DE1704900A1 - Process for the production of laminates - Google Patents

Description

Polymer Processing Research Institute Ltd.

Process for the production of laminates

The invention relates to a method of manufacture multi-layered materials by layering them on top of each other and pressure bonding of two or more layers of molecularly oriented thermoplastic films, prevented by uniaxial or multi-axis stretching of preformed films, either alone, or together with organic or inorganic fibrous Materials or with papers, foils, veneers or metal foils at the softening temperature post-stretched films.

An object of the present invention is to produce multi-layered materials that are extraordinarily have superior physical properties that cannot be achieved by staining a single-layer material of the same thickness without making a

109822/1936 _ßAD original

Layering can get.

Another object of the present invention is to produce multilayer materials that can be used by the Combination of the properties of the layers forming them, such as the tensile strength of the stretched thermoplastic Films and in that other materials such. B. fe fibers, papers, veneers etc. are inserted, have unique properties. In addition to these advantages mentioned, the present invention also has other benefits on.

In the present patent application, “stretching” is to be understood as uniaxial or biaxial stretching, with heating to the softening temperature, following the preforming and consolidation of the film. The high spatial orientation of the molecules in the stretched film depends crucially on the extent of this stretching, which is almost 100 times greater. Pressure than takes place during preforming. The term ¹¹ film "is generally not defined on the basis of its thickness. A rubber sheet that is 1 mm or more thick is referred to as a rubber film.

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spoken of by a plate when the thickness is 0.2mm amounts to. The reason for this is that you are with a A very flexible material, despite its thickness, is called a film, while a thin, but not very flexible material is called a plate. E.g. like a PVG part with a thickness of 0, -5 now, which is very flexible due to the content of a plasticizer, called a film, on the other hand called a plate if it does not contain a plasticizer,

j £ in plastic part referred to as a plate at room temperature becomes more flexible at higher temperatures and can then referred to as film because of its properties will. In the present application, therefore, without taking into account the peck under the film, a wide, thin Plate can be understood.

It is well known that the better orientation of the molecules during post-stretching increases the tensile strength, elongation and other physical properties are significantly improved. Bs is still it is well known that in synthetic fibers the tensile strength per den is lighter in the presence of small numbers of yarns (den) can be enlarged than with larger numbers of yarns, because the tensile strength under the same manufacturing conditions per which becomes smaller with larger numbers of yarns. in the

109822/1936

Viscose process for the production of synthetic fibers, "in which the Post-stretching is carried out directly after the precipitation, the fibers are already stretched, if still Differences in the degree of precipitation of the external and internal Layers exist. This means that the outer layers are more easily subjected to orientation, and so with larger numbers of yarn (den) the achievement of a higher tensile strength as a result of the smaller ratio Surface: volume becomes more difficult. Furthermore, it is well known that even in most methods Manufacture of synthetic fibers in which solidification is completely separated from the post-stretching process and stretching by post-stretching an already solidified product that was subsequently reheated until it softened, is carried out, the g / d ratio of the so produced Fibers with smaller numbers of yarns becomes larger. The reason for this can be given that when stretching fibers between a group of two sets of rollers the rear tension due to the abrasion of the superficial layers of the Fibers are supported with one another and that therefore the increase in the stretching tension caused by the abrasion of the entire fiber to those in the surface. Molecules than takes place on the inner molecules, so that the molecules of the surface are aligned more strongly than the inner molecules, which leads to that the g / d ratio generally with decreasing yarn count

10 9822/1936 -

(den) becomes larger, since the finer fibers have a larger one Have surface.

The same situation applies to the stretching of films before. In many stretching processes, the tensile strength (kg / mm) of the film is greater for the same degree of stretching, when the film thins.

