1. Field of the invention
[0001] The present invention relates to an apparatus and a method for embossing a multi-ply
paper product to be used in the manufacture of such a product. At least one ply of
the multi-ply paper product has a background embossing, so as to soften the paper
product and bring a web structure to the surface of the paper product, and a decoration
embossing so as to give a more aesthetical impression to the paper product. Thus,
the present invention relates to an apparatus for embossing a multi-ply paper product,
comprising at least one background embossing unit for embossing at least one ply of
the multi-ply paper product and at least one decoration embossing unit for embossing
the at least one ply downstream of the background embossing unit, as seen in the direction
of processing. The paper product is generally formed from a continuous web and may
be made from tissue paper or non-woven material.
[0002] A tissue paper is defined as a soft absorbent paper having a low basis weight. One
generally selects a basis weight of 8 to 30 g/m
2, especially 10 to 25 g/m
2 per ply. The total basis weight of multiple-ply tissue products is preferably equal
to a maximum of 65 g/m
2, more preferably to a maximum of 50 g/m
2. Its density is typically below 0.6 g/cm
3, preferably below 0.30 g/cm
3 and more preferably between 0.08 and 0.20 g/cm
3.
[0003] The production of tissue is distinguished from paper production by the its extremely
low basis weight and its much higher tensile energy absorption index (see DIN EN 12625-4
and DIN EN 12625-5). Paper and tissue paper also differ in general with regard to
the modulus of elasticity that characterizes the stress-strain properties of these
planar products as a material parameter.
[0004] A tissue's high tensile energy absorption index results from the outer or inner creping.
The former is produced by compression of the paper web adhering to a dry cylinder
as a result of the action of a crepe doctor or in the latter instance as a result
of a difference in speed between two wires ("fabrics"). This causes the still moist,
plastically deformable paper web to be internally broken up by compression and shearing,
thereby rendering it more stretchable under load than an uncreped paper.
[0005] Moist tissue paper webs are usually dried by the so-called Yankee drying, the through
air drying (TAD) or the impulse drying method.
[0006] The fibers contained in the tissue paper are mainly cellulosic fibres, such as pulp
fibers from chemical pulp (e.g. Kraft sulfite and sulfate pulps), mechanical pulp
(e.g. ground wood), thermo mechanical pulp, chemo-mechanical pulp and/or chemo-thermo
mechanical pulp (CTMP). Pulps derived from both deciduous (hardwood) and coniferous
(softwood) can be used. The fibers may also be or include recycled fibers, which may
contain any or all of the above categories. The fibers can be treated with additives
- such as fillers, softeners, such as quaternary ammonium compounds and binders, such
as conventional dry-strength agents or wet-strength agents used to facilitate the
original paper making or to adjust the properties thereof. The tissue paper may also
contain other types of fibers, e.g. regenerated cellulosic fibres or synthetic fibers
enhancing, for instance, strength, absorption, smoothness or softness of the paper.
[0007] Tissue paper may be converted to the final tissue product in many ways, for example,
by embossing or laminating it into a multi-ply product, rolled or folded.
[0008] The term non-woven (ISO 9092, DIN EN 29092) is applied to a wide range of products
which, in terms of their properties, are located between those of paper (cf. DIN 6730,
May 1996) and cardboard (DIN 6730) on the one hand, and textiles on the other hand.
As regards non-woven a large number of extremely varied production processes are used,
such as the air-laid and spun-laced techniques as well as wet-laid techniques. The
non- woven includes mats, non-woven fabrics and finished products made thereof. Non-wovens
may also be called textile-like composite materials, which represent flexible porous
fabrics that are not produced by the classic methods of weaving warp and weft or by
looping. In fact, non-wovens are produced by intertwining, cohesive or adhesive bonding
of fibres, or a combination thereof. The non-woven material can be formed of natural
fibres, such as cellulose or cotton fibres, but can also consist of synthetic fibres,
such as Polyethylene (PE), polypropylene (PP), polyurethane (PU), polyester, nylon
or regenerated cellulose, or a mix of different fibres. The fibres may, for example,
be present in the form of endless fibres of pre-fabricated fibres of a finite length,
as synthetic fibres produced in situ, or in the form of staple fibres. The nonwovens
according to the invention may thus consist of mixtures of synthetic and cellulose
fibrous material, e.g. natural vegetable fibres (see ISO 9092, DIN EN 29092).
[0009] Hygiene or wiping products primarily include all kind of dry-creped tissue paper,
wet-creped paper and cellulose or pulp wadding or all kinds of nonwovens, or combinations,
laminates or mixtures thereof. Typical properties of these hygiene and wiping products
include the ready ability to absorb tensile stress energy, their drapability, good
textile-like flexibility, properties which are frequently referred to as bulk softness,
a high surface softness, and a high specific volume with a perceptible thickness.
