DE60314992T2 - METHOD AND DEVICE FOR PRODUCING A MULTILAYER STRIP OF FLEXIBLE MATERIAL, SUCH AS, FOR EXAMPLE, PAPER AND NONWOVEN FABRIC, AND MULTILAYER MATERIAL AND PRODUCT PRODUCED BY THE METHOD - Google Patents

Abstract

Method for producing a multi-ply web (14) of flexible material, such as paper and nonwoven material and a multi-ply product produced according to the method. A first pattern roll (5), having a three dimensional pattern of alternating raised (6) and recessed portions (7) transfers glue to a first (1) web shaped flexible material in a first press nip (8) in glue sites (17) covering an area corresponding to between 0.03 and 9 % of the total area of the first web material and sparsely distributed over substantially the entire area of the first (1) web material. A second (10) web shaped flexible material is brought in contact with the glue applied side of said first (1) web material in a second press nip (12) between a second pattern (13) having a three-dimensional pattern corresponding to that of the first pattern roll, and an impression roll (9). The first and second pattern rolls (5, 13) are driven in registry.

Description

Technical area

The The present invention relates to a method for producing a multilayer web of flexible material such as paper and nonwoven fabric by gluing the layers. In particular, it concerns the manufacture of tissue products, such as toilet and kitchen paper, Paper towels, Towels, Napkins, handkerchiefs, wipes and the like. The invention further relates to a multilayer web of flexible Material such as paper and nonwoven comprising at least a first and a second layer, which by means of gluing in one Adhesive patterns are interconnected. The invention also relates a product formed from the multilayer web.

Background of the invention

It is very common two or to connect multiple tissue layers to the finished tissue product form. This will result in a more flexible and softer tissue product compared with when only a single situation with one appropriate strength and a corresponding basis weight instead of the connected product. The absorption capacity and paper thickness (bulk) are above improved.

The Joining two or more tissue layers is often done by adhesive. Also, a mechanical embossing of the layers is often performed before they are glued together. It is also known two layers only over a mechanical imprint to connect, with a mechanical connection of the layers to the embossed points occurs.

By z. B. the EP-A-796,727 It is known to emboss two paper plies first with a three-dimensional structure having alternating raised and recessed portions, after which adhesive is applied to one of the plies and the two plies are joined in a press nip between the two embossing rolls so that the raised portions of the corresponding one Layers are glued together. A similar embossing process is in the EP-A-738 588 discloses according to the adhesive also has a coloring effect.

In the WO 95/08671 is z. As a so-called. Nested embossing disclosed in which the two individual embossed layers are combined and connected in such a way that the raised portions of a layer engage in the recessed portions of the opposite layer.

By the US-A-5,443,889 For example, there is known a method of bonding two layers of paper, each conveyed over a pattern roll, the pattern rolls having alternating raised and recessed portions and adhesive applied to a sheet as it passes over the roll. The two paper layers are then bonded in a nip between the two pattern rolls which register with each other so that bonding and compression of the paper layers are made in a pattern corresponding to the raised portions of the pattern rolls.

One Disadvantage of occurring in connection with the embossing of a paper web, being punctiform is that a significant reduction in strength at the embossing and splices occurs, the strength properties of affect the entire paper product. Strength reductions of up to 70% of embossed paper compared with a corresponding unembossed paper are not uncommon.

The US-A-3,672,950 discloses a method of making a quilted or cushioned adhesive-bonded tissue product, wherein the adhesive is applied in a certain pattern to a tissue layer in a nip between a first pattern roll and a backing roll. This layer is bonded to another layer in a press nip between the same backing roll and a second pattern roll provided with a pattern corresponding to that of the first pattern roll and driven in registry with the first pattern roll. The two layers are in different states of tension during the bonding process, resulting in a quilted or cushioned product.

Task and most important features the invention

The The object of the present invention is a method for Producing a multilayer web of flexible material, such as To provide paper and nonwoven fabric and combinations thereof wherein the at least two layers of flexible material with each other are connected. The bonding should be gentle to the material, so that maintain the material structure of the layers substantially the same becomes like its strength properties. The absorption capacity and paper thickness of the finished product should, however, be high.