There is no difference here whether the stretching is carried out uniaxially or biaxially / from the above Reasons in the method according to the invention are uniaxial or biaxial post-stretching in the state of a thin film, the surface of which is large in relation to its weight, see above that tensile strength and other physical properties are improved. Many will, at least two or more layers of such films that heated to the softening point in such a way that the aligned molecules retain their orientation have been stacked on top of one another and pressed to form a uniform bond to form a tough product the desired thickness and width. This method is the first feature of the invention. Well that second feature are one or more layers of the layered and glued film again with fibers, papers, veneers, metal foils, etc.

109022/1938

layers and glued by pressing.

When stretched material is heated to the softening point, it generally shrinks, when it does not is under tension and the orientation of the molecules is reduced. The heating must therefore be avoided this shrinkage can be made under tension. Uniaxially stretched material can be heated when it is tensioned lengthwise. Biaxially stretched material is heated while it moves on successive curved surfaces of rollers. So becomes by having the material exposed to abrasion of the curved surface lengthwise as well as laterally, the surface shrinkage is avoided. The heating can be done evenly wider and faster if you look at the individual films heated after layering.

One method of layering is to just layer many layers of film of the same width. Another method is to fold one in order to obtain a layered material of a smaller width wide zigzag layer of film after being heated for stretching.

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Another feature of the method according to the invention for Production of a tough material by layering of many stretched film layers by compression molding at the softening temperature is that the individual Layers of the laminate do not have to be the same either in terms of the type of polymer or the degree of stretching of the film * Rather, it is possible to have many stretched layers, e.g. B. a high density polyethylene film on top of each other and on the top and bottom of this

2 laminate at a pressure of 200 kg / cm and at the

Softening temperature (128 - I3O ⁰ G) of the high density polyethylene film to glue one layer of a stretched polypropylene film on each one. This results in an article in which the individual layers are uniformly glued to one another and which has the properties of polypropylene on both surfaces. Even if the same polymer is used, the softening temperature increases as the degree of stretching increases. If an unstretched or slightly stretched polymer film is applied to the outside of a laminate made of many highly stretched polymer films of the same polymer and a paper layer is also applied to the unstretched film and the whole is pressed at the softening temperature of the highly stretched film, the unstretched film layer is almost melted and penetrates the paper and acts as an adhesive. There is no reduction in the orientation of the molecules in the general

1D9822 Π 936 " ⁸ "

stretched film instead. It is also possible to use a solution or paper or a stretched film in advance to coat an emulsion of a polymer or to stick an unstretched film on it, the resulting film Paper or the stretched film coated in this way on a stretched film of the same material or .Apply a layer body formed from it and the whole thing by pre-pressing at the softening temperature of the stretched film to stick. It is still possible if you have paper or a stretched film with you Coated low density polyethylene and the resulting paper or coated stretched film applied to a stretched high density polyethylene film, by subsequent pressing while heating to the softening temperature of the latter film Laminate with good mutual adhesion.

Finally, it is also possible, if one uses paper, that with an emulsion of polyvinyl chloride, polyvinyl acetate or polyvinylidene chloride was coated and then dried and coated layers of stretched polyvinyl chloride films at a pressure of

150 kg / cm and a temperature of 100 - 120 ° G glued together, a uniformly glued tough Laminate gets the on its surfaces the

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Has properties of paper.

A similar laminate can even be made using one instead of paper Veneer used.

For the production of substitutes for steel straps, belts or strings with a tensile strength in If the longitudinal direction is desired, uniaxially stretched film layers can be stuck together and bonded by pressure. If it is undesirable that the resulting laminate can break in the lateral direction, then it is useful as part of the laminate some Layers of a laterally or biaxially stretched film to use. It is also recommended to use longitudinally stretched films with fabrics, papers or with laterally stretched films Films which have been impregnated and coated with the same or a different polymer which has adhesiveness to the stretched film were to be layered together and by pressure too stick together.

Generally speaking, a biaxially stretched film is which has almost the same strength in both the longitudinal direction and the lateral directions, more suitable for the production of a shielded film,

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- 10 which is used for articles with paper surfaces.