As high a liquid absorbency as possible and, depending on the application, a suitable
wet and dry strength as well as an appealable visual appearance of the outer product
surface is desired. These properties, among others, allow these hygiene and wiping
products to be used, for example, as cleaning wipes such as paper or non-woven wipes,
windscreen cleaning wipes, industrial wipes, kitchen paper, or the like; as sanitary
products such as for example toilet paper, paper or non-woven handkerchiefs, household
towels, towels, and the like; as cosmetic wipes such as for example facials and as
serviettes or napkins, just to mention some of the products that can be used. Furthermore,
the hygiene and wiping products can be dry, moist, wet or pre-treated in any manner.
In addition, the hygiene and wiping products may be folded, interleaved or individually
placed, stacked or rolled, connected or not, in any suitable manner.
[0010] Due to the above description, the products can be used for personal and household
use as well as commercial and industrial use. They are adapted to absorb fluids, for
decorative purposes, for packaging or even just as supporting material, as is common
for example in medical practices or in hospitals. In terms of their wide variety,
hygiene and wiping products are now considered to be everyday products.
2. Prior art
[0011] In the prior art, multi-ply tissue paper products are known having a decoration embossing
and a micro embossing as background embossing. According to conventional manufacturing
processes, first a micro embossing is applied to the tissue ply/plies and, in a second
step, a decoration embossing is added to the top ply/plies. Subsequently, glue is
applied on the protuberances, to laminate the top ply/plies and the bottom ply/plies
together.
[0012] Such a tissue paper product is, for example, known from
EP-A-0 797 705. The paper product comprises a background embossing pattern in the form of a micro
embossing commonly having a density of between 30 dots/cm
2 and 80 dots/cm
2. However, in such prior art tissue paper products, the pre-micro embossing, i.e.
the background embossing is conducted ahead of the decoration embossing, so that compression
and loss of thickness of the background embossing results during the step of decoration
embossing. In addition, the optical appearance of the tissue paper product is impaired.
[0013] Fig. 1 shows an example of an embossing part of a standard machine for producing
multi-plied decoration embossed products. The embossing part consists, for example,
of two embossing units (1,2), wherein the first embossing unit (1) consists of two
background embossing sections (3) each having a rubber backing roll (5) and a steel
embossing roll (4). These background embossing sections serve for the application
of a micro background embossing to one or more plies of a multi-ply paper product.
In the present case, a two-ply paper product is to be manufactured, each ply being
embossed with a background pattern by the respective embossing unit. The rubber backing
roll and the steel embossing roll form an embossing/backing roll combination (3).
The steel embossing rolls (4) and the rubber rolls (5) are arranged in a way that
an embossing nip of 10 to 30 mm (depending on the roll diameter; in the present case
180 mm) is formed between the rolls and the rubber roll is pressing with a force of
approximately 12.000 N/m against the embossing roll. The rubber rolls conventionally
have a hardness of approximately 50 Shore (A) and the embossing micro pattern (6)
has a density of e.g. 40 dots/cm
2.
[0014] The pre-embossed top ply/plies (7) and the bottom ply/plies (8) are subsequently
transferred to a decoration embossing unit (2) for embossing at least one ply downstream
of the background embossing unit as seen in the direction of processing, i.e. from
the left to the right in the drawing. The decoration embossing unit also comprises
an embossing/backing roll combination (9). The embossing roll may be a steel embossing
roll or a roll covered with hard rubber, e.g., an ebonite covered roll. The decoration
embossing roll (10) has protuberances on its surface, which are design elements distributed
on the roll. The standard engraving depth of the embossing roll (10) is commonly from
1,2 up to at most 1,5 mm. The decoration backing roll (11) with a hardness of about
50 Shore (A) presses on the surface of the decoration embossing roll to create a pressing
area in which the top ply/plies (7) receives the embossment of the design protuberances.
[0015] After embossment of the decoration elements, an adhesive is applied onto the top
of the protuberances which are embossed in the web material. Preferred adhesives are
among others, carboxymethylcellulose(CMC),or special polymerisates, such as polyvinyl
alcohols (PVOH),polyvinyl acetates (PVAc), copolymerisates of ethylene and vinyl acetate(EVA),
copolymerisates of styrene and butadiene, polyurethanes having suitable cross-linking
agents (for instance polyols or polyamines) or polymerisates on the basis of acrylic
acid and/or methacrylic acid, and derivatives thereof, including alkylesters thereof
such as n-butylacrylate or methylmethacrylate or cyano derivates thereof such as cyanoacrylate.
