RU2426649C1 - 3d embossing - Google Patents

Abstract

FIELD: process engineering.

SUBSTANCE: embossing shaft has structured embossing surface to interact with thrust shaft. Note that said structured embossing surface comprises external kedges of external recesses starting from shaft base peripheral surface. Note also that base areas of said external ledges or recesses differ. Heights of depths of said ledges or recesses in radial direction of said shaft starting from base peripheral surface also differ. Angles between sections of lateral walls and adjacent base peripheral surface of said ledges or recesses also differ. Besides, at least one ledge or recess includes lateral walls with at least two different angle of inclination between lateral wall sections and adjacent base surface. Selected aforesaid angles exceed 30°.

EFFECT: visually different embossed surfaces.

28 cl, 15 dwg

Description

Technical field

The invention relates to an embossing shaft for the manufacture of fibrous products, especially products from thin paper (tissue paper), non-woven materials or hybrids from them, and preferably hygienic and cleaning products with the predefined distinguishing features specified in paragraph 1 of the claims. The invention also relates to a device for manufacturing such fibrous products, to a method for manufacturing multilayer fibrous products, and to a fibrous product.

Background to the invention and a description of analogues and prototype

Hygienic or wiping products generally include all types of tissue paper: paper creped in a dry state; wet creped paper; paper dried by hot air suction (SPGV); cellulose or pulp packs; or all types of nonwoven materials, or combinations thereof; laminates or mixtures thereof. Typical properties of these hygienic and wipe products include: reliable absorption of tensile stress energy, drapability, good textile-like flexibility, properties that are often referred to as “bulk softness”, higher surface softness, and large specific volume with tangible thickness. Desirable are: the highest possible ability to absorb liquid and, depending on the application, suitable strength in wet and dry conditions, as well as a visually attractive appearance of the outer surface of the product. These properties, among other things, allow the use of these hygienic and cleaning products, for example, as cleaning cloths, for example: paper towels or nonwoven cloths, windshield cleaning cloths, technical cleaning cloths, kitchen paper, etc .; as hygiene products, for example: toilet paper, paper handkerchiefs or handkerchiefs made of nonwoven fabric, household towels, towels, etc .; as cosmetic wipes, for example: face wipes, sanitary napkins or diapers (it should be noted that only some products of this purpose are mentioned here). In addition, hygiene and cleaning products can be dry, wet, wet, printed or pre-processed in any way. In addition, hygiene and cleaning products can be folded, layered or laid separately, stacked or rolled up, connected or not connected in any suitable way.

According to the above description, the products can be used as products for personal hygiene and for household purposes, as well as for commercial and technical use. They are adapted to absorb liquids, remove dust, for decorative purposes, for packaging or even for use as a supporting material, as is usually the case, for example, in medical practice or in hospitals.

If thin paper is to be made from pulp, then the process essentially includes: forming, using a headbox and forming a mesh part; drying part (either drying by suction of hot air, or conventional drying on a Yankee cylinder). The manufacturing process also typically includes a creping process essential for the manufacture of tissue paper, and finally, typically includes monitoring and rolling.

Paper can be formed by stacking the fiber to ensure its orientation either randomly on one mesh conveyor, or between two mesh conveyors continuously moved on a paper machine while removing the bulk of the water used for dilution until the dry solids content is (usually) ranging from 12% to 35%.

The formed primary fiber web is dried in one or more stages by using mechanical and thermal means until the final dry solids content is (usually) from about 93% to 97%. In the case of the manufacture of thin paper, a creping process follows this step, which significantly affects the properties of the finished thin paper in conventional processes. A typical dry creping process involves creping on a drying cylinder (the so-called Yankee cylinder), typically having a diameter of 4.0 m to 6.5 m, by using a creping scraper with the aforementioned final dry solids content in the raw tissue paper. The wet creping process may also be used if lower requirements are imposed on the quality of the thin paper. The creped, finally dried raw tissue paper (so-called base tissue paper) can then be further processed into a paper product to produce tissue paper.

Instead of the usual thin paper manufacturing process described above, a modified technology can be used according to which an improvement in the specific volume parameter is achieved by applying a special type of drying, which leads to an improvement in the volume softness parameter of the thin paper. This process (there are several different subspecies) is called the technology of “drying by suction of hot air” (SPPV). It is characterized in that the “primary” fibrous web produced after the steps of forming and preparing the paper web is pre-dried to a dry solids content of about 80% before final contact drying on the Yankee cylinder by blowing hot air through the fibrous web. The fibrous web is supported on an air-permeable mesh conveyor, or tape, or on a cloth for SPGV, and during transportation it is directed to the surface of a breathable rotatable cylinder (drum), the so-called cylinder for SPGV. Due to the structuring of the supporting mesh conveyor, or tape, it is possible to produce any pattern from compressed zones that are violated by deformation in the wet state, also called “molding”, resulting in an increase in average specific volumes and, consequently, in an increase in volume softness without a significant reduction the strength of the fibrous web.

To produce multilayer products from tissue paper, such as handkerchiefs, toilet paper, towels or household towels, an intermediate step is often performed, including the so-called “duplication”, in which base tissue paper with the desired number of layers in the finished product is usually rolled into a common multilayer source roll.

The stage of processing base thin paper already rolled up (optionally) into several layers into a finished product of thin paper is carried out on processing machines (converting machines), which perform operations such as, for example, rolling out base thin paper, re-smoothing thin paper embossing by printing, to a certain extent connected with the application of glue over the entire area and / or locally for gluing the individual layers to be joined together, as well as cutting in the longitudinal direction enii, folding, cutting in the transverse direction, folding and adding together a plurality of individual layers of tissue paper and packaging, as well as adding them together to form larger packages or packs covered. Such processing steps may also include the use of substances like perfumes, lotions, emollients or other chemical additives. The individual webs of the paper layers can also be pre-embossed and then joined at the point of contact between the shafts according to the embossing methods known in the art. Any embossing method may result in embossed elements, all of which are of the same height, or in embossed elements having different heights. Bonding layers, for example, by mechanical or chemical means is another group of well-known methods, mainly used for the manufacture of handkerchiefs, diapers and toilet paper.

A well-known technology for increasing the thickness of a paper product is to emboss a paper web. The embossing process is carried out in the contact zone between the embossing shaft and the support shaft. The embossing shaft may comprise protrusions on its peripheral surface, by means of which the so-called “embossed recesses” are formed in the paper web, or the shaft may comprise recesses in its peripheral surface, by which the so-called “embossed protrusions” in the paper web are formed.

The support shafts may be softer than the corresponding embossing shafts, and may consist of rubber, for example natural rubber, or plastic materials, paper or steel.

For the manufacture of multilayer products from tissue paper, especially toilet paper and household tissue paper, three manufacturing methods have been created, including embossing and bonding the layers by gluing. These include embossing methods: “Goffra Incolla / dots”, “double embossing, one lamination / nests” (DTOL) and “protrusion to the protrusion” / “leg to leg”.

In the first manufacturing method mentioned, Goffra Incolla, the first web is guided through the contact zone between the embossing roll and the support roll. In this contact area, the web is provided with an embossed pattern. Then glue is applied to the parts of the first web where the protruding embossing elements are located on the embossing shaft. The glue is transferred from the glue bath using a shaft to transfer glue to the application shaft. The second web is brought to the first web and fastened by gluing to the first web in the contact zone between the so-called contact shaft and the embossing shaft. Bonding with glue takes place at the points on which the glue was applied.

The second manufacturing method (DTOL / nests) is very similar to the Goffra Incolla method described above. According to this method, an additional pair of shafts is used, consisting of a second embossing shaft and a second support shaft. An additional pair of shafts is used to emboss the second web before bonding it by bonding with the first web using a contact shaft. Typically, an additional pair of shafts is positioned adjacent to the first pair of shafts and the contact shaft. This proximity is especially important when using the so-called "nesting" method. The nesting method can be considered as a special case of the general DTOL-manufacturing method. To implement the nesting method, the embossed elements of the first embossed shaft and the embossed elements of the second embossed shaft are arranged so that the embossed elements of the first embossed layer and the embossed elements of the second embossed layer enter each other like gear engagement. This serves to achieve mutual stabilization of the two layers. However, in the DTOL-manufacturing method, such a relationship between the embossed elements of the first, upper, layer and the second, lower, layer is not fulfilled. However, in the literature, the term DTOL method is often used as a synonym for the nesting method.

