Classifications

• • D—TEXTILES; PAPER
  • D04—BRAIDING; LACE-MAKING; KNITTING; TRIMMINGS; NON-WOVEN FABRICS
  • D04H—MAKING TEXTILE FABRICS, e.g. FROM FIBRES OR FILAMENTARY MATERIAL; FABRICS MADE BY SUCH PROCESSES OR APPARATUS, e.g. FELTS, NON-WOVEN FABRICS; COTTON-WOOL; WADDING ; NON-WOVEN FABRICS FROM STAPLE FIBRES, FILAMENTS OR YARNS, BONDED WITH AT LEAST ONE WEB-LIKE MATERIAL DURING THEIR CONSOLIDATION
  • D04H1/00—Non-woven fabrics formed wholly or mainly of staple fibres or like relatively short fibres
  • D04H1/40—Non-woven fabrics formed wholly or mainly of staple fibres or like relatively short fibres from fleeces or layers composed of fibres without existing or potential cohesive properties
  • D04H1/54—Non-woven fabrics formed wholly or mainly of staple fibres or like relatively short fibres from fleeces or layers composed of fibres without existing or potential cohesive properties by welding together the fibres, e.g. by partially melting or dissolving
  • D04H1/558—Non-woven fabrics formed wholly or mainly of staple fibres or like relatively short fibres from fleeces or layers composed of fibres without existing or potential cohesive properties by welding together the fibres, e.g. by partially melting or dissolving in combination with mechanical or physical treatments other than embossing
• • D—TEXTILES; PAPER
  • D04—BRAIDING; LACE-MAKING; KNITTING; TRIMMINGS; NON-WOVEN FABRICS
  • D04H—MAKING TEXTILE FABRICS, e.g. FROM FIBRES OR FILAMENTARY MATERIAL; FABRICS MADE BY SUCH PROCESSES OR APPARATUS, e.g. FELTS, NON-WOVEN FABRICS; COTTON-WOOL; WADDING ; NON-WOVEN FABRICS FROM STAPLE FIBRES, FILAMENTS OR YARNS, BONDED WITH AT LEAST ONE WEB-LIKE MATERIAL DURING THEIR CONSOLIDATION
  • D04H1/00—Non-woven fabrics formed wholly or mainly of staple fibres or like relatively short fibres
  • D04H1/40—Non-woven fabrics formed wholly or mainly of staple fibres or like relatively short fibres from fleeces or layers composed of fibres without existing or potential cohesive properties
  • D04H1/42—Non-woven fabrics formed wholly or mainly of staple fibres or like relatively short fibres from fleeces or layers composed of fibres without existing or potential cohesive properties characterised by the use of certain kinds of fibres insofar as this use has no preponderant influence on the consolidation of the fleece
  • D04H1/4209—Inorganic fibres
  • D04H1/4242—Carbon fibres
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
  • B29C—SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
  • B29C70/00—Shaping composites, i.e. plastics material comprising reinforcements, fillers or preformed parts, e.g. inserts
  • B29C70/04—Shaping composites, i.e. plastics material comprising reinforcements, fillers or preformed parts, e.g. inserts comprising reinforcements only, e.g. self-reinforcing plastics
  • B29C70/06—Fibrous reinforcements only
  • B29C70/08—Fibrous reinforcements only comprising combinations of different forms of fibrous reinforcements incorporated in matrix material, forming one or more layers, and with or without non-reinforced layers
  • B29C70/081—Combinations of fibres of continuous or substantial length and short fibres
• • D—TEXTILES; PAPER
  • D04—BRAIDING; LACE-MAKING; KNITTING; TRIMMINGS; NON-WOVEN FABRICS
  • D04H—MAKING TEXTILE FABRICS, e.g. FROM FIBRES OR FILAMENTARY MATERIAL; FABRICS MADE BY SUCH PROCESSES OR APPARATUS, e.g. FELTS, NON-WOVEN FABRICS; COTTON-WOOL; WADDING ; NON-WOVEN FABRICS FROM STAPLE FIBRES, FILAMENTS OR YARNS, BONDED WITH AT LEAST ONE WEB-LIKE MATERIAL DURING THEIR CONSOLIDATION
  • D04H1/00—Non-woven fabrics formed wholly or mainly of staple fibres or like relatively short fibres
  • D04H1/40—Non-woven fabrics formed wholly or mainly of staple fibres or like relatively short fibres from fleeces or layers composed of fibres without existing or potential cohesive properties