This has been accomplished in accordance with the invention by bringing a first pattern roll having a three-dimensional pattern of alternating raised and recessed portions into contact with an adhesive applicator in a first nip adhesive in a pattern corresponding to the configuration of the tops of the raised edges sections on a first sheet-like flexible material, wherein the configuration of the pattern of the first pattern roll is selected so that adhesive at adhesive sites covering in a range corresponding to between 0.03 and 9% of the total area of the first sheet-like flexible material and sparsely over in Substantially the entire surface of the first sheet-like flexible material is spread onto which first sheet-like flexible material is applied, wherein a second sheet-like flexible material in a second press nip between a second pattern roll having a three-dimensional pattern of alternately raised and recessed portions corresponding to the pattern of the first Pattern roll and a counter roll is brought into contact with the side of the first sheet-like flexible material on which the adhesive has been applied, wherein the web tension of the first and second sheet-like flexible material are substantially equal, when they are inserted into the second press nip, the first and second pattern rollers register with each other so that the first and second web-shaped flexible materials are compressed in a pattern corresponding to the configuration of the tops of the raised portions of the first pattern roller and bonded together.

By these methods will not be a real one in connection with the lamination embossing the web occur, but only a gluing of the layers in an adhesive pattern. A reduction in the strength of the finished product This avoids and at the same time a volume between the layers generated between the splices, so that the paper thickness and the absorbency elevated is. The paper thickness of the individual layers also remains after the Maintaining lamination process substantially.

According to one embodiment the adhesive is colored adhesive.

at an embodiment The invention provides at least one of the two layers prior to lamination with the opposite Layered with a three-dimensional pattern.

According to one another embodiment at least two layers before lamination with a three-dimensional Pattern provided, wherein the patterns of the at least two layers different Have structures, of which z. B. a pattern relatively fine and another pattern is relatively coarse.

According to one yet another embodiment is at least one layer of adhesive strips or curing binder z. B. reinforced latex. The said curing agent is cured after lamination.

The size of each glue site should be between 0.15 and 150, preferably between 0.5 and 100 mm ^2, and more preferably between 1 and 15 mm ² . In an alternative embodiment, the size of each glue site is between 150 and 400 mm ² . The number of glue sites per area unit should range between 25 and 350.000, preferably between 300 and 180,000, more preferably from 800 to 50000 glue sites per m ^2. It is emphasized that the glue sites may be evenly distributed over the area of the sheet material, but they may also be distributed unevenly, e.g. B. be arranged in spaced groups.

Of the Term punctiform refers in this regard any form of glue sites, such as small ones Points, lines, figures, letters, fantasy patterns or any desired Shape.

The Invention further relates to a multilayer web of flexible material, such as paper and nonwoven fabric comprising at least one first and a second layer, which by gluing at the adhesive sites, which form an adhesive pattern, are interconnected, wherein the Adhesive sites a range corresponding to between 0.03 and 9% the total area cover the situation and over essentially the entire area the location sparse are distributed and being an outer surface of the multi-layered train exactly opposite the glue sites essentially no and the opposite Outer surface of the multilayer track slightly condensing imprints in the material, in connection with the bonding of the layers arise.

Further Features of the invention are described in the following description and the Claims disclosed.

Description of the drawings

The Invention will be described below with reference to an embodiment, which is illustrated in the accompanying drawings.

1 shows a schematic side view of an apparatus for carrying out the method according to the invention.

2 Figure 3 is a schematic cross-section of one embodiment of a two-ply paper made according to the method.

3a -c are plan views of some adhesive patterns on a paper sheet according to the invention.