The third manufacturing method (“protrusion to protrusion” / “leg to leg”) is similar to the DTOL method. By means of two pairs of shafts, both layers: the upper layer and the lower layer are embossed, respectively. Glue is applied to the embossed protrusions of the first layer. However, the bonding of the layers is achieved not by means of the contact shaft, as in the DTOL method, but directly by means of the protruding embossing elements of the second embossing shaft. To achieve this, precise control of the width of the contact zone between the first embossing roll and the second embossing roll is required, which is mainly determined by the thickness of each of the two layers (upper layer and lower layer). In addition, the embossing shafts must be designed so that the protruding embossing elements of both shafts face each other. This explains the use of the terms “protrusion to the protrusion” or “leg to leg” to indicate the type of embossing.

All the methods described above have the following common features: the first embossing roll is made of a solid material, usually metal, especially steel, but embossing rolls made of hard rubber or hard plastic materials are also known. Embossing shafts may be male-type shafts containing individual protrusions. In an alternative embodiment, the embossing shaft may be a female shaft with separate embossing recesses. Typical depths of engraved embossed patterns are between 0.4 mm and 2.0 mm.

The support shaft is usually provided with a rubber coating with a hardness of 35 units to 85 units of Shore hardness, on a scale A. However, structured support shafts are also known, especially shafts made of paper, rubber or plastic materials, or steel.

The glue roll is usually also a rubber roll with a smooth smooth peripheral surface, the hardness of the rubber coating of which is between the hardness of the support shaft and the hardness of the contact shaft. The commonly used hardness values of a rubber coating range from 70 units to 85 units of Shore hardness, on a scale A. When choosing rubber, its compatibility with the adhesive to be applied must be ensured.

A device for applying glue, consisting of a shaft for applying, a shaft for transferring glue and a bath with glue, can be made in the form of a so-called device with an immersed shaft, in which a shaft for transferring glue is immersed in a bath with glue, and this glue is transferred, using surface tension and pushing glue out of the glue bath. By adjusting the clearance between the glue transfer shaft and the application shaft, the amount of glue applied can be adjusted. The application shafts may be structured shafts. Recently, shafts for transferring glue have become known, containing certain recesses in their peripheral surface. Such glue transfer rolls are known as anilox rolls. Such a shaft is usually made of ceramic material or steel, or copper and coated with chrome. Excess glue is removed from the surface of the Anilox shaft by a squeegee. The amount of glue is determined by the volume and number of recesses. Alternative embodiments of glue applicators are based on the use of spray equipment (Weko technology).

A second possibility of influencing the amount of glue transferred is to control the difference in the peripheral speeds of the shaft for transferring the glue and the shaft for application. Typically, the glue transfer shaft is rotated at a lower speed than the glue transfer shaft. The peripheral speed of the shaft for transferring glue is usually from 5% to 100% of the first peripheral speed of the shaft for applying glue. The glue bath can be made in the form of a simple bath; devices for applying glue with squeegees can also be made in the form of chambers.

In the embossing technologies “Goffra Incolla / dot” and “DTOL / nests” use an additional roll, the so-called “contact roll”, for laminating the layers. The contact shaft typically has a smooth rubber surface with a hardness of about 90-95 Shore hardness units, on a scale A. A suitable material is, for example, acrylonitrile butadiene rubber (NBR). However, contact shafts are also known, which, in addition to the rubber coating, are provided with a steel coating. Such a steel coating is often in the form of a steel tape spirally wound over a rubber coating.

In the case where the single layers are separately or together subjected to preliminary embossing, a so-called device for preliminary embossing of microprotrusions is used. This pre-embossing device is often used in conjunction with Goffra Incolla technology. Also commonly used is printing on a tissue paper product before or after the layer bonding step. Technological options are also known, including the use of chemicals, especially lotions and emollients.

Another well-known embossing device comprises a steel embossing shaft and a corresponding supporting steel shaft (for the so-called Union embossing). The surfaces of these shafts are made in such a way that paper deformation and mechanical bonding of the layers are ensured without the use of adhesives by means of one-step embossing.

When using all three of the embossing methods described above, it is useful to provide control of the web tension both before and after bonding the layers, since the physical properties of the web and especially the load-stretch characteristic can change significantly at the embossing stage.

In FIG. 11a shows a portion of the peripheral surface of the embossing shaft 100 containing discrete protrusions 102, using which together with the pliable support shaft described above, the product shown in FIG. 11b. Such a paper product 110 comprises a main part lying in the base plane 112, from which the embossed recesses 114 protrude. In the example according to the prototype, as shown in FIG. 11a, 11b, the embossing shaft comprises protruding embossing elements 102 that (all) have the same height and shape. However, stamping methods of the so-called “double” height are also known. For an example of such embossing, a portion of the outer peripheral surface of the embossing shaft 120 (see FIG. 12a) with protrusions of the male type in two different kinds is shown. These are protrusions 122 having a greater height, as well as protrusions 124 of a lower height. As for the rest, in the example of FIG. 12a, the protrusions have the same cross-sectional shape. However, methods for combining embossing protrusions of various shapes and different heights are also known in the art. Such embossing devices are known from European patent EP 0797705A1.

The resulting paper product 130 is shown schematically in FIG. 12b. Starting from the base plane 132, the paper product contains embossed recesses 134 of greater depth, as well as embossed recesses 136 of a smaller size.

The embossing shafts used in the prototype were mainly manufactured using the so-called moletage technology, which consists in engraving the shaft by cold forming steel on the embossing shaft. According to such moletage technology, usually several stages of cold forming and several stages of etching should be carried out. With such a known manufacturing technology, some restrictions were imposed on the shape of the protrusions on the shaft surface. The angle of inclination had a detrimental effect on the mechanical stability of a paper product made using such an embossing roll. If the angle of inclination is less, then the product has less local stability around the embossed structure, since the locally fibrous structure is destroyed to a greater extent. Thus, for reasons consisting in ensuring sufficient mechanical stability of the paper product and in the limitations imposed by the possibility of manufacturing protrusions on the shaft surface using moletage technology, an inclination angle of at least 23 ° was usually used in the art.

Another engraving technology for making embossing rolls for producing toilet and hygiene paper is etching. In the first stage, a masking coating is applied to the peripheral surface of the embossing roll, followed by a second stage in which the surface is etched by applying acid to areas where no masking coating has been applied. The result is a partially engraved peripheral surface of the shaft, where the transition between the engraved areas and the non-engraved areas contains a step with an angle from 0 ° to 10 °. In other words, etching technology results in a stepped surface structure. The steps of applying a masking coating and etching using the same or different forms of masking coatings can be repeated several times. By using re-etching technology, a surface structure similar to discrete steps extending from the initial peripheral surface of the shaft deep into the shaft material can be obtained.

Another technology for manufacturing embossing shafts for producing toilet and hygienic paper is milling on a CNC machine tool (CNC-computer numerical control). This technology is often used to produce simpler rectangular elements, such as truncated pyramids. The angle of the embossing elements and the radial direction of the embossing shaft can be easily varied over a wide range if such an angle is the same for all embossing elements.

Another technology, mainly used for processing shafts made of plastic materials like rubber shafts, is the use of laser ablation. Laser technology is used for processing shafts made of plastic materials, as well as for processing steel shafts. Other methods of processing embossing rolls are technologies for manual engraving or galvanography. In principle, a combination of these technologies can be used to make embossing rolls. One preferred manufacturing method is based on masking and etching technology combined with moletage technology. Another well-known combination of engraving technologies is the combination of multi-stage etching technology with at least five (preferably about 10) individual etching stages, and the final rounding of the resulting steps to obtain a smoothed shape of the created embossing elements. Suitable rounding steps are metal brushing steps, a short-term general etching step, or a step of spraying solid particles, such as glass, sand or corundum (emery).

Embossing serves not only to give bulk to the fibrous product, but also to give the product a visually enhanced appearance. The visually perceived appearance of the product is important to the consumer of the products, and also serves to provide a higher degree of product recognition. The visually perceived appearance can be improved by a combination of embossing and dyeing steps. Another reason for embossing is to provide a higher ability to absorb or improve perceived softness.

SUMMARY OF THE INVENTION

, is the creation of an embossing roll, a fibrous product, and also a device and method that use such an embossing roll to produce such a fibrous product using new embossing technology to expand the ability to obtain products with visually different appearance.

This problem is solved through the use of: embossing shaft with the hallmarks of claim 1; a method of manufacturing a multilayer fibrous product having the hallmarks of claim 11; devices for the manufacture of a fibrous product having the hallmarks of claim 18; and the fibrous product of claim 23. Preferred embodiments are disclosed in the dependent claims.