The step of applying the adhesive is performed by an adhering station (13) consisting
of an adhesive chamber, which applies adhesive on a steel or ceramic transferation
roll (20) having a rough surface. This adhesive transferation roll (20) is in contact
with an adhesive application roll (21), having a rubber surface. Adhesive will be
applied to the tops of the raised portions (protuberances) while passing the adhering
unit. A lamination between the top and the bottom ply/plies will be obtained when
the webs are brought together and compressed in a marrying nip. Marrying the plies
is performed by pressing a rubber-coated roll (12) with a rubber hardness for approximately
80 Shore (A) on the decoration embossing roll (10) (with approximately 5.600 N/m).
Preferred adhesives are glues based on CMC, PVOH, EVA, PVAc, which are commonly used
for tissue products. The adhesive may additionally be dyed. However, due to smooth
edges of the decoration embossing the dye will drain away and smear. After lamination,
the multi-ply web is transferred to the rewinding unit. By means of such an apparatus
according to the prior art, a multi-ply paper product having a background embossing
and a decoration embossing can be obtained.
[0016] However, as the decoration embossing is applied to the paper product already being
micro-embossed or background-embossed, the background embossing is impaired in the
step of decoration embossing by compression and, thus, results in a loss of thickness.
In other words, the designs of the decoration embossing roll are pressed into the
rubber of the decoration backing roll so that the paper product will be compressed
in the clearances between the decoration elements, in which the rubber backing roll
engages, and, hence, the paper product will be reduced in its thickness.
[0017] In order to create more bulk, an alternative, conventional apparatus may be used
to apply a macro-embossing on a middle ply of the multi-ply paper product. However,
this apparatus is only applicable for paper products having at least three plies.
In Fig. 2, an apparatus for embossing a multi-ply paper product is shown in which,
compared to the apparatus in Fig. 1, a middle ply (14) of the paper product is embossed
in an additional middle embossing/backing roll combination (15) consisting of a rubber
backing roll (16) and an embossing roll (17) with a macro pattern (18). By this configuration,
products with a minimum of three plies can be manufactured which are increased in
bulk compared to products obtained by the aforementioned apparatus. However, this
approach is not applicable for two-ply products. In addition, the middle embossing/backing
combination (15) requires an additional drive to cope with the different web elongations
caused by the different embossing patterns. In addition, although more bulk than in
the standard apparatus as described with respect to Fig. 1 can be created by means
of the middle ply embossing, this bulk is again partly lost in the step of decoration
embossing, as the web undergoes the aforementioned compression.
[0018] In alternative (compared to the above) process for manufacturing multi-ply tissue
paper products having a decoration embossing and a micro embossing as background embossing,
the micro pattern and the decoration pattern are combined on one embossing roll and
the paper is concurrently embossed with both patterns. An apparatus having the features
defined in the preamble of claim 1 is known from
US-A-5,913,765.
3. Summary of the invention
[0019] Accordingly, it is the technical problem underlying the present invention to provide
an apparatus and a method for embossing a multi-ply paper product comprising at least
one background embossing unit for embossing at least one ply of the multi-ply paper
product and at least one decoration embossing unit for embossing the at least one
ply downstream of the background embossing unit, as seen in the direction of processing,
in which the loss of bulk of the paper product in the decoration embossing unit can
be reduced, which enables a larger flexibility in the election of the background pattern,
enables an increase in the edge sharpness of the edges of the decoration embossing,
which in turn leads to an improved application of dye in the sense of a sharp application,
if a dyed glue is used to laminate the plies, and enables production of a multi-ply
paper product having an improved optical appearance, thus solving the technical problems
of the prior art.
[0020] This technical problem is solved by an apparatus as defined in claim 1 and a method
as defined in claim 17. Preferred embodiments of the present invention may be taken
from the dependent claims.