  • D04H1/42—Non-woven fabrics formed wholly or mainly of staple fibres or like relatively short fibres from fleeces or layers composed of fibres without existing or potential cohesive properties characterised by the use of certain kinds of fibres insofar as this use has no preponderant influence on the consolidation of the fleece
  • D04H1/4274—Rags; Fabric scraps
• • D—TEXTILES; PAPER
  • D04—BRAIDING; LACE-MAKING; KNITTING; TRIMMINGS; NON-WOVEN FABRICS
  • D04H—MAKING TEXTILE FABRICS, e.g. FROM FIBRES OR FILAMENTARY MATERIAL; FABRICS MADE BY SUCH PROCESSES OR APPARATUS, e.g. FELTS, NON-WOVEN FABRICS; COTTON-WOOL; WADDING ; NON-WOVEN FABRICS FROM STAPLE FIBRES, FILAMENTS OR YARNS, BONDED WITH AT LEAST ONE WEB-LIKE MATERIAL DURING THEIR CONSOLIDATION
  • D04H1/00—Non-woven fabrics formed wholly or mainly of staple fibres or like relatively short fibres
  • D04H1/40—Non-woven fabrics formed wholly or mainly of staple fibres or like relatively short fibres from fleeces or layers composed of fibres without existing or potential cohesive properties
  • D04H1/42—Non-woven fabrics formed wholly or mainly of staple fibres or like relatively short fibres from fleeces or layers composed of fibres without existing or potential cohesive properties characterised by the use of certain kinds of fibres insofar as this use has no preponderant influence on the consolidation of the fleece
  • D04H1/4282—Addition polymers
• • D—TEXTILES; PAPER
  • D04—BRAIDING; LACE-MAKING; KNITTING; TRIMMINGS; NON-WOVEN FABRICS
  • D04H—MAKING TEXTILE FABRICS, e.g. FROM FIBRES OR FILAMENTARY MATERIAL; FABRICS MADE BY SUCH PROCESSES OR APPARATUS, e.g. FELTS, NON-WOVEN FABRICS; COTTON-WOOL; WADDING ; NON-WOVEN FABRICS FROM STAPLE FIBRES, FILAMENTS OR YARNS, BONDED WITH AT LEAST ONE WEB-LIKE MATERIAL DURING THEIR CONSOLIDATION
  • D04H1/00—Non-woven fabrics formed wholly or mainly of staple fibres or like relatively short fibres
  • D04H1/70—Non-woven fabrics formed wholly or mainly of staple fibres or like relatively short fibres characterised by the method of forming fleeces or layers, e.g. reorientation of fibres
  • D04H1/72—Non-woven fabrics formed wholly or mainly of staple fibres or like relatively short fibres characterised by the method of forming fleeces or layers, e.g. reorientation of fibres the fibres being randomly arranged
  • D04H1/732—Non-woven fabrics formed wholly or mainly of staple fibres or like relatively short fibres characterised by the method of forming fleeces or layers, e.g. reorientation of fibres the fibres being randomly arranged by fluid current, e.g. air-lay
• • D—TEXTILES; PAPER
  • D10—INDEXING SCHEME ASSOCIATED WITH SUBLASSES OF SECTION D, RELATING TO TEXTILES
  • D10B—INDEXING SCHEME ASSOCIATED WITH SUBLASSES OF SECTION D, RELATING TO TEXTILES
  • D10B2101/00—Inorganic fibres
  • D10B2101/10—Inorganic fibres based on non-oxides other than metals
  • D10B2101/12—Carbon; Pitch
• • D—TEXTILES; PAPER
  • D10—INDEXING SCHEME ASSOCIATED WITH SUBLASSES OF SECTION D, RELATING TO TEXTILES
  • D10B—INDEXING SCHEME ASSOCIATED WITH SUBLASSES OF SECTION D, RELATING TO TEXTILES
  • D10B2401/00—Physical properties
  • D10B2401/10—Physical properties porous
• • D—TEXTILES; PAPER
  • D10—INDEXING SCHEME ASSOCIATED WITH SUBLASSES OF SECTION D, RELATING TO TEXTILES
  • D10B—INDEXING SCHEME ASSOCIATED WITH SUBLASSES OF SECTION D, RELATING TO TEXTILES
  • D10B2505/00—Industrial
  • D10B2505/02—Reinforcing materials; Prepregs
• • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
  • Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
  • Y10T—TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
  • Y10T442/00—Fabric [woven, knitted, or nonwoven textile or cloth, etc.]