According to the invention, the embossing shaft for the manufacture of fibrous products, especially tissue products (“tissue” paper), nonwovens or hybrids thereof, and preferably hygienic and cleaning products, comprises a structured embossing surface suitable for interaction with a support roll, where the structured embossing the surface comprises protrusions of the male type or recesses of the female type starting from the base peripheral surface of the shaft. The embossing pattern is characterized by the following features:

the base areas of the selected protrusions of the male type or the recesses of the male type in the base surface are different;

the heights of the selected protrusions of the male type or the depths of the selected recesses of the male type in the radial direction of the shaft, starting from the base peripheral surface, are different; and

the angles between the side wall portions and the adjacent base peripheral surface of the selected protrusions of the male type and / or the recesses of the female type are different.

Embossed indentations in the product similar to depressed spots are formed by the protrusions of the embossed shaft type covered, whereas embossed protrusions in the fibrous product, especially of a pillow-shaped shape, are formed by means of recesses of the female type in the shaft. Ideally, the correlation between the embossing shaft proposed in the invention and the fibrous product obtained using such an embossing shaft on a device containing such a shaft and a supporting shaft interacting with it leads to a fibrous product with a mirror image in comparison with the shape of the embossing shaft proposed in the invention . However, in reality there are deviations occurring during the manufacturing process. Such deviations can be explained by the fact that the fibrous product during processing has viscoelastic properties, i.e. during stamping, a certain proportion of deformation is elastic deformation. Thus, after the embossing step, there is some reverse process of seating the fibrous product, as a result of which the embossed product does not take the form of a mirror image of the embossing roll. The degree of deviation depends on the material of the fibrous product, the characteristics of the embossing shaft and the support shaft, and many other factors, but mainly depends on the shape of the embossing pattern made on the peripheral surface of the embossing shaft.

The fibrous product according to the invention is mainly a product of tissue paper, non-woven material or a combination thereof, and preferably a hygienic and cleaning product. It contains at least one embossed pattern layer containing embossed recesses similar to depressions or embossed cushioned protrusions, where the embossed recesses or embossed protrusions start from the base plane of the layer. The embossing pattern is characterized by the same basic features that can be found on the embossing shaft, however, in the form of a reverse product pattern and with the above deviations:

the base areas of the selected embossed elements, in particular the embossed recesses or the embossed protrusions, in the base plane are different;

the depths of the selected embossed indentations or the heights of the selected embossed protrusions perpendicular to the base plane are different; and

the angles between the side wall portions of the selected embossed recesses or embossed protrusions and the adjacent base plane are different.

The term “nonwoven material” according to ISO 9092, DIN EN 29092 refers to a wide range of products that, in terms of their properties, are between paper (DIN 6730, Mo 1996) and cardboard (DIN 6730), on the one hand, and textile materials, on the other hand (ISO - International Organization for Standardization; DIN - German Industrial Standard). As for non-woven materials, it is known that a large number of very different manufacturing technologies are used, for example, aerodynamic formation technology and spunlace, as well as wet formation technology. Non-woven materials include mats, non-woven materials and finished products made from them. Non-woven materials can also be called textile-like composite materials, which are flexible porous textile materials that cannot be produced using classical methods of weaving warp and weft threads or knitting methods. In fact, nonwovens are made by mixing, bonding, or gluing fibers together, or by a combination of these methods. The nonwoven material can be made from natural fibers, for example cellulose or cotton fibers, but it can also consist of synthetic fibers, for example polyethylene (PE), polypropylene (PP), polyurethane (PU), polyester, fibers based on polyethylene terephthalate, polyvinyl alcohol, nylon or regenerated cellulose, or a mixture of various fibers. The fiber can, for example, be presented in the form of continuous filaments or prefabricated fibers of finite length, for example synthetic fibers or staple fibers. Non-woven materials, as mentioned herein, can thus be composed of mixtures of synthetic and cellulosic fibrous materials, for example, natural plant fibers (see ISO 9092, DIN EN 29092).

The terms “hygiene products” and “cleaning products”, as used herein, mean toilet paper, household towels, handkerchiefs, face wipes, diapers, wipes and cleaning products also for tableware. The term does not include wallpaper.

For the manufacture of the fibrous product according to the invention, a highly embossed embossing pattern can be used in a highly variable manner. The embossing pattern may contain both embossed protrusions and embossed recesses, as explained above. The embossing pattern is a loosely formed three-dimensional shape. This means that there are no longer standardized forms of embossed protrusions or recesses, or at least there are no more groups of embossed protrusions or embossed recesses, all of which have the same shape. This is an easy requirement that not all embossed grooves (in the case of using an embossing roll with embossed protrusions of the male type) or embossed protrusions (in the case of using an embossing roll with embossing grooves in female type) are the same, leading to the above-mentioned features of the paper product .

Depending on whether the embossing shaft contains protrusions of the male type or recesses of the female type on its peripheral surface, a reference plane comparable to reference plane 112 and 132 (see FIG. 11b and FIG. 12b) can be determined in the examples relating to prototype.

According to the invention, a freely executed three-dimensional surface structure of the embossing shaft is broadcast to the claimed fibrous product. However, as described above, all embossing processes contain such deviations that the embossed product does not take the exact mirror image of the embossing roll. These deviations lead to the appearance of angles in the embossed elements of the product, not as steep as the corresponding angles on the embossing shaft. This general observation is also valid for the three-dimensional embossing proposed in the invention, which should be taken into account when designing a suitable embossing roll for manufacturing the fibrous product of the invention. Deviations of the embossed pattern in the product from the embossed pattern on the shaft depend on the properties of the paper product material, the hardness of the support shaft interacting with the embossing shaft, the pressure per unit length of the embossing shaft forming during the embossing process, and the ratio of the depth, width or angles of a particular embossing element.

A device for the manufacture of fibrous products containing at least one layer, especially products of tissue paper, non-woven material or hybrids from them, and preferably hygienic and cleaning products, contains the embossing shaft proposed in the invention, as well as the supporting shaft interacting with it . The structured embossing shaft has a three-dimensional surface with embossing elements in the form of protrusions of the male type or recesses of the female type; the angles and heights / depths of the selected embossing elements are different. In other words, the embossing roll proposed in the invention is the central object of the device for manufacturing fibrous products according to the invention. The reference to the selected embossed elements is a clear statement that not all embossed elements must have a different shape. For practical reasons, this is not possible, since the embossing shaft usually contains a repeating pattern on its outer peripheral surface, made in such a way that, at least in each of the repeating design sections, the corresponding embossing elements are the same. However, it is also possible that in one single design drawing transferred onto one toilet paper sheet or one household towel sheet, there would be a plurality of individual embossing elements of the same shape. Thus, the above reference to the fact that the embossed elements are different is intended to determine that when using the shaft proposed in the invention, the product proposed in the invention, as well as the device proposed in the invention where such a shaft is used, it is possible to select a wide range of different shapes of individual embossed elements in relation to their size, height / depth, angles and overall shape.

The inventive method of manufacturing a multilayer fibrous product, especially a product of tissue paper, nonwoven fabric or hybrids thereof, and preferably a hygienic and cleaning product, includes the steps of: embossing the top layer using an embossing roll according to the invention; supplying at least one additional layer and bonding together the top layer and the additional layer in the contact zone between the embossing shaft and the contact shaft or in the contact zone between the embossing shaft and the second embossing shaft to emboss the additional layer. When applying this method, it is possible to obtain proposed in the invention three-dimensional fibrous product.

Preferably, the embossing shaft according to the invention is characterized by the presence of angles β ₁ , β ₂ defined as the intersection angles of the orthogonal directions (O _l , O ₂ ) to the surfaces of the protrusions of the male type or the recesses of the female type starting from the selected position on the local surface of the protrusions of the male type or the grooves of the female type with a basic peripheral surface, where such angles β ₁ , β ₂ should be either more than 30 °, preferably more than 50 °, or such angles β ₁ , β ₂ should be less than 20 °.

According to a preferred embodiment, the embossing shaft is configured so that the local surface of at least one female recess is curved so that two orthogonal directions starting from selected positions on the curved local surface can be determined where two orthogonal directions intersect the base peripheral surface at angles β ₁ , β ₂ satisfying the equation 30 ° <| β ₁ -β ₂ | <90 °, and preferably, the equation 50 ° <| β ₁ -β ₂ | <90 °.