[0021] In particular, the present invention provides an apparatus for embossing a multi-ply
paper product, comprising at least one background embossing unit, for embossing at
least one ply of the multi-ply paper product and at least one decoration embossing
unit for embossing the at least one ply downstream of the background embossing unit,
as seen in the direction of processing, wherein the decoration embossing unit having
a decoration embossing roll and a decoration backing roll. The apparatus of the present
invention is characterized in that the decoration embossing roll of the decoration
embossing unit has an engraving depth larger than 1,5 mm. Preferably, the engraving
depth is larger than 1,5 mm and less than or equal to 3,5 mm, more preferably in the
range of between 1,7 mm and 2,3 mm, and, most preferred, 2,0 mm. By employing a decoration
embossing roll having such an engraving depth, it can be ensured that, in step of
decoration embossing, the prebackground embossing is not or only slightly compressed
in the clearances between the decoration designs, such that the bulk of the paper
product achieved in the background embossing unit can be maintained. Consequently,
the decrease in bulk or thickness can be prevented. Further, the variety of embossing
patterns that can be used for the background patterns is increased because the optical
appearance and the mechanical properties thereby generated are not affected by the
subsequent decoration embossing unit. Additionally, the edge sharpness is increased,
thus improving the optical appearance of the paper product. In particular, if a dyed
adhesive is used for laminating the plies together, the decoration embossing, which
would be hardly distinguished from the background embossing in a white-in-white product,
can be highlighted. Because of the sharp edges, the dye does not drain away into the
background embossing, providing the decoration embossing with a sharp contour. In
other words, the decoration embossing can be accurately dyed.
[0022] To amplify this advantageous effect, in a preferred embodiment of the present invention,
the decoration backing roll has a hardness greater than 60 Shore (A), preferably greater
than 60 Shore (A) and less than or equal to 95 Shore (A), more preferably in the range
of between 75 and 85 Shore (A) and, most preferred, 80 Shore (A). By providing a backing
roll with such hardness, the designs of the decoration embossing roll are not pressed
into the decoration backing roll as deep as in conventional apparatuses. Consequently,
the paper product in the clearances between the designs is not compressed as much
as in the conventional apparatus, because the rubber backing roll in the present invention
engages the clearances much less than in the conventional apparatus. In addition to
the large engraving depth, this amplifies the afore-mentioned effect. But also if
taken alone, i.e. with a standard decoration embossing roll having an engraving depth
of between 1,2 mm and 1,5 mm, a decoration embossing roll having such hardness would
solve the object underlying the present invention.
[0023] Preferably, the decoration backing roll is made of natural or synthetic rubber, for
example, polybutadiene or copolymers of ethzylene and propylene, paper, cardboard
polyamide, textile or the like.
[0024] Advantageously, the background embossing unit is adapted to apply a macro-embossing
to the one ply of the paper product. ( A macro-embossing mainly serves to improve
the thickness of a paper product. Thus, by using a macro-embossing as background embossing,
the bulk of the paper product can be further increased. A macro-embossing has less
than 25 knobs, preferably between 5 and 16 knobs per cm
2.
[0025] However, the background embossing unit may be also adapted to apply a standard micro-embossing
to the one ply of the paper product. A micro-embossing is mainly used to improve handfeel
and drapability of the paper product and has in general more than 25 knobs up to 200
knobs pre cm
2.
[0026] Alternatively, the background embossing may also be a combination of a micro- and
a macro-embossing.
[0027] Preferably, the micro-embossing pattern is substantially uniformally applied to the
one ply of the paper product and comprises approximately 40 dots/cm
2. The micro-embossing may also be applied to some or all plies of the paper product.
[0028] Preferably, the apparatus is capable of producing a paper product having at least
three plies, wherein the background embossing unit further comprises a middle embossing/backing
roll combination for applying a macro-embossing to a middle-ply of the multi-ply paper
product. By this feature, the bulk of the paper product can be even further increased.
[0029] Preferably, the apparatus further comprises a calendar unit upstream and downstream
of the embossing units, as seen in the direction of processing, which increases the
softness or smoothness of the paper product and also increases its optical appearance.
[0030] Furthermore, the present invention provides a multi-ply paper product manufactured
by means of an apparatus as described above.
[0031] In addition, the present invention provides a corresponding method for embossing
a multi-ply paper product.
4. Brief description of the drawings
[0032] In the following, preferred embodiments of the present invention will be described
with reference to the accompanying drawings, in which same parts bear the same reference
numerals.
Fig. 1 is a side view of a state of the art apparatus for embossing a multi-ply paper
product.
Fig. 2 is a side view of an alternative apparatus according to the prior art, in which
the middle ply of a three-ply product is embossed with a macro pattern.
Fig. 3 shows a preferred embodiment of the present invention.
Fig. 4 shows a micro background pattern.
Fig. 5 shows a macro-embossing pattern.
Fig. 6 shows a decoration embossing pattern.
5. Detailed description of the drawings
[0033] Fig. 3 shows a preferred embodiment of the present invention. The principle arrangement
of the apparatus shown in Fig. 3 is similar to the conventional apparatus shown in
Fig. 1 and 2 described above. In order to avoid repetition, here the respective description
of same elements is omitted and reference is made to the description above of Fig.
1 and 2.
