DE2166320A1 - Multilayer laminated fibrous structure - two unopened film fibre structures with lengthwise fibrillations are laminated, dr - Google Patents

Abstract

The laminated structures are drawn widthwise to open their fibre structure, and pressed at a temp below their melting pts. to bond them. Prior to pressing, they may be laid on a further film material, which may be a non-opened or opened fibrillated film or paper or woven or knitted fabric etc. The prod. can be used as a substitute for paper, or for electrical insulation etc.

Description

Process for the production of multilayer, fibrous composite structures The invention relates to a method of making multilayer, fibrous composite structures.

When manufacturing fibrous composite structures from individual, foil-shaped fiber structures, the main focus is to be directed to that the fibers of the individual, film-shaped fiber structures are intimately intertwined to create a physically uniform and durable fibrous composite structure to achieve.

The object on which the invention is based was a method to create multilayer, fibrous composite structures with which in an extremely simple and effective way the fibers of the individual foil-shaped Fiber structures can be intimately intertwined.

This is achieved according to the invention in that at least two fibrillated, unopened, film-shaped fiber structures with numerous discontinuous parallel cracks in the direction of their cracks to be placed on top of each other to form a laminate and the laminate transversely to the direction of the Cracks drawn and opened and at a temperature below the softening point of the material used for the fiber structures is pressed.

Since in the inventive method for producing multilayer fibrous composite structures which are laid on top of one another to form a laminate, not opened, film-shaped fiber structures pulled apart together transversely to the direction of the cracks and opened, a physically uniform, networked composite structure can be created achieve in which the contact area and the intimate interweaving between the Fibers of the used th film-shaped fiber structures is very high. Through the Compression of the opened laminate becomes the interweaving of the layered one on top of the other film-shaped fiber structures fixed, so that nonwoven fabrics with a high Strength both in the longitudinal and in the transverse direction of the cracks arise.

The fibrillated, unopened, film-shaped fiber structures, used in the manufacture of multilayer fibrous composite structures, can be produced in a variety of ways. For example, there is one procedure known for the production of unopened, crosslinked fiber structures, in which a mixture of a fiber-forming, molten polymer and a foaming agent extruded into a film and the extrudate over a longer distance on one side the temperature lying at the glass transition point and fibrillated by stretching will. In this known process, foam formation in the extrudate takes place after it Exit from the extrusion nozzle steadily. This increasing foaming is the cause ensure that the extrudate tears when stretched. It therefore arises a networked fiber structure that has very large meshes and knots. With This known method can be produced crosslinked fiber structures therefore have no flexibility or softness.

The fibrillated, unopened, crosslinked fiber structures can be used without difficulty for the method according to the invention can be used to make multilayer fibrous composite structures. It however, much better results are achieved if unopened, crosslinked Fiber structures are used, which according to a parallel application of the Process described by the applicant, by which unopened, networked fiber structures with very narrow ashes and small knots can be achieved can. The very tight stitches and small knots make them very soft and flexible unopened, networked fiber structures, so that the further processing of the fiber structures much simplified and a composite structure with a much wider range of applications is achieved.

In the last-mentioned process for the production of unopened, crosslinked fiber structures is a mixture of a fiber-forming, melted Polymer and a foaming agent are extruded into a film and the extrudate fibrillated by stretching, with the extrudate in close proximity to the extrusion die is quenched to a temperature below the glass transition point, and stretching the quenched extrudate at a stretch ratio that is between the maximum possible stretch ratio and a third of the maximum possible stretch ratio lies.

According to a modification of this process for the production of unopened, cross-linked fiber structures, the extrudate can be blown with cooling air and quenched to a temperature that is at least 50 C below the glass transition point of the polymer lies.

The unopened, unopened, Foil-shaped fiber structures show numerous discontinuous cracks or splits along the stretching direction, being extremely fine and numerous parallel ones Fibers are created that are very close to each other and are networked Form structure. This means that the structures are not opened into fibers. In which process according to the invention for producing multilayer fibrous composite structures are advantageously at least two of the above-described unopened, film-shaped and cross-linked fiber structures placed one on top of the other to form a laminate, the directions of the cracks in the fiber structures coinciding. Then it will be the laminate is pulled and stretched across the direction of the cracks. Be that way the foils laid one on top of the other to form a laminate are opened and physically uniform, networked structures transferred, creating the contact area and the interweaving between the foils is noticeably increased. The opened laminate is pressed together to to fix the interweaving between the foils and nonwoven fabrics with a high strength manufacture, not only in the direction of the cracks, but also is present across the cracks. The film-shaped Fiber structures can be opened using equipment that is usually used for the elongation or stretching of synthetic resin films can be used, for example by means of a pin or clamp frame device.