  • Y10T442/60—Nonwoven fabric [i.e., nonwoven strand or fiber material]
  • Y10T442/69—Autogenously bonded nonwoven fabric

Definitions

• the present invention relates to a fiber-based carrier structure containing proportions of industrially produced reinforcing fiber materials, containing finite fibers in a random arrangement as a first reinforcing fiber component and containing finite fiber bundles as a second reinforcing fiber component, wherein the fiber-based carrier structure further has a pore system.
• WO 2010/139077 A1 describes a method for producing a composite material having the features of the generic type mentioned at the outset. It contains a core layer that contains at least 20 vol. % air voids and is made of a thermoplastic reinforced with randomly oriented fibers, and reinforcement strips made of continuous, parallel, unidirectional reinforcement fibers, which are embossed into the surface of the core layer on one side or on both sides.
• the reinforcement fibers of the outer layer are thermally fused onto the core layer by thermoplastic binders. It is not clear how the air void content in the core layer could purposively be adjusted, or whether the voids are accessible from the outside at all. There is high product anisotropy between the core and the outer layer.
• the reinforcement fiber strips embossed into the surface of the core layer are oriented so as to be parallel to one another.
• This document relates to producing a composite material having high strength and stiffness, which has good sound absorption.
• the voids have no significance for the absorption of liquids or solid particles, that is to say impregnability is not sought.
• nonwovens are referred to which are characterized in that they consist of fibers whose position can be described only by methods of statistics. Nonwovens are distinguished by the fiber material (for example the polymer in the case of chemical fibers), the bonding method, the type of fiber (staple or continuous fibers), the fineness of the fibers and the orientation of the fibers.
• the fibers can thereby be laid specifically in a preferential direction or can be oriented entirely at random, as in the case of a random-layer nonwoven or random nonwoven.
• a nonwoven having defined proportions of fiber bundles and single fibers as a carrier structure for substances and the use thereof in the field of fiber composites is hitherto unknown.
• nonwovens which can be bonded mechanically, thermally or chemically, have, depending on the fiber material, fiber geometry (thickness, length), fiber material mixture and production or consolidation, demonstrable properties for binding liquids or solid particles in the form of powders.
• a specific absorption capacity is referred to, which manifests itself in the absorption of more or less large amounts of liquids—which in most cases are aqueous, low-viscosity systems for applications in the field of cleaning or soaking up within the meaning of disposal—in a nonwoven into the inner layers thereof. Viscous liquids or melts can only be absorbed at the surface of the nonwoven without additional measures.
• the object of the present invention is to define a fiber-based carrier structure having the features mentioned at the outset, produced, for example, from loose fiber fillings of randomly arranged/oriented finite fiber materials, which, when shaped in a mat-like manner or three-dimensionally as a reinforcing fiber pre-product, exhibits a high and controllable impregnability with viscous liquids and powders and at the same time is able to retain large amounts of these substances in the inside in a uniformly distributed manner.
• the invention provides a fiber-based carrier structure for producing fiber-reinforced composite materials which, through the use of a defined mixture of finite randomly arranged fiber bundles and finite randomly arranged single fibers, is particularly suitable for absorbing liquids, melts and/or solid particles.
• the impregnability and the absorption capacity for liquid, also viscous, and/or solid pulverulent substances can be adjusted via the mixing ratio of fiber bundles:single fibers.
• the fiber carrier structure has a uniform structure in terms of length, width and thickness and is distinguished by an open-cell pore system that is openly accessible from the outside.