By means of such an embossing shaft, a wide range of possible surface shapes including curved recesses can be provided. According to the prototype, standard embossing protrusions may also contain very small rounded sections within 0.1 mm at their edges. Such rounded sections are not covered by the above distinguishing features, according to which the recesses of the enclosing type are curved. What is meant by this is a curved surface that clearly exceeds the locally located rounded edges, as are known and have taken place in the embossing protrusions in the prototype.

Preferably, the structured embossed surface is a loosely formed three-dimensional surface. What is meant by a freely formed dimensional surface is a surface structure that is not a conventional embossing protrusion or embossing recess on / in the base surface, the upper surface and a fixed angle of inclination. Ordinary elements are any embossed elements, which are truncated cones or pyramids with polygonal or round, or oval base areas, cylinders with polygonal or round, or oval base areas, linear elements with a fixed angle, elements with a base area that is round, ellipse or which is a regular polygon with curved side surfaces. Such conventional embossing elements typically have a maximum length in the basal plane of not more than 4 mm. All such ordinary elements are not covered by the above term “freely formed three-dimensional surface”.

According to a preferred embodiment, at least one protrusion of the male type or one recess of the female type has a transverse length exceeding 4 mm, preferably exceeding 10 mm, and most preferably exceeding 25 mm. In other words, the structured embossing surface of the embossing roll according to the invention comprises at least one embossing member having a length exceeding that of a conventional member, typically having a maximum length in the base plane of less than 4 mm.

Preferably, the protrusions of the male type or the recesses of the female type are characterized in that they have a height of the protrusions of the male type or a depth of the recesses of the female type of at least 0.4 mm, especially at least 0.9 mm. The maximum height of the protrusions of the male type and the maximum depth of the recesses of the male type should not exceed 2.0 mm, preferably 1.0 mm.

According to a preferred embodiment, the at least one protrusion of the male type or one recess of the male type has side walls with at least two different angles between the sections of the side wall and the sections of the adjacent base surface. This serves as an additional distinguishing feature of the embossing shaft embossing pattern proposed in the invention. Any common signs regarding shape, regularity, including tilt angles and the overall shape of the embossed elements, are eliminated.

Preferably, at least one female recess is an elongated groove, the depth of which continuously changes in at least a section of the groove in the longitudinal direction of the groove. This is also an additional distinguishing feature that contributes to a very wide variety of possible forms of embossing elements of the embossing roll proposed in the invention. In addition, at least one female recess, being an elongated groove, may preferably have a width continuously changing in the longitudinal direction of the groove in at least a section of the groove. This distinguishing feature, especially in combination with the above feature, which consists in changing the depth of the elongated groove, leads to very great variability in the possibilities of creating forms of embossed protrusions in the product, which are obtained as a result of using elongated recesses in the embossing shaft proposed in the invention.

According to a preferred embodiment, the embossing shaft comprises at least two female grooves, where two female grooves have different ratios between the maximum depth in the radial direction starting from the base peripheral surface and the opening area in the base peripheral surface. By providing such differing ratios of the openings, the optional capabilities of providing significantly different forms of individual embossed protrusions are further increased. However, it should be noted that there are technical limitations regarding the free choice of the ratio of the opening characteristics, since, depending on the properties of the material of the fibrous product, the device for manufacturing the product and the process conditions, the fibrous product to be manufactured can take only that form of such embossing protrusions or embossed recesses that the material may follow. Nevertheless, the use of a number of different ratios of opening features opens up an additional opportunity for the free choice of three-dimensional forms, while preserving the standardized properties and shapes of ordinary embossing protrusions.

According to a further preferred embodiment of the invention, the shaft comprises at least one additional base peripheral surface from which the protrusions of the male type or recesses of the female type start or end. In other words, embossed forms (embossed protrusions of the male type or embossed recesses of the female type) need not begin from the same base peripheral surface of the embossing shaft. Instead, a loosely formed three-dimensional shape may comprise, for example, large recesses of the enclosing type with an internal structure including intermediate sections of lesser depth, by means of which one large recess of the enclosing type is divided into many separate subformations. An example of such an embossing roll according to the invention, in which two different reference planes can be defined, is given below with reference to a preferred embodiment.

According to a preferred embodiment, the at least one protrusion of the male type is an elongated shoulder, the height of which is continuously changing in at least a section of the shoulder in the longitudinal direction of the shoulder.

According to a further preferred embodiment, at least one protrusion of the male type is an elongated collar, the width of which continuously changes in the longitudinal direction of the collar of at least the collar section. Both of the above features, which can be carried out separately or in combination in each protrusion of the male type, which is an elongated shoulder, additionally serve to increase the variability of the possible shapes and visual appearance of the fibrous product embossed using such an embossing roll.

According to a preferred embodiment of the invention, the selected angles between the sections of the side wall of the protrusions of the male type or the recesses of the female type and the adjacent base peripheral surface exceed 30 ⁰ . Using a wide variety of such tilt angles opens up the optional possibility of providing a wider selection of different angles in any one embossing element (male protrusion or female recess) or providing more visible differences between different embossing elements.

Preferably, the embossing roll is made of metal, especially steel or hard plastic materials, or hard rubber. In the case of plastics, a very hard plastic material is preferred; alternatively, rubber is also possible.

Preferably, the embossing surface is formed using master etching and / or moletage processing. The process of applying a masking coating is often performed using a jet of wax or partially removing the masking coating with a laser. Using such processing technologies, a wide variety of surface shapes can be provided, but moletage processing is mainly used in combination with etching technology, which is used when the metal after the moletage processing stage has been most severely deformed.

In an alternative embodiment, the embossing surface of the embossing roll according to the invention can also be formed by machining, especially milling, which, however, can also be performed in addition to masking and etching and / or moletage processing. With these manufacturing techniques, it is possible to freely form the embossed surface of the embossing shaft so that the restrictions imposed on the free form of the embossing shaft are not the shape of the shaft itself, but the use of the form that the fibrous product proposed in the invention can still essentially take during implementation embossing process.

A preferred embodiment of the inventive method for manufacturing a multilayer fibrous product is the bonding together of the upper layer and the additional layer by mechanical bonding of the layers. Such mechanical bonding of the layers, which can be carried out, for example, by means of embossing the edges and / or by rolling, can be carried out either without the use of glue, or in addition to applying glue. If mechanical bonding of layers is used without the use of glue, then the resulting product can maintain a high degree of softness, since the layers are only interconnected in places where mechanical bonding of the layers was performed. In the case of mechanical bonding of the layers, in addition to laminating together the top layer and the additional layer by means of glue, any desired combination of methods of bonding the layers and a set of distinctive properties of the multilayer product, determined by the effect of bonding using glue, can be freely selected.

For laminating together single layers of material, various types of glue can be used. Suitable adhesives include, but are not limited to, starch or modified starch adhesives, such as, for example, methyl cellulose or carboxylated methyl cellulose, and synthetic resin polymers acting as adhesives, rubber, polypropylene, polyisobutylene, polyurethane, polyacrylates, polyvinyl acetate or polyvinyl alcohol. Such adhesives may also contain colorants to improve the visual appearance of the finished products. Often, water-based adhesives are used to laminate paper layers.

In a preferred embodiment of the method comprising laminating together the top layer and the additional layer by using glue, the glue is applied to the protruding parts of the embossing shaft. This glue application technology can be used in conjunction with all of the predominantly used manufacturing techniques, such as Goffra Incolla type processing, lamination of two layers of protrusion to protrusion and technology using an embossing device on which two layers are joined using a nesting method. In an attempt to influence the behavior of the multilayer fibrous product with respect to its mechanical properties, they tried to apply glue selectively to certain protrusions of the embossing shaft. In other words, the adhesive was not applied to all the protrusions, but only in the selected sections of the embossing shaft so that it was possible to vary in a wide range the total ratio of the surface area on which the adhesive was applied relative to the total surface area.

According to a preferred embodiment of the method of the invention, the method further includes the use of colored glue or non-adhesive colored substances to color the top layer, preferably on the side that faces at least one additional layer in the finished product. The application of this stage of the method allows to further increase the great variability of the possible visual effects achieved in a multilayer product. You can freely combine the use of colored substances directed to printed surfaces and / or the use of colored glue in a three-dimensional embossed layer. Preferably, such colored substances are applied by directing them inside the multilayer product so that the colored substances only shine through the upper and / or lower layer to create a visually attractive effect.

