Stock material or miscellaneous articles – Coated or structually defined flake – particle – cell – strand,... – Rod – strand – filament or fiber
Patent
1994-08-17
1996-02-27
Dudash, Diana
Stock material or miscellaneous articles
Coated or structually defined flake, particle, cell, strand,...
Rod, strand, filament or fiber
428369, 428 662, 192107M, 427337, 427342, 4273898, 4273978, 156169, 156175, 156180, F16D 1360, D02G 302, B32B 1300, B05D 312
Patent
active
054947472
DESCRIPTION:
BRIEF SUMMARY
This invention relates to the treatment of textile products in the form of fabrics, yarns and cords. It is in particular concerned with the impregnation of such textile products with liquids containing particulate material. In the manufacture of mechanical rubber goods, belting and friction materials including clutch facings, it may be necessary to impregnate a textile product with rubber, resin and inert fillers, the textile product being thereafter incorporated into the finished article, for example by lamination and pressing.
The use of textile products as reinforcements for rubber/resin is well-known. Previously natural fibres were used for this, but it is now common practice to use a glass fibre fabric or strand, usually in admixture with organic fibres such as aromatic polyamides, polyimide, acrylic carbon fibres and/or cellulosic fibres and the like, either as discrete yarns, or more usually in the form of fibre blends. Before incorporation into a finished article by winding, lamination or by other means, it is necessary to impregnate the textile product with rubber and a curable resin together with such particulate fillers as are needed to ensure that conversion into the final article achieves good bonding and satisfactory properties.
Conventional impregnation practice typically requires the use of a solution of the rubber and resin (or resins) in a volatile organic solvent, in which is also dispersed any particulate fillers. The result is a relatively thick, viscous solution/suspension ("dope"). The textile product as a fabric or as a yarn or bundle of parallel yarns is impregnated by drawing it through a bath of this dope, prior to removal of the solvent by passage through a drying tower, or oven. The use of volatile organic solvents is not generally convenient, since they are costly, and the apparatus for handling them demands great care in its use and maintenance, as well as being subject to strict environmental controls.
It is an object of the present invention to provide an impregnation process which does not require the use of organic solvents.
According to this invention, a process for the impregnation of a textile product with a rubber and a resin and particulate filler material comprises the steps of dispersing the particulate filler and the resin in an aqueous rubber latex containing from 0.01% to about 30% by weight of a water-soluble silicate, said amount being based on the total weight of the dispersion, followed by passing the textile product through the aqueous dispersion thus formed.
The process further comprises the step of drying the dipped textile product, optionally after subjecting it to a treatment to at least partially coagulate the latex, for example a passage through an acidic solution, thereby helping to retain the particulate component on and/or within the impregnated textile product. The process is particularly suitable for making rubber and resin impregnated textile yarns or strands, although lengths of fabric, for example narrow fabric, may also be treated.
Particularly preferred rubber latices include carboxylated SBR and NBR; the resin is preferably a phenolic resin. A modified phenolic resin manufactured using an alkali to produce a resol resin is particularly preferred. The resin may also be modified by mixing with cashew nut shell liquid, and/or resorcinol, in known manner.
Surprisingly, it has been found that although the resin and fillers normally promote separation of the latex into an inhomogeneous mix of water and solids, the inclusion of a even very minor proportion of a water-soluble silicate has a significant effect on both the viscosity of the mixture and on its stability. Sodium silicate is particularly preferred and has proved satisfactory when used in amounts as low as 0.01% by weight, again based on the total weight of the dispersion.
The particulate fillers may be of the kind generally used, for example carbon black, barytes and graphite. However, it is also possible to employ a reactive filler system such as a metallic sulphate, for example alumini
REFERENCES:
patent: 3474616 (1969-10-01), Zeisberg
patent: 3766000 (1973-10-01), Gibson et al.
patent: 3818074 (1974-06-01), Ahlbrecht
patent: 3860442 (1975-01-01), Natta et al.
patent: 3925281 (1975-12-01), Jorgensen
patent: 3936542 (1976-02-01), Cox
patent: 3984366 (1976-10-01), Elmer
patent: 4026856 (1977-05-01), Jahnke
patent: 4045608 (1977-08-01), Todd
patent: 4118528 (1978-10-01), Lowry
patent: 4185135 (1980-01-01), Huff
patent: 4347285 (1982-08-01), Batdorf
patent: 4472243 (1984-09-01), Bondoc et al.
patent: 4632960 (1986-12-01), Sato et al.
patent: 5098758 (1992-03-01), Kani
patent: 5135780 (1992-08-01), Kissel
patent: 5217778 (1993-06-01), LaCasso
Dudash Diana
G B Tools & Components Exports Limited
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