• the fiber carrier structure according to the invention does not consist of at least two different product zones of different compositions and orientations, as described in international patent disclosure WO 2012/072405 A1, or of a core and a cover layer of continuous fibers having a completely different structure, as described in international patent disclosure WO 2010/139077.
• the finite fiber bundles in the present invention preferably result from reinforcing fiber bundle pieces or multifilament yarn pieces which were originally continuous but have been reduced to finite lengths, in which the single fibers adhere to one another in parallel in a mechanically detachable manner over at least 50% of the length thereof by non-natural binding means.
• They can, however, also be fiber materials from recycling processes, if these are obtained in the form of bundles within the meaning of this invention.
• fiber bundles in the fiber bundle which adhere to one another in parallel and in a mechanically detachable manner are substantially different from the fiber bundles mentioned in the literature, for example in the case of the intermeshing or needling of nonwovens, which are formed from single, isolated fibers over only a short length ⁇ 50% of the fiber lengths, for example when random fibers are brought together in an intermeshing hook or in the barbed hook in the case of needling.
• the fiber bundles described in the literature are held together only locally by external pressing forces or binding points. They form only during textile processing and are also referred to in the specialist literature as mechanical consolidation points, whereas the fiber bundles in the described invention are already present in the starting material, the fiber material, and are not formed purposively during the processing operation.
• the single fibers used in the mixture that is employed can consist of the same or a different polymer as the fiber bundles that are used.
• This special carrier structure formed of the two fiber systems, fiber bundles and single fibers, in defined uniform or different thickness and/or mass per unit area is stabilized mechanically, thermally and/or chemically and fixed in such a way that at least 10 and not more than 90% of the resulting, consolidated fiber carrier consists of fiber bundles having a minimum number of 10 single fibers that adhere to one another in parallel, and an open-cell pore system that is openly accessible over the entire structure is formed.
• the pore system contains a plurality of interconnected voids, which are interconnected by transport channels in order to be able to transport powders and/or liquids applied from the outside into the voids.
• the proportion of fiber bundles used thereby determines to a significant degree the impregnability or the depth of penetration of highly viscous and pulverulent substances into the product layer.
• the proportion of single fibers thereby determines to a significant degree the penetrability of storable liquids or powders.
• the voids are thereby interconnected by transport channels in order to be able to transport powders and/or liquids or melts applied from the outside into the voids.
• this effect is purposively developed and controlled via a purposively adjustable mixture of the two components. Therefore, in the case of the product according to the invention, defined proportions of finite fiber materials of the same or different types are processed in two forms, a bundle-like, non-unraveled form and a single-fiber form, in such a manner that, in a nonwoven-like mat or a three-dimensional molding, at least 10% but not more than 90% of the fibers used still remain in the form of non-unraveled bundles, and the further usability as a fiber pre-product for reinforcing plastics materials is thereby significantly determined.
• the fiber bundles and the single fibers are in a random arrangement without a defined orientation, as is achieved, for example, by a random loose filling material.
• Such mixtures can be produced in a defined manner on the one hand by gravimetric weighing of one or more fiber components in bundle form with one or more single-fiber fiber components and subsequent mixing, for example by a textile mixing technique.
• a textile mixing technique for example by a textile mixing technique.
• the opening technique, number of passes and parameters to be used in conjunction with the nature of the starting material in fiber-bundle form are to be adapted to one another in test series in such a way that the desired residual proportion of bundles in the product is obtained.
• the main influencing parameters in the starting material are the fiber bundle length and the intensity with which the single fibers adhere in the fiber bundles that are provided.
• the mechanically detachable parallel adhesion of the single fibers over a length >50% of the single fiber length in the bundles is significantly determined by the nature and amount of substances having an adhesive action that are foreign to fiber polymers and are found on the fiber surface, such as sizes and finishes.
• Uncross-linked and/or uncured polymers can also be used as binders in the bundles. The important criterion is that it must be relatively easy to separate the bundles mechanically.
• the fiber bundles are characterized in such a way that they consist of at least 10 mutually adhering parallel single fibers which adhere to one another over at least 50% of the length thereof.