According to a further preferred embodiment of the invention, the method according to the invention further includes the step of pre-embossing the additional layer before directing it into the contact zone between the embossing shaft and the contact shaft. This pre-embossing step mainly serves to form microprotrusions, leading to the development of a background pattern on an additional layer of the multilayer fibrous product. The surface density of the elements for embossing microprotrusions is more than 20 / cm ² , since when the surface density of the embossing elements is less than 20 / cm ² , these elements are considered here as macroprotrusions.

As for the temperature at which the process is carried out, either room temperature can be used, or thermal stamping can be used. The use of thermal embossing technology serves to embody complex shapes and, therefore, is difficult to implement for a given fibrous product, especially for a nonwoven material or combination of products. In other words, the use of heat may be useful for embodying very difficult embossing forms in the product of the invention. In addition, thermal embossing can increase the stability of the embossed form.

Preferably, the embossing is carried out in the contact zone between the embossing shaft and the support shaft. However, according to an alternative preferred embodiment, embossing can also be performed using ultrasonic embossing technology.

According to a preferred embodiment of the invention, the top layer and at least one additional layer are folded together in a protrusion to protrusion manufacturing method. In other words, at least one additional layer is also embossed using a similar or the same three-dimensional embossing roll so that the embossed recesses of the upper layer and at least one additional layer that are in contact with each other can be laminated together on the principle of "protrusion to the protrusion." It is assumed that the action of the embossing rolls for processing the top layer and the supply of at least one additional layer are combined so that a well-defined and reproducible effect is obtained.

In an alternative preferred embodiment of the method, the top layer and at least one additional layer are folded together so that they assume a nesting arrangement. It is also required that the action of the embossing rolls for processing the top layer and the supply of at least one additional layer be combined in such a way that a well-defined nesting arrangement of the layers once stacked together is obtained.

According to a preferred embodiment of the method of the invention, the multilayer product comprises three layers, where the upper layer and the lower layer are embossed using the embossing roll according to the invention, while the middle layer is an embossed layer. The technology for bulk embossing conventional products is known from document WO2002 / 103112, the essence of which is incorporated herein by reference. The embossed middle layer serves to impart a greater volume to the product and may be suitable if a product is desired that would produce a large volume sensation.

Proposed in the invention a device for the manufacture of fibrous products contains proposed in the invention embossing shaft and interacts with the support shaft. The support shaft is preferably made of rubber, such as rubber based on a copolymer of ethylene, propylene and diene monomer (EPDM) or acrylonitrile butadiene rubber (NBR), paper or steel.

According to a preferred embodiment of the invention, the support shaft has a hardness in the range from 20 Shore hardness units, on A scale, to 85 Shore hardness units, on A scale, preferably in the range from 35 Shore hardness units, on scale A, to 60 units Shore hardness, on A scale, and most preferably, hardness of about 45 Shore hardness units, on scale A.

A preferred device comprises a pre-embossing device for processing at least one additional layer constituting the wrong layer. Such preliminary embossing is carried out before the direction of the additional layer into the contact zone between the embossing shaft and the contact shaft.

The device according to the invention may further comprise a device located adjacent to the embossing shaft for applying glue to the top layer. Such a device for applying glue is arranged so that the top layer during processing can be placed near the embossing shaft, and so that it is in contact with a conventional device for applying glue on the side of the upper layer that is not in contact with the embossing shaft .

The device preferably comprises a contact shaft rotated in contact with the embossing shaft for bonding together at least one top layer and at least one additional layer. Such a contact roll is used in a conventional Goffra Incolla process and in an embossing machine to provide a nesting arrangement of two embossed layers. However, the contact shaft is not necessary in the case of direct bonding together of two embossed layers for the implementation of the above-described process of bonding the layers "protrusion to the protrusion", in which the vertices of the embossed patterns of the two layers are facing each other and they are laminated together at the contact points of such vertices. In such a case, the device preferably comprises an additional embossing shaft rotated in contact with the embossing shaft according to the invention for embossing at least one additional layer. This additional embossing shaft may also be the inventive embossing shaft. However, you can also use the usual embossing roll, which form the usual embossed elements in the back layer so that they are located in selected positions relative to the inventive embossing roll, which process the top layer, where the tops of the embossed elements created using both embossing rolls were facing each other to achieve the location of the "protrusion to the protrusion" and the fastening of the two layers.

According to a preferred embodiment of the invention, the embossed pattern of the fibrous product, which may also be a single layer product, has additional features in that the embossed protrusions or embossed recesses have a different ratio between the height in the direction perpendicular to the base plane and the area aperture in the base plane. By providing such differing ratios characterizing the openings, they further increase the optional ability to create consciously different shapes for individual embossed elements (embossed protrusions or embossed indentations). However, there are technical limitations regarding the free choice of ratios characterizing the openings, since, depending on the properties of the material of the paper product, the device for manufacturing the product and the process conditions, the paper product to be manufactured can only be given the shape of such embossing protrusions or embossed grooves that he can take.

Preferably, the at least one layer of the fibrous product comprises at least one additional base plane from which such selected embossed protrusions or embossed recesses protrude. In other words, embossed shapes do not have to start from the same base plane. Instead, a freely formed three-dimensional shape may comprise, for example, large embossed protrusions with an internal structure including intermediate sections of lower height, by means of which one large protrusion is divided into many separate subformations.

Preferably, the fibrous product further comprises at least one additional layer constituting a back layer. Such a backing layer may remain un embossed or, in an alternative embodiment, may also contain embossed patterns, or, according to a further alternative embodiment, may contain the same embossing pattern as the top layer. Determining which layer is the top layer and which is the wrong layer is a matter of arbitrary choice. However, for easier recognition, at least one layer with three-dimensional embossing and specially imparted visual appeal is considered to be the top layer of the fibrous product, while at least one additional layer is the wrong layer. However, it is possible to emboss the top layer or top layers together in one contact zone, and the back layer or layers to also emboss together in another contact zone. In addition, the product may also contain one or more middle layers, embossed separately from the upper layer or upper layers and from the back layer or the back layers.

If the backing layer is non-embossed, then such a product is easy to produce, since the non-embossed back layer can be directly fed to the contact shaft, where it can be attached to the upper layer.

According to a preferred embodiment, the back layer is embossed, giving it a second embossing pattern different from the embossing pattern of the top layer, where the second embossing pattern preferably comprises an embossing pattern of microprotrusions. The micro-protrusion embossing pattern is a relatively regular pattern of closely spaced small embossed protrusions. An embossing pattern made with a surface density of embossed elements of more than 20 / cm ² is defined herein as an embossing pattern of microprotrusions. Such an embossing pattern of microprotrusions can be freely selected based on a criterion of functionality, which is to give the paper product certain characteristics regarding overall strength, bulk or smoothness. Requirements for the appearance and effects do not play any significant role in the selection of a suitable pattern for embossing microprotrusions.

Preferably, the plurality of layers are bonded together by gluing, preferably using colored glue. The use of glue is another means of influencing the technical properties of the combined product, especially the overall stiffness of the fibrous product. If colored adhesives are used, then such a choice is made to give a particular visual appearance to the product. According to a preferred embodiment, the proportion of the surface area of the layers coated with the adhesive is more than 5% and less than 80%, preferably from 15% to 60%, especially from 20% to 50%. For standard multilayer paper products with a nesting arrangement of at least two embossed layers, the proportion of the surface area covered with adhesive typically ranges from 3% to 8%. From this comparison with commonly used fractions of the surface area covered with glue, it follows that the product proposed in the invention may contain a much larger fraction of the total surface area covered with glue. With such a large surface area covered by the adhesive, which is preferably from 15% to 60%, a stiff product is obtained which can be particularly suitable for diapers.

To join together multiple layers, and in particular two layers, the layers are preferably bonded by gluing them together in the region of the facing tops of the embossed patterns of the layers.

In another preferred embodiment, the multilayer fibrous product comprises at least one middle embossed layer. The technology for bulk embossing conventional products is known from document W02002 / 103112, the essence of which is incorporated herein by reference. A volume embossed middle layer serves to impart a large volume to the product and may be suitable if a product is desired that would produce a large volume sensation.

According to a preferred embodiment, the fibrous product comprises four layers, where at least one middle layer is embossed together with an adjacent upper layer.

According to a preferred embodiment of the invention, the upper layer of the fibrous product contains an embossed pattern with embossed cushion protrusions, while the lower layer contains embossed stabilizing elements that protrude inside the cushion protrusions of the upper layer. Such a structure has the advantage that relatively large pillow-shaped protrusions can be provided that are stabilized by stabilizing elements of the back layer or the lower layer. For a more detailed description of the concept of providing stabilizing elements, reference is made to document WO2006 / 136186, the essence of which is incorporated herein by reference. Using embossed stabilizing elements, the three-dimensional structure of the upper layer is supported and flattening of the pillow-shaped protrusions is avoided.