The focal ratio varies depending on the one intended for the product Intended use, but usually it is chosen to be 3 to 15 times amounts to.

The opened laminate must be at a temperature below the softening point of the material used for the film-shaped fiber structures will. When the pressure is applied at a temperature above the softening point the fiber content is noticeably flattened. In extreme cases, the product can be converted into a film, so that no favorable film-shaped structures develop. The laminate can be made in the usual way, for example by calender rolls, Press plates, etc., are pressed together. It is also possible to use an embossing roller or use an embossing plate æu to emboss the products with a pattern.

The pressure exerted when squeezing is variable and depends on various factors, such as the density of the film-shaped structures, the number the superimposed, open fiber structures and the opening ratio etc., from. The optimal pressure can easily be determined empirically, it is usually between 4o and 60 kp / cm2.

That from the opened, film-shaped, cross-linked fiber structures existing laminate can be foil-shaped before pressing on one, two or more other Structures are applied that are, for example, opened or unopened, film-shaped and cross-linked fiber materials with numerous discontinuous can be cracks running in one direction. The other film-shaped structures can be made from the same or a different polymer as the opened structures of the laminate. The one from the open Laminate and the other Laminated bodies consisting of film-shaped structures are then kept at one temperature below the softening point of the polymer with the lowest softening point put under pressure.

In this way, composite structures can be created with even greater strength can be obtained in both the longitudinal and transverse directions. In particular the laminate by laying the opened laminate on top of one another and an unopened, film-like and cross-linked fiber structure is obtained, has the striped surface pattern, which is formed by fibers that, like wood fibers, run in one direction. In this way, a composite structure can be created by embossing such a laminated body obtained with the look and feel similar to that of wood, without the need for printing.

The type of unopened, film-shaped and cross-linked fiber structures, the number of foils to be laminated, the aperture ratio, the amount of pressure and so on, can according to the intended use of the product be chosen appropriately.

The unopened, film-shaped and cross-linked fiber structures, which are superimposed to form the laminate; can with a pigment or dye colored. If the foil materials contain at least two are colored in different colors, the resulting laminate will have a pattern complex mixed colors granted. In the same way, they can form the laminate opened film materials and the other applied film materials different Have colors. When the laminated body thus formed from the open Laminate and the other sheet materials are further subjected to an embossing treatment the impressed parts can be pressed together to film thickness during the embossing so that the color of the underlying layer shows through. So can that Product can be given a multicolor sample without the need for printing is.

It is also possible to have at least two unopened, film-shaped and cross-linked fiber structures in the direction of their cracks, to form a laminate one on top of the other to lay, pull the laminate perpendicular to the direction of the cracks to its opening to effect another unopened or opened laminate on the opened laminate Laying sheet material with a reinforcement layer or layers and to compress the resulting layered body, so that a uniform one and reinforced composite ornamental structure with improved physical properties arises. The reinforcement material can be on one side of the laminate or between the layers forming the laminate are laid.

For example, papers such as handmade paper, Asbestos paper and synthetic paper, woven or knitted goods, non-woven Fabrics, fleece, such as glass mats, and non-woven fabrics as natural, semi-synthetic and synthetic fibers, films such as synthetic resin films, metal foils and films made of regenerated cellulose, foamed foils, sheet-like materials, such as.

Corrugated cardboard, wood, plywood, hardboard, asbestos and metal sheets and the like., can be used.

By suitable selection of the respective reinforcement layer can physical properties favorable to the composite structures, such as good strength, Flame resistance, thermal insulation, sound absorption, water tightness, etc., granted The composite structures obtained in this way can, if desired, be coated with transparent Surface protective layers such as those made of cellophane, synthetic resin films and resinous coating materials. So can the composite structures surface strength, wax resistance and the property of prevention the deaf formation, etc. are awarded.