• the fiber bundles can be mechanically separated into smaller bundles or single fibers relatively easily and without damaging the fibers.
• This mixture of fiber bundles and single fibers having a defined proportion of fiber bundles and single fibers that remains constant over the production time leads to a defined thickness and mass per unit area profile, it being possible for both the thickness and the mass per unit area to be developed uniformly or purposively differently over time and area during the formation of the loose fiber filling.
• Conventional fiber-processing units of the textiles field can be used for the production and processing of this fiber mixture of bundle-like and single-fiber components, but such units must be modified technically and technologically in such a way that the desired mixing ratio of bundle-like components and individual fibers is ensured.
• Such modifications include reducing the number of fiber-opening passes, dispensing with carding and roller carding in the processing operation, reducing opening roller speeds, using coarser roller coverings during mixing, homogenization and metering, and increasing the distances between operating units having an unraveling action.
• Suitable units for laying the loose fiber layer of bundle-like and unraveled components are in principle mechanically and/or pneumatically operating units, such as filling hoppers, airlay or fiber-blowing systems.
• systems and methods must in particular be configured, via the above-mentioned measures, in such a way that, on the one hand, they act to homogenize the mixture and, on the other hand, the fiber-opening effect brought about by their fiber-opening/unraveling intensity is defined and only such that the desired target range of fiber bundle proportion and single fiber proportion is reached. If fiber-opening units are used to a certain degree, the unraveling action of those units must be taken into account through a higher proportion of fiber bundles in the starting material that is provided. This mixture of fiber bundles and single fibers is laid randomly.
• pulverulent substances thermally binding components or liquid binders that are not originally a constituent of the fibers and/or fiber bundles used can be introduced at the same time.
• binding components are used to fix the pore system and the carrier structure of single fibers and fiber bundles and/or as a binding component in the formation of the fiber-reinforced composite materials.
• mechanical methods such as needling or intermeshing or binder consolidations of loose layers containing binders or thermoplastics.
• the action of contact or radiation heat or the passage of hot air has a melting action or dry liquid binder components.
• the application of binders for fixing the pore system and the carrier structure of single fibers and fiber bundles and/or as a binding component in the formation of the fiber-reinforced composite materials after the formation of the loose layer in the form of powder application or spraying is likewise technically possible and is determined by the intended use of the consolidated layer.
• consolidation is generally carried out by a heat treatment that dries the binder or that effects melting or the start of melting.
• the open pore system of the nonwoven-like pre-product consists of small voids, which form in particular as gaps between the random, intersecting single fibers of very small diameter, and larger voids, which form as gaps between the random intersecting fiber bundles of substantially larger diameter.
• small voids which form in particular as gaps between the random, intersecting single fibers of very small diameter
• larger voids which form as gaps between the random intersecting fiber bundles of substantially larger diameter.
• these pores or voids which are purposively adjustable according to the proportions of single fibers and fiber bundles, perform the function of binder transport, or binder infiltration of the nonwoven pre-product and of fixing the binder in the nonwoven pre-product.
• the coarser, open pore system forms transport channels for thick, viscous binding resins and powders, which channels extend into the center of the nonwoven layer. It is thus possible to substantially assist with a desired complete, continuous impregnation with viscous liquids and powders, which simplifies impregnation technology in terms of costs and technology, shortens impregnation times and makes it possible to use thicker reinforcing fiber pre-products.
• the finer pores based on the single fibers in the product ensure that the binder components that have penetrated are retained and incorporated in the product in the manner of a sponge.
• the proportion of fine and coarse pores is determined by the respective proportions of coarse fiber bundles and fine single fibers in the nonwoven.
• the impregnating medium to be used to form the consolidated carrier structure or the fiber-reinforced molding and the infiltration technology the proportions of fiber bundles and single fibers are to be tested and specified in preliminary tests for the fiber material to be used in each particular case.
• vertical puncture channels can be formed in addition to the existing pore structure, which channels assist with the transport of binder into the nonwoven layer and influence the function of the impregnability.
• the penetrability of the nonwoven is generally reduced and the depot action is reduced.