4 Figure 3 is a schematic cross-section of one embodiment of a three-ply paper according to the invention.

Description of an embodiment

1 shows an apparatus for producing a two-ply material z. As paper, especially tissue paper. A first paper web 1 is about a roller 2 conveyed in the direction of an adhesive application device. This includes an adhesive chamber 3 from the adhesive to an adhesive transfer roller 4 is applied. The adhesive transfer roller 4 is in contact with a first pattern roll 5 They alternate over their circumference with a pattern of alternating sublime 6 and recessed sections 7 is provided. The adhesive transfer roller 4 only contacts the tops of the raised sections 6 so that glue is only applied to this. The paper web 1 enters a press nip 8th between the first pattern roller 5 and a centrally located counter roll 9 , Adhesive thus becomes in a pattern corresponding to the configuration of the tops of the raised portions 6 on the first paper web 1 applied. The pressure in the press nip between the pattern roll 5 and the counter roll 9 is only high enough to transfer the adhesive to the paper web 1 to accomplish. However, it should preferably no deformation of the paper web occur, ie no imprints of the raised portions 6 the pattern roller 5 in the paper web.

A second paper web 10 becomes a roller 11 in a press nip 12 between a second pattern roll 13 and the centrally arranged counter-roller 9 promoted. The second pattern roller 13 has a three-dimensional pattern of raised 14 and recessed sections 15 according to the pattern of the pattern roller 5 on. The term "corresponding" means in this regard that the raised sections 14 either the same shape and size of the effective area as the raised portions 6 the first pattern roller 5 , the same shape but a larger effective area than the raised sections 6 the first pattern roller 5 so that they extend beyond the outer perimeter of the glue spots passing through the first pattern roller 5 may extend or have a different shape and a larger effective area than the raised portions 6 the pattern roller 5 exhibit. For example, an adhesive pattern passing through the first pattern roll 5 is provided, in the form of groups of three points, in a triangular pattern, as in 3a is shown, are arranged, wherein the raised portions 14 the second pattern roller 13 either exactly the same or slightly larger than the adhesive pattern or z. B. in the form of a triangle 20 that covers the three points. In all these cases, the relative position of the patterns on the two pattern rolls corresponds 5 and 18 each other.

The web tension of the first and second layer 1 and 10 are essentially the same when placed in the second press nip 12 be introduced. There will be no shortening effect due to the lamination. The two pattern rolls 5 and 13 are driven in register to each other, so that the first and second paper web 1 and 10 in a pattern corresponding to the configuration of the adhesive pattern passing through the first pattern roller 5 is provided, compressed and glued together.

It is preferred that a central counter roll 9 for both the first and second pattern rolls 5 and 13 is used as it is in 1 is shown. However, it would of course also be possible two separate counter rolls for the first and second pattern roll 5 and 13 to use and to synchronize them so that they run in the register.

Also in this second press nip, the pressure should be low and only high enough to stick the paper webs together 1 and 10 to accomplish. The pressure in the second press nip should only be so high that only slightly compressive impressions 19 exactly opposite the adhesive sites in the second layer 10 , that of the second mating roll 13 is facing.

The opposite outer surface of the multilayer web, ie the area of the central counter-roller 9 Without being influenced by the lamination process without compressive impressions in the material, its structure is substantially retained with respect to the adhesive sites. The laminated multi-layer product is with 16 designated.

The pattern on the two pattern rolls 5 and 13 may be optional, but should be chosen so that adhesive in an amount corresponding to between 0.03 and 9%, preferably between 0.1 and 6% of the total surface area of the paper web 1 is applied to the paper web. In the present case, the glue sites are sparsely distributed over substantially the entire area of the laminated product. With the method according to the invention it is possible to achieve a very accurate positioning of the glue spots, whereby a very small amount of glue is required. This means advantages in terms of softness, drapability, absorption etc. In the case where the adhesive pattern comprises several individual adhesive sites, the number of adhesive sites per unit area should be between 25 and 350,000 adhesive sites per m ² , preferably between 300 and 180,000 adhesive sites per m ^2, and more preferably between 800 and 50,000 adhesive sites per m ² . In one embodiment, the size of each glue site is between 0.15 and 150 mm ² , preferably between 0.5 and 100 mm ^2, and more preferably between 1 and 15 mm ² . According to an alternative embodiment, the size of each glue site is between 150 and 400 mm ² , due to certain composite adhesive patterns comprising thin lines, e.g. B. with a width of 1 mm, applies, the z. B. form a symbol or figurative pattern. In such an embodiment, the number of adhesive sites per m ^{2 will be} in the lower range of the above interval, e.g. B. at less than 800.

in the Trap of big ones Adhesive sites can be screened Patterns are used, which means that each glueing unit composed of several small grid points. The size of the glue spots in this case is considered the circumscribed area of the combination the grid points which form an adhesive pattern unit defined.