The following are the main layer combinations of the laminate shown. For this purpose, the superimposed, open, film-shaped fiber structures existing laminate with (A), while the other film-shaped, crosslinked fiber structurally, which is opened or can not be opened, with () and the reinforcement layer with (C) become: 1. (A) alone 2. (nu + (B); (A) + (C) 3. (C) + (A) + (B); (n) + (c) + (B) ( A) + (3) + CA) ;. (B) + (A) + (B) 4. (B) + (A) + (C) + CA); (B) + (A) + (c) + (B) 5. (B) + CA) + (c) + (A) + (B) The laminated body consisting of the individual layers can, if desired, be impregnated with a binding agent before pressing, to improve the strength and adhesion and cohesion of the end products. As the binder, any of the commonly used agents can be used such as a Vinyl acetate emulsion, a vinyl chloride emulsion, an acrylic emulsion, an NBR latex and SBR latex, etc.

An exemplary embodiment of the method according to the invention is described below explained in more detail with reference to drawings. In the drawings: FIG. 1 shows a schematic Side view of a device for producing composite structures according to the invention Method FIG. 2 is a schematic plan view of a device for opening the unopened laminates consisting of film-shaped and cross-linked fiber structures.

Fig. 3 is an enlarged photograph of a conventional method produced unopened, film-shaped and crosslinked fiber structure; Fig. 4 is an enlarged photograph of an unopened, film-shaped and reticulated Fiber structure made by a method described in a parallel application by the applicant.

Fig. 5 is an enlarged photograph of an opened, made of foil-shaped and crosslinked fiber structures existing laminates In Figs. 1 and 2 is the Manufacture of a composite structure according to the invention explained. Two lanes 11 and 11 'made of unopened, film-shaped and crosslinked Fiber structures are withdrawn from supply rolls and a first pair of rollers 12 and a second Roller pair 13 supplied. Although according to the embodiment of FIG. 1 only two Lanes 11 and 11 'are provided, more than two lanes, if desired be used. All that is needed is the appropriate number of supply rolls to be provided. The webs 11 and 11 'can be fed to the Y-roll pairs 12 and 13 are colored the same or different. The by the roller pairs 12 and 13 superimposed, unopened foils will wipe the second pair of rollers 13 and the pressure rollers 15 pulled apart transversely to the conveying direction and opened. The opening of the superimposed fiber structures can be through a web holder 21 can be achieved between the second pair of rollers 13 and the pressure rollers 15 is attached and which extends from the second pair of rollers to the folds in a fan shape opens.

In the embodiment shown in Fig. 1, the ratio corresponds LoJBi the opening ratio, which according to the invention is preferably between 3 and 15 lies.

An enlarged photograr.lie of the opened, foil-shaped and crosslinked laminate is shown in FIG.

Those consisting of superimposed, open fiber structures Web 14 is optionally provided with other fiber structures and / or a reinforcing layer 20, for example a film or foamed sheet, covered before the binding pressure is subjected. Then the laminate is made of laminate and other fiber structure guided by the pressure rollers 15. The uniform sheet-shaped laminated in this way Laminated body is optionally placed in an impregnation container with a binder introduced, in a drying device 17 dried and then pressed together and connected by the pressure rollers 18, so that a composite structure 19 is created. The pressure rollers 18 can be a conventional calender roller, which delivers products with a smooth surface. If 18 preseeding rollers are used as printing rollers Can be used with different patterns, ornamental composite structures can be obtained with a relief-like pattern. The thus obtained, inventive mässen composite structures have excellent physical properties, for example excellent mechanical strength and flexibility. The invention manufactured composite structures are suitable for a wide variety of uses, for example for synthetic paper, for wallpaper, for decorative paper, interior decoration materials, such as 3. Ceiling panels and ornamental veneer panels, various building materials, Filters, nonwoven fabrics, electrical insulators, packaging materials and the like

For the method according to the invention, open, film-shaped networked fiber structures of all kinds are used. For example, unopened Films of the type shown in Fig. 3 have been used, the result of conventional Manufacturing processes are.

In the case of the films of the type shown in FIG. 3, the individual sags the discontinuous cracks resulting from fibers or threads are relatively wide apart, resulting in large stitches and thick knots. These big ones Meshes and thick knots reduce the softness and flexibility of this film-shaped, networked structures, so that ultimately composite structures result that have a small area of application and, for example, do not serve as a substitute for paper can serve.