• the impregnability that is produced is again purposively influenced and fixed in terms of the final quality and quantity thereof.
• fiber materials used reside in the field of conventional reinforcing fiber materials.
• They can be organic fiber materials such as para-aramids as well as glass and carbon fiber materials including fiber materials of this type from various recycling processes.
• the proportion of fiber bundles, based on mass, was determined by manual screening, the air through-flow resistance was determined by an air through-flow method as a measure of the open-pore nature and accessibility to particles and liquids, and the drop sink-in time was determined by means of a drop test using a more highly viscous liquid in accordance with the TEGE-WA drop test as a measure of the impregnability.
• the proportion of fiber bundles was determined by manual screening of a fiber sample of 1 g, weighing the bundle components from at least 10 single fibers and calculating the proportion by mass in percent.
• the amount of air that flows per unit time the dimensions of the measuring chamber (diameter, height), the viscosity of the flowing medium, the porosity of the fibers, and the fiber surface area.
• the porosity of a fiber pad was determined by this air through-flow method.
• the fiber pad is in this case the test specimen, formed from the carrier structure produced according to the example. All the parameters apart from the fiber material to be tested were kept constant.
• the air resistance generated by the fiber pad is read off from the measuring instrument in [mm] of an isopropanol liquid column.
• the column height in [mm] is directly proportional to the air through-flow resistance that is established and thus indirectly proportional to the porosity.
• the tests were in each case carried out on 1.4 g of fiber material at an air through-flow speed of 400 l/min.
• a CMC solution having a viscosity (25° ° C.) at a shear gradient of 2/s of 1.7 Pas was used as the test liquid.
• the mass of the test drop was 0.5 g in all cases.
• the starting material was intimately mixed with 7% of a thermally softening binding fiber GRILON MS 6.7 dtex/Vario bain via a mixing bed and 1 mixing pass by means of a coarse opener using a mixing/opening pin roller and supply of the material via a roller pair.
• Half of this constant starting fiber mixture of recycled carbon fibers having a high proportion of fiber bundles and thermally softening binding fibers in a mixing ratio of 93/7 was then laid via an FBK 536 feeder from Tru ⁇ umlaut over (t) ⁇ zschler at 2 m/min to form a loose filling of 370 g/m 2 .
• the other half of the starting material was processed as comparative material by carding twice with a roller card using three worker/stripper pairs at 10 m/min to form card web and placed in loose layers one above the other by means of crossplaiters so that a mass per unit area of 370 g/m 2 was obtained.
• the proportion of single fibers is comparatively high in the case of the nonwoven mat laid by carding machine that was used as comparative material (on the right in the above table) (ratio proportion of single fibers to fiber bundles approximately 14.15:1).
• the above table shows that the water absorption is substantially higher in the case of the carrier material according to the invention than in the case of the comparative material.

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• Engineering & Computer Science (AREA)
• Textile Engineering (AREA)
• Chemical & Material Sciences (AREA)
• Mechanical Engineering (AREA)
• Inorganic Chemistry (AREA)
• Composite Materials (AREA)
• Nonwoven Fabrics (AREA)
• Yarns And Mechanical Finishing Of Yarns Or Ropes (AREA)

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• 2014
  • 2014-02-19 EP EP14705188.2A patent/EP2959044A1/fr not_active Withdrawn
  • 2014-02-19 JP JP2015558431A patent/JP2016510091A/ja active Pending
  • 2014-02-19 CA CA2900996A patent/CA2900996A1/fr not_active Abandoned
  • 2014-02-19 KR KR1020157025436A patent/KR20150120445A/ko active Search and Examination
  • 2014-02-19 WO PCT/EP2014/053201 patent/WO2014128149A1/fr active Application Filing
  • 2014-02-19 CN CN201480009795.0A patent/CN105339540A/zh active Pending
  • 2014-02-19 DE DE102014102079.0A patent/DE102014102079A1/de not_active Withdrawn
• 2015
  • 2015-08-20 US US14/830,944 patent/US20150354111A1/en not_active Abandoned
• 2016
  • 2016-03-24 HK HK16103492.9A patent/HK1215597A1/zh unknown

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