[0034] The shown embodiment differs from the one shown in Figs. 1 and 2 in that the decoration
embossing roll (10) has an engraving depth of, for example, 2 mm and the decoration
backing roll (11) has a hardness of 80 Shore (A). With these modifications, a loss
of bulk during the embossing of the design elements, i.e. during decoration embossing
can sufficiently be decreased, which also permits the use of a macro pattern (18)
for the background embossing (3).
[0035] However, it is sufficient to only provide one of the features of the decoration embossing
roll having an engraving depth of larger than 1,5 mm or a hardness of greater than
60 Shore (A) of the embossing backing roll to increase bulk. The additional middle
ply embossing and the usage of a macro background pattern further amplifies this effect,
but may be also omitted. The results of the respective features will become more apparent
from the following examples:
Example 1:
[0036] A three-ply tissue product in the form of a continuous web as a roll with a sheet
count of 150 has been manufactured having a micro-embossing as the background pattern,
as shown in Fig. 4, a macro pattern for the middle-embossed ply and a dolphin design,
as shown in Fig. 5, as the decoration embossing.
[0037] A first three-ply tissue product is produced on an apparatus according to Fig. 2
of the present application, namely with a state of the art apparatus, and a second
roll is produced by an apparatus according to the embodiment of the present invention,
wherein, compared to the standard apparatus, only the engraving depth of the decoration
embossing roll has been increased from 1,4 mm for the standard decoration embossing
roll to 2 mm for the decoration embossing roll of the present invention. The remaining
machine parameters, are constant (standard nips, web tension 30 N/m). Subsequently,
the two tissue products in the form of a roll are compared regarding their roll diameters.
[0038] The diameter of the standard roll (first roll) is 119 mm. In contrast, the diameter
of the roll (second roll) produced on an apparatus having a decoration embossing roll
with an engraving depth of 2 mm according to the present invention, is 128 mm. As
is apparent, the bulk of the tissue product obtained by an apparatus according to
the present invention has been significantly increased.
Example 2:
[0039] In the second example, a similar three-ply tissue product as in Example 1 has been
manufactured. However, in this example, for both products, the decoration embossing
roll has an engraving depth of 1,4 mm. In contrast to Example 1, the hardness of the
decoration backing roll of the standard apparatus on which a first standard roll is
produced is 50 Shore (A), whereas the hardness of the decoration backing roll of the
apparatus according to the embodiment of the present invention on which a second roll
is produced is 80 Shore (A). Again, all remaining machine parameters are constant.
[0040] The diameter of the three-ply tissue product roll (first roll) produced by the standard
apparatus is 119 mm, whereas the three-plied tissue product roll (second roll) produced
by the apparatus according to the present invention is 127 mm. Thus, the tissue product
roll is again significantly increased in its bulk in accordance with the present invention.
Example 3:
[0041] In the third example, also a similar three-ply tissue product has been produced,
but in this case the features mentioned in Examples 1 and 2 of the present invention
have been combined. Hence, one three-ply tissue product roll (first roll) is produced
by a standard apparatus, the decoration embossing roll having an engraving depth of
1,4 mm and a decoration backing roll having a hardness of 50 Shore (A). Further, a
second three-ply tissue product roll (second roll) is produced on an apparatus according
to a preferred embodiment of the present invention in which the engraving depth of
the decoration embossing roll is 2 mm and the hardness of the decoration backing roll
is 80 Shore (A). All remaining machine parameters are again constant. The diameter
measured for the standard three-ply tissue product roll (first roll) is again 119
mm, whereas the diameter of the three-ply tissue paper roll produced on an apparatus
according to the preferred embodiment of the present invention is 132 mm. As it will
be apparent, the bulk in this case is remarkably increased in accordance with the
present invention compared to the standard apparatus.
Example 4:
[0042] In the fourth example, a two-ply tissue product with a sheet count of 150 is produced
having a dolphin design, as shown in Fig. 5, as the decoration embossing pattern.
A first two-ply tissue paper roll is produced on an apparatus as shown in Fig. 1 of
the present application, having a decoration embossing roll with an engraving depth
of 1,4 mm, a decoration backing roll with a hardness of 50 Shore (A) and on which
a standard micro background pattern of 60 dots/cm
2 is applied in advance of the decoration embossing. In contrast, a second two-plied
tissue product roll is produced according to a preferred embodiment of the present
application, in which the decoration embossing roll has an engraving depth of 2 mm
and the decoration backing roll has a hardness of 80 Shore (A). Further, a macro pattern
is applied as background pattern, which is enabled due to the enlarged engraving depth
of the decoration embossing roll and the increased hardness of the decoration backing
roll.