Preferably, at least one layer of the multilayer fibrous product has a color different from the color of another layer or other layers. By providing a selected layer having a different primary color, the visual appearance of the multilayer fibrous product can be further improved visually.

Brief Description of the Drawings

In the drawings:

in FIG. 1 schematically shows a section of the peripheral surface of a structured embossing roll according to the invention for the manufacture of a paper product according to the invention;

in FIG. 2 schematically shows the proposed two-layer product, in which one of its layers is embossed using the embossing shaft, schematically shown in FIG. one;

in FIG. 3 schematically shows a contact zone between two structured embossing shafts of the invention to be used in an embossing machine operating according to the protrusion to protrusion method;

in FIG. 4 shows a cross section of an example product, for the manufacture of which embossing shafts are used, schematically shown in FIG. 3;

in FIG. 5 schematically shows a contact zone between two structured embossing shafts of the invention to be used in an embossing machine operating according to a method for nesting protrusions;

in FIG. 6 shows a cross-section of an example product, for the manufacture of which embossing shafts were used, schematically shown in FIG. 5;

in FIG. 7 schematically shows a curved recess of the female type in the peripheral base surface of the embossing shaft;

in FIG. 8 shows an example of a device for manufacturing a product and for implementing a manufacturing method of the inventive two-layer product using an embossing machine such as Goffra Incolla;

in FIG. 9a shows another example of a device for manufacturing a product and for implementing a manufacturing method of the inventive two-layer product using a protrusion to protrusion embossing machine;

in FIG. 9b shows an additional example of a device for manufacturing a product and for implementing a method for manufacturing a two-layer product of the invention using a protrusion-to-protrusion embossing machine comprising an ink printing apparatus and an adhesive applicator;

in FIG. 10 shows an additional example of a device for manufacturing a product and for implementing a method for manufacturing a two-layer product of the invention using an embossing machine for nesting protrusions;

in FIG. 11a is a schematic view of a portion of a conventional embossing shaft with one height of male protrusions;

in FIG. 11b is a schematic view of a product embossed using an embossing shaft with a single protrusion height shown in FIG. 11a;

in FIG. 12a is a schematic view of a portion of the peripheral surface of a conventional embossing shaft with protrusions of two heights; and

in FIG. 12b shows a product embossed using a conventional embossing roll with two elevation protrusions shown in FIG. 11b.

Description of preferred embodiments of the invention

In FIG. 1 is a schematic view showing only a small portion of the peripheral part of the embossing shaft for the manufacture of the paper product of the invention. The embossing shaft is preferably made of steel, very hard plastics, rubber or hard rubber, and is generally indicated by the number 10. In a specific embodiment, as shown in FIG. 1, the embossing shaft 10 comprises embossing formations of the female type, which means that in the outer peripheral surface of the shaft, starting from the peripheral peripheral surface 12 shown by the dashed line, grooves of the female type are made. An additional base peripheral surface 14, indicated by a dotted line with two points, can be defined on the embossing shaft. In addition to the main recesses 16 extending from the base peripheral surface 12, there are also additional smaller recesses 18 starting from the additional peripheral base surface 14 and having a shallower depth than the main recesses 16.

From a comparison of the maximum depths D ₁ and D _{2 of the} two recesses shown in the example in the shaft 10, it follows that the recesses can have different depths. The cross section shown in FIG. 1, it is impossible to judge the extent of the recesses in a direction perpendicular to the plane of the drawing, i.e. in the base surface 12. The same applies to the total dimensions of areas A, shown by way of example, as areas A ₁ and A ₂ in FIG. 1. However, it should be noted that the ratio between the depth D and the corresponding opening area A of the recess of the female type may be different for different recesses 16, as well as for different recesses 18 starting from the second base peripheral surface 14.

In FIG. 1 also shows that the tilt angles between the parts of the sections 17 of the side wall of the recesses 16 and the direction perpendicular to the base peripheral surface 12, i.e. radial direction of the shaft 10, have various and freely selectable values.

The drawing shown as an example, made on the surface of the shaft 10, can be obtained by any known method, for example, by machining, etching, applying a masking coating followed by etching and the moletage method, or using suitable combinations of these methods. The schematic view shown in FIG. 1, is intended to show that the embossed surface can have a freely chosen shape without limitation with respect to the uniformity of the shape of the various embossed recesses 16 or 18. Dimensions, tilts of the side walls, determination of the basic peripheral surfaces and the area of the openings in any base surface defined as Thus, they can be freely selected to the extent that the material to be embossed can essentially take the form of an embossed surface of the shaft.

In FIG. 2 shows a cross-section of an inventive product 60, shown as an example, which is a two-layer product consisting of a first layer 20 and a second layer 30. The first layer 20 is the top layer, and it is made using the technology of the invention of three-dimensional embossing and with using the embossing shaft 10 shown in FIG. 1. The second lower layer 30 is provided with an embossed microprotrusion pattern with a higher surface density of the embossed shapes as compared to the upper layer 20. The micro-embossed patterns have an embossed surface density of more than 20 / cm ² .

The top layer 20 is a three-dimensionally embossed layer in which pillow-shaped protrusions 22 are formed, while the embossed microprotrusions of the back layer 30 are indicated by 32. In the schematic drawing, in FIG. 2, it is shown that several embossed microprotrusions 32 protrude into the embossed pillow-like protrusions 22 of the upper layer 20 and stabilize them, supporting the pillow-shaped protrusions and eliminating their flattening.

In regions 40, the two layers are bonded together with glue 42, which is locally applied to the base plane 24 of the first layer corresponding to the base peripheral surface 12 of the shaft 10 shown in FIG. one.

In the upper layer 20, an additional reference plane corresponding to the additional reference surface 14 of the shaft 10, which corresponds to the additional reference peripheral surface 14 of the shaft 10 shown in FIG. 1, and to which the pillow-shaped protrusions in the secondary pillow-shaped protrusions 41 are subdivided.

The second layer 30 is leveled by a contact process in those areas in which the first layer 20 and the second layer 30 are bonded together by gluing. To enhance the visual effect, glue 42 may be colored.

In FIG. 3 schematically shows a contact zone 11 between two inventive, structured embossing shafts 10a and 10b to be used in an embossing machine, and a protrusion to protrusion manufacturing process is illustrated. To implement this process, two shafts 10a and 10b are used for three-dimensional embossing having surface topographies that are mirror images of each other. In fact, in order to achieve an arrangement of two layers corresponding to the protrusion to protrusion mode, it is not necessary that the embossing surfaces of the two interacting embossing shafts are the same with respect to their mirror images. It is sufficient that the selected elevated embossed sections of the two interacting shafts face each other. In the example shown in FIG. 3, both shafts 10a and 10b are provided with female recesses 16, but some additional peripheral surfaces 14, as well as 15 defining additional surfaces and constituting the starting point of additional female recesses 18 and 19 extending from planes 14 and 15, respectively, can be defined . Contact area i.e. the distance between the two reference peripheral planes 12a, 12b is adjusted according to the thickness of the processed fibrous product and, possibly, the thickness of the additional layers comprising one or more middle layers.

In FIG. 4 shows an example of a multilayer product made by using the pair of shafts schematically shown in FIG. 3. The first layer 20 and the second layer 30 repeat the shape of the embossing rolls 10a, 10b; the above-described deviations of the shape of the embossed fiber product from the shape of the embossing roll are not considered here. This deviation is expressed in a small decrease in the height of the embossed elements in a similar product in comparison with the heights of the embossed elements in the embossing roll. There is a third layer 21 (as shown in the drawing), subjected to volume embossing. By volume embossing, it is understood here that the third layer 21 was given an irregular embossing pattern, not combined with the embossing pattern of the first layer 20 and the second layer 30. The effect of using the middle layer 20 subjected to volume embossing is to stabilize the embossed protrusions 22 of the first and second layers 20, 30. The product shown in FIG. 4 is made by separate volume embossing of the middle layer 21 and the subsequent direction of the middle layer into the contact zone 11 between the embossing shafts 10a and 10b, as shown in FIG. 3. In the contact zone 11 between these parts of the embossing rolls lying in the basic peripheral planes 12a, 12b and facing each other, the three layers are fastened together using glue applied to the layer 20 and / or to the layer 30 during the individual steps embossing, but before being directed into the contact zone 11 between the two embossing shafts shown in FIG. 3.