The composite structures produced by the method according to the invention However, they have great softness and flexibility and thus a wide range of applications, if the soles shown in FIG. 4 are unopened for the production of the laminate Kind be used following a procedure described in a parallel application of the applicant. In the unopened, crosslinked shown in FIG Foils, the fibers and threads created by the cracks lie close to each other, whereby the stitches and knots become small and the softness and flexibility large. It goes without saying that the photographs of the foils placed opposite one another 3 and 4 represent the same enlargement.

In the following, eie invention is based on implementation examples explained in more detail.

Example 1 There became a sample A and a sample B of a laminate produced, whereby of unopened, film-shaped fiber structures of the in Fig. 4 has been passed. The unopened, however, film-shaped fiber structures had different physical data than that Fiber structures of sample B, as can be seen from Table I below.

In both cases, several unopened, film-shaped fiber structures were found of the same species superimposed under the conditions given in Table I, opened, immersed in a vinyl acetate emulsion (uptake 30%) and pressed together, the results given in Table I were obtained. In this table means "tensile strength (parallel) and (at right angles)" T a b e l l e I properties of the film-shaped and cross-linked fiber structures the lamination tensile strength + (kg / cm²) number of the thickness weight in the right laminated Type of elongation (µ) (g / m²) parallel angle foils lamination direction sample A 25 3.5 0.56 almost zero 240 in the direction perpendicular to the crack direction of the cracks Sample B 50 6.8 0.30 almost zero 50 in the direction perpendicular to the direction of the cracks Cracks + The tensile strength was measured according to JIS P-8113 (zipper interval 20 mm, Pulling speed 20 mm / minute) Properties of the laminate obtained Opening tensile strength (kg / cm2) ratio of compression to thickness weight in the right (x-fold) conditions (p) (g / m²) parallel Minkel sample A 10 50 kg / cm² 250 110 100 75 70 ° C, 1 min.

Sample B 3.5 50 kg / cm² 240 100 95 70 80 ° C, 1 min.

the particular tensile strength obtained by pulling the product towards the cracks and across the cracks were determined.

As can be seen from Table I above, laminatenit excellent tensile strengths both in the longitudinal direction and in the transverse direction can be achieved when the film-shaped structures according to the inventive method laminated, opened and pressed together. The resulting laminates represent a very valuable substitute for paper.

Example 2 A molten polymer of polystyrene, the one Containing foaming substance was made from a nozzle with a slit of one size Extruded from place 35mm x 150mm. At the nozzle outlet air was at a temperature of not more than 20 ° C against the extruded, molten polymer above it Blown full width to cool the extrudate, in this way the extrudate was quenched from 260 to 600 C. The extrudate was then stretched with a stretching device ratio of 120 stretched.

The resulting structure showed numerous discontinuous cracks which ran in one direction (corresponding to the direction of stretching), wherein the spaces between the cracks became fibrous.

The product had the properties given in Table II below.

Table II Properties of the sheet-like crosslinked structure Tensile strength fig / a) Composition foaming-stretching-thickness weight corresponding to the polymer Substance Kungsver- (µ) (g / m²) ralel angle ratio Polystyrene 99% nitrogen gas 120 25 3.5 0.50 almost talc 1% zero The sheet-like obtained in this way Structures were laminated under the conditions given in Table III, stretched and open. The opened laminate was also pointed in the direction of the cracks placed on the unopened film-shaped structures obtained above. The laminated body made of opened laminate and superimposed, unopened film-shaped Structures were impregnated with a binder (vinyl acetate emulsion, absorption 25%), dried and pressed together.

In this way, a paper-like composite structure with a Surface pattern with fine longitudinal stripes like wood fibers obtain.

If the composite structure has been shaped so that the direction of the Surface cracks coincided with the direction of the fiber axis of the grain was get a paper-like composite structure that resembles wood. The physical Properties of this structure are also given in Table III below.