Again, comparing the roll diameters, it becomes apparent that, in the standard apparatus,
a roll (first roll) is produced having a diameter of 123 mm, whereas in the apparatus
according to the preferred embodiment of the present invention, a roll (second roll)
diameter of 169 mm can be achieved. Also in this case, a remarkable increase in bulk
has been obtained in accordance with the present invention.
[0043] Fig. 4 shows an example of a standard micro pattern as background embossing. Various
forms of the knobs arepossible, such as ,e.g., a frustum (circular or oval) or a frustum
of pyramid (square or rectangular base).
[0044] Fig. 5, on the other hand, shows an example of a macro pattern, the knobs of which
may have the same form as the micro-embossing as aforementioned.
Fig. 6 shows an example of a design pattern in the form of dolphins as decoration
embossing.
[0045] As will be apparent, the present invention is not limited by the preferred embodiments
described with reference to the accompanying drawings, but can be modified in various
ways without departing from the scope of the invention defined in the appended claims.
1. Apparatus for embossing a multi-ply paper product, comprising at least one background
embossing unit (4, 5), for embossing at least one ply (7, 8) of the multi-ply paper
product and at least one decoration embossing unit for embossing the at least one
ply (7) downstream of the background embossing unit, as seen in the direction of processing,
the decoration embossing unit having a decoration embossing roll (10) and a decoration
backing roll (11),
characterized in that the decoration embossing roll of the decoration embossing unit has an engraving depth
larger than 1,5mm.
2. Apparatus according to claim 1, wherein the decoration embossing roll (10) has an
engraving depth larger than 1,5mm and less than or equal to 3,5mm.
3. Apparatus according to claims 1 or 2, wherein the engraving depth of the decoration
embossing roll (10) is 2,0mm.
4. Apparatus according to any one of the preceding claims, wherein the decoration backing
roll (11) has a hardness larger than 60 Shore (A).
5. Apparatus according to claim 4, wherein the hardness of the decoration backing roll
(11) is larger than 60 Shore (A) and less than or equal to 95 Shore (A).
6. Apparatus according to claim 4 or 5, wherein the hardness of the decoration backing
roll (11) is 80 Shore (A).
7. Apparatus according to any one of the preceding claims, wherein the decoration backing
roll (11) is made of rubber, paper, polyamide or textile.
8. Apparatus according to any one of the preceding claims, wherein the background embossing
unit (4, 5) is adapted to apply a macro embossing (18) to the one ply (7, 8) of the
paper product.
9. Apparatus according to claims 1 to 7, wherein the background embossing unit (4, 5)
is adapted to apply a micro embossing (6) to the one ply (7, 8) of the paper product.
10. Apparatus according to claims 1 to 7, wherein the background embossing unit (4, 5)
is adapted to apply a micro embossing (6) and a macro embossing (18) to the one ply
(7, 8) of the paper product.
11. Apparatus according to claim 9 or 10, wherein the micro embossing pattern to be substantially
uniformly applied to the one ply of the paper product comprises approximately 30 to
100 dots/cm2, preferably 40 dots/cm2.
12. Apparatus according to claim 8 or 10, wherein the macro embossing pattern to be substantially
uniformly applied to the one ply of the paper product comprises less than approximately
25 dots/cm2, and preferably between 5 to 16 dots/cm2.
13. Apparatus according to any one of the preceding claims, wherein the paper product
comprises at least three plies (7, 8, 14) and the background embossing unit (4, 5)
further comprises a middle embossing/backing roll combination (15) for applying a
macro embossing (18) to a middle ply of the multi-ply paper product.
14. Apparatus according to any one of the preceding claims, wherein the apparatus further
comprises a calander unit upstream or downstream of the embossing units, as seen in
the direction of processing.
15. Apparatus according to any one of.the preceding claims, comprising an adhering station
(13) for applying an adhesive, preferably a dyed adhesive, to the at least one ply.
16. Multi-ply paper product manufactured by means of an apparatus according to any one
of the preceding claims.
17. Method for embossing a multi-ply paper product, comprising the steps of embossing
at least one ply (7, 8) of the multi-ply paper product by means of a background embossing
unit, embossing the at least one ply (7) downstream of the step of the background
embossing by means of a decoration embossing unit, having a decoration embossing roll
(10) and a decoration backing roll (11), wherein the decoration embossing roll of
the decoration embossing unit has an engraving depth larger than 1,5mm, preferably
larger than 1,5mm and less than or equal to 3,5mm and most preferred 2,0mm.