Alternatively, the embossing rolls and product are positioned in the manner shown in FIG. 3 and 4, more than one middle embossed middle layer or an un embossed middle layer can be used. In addition, the shape of the two embossing shafts 10a, 10b may be different, where the embossing surfaces of both shafts are not mirror images of each other. This is possible, since the two shafts act in a coordinated manner and there are clearly defined areas of both shafts in which the layers are bonded in the contact zone 11 between the two embossing shafts 10a, 10b.

The embodiment of FIG. 5 and the resulting product shown in FIG. 6, are distinguished by the fact that two embossing shafts 10a, 10c having different shapes are used here and in that they are arranged so that the layers to be embossed by the individual shafts 10a and 10c can be joined together in an additional process step to achieve a nesting location of layers.

The embossing shaft 10a is identical to the embossing shaft 10a shown in FIG. 3, so that in any subsequent explanation, reference can be made to the description related to FIG. 3. The embossing shaft 10c is provided with discrete protrusions 23, which can either have the same shape or different shape, as in the example of the embossing shaft 10c, in which different types of protrusions 23a, 23b and 23c ... are different from each other. The process in which the embossing shafts 10a and 10c are used is described below with reference to FIG. 10.

By joining together two layers 20 and 30, treated separately on the embossing shafts 10a, 10c, between the first embossing shaft 10a and the contact shaft, the product shown schematically in FIG. 6. The lower layer 30 is provided with protrusions 33 which are inserted into the embossed protrusions 22 of the first layer 20, and with their help provide a stabilizing effect exerted on the protrusions 22 of the first layer 20. This is an advantage, since the embossing shaft 10a according to the invention provides a freely designed a three-dimensional surface with which you can create embossed indentations or embossed protrusions of complex shape and large sizes, which more stably maintain their shape, if the lower layer is equipped with supporting protrusions 33 This is shown schematically in FIG. 6.

In FIG. 7 schematically shows other features of the embossing shaft proposed in the invention. In FIG. 7 shows a small portion of the base peripheral surface of the shaft 10 with a female recess 16 formed therein. The recess of the female type comprises lateral walls of curved shape in cross section, as shown in FIG. 7. The words "curved side walls" mean not only small rounded sections in the transitions between the base peripheral surface and conventional embossed recesses, but also a curved surface, which can make up a significant part or all of the side wall. In FIG. 7 shows two imaginary orthogonal lines starting from the curved surface of a female type recess. Both orthogonal lines intersect the base peripheral surface at angles designated β ₁ and β ₂ , which are defined (each) as the smallest angle existing between the orthogonal direction O ₁ and O ₂ and the base peripheral surface 12 of the embossing shaft 10. You can see what can two orthogonal directions are determined that (both) start from the selected positions of the curved local surface of the female recess and which intersect the base peripheral surface at angles satisfying the equation 30 ° <| β ₁ -β ₂ | <90 °, and preferably the equation 50 ° <| β ₁ -β ₂ | <90 °. It should be noted that the angles β ₁ and β ₁ have a different direction, which leads to different mathematical algebraic signs.

In FIG. 8 shows a first embodiment of a <device> for manufacturing a two-layer product according to the invention using Goffra Incolla technology. In the example shown in FIG. 8, the first layer 20 is embossed three-dimensionally between the support shaft 50 and the inventive embossing shaft 10, as shown by way of example in FIG. 1. Glue is applied to the base surface 12 of the three-dimensional embossing shaft 10 (if the three-dimensional embossing shaft is provided with recesses of the female type, as shown in Fig. 1) or on the upper surfaces of the embossing protrusions of the male type (if the three-dimensional embossing shaft is equipped with protrusions of the male type on its peripheral surface). The glue is applied by means of a device 52 containing a shaft 53 for application. The second layer 30 may be optionally pre-embossed between the micro-embossing shaft 54 and the corresponding support shaft 56, and then fed into the contact zone between the three-dimensional embossing shaft 10 and the contact shaft 58, as is usually done in the art. The two-layer laminated product 60 corresponding to the product shown in FIG. 2 is discharged from the schematic device as shown in FIG. 8.

In FIG. 9a. schematically shows an alternative embodiment of an embossing device and illustrates a method of manufacturing a product on the principle of "protrusion to the protrusion." The first layer 20 is subjected to three-dimensional embossing between the embossing shaft 10 according to the invention and the support shaft 50, and the adhesive is applied by means of a device 52 comprising an application shaft 53. The second layer 30 also provides a three-dimensional embossing pattern between the additional three-dimensional embossing shaft 62 according to the invention and the corresponding support shaft 64. The second three-dimensional embossing shaft may be of the same type as the shaft 10, i.e. both shafts may be provided with protrusions of the male type and / or recesses of the female type, or it may be of another type so that one of the shafts 10, 62 contains recesses of the female type and the other shaft contains protrusions of the male type. The two layers 20 and 30 are joined together in the contact zone between the two embossing shafts 10 and 62 to form a two-layer laminated product 60. The type of embossing device and method shown in FIG. 9a may be of the type shown in FIG. 3 described above.

In FIG. 9b shows an embossing device and illustrates a method of manufacturing a product according to the “protrusion to protrusion” principle, similar to those shown in FIG. 9a, except that the glue applicator 52 is connected to the three-dimensional embossing shaft 62 instead of the shaft 10, and that the additional ink (printing) applicator 72 is connected to the three-dimensional embossing shaft 10.

In FIG. 10 shows a further alternative embodiment of an embossing device, and a method for manufacturing a female type product is illustrated. The first layer 20 is subjected to three-dimensional embossing between the embossing shaft 10 according to the invention and the support shaft 50, and the adhesive is applied by means of a device 52 comprising an application shaft 53. Thus, the processing of the first layer 20 is carried out in the same manner as described above with reference to FIG. 8, 9a and 9b. At least one additional layer 30 is provided with an embossing pattern between the embossing roll 63, which can be either the three-dimensional embossing roll according to the invention or a conventional embossing roll. The second layer 30 is embossed between the shaft 63 and the support shaft 64 until this layer is directed into the contact zone between the three-dimensional embossing shaft 10 for embossing the first layer and the contact shaft 58 cooperating with the three-dimensional embossing shaft 10 for embossing the first layer. The embossing shafts 10 and 63 operate in a coordinated manner so that a nesting arrangement is shown schematically in FIG. 6. The embossing shaft 63 for embossing the at least one additional layer 30 may be of the type shown as an example in the form of the embossing shaft 10c in FIG. 5, but it is possible to use any other form leading to a nesting of the embossed elements of the second layer 30 in the embossed elements of the first layer 20 to provide the desired result.

The use of the embossing roll proposed in the invention in combination with the three-dimensional embossing method and the device makes it possible to produce fibrous products with a much wider variety of embossing patterns in comparison with conventional fibrous products. There are almost no restrictions regarding the shape of individual embossing patterns, except for the requirement that the corresponding fibrous product take the form of three-dimensional embossing rolls during the manufacturing process.

Claims (28)