Table III Unopened openers laminated to the opened laminate Laminate te film-shaped structures Properties of the end product Tensile strength Number of openings Number of openings together (kg / cm²) the ratio of the ratio press in the right thickness weight foils (x-fold) foils (x-fold) conditions parallel Angle (µ) (g / m²) 250 10 4 0 50 kg / cm² 150 70 200 110 80 ° C 5 minutes example 3 The dyed, unopened, film-like and cross-linked fiber structures with the properties given in Table II were laminated, opened, in a liquid binder (vinyl acetate emulsion, absorption 25%) immersed, dried and with embossing rollers under the conditions given in Table IV below pressed.

The resulting composite structure had a surface pattern in which the raised parts were brown and the recessed parts as thin as were a film, so that the underlying black color through achia. The properties the end product obtained are given in Table IV below. Tabel IV opened laminate Properties of the end product Number of foils Opening Pressing conditions Tensile strength (kg / cm²) Upper layer: Back layer withstands pressure Temp. Time in the right thickness Weight brown black nis (x-fold) (kg / cm²) (° C) (min.) parallel angle (µ) (g / m²) 150 50 10 75 90 3 145 75 195 100 example 4 240 foils made from unopened, cross-linked fiber structures with the ones in the table II specified properties were laminated and with an aperture ratio of lo opened Two of these laminates were placed one on top of the other, with a film made of a polycarbonate film (thickness 50/1) was placed in between. This laminate was compressed at 800 C under a pressure of 50 kg / cm2.

So was a reinforced ornament material (decorative material) with a networked structure. This composite structure had a tensile strength of 3.9 kg / cm across the width and a voltage resistance of 9.3 kilovolts.

For comparison, conventional polyethylene sheets were compared to corresponding ones Way laminated on both surfaces of the same polycarbonate film. The product obtained had a tensile strength of 3.1 kg / cm across the width and a voltage resistance of 8.1 kilovolts.

As is clear from the above results, has the composite structure produced according to the invention has a high tensile strength and a exceptionally high voltage resistance (voltage resistance) and is therefore suitable as an insulating material for electric wires, etc.

Example 5 240 sheets of unopened, crosslinked structures with the properties given in Table II were laminated on top of each other, opened with an aperture ratio of 10 and at 80 ° C under a pressure of 40 kg / cm² compressed @ pressed. This created a composite structure with a networked pattern (Weight 100 g / m2).

This was applied to an asbestos plate using a vinyl acetate emulsion attached as a binder and subjected to a flammability test (JIS-A-1321-19; 70). Without the asbestos panel, the composite structure passed the test with nothing Asbestos board, the composite structure passed the test with rating 1 (level 1).

- Expectations -

Claims (1)

FACT SHEET 1. Process for the production of multilayered fibrous Composite structures, characterized in that at least two fibrillated, unopened, film-shaped fiber structures with numerous discontinuous, essentially parallel cracks in the direction of their cracks laid one on top of the other to form a laminate and the laminate is pulled across the direction of the cracks and opened and at a temperature below the softening point of that used for the fiber structures Material is pressed. 2. The method according to claim 1, characterized in that the opened laminate before pressing onto at least one further, film-shaped Material is applied. 3. The method according to any one of claims 1 and 2, characterized in that that as a further film-shaped material optionally an unopened or opened one foil-shaped fiber structure is used. 4. The method according to any one of claims 1 and 2, characterized in that that as a further film-shaped material optionally paper, woven or knitted Goods, non-woven fabrics, a film, a foamed sheet or a plate are used will. 5. The method according to any one of claims 1 to 4, characterized in that that optionally when using more than one further film-shaped material only sheet materials of the same type or sheet materials of different types can be used in alternating layers. 6. The method according to any one of claims 1 to 5, characterized in that that the further sheet-like material is provided with a reinforcing layer will. Method according to claim 6, characterized in that the reinforcement layer optionally on the side of the open laminate facing or facing away further sheet-shaped material is arranged. 8, the method according to any one of claims 1 to 7, characterized in that that consisting of the opened laminate and the further film-shaped material Layered structure is subjected to an embossing treatment before pressing. 9. The method according to any one of claims 1 to 8, characterized in that that the opened laminate and the other film-shaped material with various Colors can be colored. 10. The method according to any one of claims 1 to 8, characterized in, that the unopened film-shaped used to form the opened laminate Fiber structures can be colored with different colors. 11. The method according to any one of claims 1 to lo, characterized in, that consisting of the opened laminate and the further film-shaped material Layer structure is impregnated with a binder before pressing.