18. Method according to claim 17, wherein the decoration backing roll (11) has a hardness
larger than 60 Shore (A), preferably larger than 60 Shore (A) and less than or equal
to 95 Shore (A) and most preferred 80 Shore (A).
19. Method according to claims 17 or 18, wherein in the step of the background embossing
a macro embossing (18) is applied to the one ply (7, 8) of the paper product.
20. Method according to claims 17 to 18, wherein in the step of the background embossing
a micro embossing (6) is applied to the one ply (7, 8) of the paper product.
21. Method according to claims 17 or 18, wherein in the step of the background embossing
a micro embossing (6) and a macro embossing (18) is applied to the one ply (7, 8)
of the paper product.
22. Method according to any one of claims 17 to 21, further comprising the step of applying
an adhesive, preferably a dyed adhesive to the at least one ply and marrying the at
least one ply with at least one other ply of the paper product.
1. Vorrichtung zum Prägen eines mehrlagigen Papierprodukts mit mindestens einer Hintergrundprägeeinheit
(4, 5) zum Prägen von mindestens einer Lage (7, 8) des mehrlagigen Papierprodukts
und mindestens einer Dekorprägeeinheit zum Prägen von mindestens einer Lage (7), und
zwar in Richtung der Verarbeitung hinter der Hintergrundprägeeinheit, wobei die Dekorprägeeinheit
eine Dekorprägerolle (10) und eine Dekorstützrolle (11) aufweist, dadurch gekennzeichnet, dass die Dekorprägerolle der Dekorprägeeinheit eine Gravurtiefe aufweist, die größer als
1,5 mm ist.
2. Vorrichtung nach Anspruch 1, bei der die Dekorprägerolle (10) eine Gravurtiefe aufweist,
die größer als 1,5 mm und kleiner als oder gleich 3,5 mm ist.
3. Vorrichtung nach Anspruch 1 oder 2, bei der die Gravurtiefe der Dekorprägerolle (10)
2,0 mm ist.
4. Vorrichtung nach einem der vorstehenden Ansprüche, bei der die Dekorstützrolle (11)
eine Härte aufweist, die größer als 60 Shore A ist.
5. Vorrichtung nach Anspruch 4, bei der die Härte der Dekorstützrolle (11) größer als
60 Shore A und kleiner als oder gleich 95 Shore A ist.
6. Vorrichtung nach Anspruch 4 oder 5, bei der die Härte der Dekorstützrolle (11) 80
Shore A ist.
7. Vorrichtung nach einem der vorstehenden Ansprüche, bei der die Dekorstützrolle (11)
aus Kautschuk, Papier, Polyamid oder Textil hergestellt ist.
8. Vorrichtung nach einem der vorstehenden Ansprüche, bei der die Hintergrundprägeeinheit
(4, 5) angepasst ist, eine Makroprägung (18) auf die eine Lage (7, 8) des Papierprodukts
aufzubringen.
9. Vorrichtung nach einem der Ansprüche 1 bis 7, bei der die Hintergrundprägeeinheit
(4, 5) angepasst ist, eine Mikroprägung (6) auf die eine Lage (7, 8) des Papierprodukts
aufzubringen.
10. Vorrichtung nach einem der Ansprüche 1 bis 7, bei der die Hintergrundprägeeinheit
(4, 5) angepasst ist, eine Mikroprägung (6) und eine Makroprägung (18) auf die eine
Lage (7, 8) des Papierprodukts aufzubringen.
11. Vorrichtung nach Anspruch 9 oder 10, bei der das im Wesentlichen einheitlich auf die
eine Lage des Papierprodukts aufzubringende Mikroprägemuster in etwa 30 bis 100 Punkte/cm2, bevorzugt 40 Punkte/cm2 aufweist.
12. Vorrichtung nach Anspruch 8 oder 10, bei der das im Wesentlichen einheitlich auf die
eine Lage des Papierprodukts aufzubringende Makroprägemuster weniger als in etwa 25
Punkte/cm2 und bevorzugt zwischen 5 bis 16 Punkte/cm2 aufweist.
13. Vorrichtung nach einem der vorstehenden Ansprüche, bei der das Papierprodukt mindestens
3 Lagen (7, 8, 14) aufweist und die Hintergrundprägeeinheit (4, 5) des Weiteren eine
mittlere Präge/Stützrollenkombination (15) zum Aufbringen einer Makroprägung (18)
auf eine mittlere Lage des mehrlagigen Papierprodukts aufweist.
14. Vorrichtung nach einem der vorstehenden Ansprüche, die des Weiteren eine Kalandereinheit
aufweist, und zwar in Richtung der Verarbeitung gesehen vor oder nach den Prägeeinheiten.