According to one another embodiment is the adhesive pattern of continuous lines, the z. B. a Form network, built.

preferred Adhesives are commonly used for paper such as carobxymethyl cellulose (CMC), polyvinyl alcohol (PVOH), ethylene vinyl acetate (EVA), polyvinyl acetate (PVAc), ethylene acrylic acid, vinyl acetate acrylic acid, styrene acrylic acid, polyurethane, Plyvinylidene chloride, starch, chemically modified starch, Dextrin, water-soluble Polymers such as latexes and milky colloids in which naturally or artificial rubber or plastics dissolved in water are. In the case of the material webs of a different material As paper, of course, adhesives are chosen that for this Materials are suitable.

It It is preferred that adhesives having a relatively high dry content can be used, as this allows an accurate positioning of the adhesive sites.

colored Adhesives can also be used that have a visual effect and therefore effect a pattern giving the material an effect.

In 2 An example of a two-ply paper made in accordance with the invention is shown in which the glue sites between the two paper plies 1 and 10 With 17 are designated. Between the glue spots 17 are the paper layers 1 and 10 free and not attached to each other and open spaces 18 are produced that increase the paper thickness and absorbency of the material, which are properties that are e.g. B. are important for soft paper. Essentially the total paper thickness of the individual layers is retained after lamination. The second paper web 10 may be slightly compressive indentations exactly opposite the glue spots 19 caused by the pattern roller 13 exhibit.

The 3a -c show some examples of adhesive patterns, with individual spots of adhesive 17 arranged in the form of dots or lines to form different patterns. The glue spots 17 can also be in the form of continuous lines, the z. B. form a network pattern exist.

The paper webs 1 and 10 which are joined can either be smooth or have a three-dimensional structure previously provided in the process, e.g. B. during the formation, dewatering and / or drying of the paper web. A three-dimensional structure may also be provided by embossing the paper webs prior to lamination. The method according to the invention is very gentle to such patterns, so that it remains essentially intact throughout the joining process.

4 shows an embodiment of a three-ply paper in which the layers 1 . 10 and 20 provided with a three-dimensional pattern before lamination, z. B. embossed were. The structures of the embossed patterns are different, so that the pattern structure of the middle layer 10 coarser than that of the two outer layers 1 and 20 , A very thick or voluminous product is achieved. The glue spots 17 between the layers 1 and 10 can, as disclosed, be with respect to the glue sites between the layers 10 and 20 be arranged offset or exactly opposite each other. Other combinations of different embossing patterns than those in 4 can of course be used. Multilayer products with different structures on opposite sides can be produced if the two outer layers have different embossing structures, for example a coarser side and a smoother side. So-called micro-stitched embossing patterns can also be used. One or more layers may also be unembossed. In the case of a two-ply product, a two-sided product is achieved when one ply is embossed and the other remains unembossed or has a different embossed structure.

The embossing patterns used for the different layers can also be the same. In this case, the layers may be coined together and then laminated by Ver to be separated according to the invention. They can also be embossed separately before lamination.

One important advantage of the invention is that the paper in the Essentially its strength properties throughout the bonding process maintains. For many other connection operations where an embossing and Deformation of the paper webs in connection with the lamination occurs, the strength properties are reduced. In the event that the laminated multilayer web has a substantially smooth structure it can be transformed into dense rolls or dense folded products become what space and cost savings means.