The layered film made from a film stretched at a reduced uniaxial stretching ratio Material can be used to make tapes if it is feared that it will tear in a lateral direction and belts can be used, but then the resulting product becomes brittle and coarse. It is therefore not advisable to to do so. It is better to have the layers uniaxially stretched with the highest possible stretching ratio To layer the film at right angles or to layer the layers so that layers of the film have a high draw ratio biaxially stretched film with layers where the stretching is uniaxial with a high stretching ratio had been made to be mixed. This process improves flexibility, high toughness, resistance to low temperatures, impact resistance and other physical properties of the product can be improved »Compared with the traditional method of making ribbons and belts, in which the stretched articles of the desired thickness are manufactured in one operation, without a layering of thin stretched films takes place, it enables the described method according to the invention, Laying layers of films stretched sufficiently both lengthways and laterally on top of one another

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^: ■■■■ '■ - ii -

and to produce, through the improved orientation of the molecules, a product which is superior in ductility, high toughness, resistance to low temperatures and impact strength to that which is produced to avoid lateral brittleness at a reduced stretching ratio. This means that by the inventive method, in which a thin film is stretched so, M that it has a particularly high tensile strength, and then laminated together in layers and is bonded by pressing, products are obtained which are superior to the products in all physical properties produced by processes in which the rolling to produce the products of the desired thickness is carried out in one go without piling.

The present invention consists of two parts: one part relates to the production of layered material by making only layers from a stretched material Polymer film pressed, the other part relates to the removal of layered material in such a way that that stretched films and fibrous materials, paper, Veneers or metal foils pressed together. In the latter case, however, it is necessary that during the layering and pressure bonding of two or more stretched polymer layers the fibers, papers, Pourers or metal foils, the adhesive surfaces of which after them

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impregnated with the same or a different polymer which has an adhesive chain to the stretched film or coated and dried, or the stretched film, the surface thereof after coating dried with the same or a different polymer must be prepared in advance. Both of them will Layers layered together and heated to a temperature below the softening point of the stretched film and is above the softening point of the unstretched film that forms the coating, glued together by pressing.

If a particularly low elongation in the longitudinal direction is required, glass fibers are used as the fiber material. For example, a fiberglass article impregnated with a polyvinyl chloride or polyvinyl acetate emulsion is used as the core, around which a suitable number of layers of uniaxially stretched PVC film are layered, or glass fibers are sandwiched between two sets of layered layers. consisting of stretched films, one surface of which has been dried after being soaked with the emulsion mentioned, and heats the whole thing under tensile stress to 100 - 120 ° G and causes the uniform adhesion through continuous rolling at a pressure of 200 - * K) 0 kg / cm.

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By setting a suitable cross-section, depending on the size of the tape, you can at the same time create a thread-like shape or string-like material made of non-plasticized PVC obtained that has low elongation and good resistance against low temperature, against abrasion and Has impact.

The laminate, consisting of biaxially stretched PVG-PiIm is placed between veneer panels after application a PVC or acetate emulsion had been dried on a surface, and the whole thing is under

Heating to 100 - 12C ° C at a pressure of 100 - 200

2 -

kg / cm glued. This results in a tough veneer material » which is resistant to high and low temperatures, shock and moisture.

By uniaxially stretching a 60-100 jx thick, high-density polyethylene film in boiling water to 8-10 times its length, a stretched film with a thickness of 20-30 jx and a tensile strength of 60 kg / cm ^{2 can be} produced. After the film formed in this way has been heated by continuously conveying it under pressure on heated rollers in a room of 120-130 ° C., 10-20 layers of it are stacked on top of one another and by means of

"2

Rollers glued at a pressure of 100 - 500 kg / cm, where-.

109822/1336

uniformly connected to one another by the individual layers with hardly any deterioration in strength. You get a tough belt. At a With a narrower width, the product can be used as a belt or as a replacement for a steel belt, while with a larger width can be used as a conveyor belt instead of a steel or rubber belt. The ends such a belt can be tied together in the usual way, but there is best practice is to sand the ends with a grinding wheel thin and at an angle in such a way that that they do not overlap too much and then place them in a heating and gluing machine at 125-130 G, i.e. H. stuck at the softening point of the stretched film used for the belt. This allows the ends to look like this strongly connected to each other so that they do not tear apart under pressure.

