CS262174B1 - A method for producing a backing fabric - Google Patents

Abstract

The solution relates to the field of textile technology. A fleece is layered between two longitudinally guided sets of threads, alternatively interspersed with another set of threads, made from a mixture of basic, heat-resistant fibers. Furthermore, binder fibers with a lower melting point, at least 20 °C compared to the basic fibers, are used. Then the textile is exposed to the influence of heat and pressure.

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for manufacturing a substrate bonded fabric for producing waterproofing webs from two longitudinally extending thread systems.

Several groups of base materials are used according to the difficulty of use in the production of waterproofing strips from the underlying cloth materials by impregnation or by the application of differently modified bitumen. Until recently, the most widespread substrate was the so-called rag board, from which it declines due to putrefaction processes for a short lifetime. Very efficient papermaking techniques are used further, but in the processing of glass fibers, for example according to U.S. Pat. No. 4,242,404. However, a greater spread has encountered the problem of too low ductility of the material, which in some cases leads to formation of uneven dilatation conditions. cracks and loss of the main function, that is water tightness.

The basic requirements for current building and insulation technology are good mechanical properties. This is particularly the minimum elongation strength required at considerable stress through the impregnation line, where the bitumen has a temperature of about 180 ° C and could undesirably narrow the strip. Furthermore, it is resistant to microorganisms in the finished strip and good wettability with bitumen. At the same time, non-woven fabric belts made directly from the polymer, as well as polyester fiber fabrics and bonded fabrics according to U.S. Pat. No. 195,434, are closest to these requirements.

However, each of these materials has its drawbacks. Bonded fabrics made of polymer directly below the nozzle must be based on polyester and its processing in this way is very difficult. In addition, a good degree of fiber reinforcement is very difficult to achieve, so that both fibers and fabrics have a ductility of over 100% unless the formation is additionally bonded by adhesives in different forms. Therefore, during processing, unwanted width changes occur according to the strip tension during impregnation. Polyester fabrics can meet the requirements with an appropriate manufacturing process. However, the manufacture of both fabrics is the most economically demanding, both in terms of raw material requirements and low productivity technology. Therefore, the fabrics are used only to a very limited extent.

DOS No. 3,209,118 discloses a belt of synthetic fiber base fabric sandwiched between two outer layers of woven soft yarns. All layers are mutually interconnected. According to another German Patent Application No. 8,023,893, a fabric is combined with a non-woven fabric of short fibers on both sides for fabricating the belt. The combination of two different fabrics, of which the fabric is intended to provide the necessary strength and shape stability, is also protected by U.S. Patent 4,278,724. The whole is connected by bitumen.

The most serious economic and functional requirements are solved by MS. AO No. 195 434, in that the basic raw material is synthetic fibers of secondary raw materials, the reinforcing body of a thread system deposited in the form of loops, optionally in combination with a longitudinal system of threads.

A certain drawback of this production method is that a relatively high proportion of glass silk, yarn or sliver has to be used in the production. This means that good uniformity is possible only at higher basis weights of the fabric and also a high proportion of silk or yarn adversely affects the economic efficiency of otherwise very simple production.

These drawbacks are overcome by the method of manufacturing a backing fabric for waterproofing membranes using a layer of two yarn sets according to the invention. It consists in that a nonwoven web interleaved alternatively interspersed with a further set of yarns is formed between the two longitudinally threaded yarns formed of a mixture of basic, heat-resistant fibers and fibers having a lower melting point of at least 20 ° C against the basic fibers. the fabric is exposed to heat and pressure.

According to a further feature of the invention, the thread systems are formed of silk, yarn or strands of glass, polyester, polyamide or polyacrylonitrile fibers and a binder of polyamide, polypropylene or chlorinated polyvinyl chloride fibers.

This method as opposed to the method of art. AO No. 195 434 allows the use of binder instead of silk, the cost of which is almost twice as high as the staple, of an adequate polymer, preferably even cheaper secondary raw material from knitting and woven fabrics or from the primary production of polyamide fibers. In addition, the use of staple fibers for binder is much higher than for yarns, due to the considerable differences in their fineness and hence the ability to form joints at a higher frequency. The economic effect is therefore due to a reduction in the proportion of silk and the possibility to use almost exclusively secondary raw materials for production.

Example 1

A web of a mixture of polyester and polyamide fibers obtained as secondary raw materials by reprocessing waste at a rate of 50%: 50 ° / o is deposited by transverse layering on a system of glass fibers of fineness 1 00-0-dtex, which forms a warp with a spacing of 8 mm. . Simultaneously with the web, a 20 mm pitch of glass silk of fineness T00-0 dtex is deposited at 20 mm spacing. The shape is overlaid with another set of silk, spaced at equal spacing between the bottom spacing of the silk, and passes over a pair of heated rollers

WITH

Heated to 250 ° C. By pressing with a water-cooled pressure roller and trimming the edges, a non-woven insert with good strength and elongation in both directions is obtained, suitable for application with insulating materials.

Example 2

The procedure is as in Example 1 except that the ratio of the blend of polyester and polyamide fibers is 40%: 60% and the warp 1 transverse reinforcement produces 100 dtex polyester silk.

Example 3

The procedure is as in Example 1 except that the silk used for warp and transverse web reinforcement is formed by viscose silk having a fineness of 1220 dtex.

Example 4

A web of polyester, polyacrylonitrile and polyamide fibers of secondary raw materials and polypropylene fibers of split film in a ratio of 50%: 50% is deposited on a lengthwise guided system of polyester silk of 1100 dtex at 10 mm pitch. The formation is overlaid with a second set of 1100 dtex polyester silk and passes through a pair of heated rollers to a temperature of 180 ° C. By pressing in with a water-cooled pressure roller and trimming the edges, a non-woven insert suitable for coating with insulating materials is obtained at temperatures below 160 ° C.

Claims (1)

A method for producing a backing fabric from two sets of yarns and nonwoven fabrics with a fraction of binder fibers exposed to heat and pressure, characterized in that a web of interleaves interspersed with another set of yarns is sandwiched between two longitudinally guided yarns.