The laminated multi-ply product may also be embossed, if desired, due to the strong ply bonding provided by the adhesive sites after the bonding operation, thereby producing a softer material. The effective ply adhesion is due to the pronounced adhesive effect of the second pattern roll 13 is provided in the register with the adhesive transfer roller 4 running, scored. This ply-bonding effect is used when converting, for. B. rolls of the paper product is not reduced, which may be the case with a ply adhesion by embossing.

Three or several layers of paper can of course with be connected to the method described above. Thus, two or multiple layers enter the first and / or second press nip.

different Paper types with different properties in terms of absorbency, Grammage, Manufacturing technology, fiber composition and chemical additives can be found in the different layers are used.

The Method is also for use with paper sheets having holes therein suitable because the main part of the holes over the entire connection process will remain intact and not with adhesive filled what will normally be the case when the layers are together be glued.

At least a paper layer can also with thin strips of glue or curing Binders such as latex to be reinforced. The reinforcement can z. B. on the outside of the bonded product after lamination and in the register for Connection process done. In the case of a curing binder is the Paper product after lamination z. B. by a heat treatment hardened. If the paper layers are reinforced in this way, can be very thin materials used whose use is otherwise due to insufficient strength to Handling in a conversion process or donor not possible would have been.

The multi-layered web can become a desired product, such as Rolls, folded towels, towels, Handkerchiefs, Napkins etc are converted. It would be beneficial the multilayer Railway according to the invention to be used in so-called coreless rolls starting from the middle which the paper is taken from the middle of the roll. At a usual multilayer web, in which the bonding of the layers with the embossing in conjunction stands, the innermost revolutions, which are compressed rather strongly, so that the embossing is more or less destroyed, do not come out as a satisfying product. In the multilayered Railway according to the invention on the other hand, lamination of the sheets is of any patterning Effect by embossing or similar is separated and thus also the innermost rounds make the coreless roll a suitable product.

Claims (25)