The same applies to films made of polyvinyl chloride, polypropylene, Polystyrene, polymethyl methacrylate, polyacrylonitrile, polycarbonate, polyester, nylon, polyvinyl alcohol or Cellulose acetate. If one is uniaxially stretched, the thin films of these polymers have a tensile strength of 30 -? 0 g / mm. In the case of biaxial stretching the tensile strength changes according to the

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ratio longitudinal stretching: lateral stretching, will but greater as this ratio increases.

The following tables show the superior properties of thin films:

Table 1

Dependence of the tensile strength on the film thickness

Tensile strength of Polyfexg side pull thickness (mm) longitudinal tensile strength (kg / cm) strength

(kg / cm ^)

0.381 0.52 - 0.56 0.59 - 0.66

0.254 0.56-0.63 0.63-0.73

0.127 0.63-0.70 0.70-0.91

0.025 0.66-0.70 0.87-1.22

(James Bailey: Indian Rubber World; May 1948, S-. 227)

When using polypropylene films at a 5-fold stretching ratio at a temperature of 130 ^° C. (glycerine bath), the following values were obtained:

Table 2
Dependence of the tensile strength on the final film thickness

Thickness (mm) Tensile Strength (kg / cm)

0.100 31

0.200 25

0.300 24

0.400 22

^109822/1936 - ¹⁶ _B ; _{D 0RieiNAL}

In the present multi-layer materials, the tensile strength per unit cross section is almost unchanged maintain.

It is possible to produce a belt of excellent quality without further treatment, by using uniaxially stretched layers of nylon film with a high tear resistance are bonded to one another by pressure. It is worth noting that this belt has a much greater toughness than a belt that is under Using nylon fabric as the basis is made.

If pressure is exerted on the layered material in the course of the pressure-bonding process by means of rollers, this film, consisting of the material of a certain thickness, is also rolled out in the lateral direction. In doing so, its width is increased. In most cases, the layers of uniaxially stretched film therefore become stronger and less brittle in the lateral direction as a result of the pressure bonding than they were before the bonding. For this reason, these products can be used to manufacture belts, substitute materials for steel belts and straps, even if they do not have layers of biaxially stretched films

- 17 -109822/1936 BADORiGiNAL

170A9OQ

contain. But if the product should have a particularly high have lateral tensile strength, then as part of the layers of layered material is the use of biaxially stretched films with a particularly high lateral stretch ratio.

If necessary, the surface of the laminate to be provided with a pattern, the A press pattern is engraved on the surface of the pressure roller Apply rollers to the surface of the laminate, if you then use a roller that has a press pattern »

Becomes a stretched film or one made from it Laminate sandwiched between sheets of paper and the When the whole thing is pressed to bond, the product obtained is, due to the fact that paper is present on the surface, not slippery and therefore easy to print on. Made from bundles of aligned molecules the existing fibrils of the stretched film are similar in the Elongation-load curve of the paper fibers, the stretched one Film and the paper therefore contribute to the one another

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10982 2719 36

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Improvement in tensile strength in »It can therefore be said that the above-described joining of the Of the film with the paper of the mixed weaving and interweaving von Pasern is similar. If a paper is coated only with resin according to a conventional method, the resulting Product, since the molecules of the synthetic resin were not subjected to post-stretching, not the advantages of a Stretching on. If the synthetic resin content is too high, then the product shows the disadvantages of brittleness and Brittleness. Since the molecules of the synthetic resin are neither stretched nor aligned, the paper fibers together no improvement in strength can be achieved. Paper and a stretched film are layered together and pressed for bonding, a flexible and tough product can be obtained in which the stretched film and the paper together can contribute to an improvement in tensile stress, since the proportion of the undrawn Resin, with which the paper would be coated in advance as an adhesive, is so small, or only in one way thin layer is present that the amount of the polymer of the stretched film is much larger in proportion. When stacking paper on a uniaxially stretched film, the paper fibers also prevent the product from being created then at the side tearing, if at the same time no two