1. An embossing roll (10) for the manufacture of fibrous products, especially tissue products, nonwovens or hybrids thereof, and preferably hygienic and cleaning products with a structured embossing surface suitable for interaction with a support roll (50), where the structured embossing the surface comprises protrusions of the male type or recesses (16) of the female type, starting from the base peripheral surface (12, 12a, 12b) of the shaft; Where
- the embossing pattern is characterized by the following distinctive features:
- the base area (A ₁ , A ₂ ) of the selected protrusions of the male type or recesses (16) of the female type in the base peripheral surface (12, 12a, 12b) are different;
- the heights or depths (D ₁ D ₂ ) of the selected protrusions of the male type or the recesses (16) of the female type in the radial direction of the shaft (10) starting from the base peripheral surface (12, 12a, 12b) are different; and
- the angles (α ₁ , α ₂ ) between the sections (17) of the side walls and the adjacent base peripheral surface (12, 12a, 12b) of the selected protrusions of the male type and / or recesses (16) of the female type are different;
- at least one protrusion of the male type or one recess (16) of the female type contains side walls (17) with at least two different tilt angles between the sections of the side wall and the adjacent base surface (12, 12a, 12b); and
- the selected angles (α ₁ , α ₂ ) between the sections (17) of the side walls of the protrusions of the male type or the recesses (16) of the female type and the adjacent base surface exceed 30 °. 2. The embossing shaft according to claim 1, in which the angles β ₁ , β ₂ defined as the intersection angles of the orthogonal directions (O ₁ , O ₂ ) starting from the selected positions on the local surface of the protrusions of the male type and / or recesses of the female type, base peripheral surface, where such angles β ₁ , β ₂ should be more than 30 °, preferably more than 50 °, or less than 20 °. 3. The embossing shaft according to claim 1 or 2, in which the local surface of at least one recess (16) of the female type is curved in such a way that two orthogonal directions (O ₁ , O ₂ ) starting from the selected positions can be determined on a local surface where two orthogonal directions (O ₁ , O ₂ ) intersect the basic peripheral surface at angles β ₁ , β ₂ satisfying the equation 30 ° <| β ₁ -β ₂ | <90 °, and preferably the equation 50 ° <| β ₁ -β ₂ | <90 °. 4. The embossing shaft according to claim 1, wherein the structured embossing surface is a freely formed three-dimensional surface. 5. The embossing shaft according to claim 1, in which at least one protrusion of the male type or one recess (16) of the female type has a transverse extension that exceeds 4 mm, preferably 10 mm, and most preferably 25 mm, in which the protrusions the male type have a minimum height of 0.4 mm and a maximum height of 2.0 mm, and in which the recesses of the male type have a minimum depth of 0.4 mm and a maximum depth of 2.0 mm. 6. The embossing shaft according to claim 1, containing at least one female recess (16), which is an oblong groove, the depth of which is continuously changing, at least in the groove section in the longitudinal direction of the groove, or the width of which is continuously changing in the longitudinal the direction of the groove, at least in the section of the groove. 7. The embossing shaft according to claim 1, containing at least one protrusion of the male type, which is an elongated shoulder, the height of which is continuously changing, at least in the section of the shoulder in the longitudinal direction of the shoulder, or the width of which is continuously changing in the longitudinal direction of the shoulder, at least in the shoulder section. 8. The embossing shaft according to claim 1, containing at least two recesses (16) of the female type, where two recesses of the female type have a different ratio between the maximum depths (D ₁ , D ₂ ) in the radial direction starting from the base peripheral surface (12, 12a, 12b), and the area of the openings (A ₁ , A ₂ ) in the base peripheral surface (12, 12a, 12b). 9. The embossing shaft according to claim 1, containing at least one additional base peripheral surface (14, 14a, 14b, 15a, 15b), from which the selected protrusions of the male type or recesses of the female type start. 10. The embossing shaft according to claim 1, the embossing surface of which is made by applying a masking coating-etching, and / or by means of moletation, and / or by machining. 11. A method of manufacturing a multilayer fibrous product, especially a product of tissue paper, non-woven material or a hybrid of them, and preferably a hygienic and cleaning product, comprising the following steps of the method:
(a) embossing the top layer (20) using an embossing roll (10) according to any one of the preceding paragraphs;
(b) supplying at least one additional layer (30), where such an additional layer (30) is not necessarily a pre-embossed layer (54, 56) before being directed into the contact zone between the embossing shaft (10) and the contact shaft (58); and
(c) bonding together the top layer (20) and the additional layer (30) in the contact zone between the embossing shaft (10) and the contact shaft (58) or in the contact zone between the embossing shaft (10) and the second embossing shaft (62) for embossing additional layer (30). 12. The method according to claim 11, in which, in step (c), the bonding is carried out by mechanically bonding the layers or by laminating together the upper layer (20) and the additional layer (30) with adhesives. 13. The method according to item 12, in which the adhesive is applied to the protruding parts of the embossing shaft (10), especially selectively on the special protrusions of the embossing shaft (10). 14. The method according to any one of paragraphs.11-13, further comprising the use of colored glue and / or non-adhesive colored substances for applying dye to the top layer (20), preferably on its side that faces at least one additional layer (30) in the finished product (60). 15. The method according to claim 11, in which
embossing in step (a) is performed using ultrasonic embossing technology in the contact zone between the embossing shaft (10) and the support shaft (50). 16. The method according to claim 11, in which the top layer (20) and at least one additional layer (30) are folded together, arranged on the principle of "protrusion to the protrusion" or nesting method. 17. The method according to claim 11, in which:
- the multilayer product (60) contains three or four layers;
- the lower layer (30) is embossed using the embossing shaft (10) according to any one of claims 1 to 10; and
- at least one middle layer (21) is subjected to volume embossing, in which at least one middle layer is embossed together with the upper layer. 18. A device for the manufacture of fibrous products containing at least one top layer (20), especially products of tissue paper, non-woven material or hybrids from them, and preferably hygienic and cleaning products, containing:
- embossing shaft (10) according to any one of claims 1 to 10; and
- interacting with the support shaft (50) and
- optionally, a device (54, 56) for pre-embossing at least one additional layer (30). 19. The device according to p. 18, further containing a device (52) for applying glue, located near the embossing shaft (10), for applying glue to the top layer (20),
in which such a device for applying adhesives preferably comprises a shaft (53) for applying adhesives, where the shaft (53) for applying may not necessarily be a structured shaft for applying. 20. The device according to any one of claims 18 and 19, further comprising a contact shaft (58) interacting with the embossing shaft (10) for fastening together at least one upper layer (20) and at least one additional layer (thirty). 21. The device according to any one of claims 18 and 19, further comprising an additional embossing shaft (62) interacting with the embossing shaft (10), for embossing at least one additional layer (30). 22. The device according to PP.18 and 19, further comprising:
- an additional embossing shaft (62) interacting with the first embossing shaft (10), for embossing at least one additional layer (30);
- a device (52) for applying adhesives either to the upper layer (20) or to the lower layer (30), where this device (52) for applying adhesives may optionally contain a shaft (53) for applying, especially a structured shaft for applying; and
- a device (72) for applying dye (printing ink) either to the upper layer (20) or to the lower layer (30). 23. The fibrous product (60), especially a product of tissue paper, non-woven material or a hybrid of them, and preferably a hygienic and cleaning product, containing:
at least one embossed pattern layer (20) containing embossed recesses (22) similar to depressed points, or a pillow-shaped embossed protrusion (22), where the embossed recesses or embossed protrusions start from the base plane (24) of the layer (20) );
- embossing pattern, characterized by the following features:
- the base area (A _1, A ₂₎ selected embossed elements (22), in particular, the embossed dimples or embossed projections in a base plane (24) are different;
- the depths (D ₁ , D ₂ ) of the selected embossed recesses or the height of the selected embossed protrusions perpendicular to the base plane (24) are different; and
- the angles (α ₁ , α ₂ ) between the sections of the side wall and the adjacent base plane (24) of the selected embossed indentations or embossed protrusions (22) are different;
- at least one protrusion of the male type or one recess of the male type contains side walls with at least two different angles between the sections of the side wall and the adjacent base surface; and
- the selected angles (α ₁ , α ₂ ) between the sections of the side walls of the protrusions of the male type or the recesses of the female type and the adjacent base surface exceed 30 °. 24. The fibrous product according to item 23, containing the embossing pattern, having additional features:
- the selected embossed protrusions (22) or embossed recesses have a different ratio of height or depth (D ₁ , D ₂ ) in the direction perpendicular to the base plane (24) and the opening area (A ₁ , A ₂ ) in the base plane (24). 25. The fibrous product according to item 23 or 24, in which at least one layer (20) contains at least one additional base plane (25), from which protruded embossed protrusions or embossed recesses (41) protrude. 26. The fibrous product according to claim 23, further comprising at least one additional layer (30) constituting the back layer (30), where the back layer may be an unembossed layer, or where the back layer (30) either contains the same pattern the embossing, like the top layer (20) or the backing layer (30), is embossed with a second embossing pattern, different from the embossing pattern of the upper layer (20), where the second embossing pattern preferably contains a micro-embossing pattern. 27. The fibrous product according to claim 26, wherein the plurality of layers (20, 30) are bonded by gluing together, preferably using colored glue, where the proportion of surface area coated with adhesives between the layers is preferably more than 5% and less than 80%, preferably from 15 to 60%, where a plurality of layers (20, 30) can optionally be bonded by gluing together (40) in the region of the vertices of the embossed patterns of the layers facing each other, and where the layers (20, 30) are preferably only partially bonded together. 28. The fibrous product according to paragraph 24, in which:
- the upper layer (20) contains an embossing pattern with embossed cushion-like protrusions (22); and
- the lower layer (30) contains embossed stabilizing elements (33) protruding into the cushion-like protrusions (22) of the upper layer (20).

Images