of reinforcing threads (3a, 3b) in the first (2a) and in the third (2b) layers is coincident in superposed planes.
8- Reinforcing product (1) according to claim 5, characterized in that the roving of reinforcing thread (3a) in the first layer (2a) is offset by a half spacing from the roving of reinforcing thread (3b) in the third layer (2b).
9- Reinforcing product (1) according to claim 1, characterized in that the powder (7) is composed of grains (8) with an average diameter of between 50 and 500 μm.
10- Reinforcing product (1) according to claim 1, characterized in that the density of the powder (7) is between 0.9 and 2 g/cm3 and in that the mass of the powder (7) corresponds to 1 to 10% of the total mass of the reinforcing product (1).
11- Reinforcing product (1) according to claim 1, characterized in that the powder (7) is based on a thermosetting material selected from the group consisting of epoxy resins, urea-formol, vinyl polyacetate and unsaturated polyesters.
12- Reinforcing product (1) according to claim 1, characterized in that the powder (7) is based on a thermoplastic material selected from the group consisting of polyethylene terephthalate, polyamides, ethylenevinylacetate, and polyolefin resins.
13- Reinforcing product (1) according to claim 1, characterized in that the reinforcing threads (3a, 3b, 5) are made from a material selected from the group consisting of glass fibre, carbon, aramide, high strength polyethylene terephthalate and polyamide.
14- Reinforcing product (1) according to claim 1, characterized in that the reinforcing threads (3a, 3b, 5) are completely or partly textured or expanded.
15- Reinforcing product (1) according to claim 1, characterized in that it is associated with a surface or visible film on one or two of its faces.
16- Method for manufacturing a reinforcing product (1) according to claim 1, comprising the steps of:
- a) a first layer (2, 2a) of reinforcing threads (3,3a) parallel to each other, is made and then passed in powder (7) based on a thermoplastic or thermosetting material,
- b) the first layer (2, 2a) thus obtained is vibrated, in order to eliminate some of the powder (7) deposited on the surface of the reinforcing threads (3, 3a),
- c) a second layer (4) of reinforcing threads (5) parallel to each other is deposited on the first layer (2, 2a), the second layer (4) transverse to the first layer (2, 2a) without interlacing, and
- d) the two layers (2, 2a, 4) are assembled by thermocompression.
17- Method according to claim 16, characterized in that step c) is preceded by a step in which the first layer (2, 2a) is heated to a temperature just sufficient to soften the powder (7), and thus improve its attachment to the reinforcing threads (3, 3a).
18- Method according to claim 16, characterized in that the powder (7) is formed of grains (8) with an average diameter of between 50 and 500 μm.
19- Method according to claim 16, characterized in that the powder (7) is based on a thermoplastic material selected from the group consisting of polyethylene terephthalate, polyamides, ethylenevinylacetate, and polyolefin resins.
20- Method according to claim 16, characterized in that the powder (7) is based on a thermosetting material selected from the group consisting of epoxy resins, urea-formol, vinyl polyacetate and unsaturated polyesters.
21- Method according to claim 16, characterized in that after step b), the powder (7) covers less than 5%, and preferably less than 0.5% of the surface area of the reinforcing threads (3, 3a) in the first layer (2, 2a).
22- Part composed at least partly of a reinforcing product (1) according to claims 1 and a matrix made of a thermoplastic or thermoset material in relation with the reinforcing product (1).