- 19 1098 2 2/1936

axially stretched film is used. The tensile strength in the longitudinal direction of a sufficiently uniaxially stretched film becomes five to ten times the size of paper. Becomes a Laying up stretched film in an amount that is a fraction of the amount of paper used, so is the tensile strength in the longitudinal direction of the resulting Laminate the same as that of two sheets of paper. Due to the increased amount of paper, the side Tear strength of the uniaxially stretched film similar to made of paper so that one can get the paper in the event of a sufficient tensile strength of the stretched film as filler material. That means that you have to manufacture of cords or the like, which do not require any particular tensile strength, paper of an inferior quality and can use in a larger proportion, with it becomes possible to reduce the thickness and the amount of the stretched film. It is necessary when you have one want to insert stretched film between sheets of paper, both sides of the paper with a synthetic resin or a Adhesive to provide. If the paper only needs to appear on the surface, the synthetic resin will only apply to one Surface applied.

Will the paper or the stretched film with a thin Layer of the same polymer or a different polymer,

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170490Q

which has adhesiveness to the former, is effected by pressing in the case of the one according to the invention Stratification processes carried out with heating carried out heating to the softening temperature of the stretched film that this is not or only slightly stretched polymers are heated above the softening point up to the melting point and so acts as an adhesive and secures the paper to the stretched film or to the laminate under pressure glued on »

Until now it was necessary when gluing polyethylene to oxidize the surface of the polyethylene in an electric arc in order to increase its adhesiveness cause. According to the present invention, however, it is possible if one uses a film of polyethylene low density applied in a thin layer on paper or a stretched film, the resulting film or the paper thus obtained on a stretched film of high density polyethylene or on one made therewith Laminate is glued on by heating to 100 - 110 ° C at a pressure of 100 kg / cm. Here glued layers are obtained which adhere to one another as tightly as if they were welded to one another would be.

- 21 109822/193 6

BATH ORIGINAL

The same result can still be obtained if paper or a stretched film is mixed with an emulsion of high-density polyethylene or with an emulsion obtained in the emulsion polymerization of ethylene and approx. 15 % acrylamide (Poly EM, Gulf Oil Corp. USA) is obtained, thinly coated and the paper or the coated film thus obtained by heating to 125 ■ -. 13O ⁰ C at a pressure of 100 kg / cm stuck to a stretched polyethylene film with high density. If an aluminum foil is used in place of the above-mentioned paper, a tough metal foil backed with a biaxially stretched film can be obtained.

Coating can be done very easily if one takes a thin layer of coating on the surface Layer or a laminate made of stretched film or a paper with the same or a different polymer, which has an affinity for the former, adds a surface-active compound or an adhesive.

The method of the present invention can apply to any of them other thermoplastic resins.

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Thermoplastic resins that have the ability to make fibers, to form, are generally denser in structure, with the crystalline zones being improved the molecular orientation are increased and the softening point (correspondingly also the melting point) compared to the, non-oriented resin is increased. The extent of this increase differs depending on the type of synthetic resin. With crystalline polyethylene ^ (high density) makes the increase 10 - 15 ° G * In particular becomes the softening point of a resin which is subjected to heat treatment after stretching was increased more. When stretched polyvinyl chloride is subjected to heat treatment, the softening point becomes (in the present case the temperature at which it shrinks to a certain percentage) by approximately 20 - 25 ° G increased.