Method for producing a multilayer web ( 14 ) of flexible material such as paper and nonwoven fabric by gluing the layers, characterized by bringing a first pattern roll ( 5 ) with a three-dimensional pattern of alternately raised ( 6 ) and recessed sections ( 7 ) with an adhesive application device ( 4 ), which in a first press nip ( 8th ) Adhesive in a pattern corresponding to the configuration of the tops of the raised portions ( 6 ) to a first sheet-like flexible material ( 1 ), wherein the configuration of the pattern of the first pattern roll ( 8th ) is selected such that adhesive at adhesive sites ( 17 ) covering an area corresponding to between 0.03 and 9 percent of the total area of the first sheet-like flexible material ( 1 ) and sparsely distributed over substantially the entire area of the first sheet-like flexible material, onto the first layer (FIG. 1 ), wherein a second sheet-like flexible material ( 10 ) in a second press nip ( 12 ) between a second pattern roll ( 13 ) with a three-dimensional pattern of alternately raised ( 14 ) and recessed sections ( 15 ) according to the pattern of the first pattern roll ( 5 ) and a counter-roller ( 9 ) in contact with the side of the first sheet-like flexible material ( 1 ) on which the adhesive has been applied, wherein the web tension of the first and second layer ( 1 . 10 ) is substantially the same when in the second press nip ( 12 ), the first and second pattern rolls ( 5 . 13 ) register with each other so that the first and second sheet-like flexible materials ( 1 ) in a pattern corresponding to the configuration of the tops of the raised portions ( 6 ) of the first pattern roll ( 5 ) are brought together and glued together. A method according to claim 1, characterized in that adhesive at adhesive sites ( 17 ) on the first layer ( 1 ) comprising an area corresponding to between 0.1 and 6 percent of the total area of the first sheet-like flexible material ( 1 ) cover. Method according to claim 1 or 2, characterized in that the pattern formed by the raised portions ( 14 ) of the second pattern roll ( 13 ) has a larger area than that through the raised portions ( 6 ) of the first pattern roll ( 5 ), so that the pattern of the second pattern roll ( 13 ) via the adhesive sites ( 17 ) passing through the first pattern roll ( 5 ) extends beyond. Method according to one of the preceding claims, characterized characterized in that the adhesive is colored adhesive. Method according to claim 1, characterized in that at least one of the layers ( 1 . 10 ) is provided with a three-dimensional pattern, which is provided on the layer while it is wet, during drying of the wet layer and / or in a dry state before the lamination with the opposite layer. Method according to claim 5, characterized in that at least two layers ( 1 . 10 ) are provided with a three-dimensional pattern before the lamination, wherein the patterns are provided on the at least two layers having different structures, wherein, for example, one pattern is relatively fine and the other is relatively coarse. Method according to one of the preceding claims by amplifying at least one of the layers with adhesive strips or curing Binders e.g. Latex. A method according to claim 7, characterized by curing the Binders after lamination. Method according to one of the preceding claims, characterized in that the size of each adhesive site ( 17 ) is between 0.15 and 150 mm ² , preferably between 0.5 and 100 mm ^2, and more preferably between 1 and 15 mm ² . Method according to one of claims 1 to 8, characterized in that the size of each adhesive site ( 17 ) is between 150 and 400 mm ² . Method according to one of the preceding claims, characterized in that the number of adhesive sites ( 17 ) per unit area between 25 and 350,000 adhesive sites per m ² , preferably between 300 and 180,000 adhesive sites per m ^2, and more preferably between 800 and 50,000 adhesive sites per m ² . Multilayered web ( 16 ) of flexible material, such as paper and nonwoven, comprising at least a first ( 1 ) and a second layer ( 10 ), which are adhered to adhesive sites ( 17 ), which form an adhesive pattern, are interconnected, characterized in that the adhesive sites ( 17 ) cover an area corresponding to between 0.03 and 9% of the total area of the ply and are sparsely distributed over substantially the entire area of the ply, and that an outer surface of the multi-ply web is located exactly opposite the glue sites ( 17 ) substantially none and the opposite outer surface of the multilayer web slightly compacting imprints ( 19 ) in the material used in connection with the bonding of the layers ( 1 . 10 ) arise. Multilayer web according to claim 12, characterized in that the adhesive sites ( 17 ) a total area between 0.1 and 6% of the total area of the corresponding location ( 1 . 10 ). Multilayer web according to one of Claims 12 or 13, characterized in that the size of each glue point ( 17 ) between 0.15 and 150 mm ² , preferably between 0.5 and 100 mm ² , and more preferably between 1 and 15 mm ² . Multi-ply web according to claim 12 or 13, characterized in that the size of each adhesive site ( 17 ) is between 150 and 400 mm ² . Multilayer web according to one of Claims 12 to 15, characterized in that the adhesive is applied to the adhesive sites ( 17 ) is colored. Multilayer web according to one of Claims 12 to 16, characterized in that at least one of the layers ( 1 . 10 ) has a three-dimensional pattern that was provided prior to bonding to the opposite layer. Multilayer web according to claim 17, characterized in that at least two layers ( 1 . 10 ) have a three-dimensional pattern provided prior to bonding to the opposing layer, the patterns having different structures on the at least two layers, eg, one pattern being relatively fine and the other pattern being relatively coarse. Multilayer web according to claim 17 or 18, characterized in that the multilayer web has an outer side of relatively coarse three-dimensional structure and an outer side of relatively smooth structure. Multilayer web according to one of Claims 17 to 19, characterized in that the multilayer web at least three layers with a central layer, which is a relatively coarse three-dimensional Structure having. Multilayer web according to one of Claims 12 to 20, characterized in that at least one layer with adhesive strips or curing Binders e.g. Latex reinforced is. Multilayer web according to one of Claims 12 to 21, characterized in that at least one of the layers ( 1 . 10 ) Has holes. Roll, folded towel, rag, handkerchief, Diaper and the like from sheet material, characterized in that the sheet material is a multilayer Railway according to one of the claims 12 to 22 is. Roll of sheet-shaped Material according to claim 23, characterized in that the roller a coreless roll, which is unrolled from the middle. Product of sheet material according to claim 23 or 24, characterized in that the web-shaped material Tissue paper is.