Jk In the method according to the invention, by which the stretched film is pressed for bonding, the difference between the softening temperature and the unstretched amorphous resin is increased by this temperature-increasing effect, which results from the temperature treatment taking place during the bonding. Therefore, if a resin coated with the paper, fabric or a stretched film is heated to its softening or melting point, which is below the temperature at which the molecules of the stretched film lose their orientation, so

109822/1936 ^! " ² _b ³ _a d OR.GINAU

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the unstretched resin acts as an adhesive for bonding the paper to the stretched film, and in this way a tough laminate material is obtained. In this case, the softened unstretched resin that acts as an adhesive, more fluid than the stretched FiIm ₀ üie.Druckverklebung can for this reason, as stated in claim 4, bottom

half 50 kg / cm.

The softening point of the stretched film is in a very large temperature range below the melting point, in the manufacture of laminates one works at lower temperatures with a higher pressure, while one works at a lower pressure the temperature increases »At higher temperatures, however, the oriented molecules tend to lose their To lose alignment when one d: .e pressure bonding not correspondingly short-term, d. H. at high Speed, performs. With high pressure you get a better bonded layer material “Es could be experimentally confirmed that when the production of the laminated materials at a pressure below 50 kg / cm and at such a temperature, in which the alignment of the molecules is not yet loosened, the assembled ones are made

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17049

Later in the course; tend to use to leaf apart. If, on the other hand, the layer material is placed at the same pressure, but one The temperature at which the layers obtained do not peel apart is determined by the heating loosened the alignment of the molecules and ultimately reduced the tensile strength »General Said it is important to have a laminate material excellent tensile strength to maintain the tempera door, in which one at the Bmckverkriebe Product whose layers do not easily peel apart, want to be preserved, to be selected in such a way that one at

2 the highest possible pressure above 100 kg / cm can work. The following examples serve to provide a better understanding of the invention. A restriction the invention is not intended to be made by them.

Example 1:

A 90 micron thick and 1 m wide polyethylene film high Density, which had been preformed by the blow molding process, was taken up with a pinch roller and in an upper and a lower part cut up «The two parts were in boiling water nine times Stretched length and as two stretched films, 30 Ai each thick and 33 cm wide, wound up. One of these films was made by one under tension continuous circulation on by means of steam on '

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1704300

130 ° G heated rollers, which were located in a heated to 125 ° C seam, a heat treatment subjected and in 20 layers, each 16 mm wide, Folded zigzag. With the film folded in this way, make a roller out of silicone rubber, the rectangular cavities 20 mm wide and 5 sun deep he was using a metal roller to make the cavities of 20 mm wide and 1 mm deep, in one

2 ■ ""
Pressure of 200 kg / cm rolled and glued together.

A substitute material for steel strips with a width of 20 mm and a thickness of 0.5 was now

■ Hold 2, which had a tensile strength of fW - 60 kg / cm.

Example 2:

A biaxially stretched film made of non-plasticized PvO, which had been stretched threefold in the longitudinal direction and in the lateral direction, was inserted between two sheets of sulphate pulp, which after the emulsion, consisting mainly of polyvinyl acetate, was sprayed onto one side of the Sheets taking place coating, were dried, or it was the named film, after it had been coated with the mentioned .Emulsion on both sides and dried _A inserted between two sheets of paper and then heated with steam. Rollers let revolve in a heated Haum, whereby the. Paper and the stretched film were preheated to 110 ° G *

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- 26 -.
Then the bonding took place with a pressure of

15Q kg / cm by a pressure roller set composed of a rubber roller and a metal roller, followed by cooling. A tough, layered paper was obtained which consisted of stretched film in the intermediate layer and paper on the lower and upper surface. This paper could not only. It was used for the production of heavy sacks, but was also suitable for the production of corrugated cardboard due to its high stiffness compared to its weight The surface of the layered paper thus obtained has different properties of the paper, so that it can advantageously be used in the same way as paper, with only small amounts of pulp and resin W being used . If you continue to manufacture the

The above-mentioned layer materials used a biaxially stretched polystyrene film together with the paper, then you get a product that is very tough and much better than the starting material for production of corrugated cardboard.

Example 3:

A 25 cm wide and 0.1 ram thick tape made of JUylon 6,

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4.5 times after the molding made by extrusion had been stretched, was by continuously rotating on heated rollers in a heated room to 170-190 ° C heated. Then 10 parts of it were stacked one on top of the other and rolled at one

2
Pressure of 500 kg / cm pressed. A tough nylon belt was obtained that was 30 cm wide and 0.85 mm thick.

Example k:

Copper wire was poly EM (an emulsion polymer of ethylene with acrylamide and a polymer concentration of ^ O - "50%) of Gulf Oil Corporation, and dried by pre-heating to 130 ⁰ G, the coated wire was heated at 128 ° G with a 0th , 1 mm thick tape obtained by pressure bonding three high-density polyethylene films stretched to eight times the length. The whole was pressed by continuous rolling with Teflon rollers with a semicircular groove. The product thus obtained was very good Extensible and tough. In terms of its properties, it was superior to copper wire wrapped with a non-oriented resin ° C. The wire obtained in this way, which was wrapped with a stretched film, was very flexible and, in comparison, lower

- 28 109822/1836

Temperature resistant. Compared to wires with the usual non-oriented resins are coated, the wire thus obtained is these for use as Cable for electrical household appliances superior »Because the stretched film when heated to a suitable temperature shrinks, it is possible to fix the film spool wound around an object by heating.

Example 5:

A polyvinyl chloride film 20 µm thick by stretching 3 times in the longitudinal direction and 2.5 times in the lateral direction, biaxially stretched polyvinyl chloride film was coated with vinyl acetate-acrylic emulsion on both sides. (BondCV 350), which was previously diluted with water in a ratio of 1: 3 and contained 0.2 % wetting agent (Lipon F, Lion Oil and Fat Co), coated and air-dried. The coated film was sandwiched between two sheets of Kraft paper. After a flat chrome-plated steel plate had been placed on it, the whole was bonded by pressing by means of a hot press at 80 ° C. and at a pressure of 50 kg / cm in the course of one minute. It was then cooled to 50 ° G. The sealing material removed after the pressure was turned off showed excellent tensile strength and resistance to peeling and could be used as a well-suited raw material for making heavy bags.

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Claims (3)

Claims 1, method of making laminates, thereby characterized in that at least one layer of a stretched film, the molecules of which are spatially oriented, with at least one layer from org. or anorg. Fibrous materials, from papers, sheets, veneers or metal foils under pressure by means of an adhesive at the softening temperature this adhesive is glued together uniformly, with no reduction in the orientation of the molecules of the stretched film takes place. 2. The method according to claim 1, characterized in that at least one layer of a thermoplastic polymer film, in which the spatial orientation of the molecules through Hedges of the preformed film had been improved with at least one layer of org. or anorg. Fibrous materials, from papers, sheets, veneers or metal foils under Liruck by means of the same, but not aligned and a softening point lower than that ν - stretched film having polymers acting as adhesives, is uniformly glued, that here the temperature is chosen so that no significant reduction the orientation of the molecules occurs and that this temperature lies in a range between the softening point and the achraelz point of this adhesive. - 30 109822/1936 3. The method according to claim 1, characterized in that at least one layer of a thermoplastic .folymerfilmes, in which the orientation of the molecules had been improved by pecking the preformed film, with at least a location from org. or anorg. Fibers, from papers, sheets, veneers or metal foils Pressure by means of another polymer acting as an adhesive, which is viable to the stretched material mentioned having, are uniformly glued to one another that the temperature is chosen so that no significant reduction the orientation of the molecules of the stretched film occurs and that this temperature is in a range between the softening point and the melting point of this adhesive. ^. Method according to claim 1, characterized in that at least two layers of a thermoplastic polymer film, in which the orientation of the molecules by stretching the || preformed film had been improved, Dei a softening temperature of the film mentioned, in which there is still no significant reduction in the orientation of the molecules takes place, are uniformly glued together at a pressure of at least 50 kg / cm. 109822/1936