15. Vorrichtung nach einem der vorstehenden Ansprüche, mit einer Haftstation (13) zum
Aufbringen eines Haftmittels, bevorzugt eines gefärbten Haftmittels, auf die mindestens
eine Lage.
16. Mehrlagiges Papierprodukt, das mittels einer Vorrichtung nach einem der vorstehenden
Ansprüche hergestellt wird.
17. Verfahren zum Prägen eines mehrlagigen Papierprodukts, mit den Schritten:
Prägen mindestens einer Lage (7, 8) des mehrlagigen Papierprodukts mittels einer Hintergrundprägeeinheit,
Prägen der mindestens einen Lage (7) nach dem Schritt des Hintergrundprägens mittels
einer Dekorprägeeinheit, die eine Dekorprägerolle (10) und eine Dekorstützrolle (11)
aufweist, wobei die Dekorprägerolle der Dekorprägeeinheit eine Gravurtiefe aufweist,
die größer als 1,5 mm, bevorzugt größer als 1,5 mm und kleiner als oder gleich 3,5
mm und am bevorzugtesten 2,0 mm ist.
18. Verfahren nach Anspruch 17, bei dem die Dekorstützrolle (11) eine Härte aufweist,
die größer als 60 Shore A, bevorzugt größer als 60 Shore A und weniger als oder gleich
95 Shore A und am bevorzugtesten 80 Shore A ist.
19. Verfahren nach Anspruch 17 oder 18, bei dem während des Hintergrundprägeschritts eine
Makroprägung (18) auf die eine Lage (7, 8) des Papierprodukts aufgebracht wird.
20. Verfahren nach einem der Ansprüche 17 bis 18, bei dem während des Hintergrundprägeschritts
eine Mikroprägung (6) auf die eine Lage (7, 8) des Papierprodukts aufgebracht wird.
21. Verfahren nach Anspruch 17 oder 18, bei dem während des Hintergrundprägeschritts eine
Mikroprägung (6) und eine Makroprägung (18) auf die eine Lage (7, 8) des Papierprodukts
aufgebracht wird.
22. Verfahren nach einem der Ansprüche 17 bis 21, des Weiteren mit dem Schritt des Aufbringens
eines Haftmittels, bevorzugt eines gefärbten Haftmittels, auf die mindestens eine
Lage und Zusammenbringen der mindestens einen Lage mit mindestens einer anderen Lage
des Papierprodukts.
1. Dispositif de gaufrage d'un produit en papier multicouche, comprenant au moins une
unité de gaufrage d'arrière-plan (4, 5) pour gaufrer au moins une couche (7, 8) du
produit en papier multicouche et au moins une unité de gaufrage de décoration pour
gaufrer ladite au moins une couche (7) en aval de l'unité de gaufrage d'arrière-plan,
vue dans la direction du traitement, l'unité de gaufrage de décoration comportant
un rouleau de gaufrage de décoration (10) et un contre-rouleau de décoration (11),
caractérisé en ce que le rouleau de gaufrage de décoration de l'unité de gaufrage de décoration a une profondeur
de gravage supérieure à 1,5 mm.
2. Dispositif selon la revendication 1, dans lequel le rouleau de gaufrage de décoration
(10) a une profondeur de gravage supérieure à 1,5 mm et inférieure ou égale à 3,5
mm.
3. Dispositif selon la revendication 1 ou 2, dans lequel la profondeur de gravage du
rouleau de gaufrage de décoration (10) est de 2,0 mm.
4. Dispositif selon l'une quelconque des revendications précédentes, dans lequel le contre-rouleau
de décoration (11) a une dureté supérieure à 60 Shore (A).
5. Dispositif selon la revendication 4, dans lequel la dureté du contre-rouleau de décoration
(11) est supérieure à 60 Shore (A) et est inférieure ou égale à 95 Shore (A).
6. Dispositif selon la revendication 4 ou 5, dans lequel la dureté du contre-rouleau
de décoration (11) est de 80 Shore (A).
7. Dispositif selon l'une quelconque des revendications précédentes, dans lequel le contre-rouleau
de décoration (11) est en caoutchouc, papier, polyamide ou textile.
8. Dispositif selon l'une quelconque des revendications précédentes, dans lequel l'unité
de gaufrage d'arrière-plan (4, 5) est adaptée pour appliquer un macrogaufrage (18)
à ladite une couche (7, 8) du produit en papier.
9. Dispositif selon les revendications 1 à 7, dans lequel l'unité de gaufrage d'arrière-plan
(4, 5) est adaptée pour appliquer un microgaufrage (6) à ladite une couche (7, 8)
du produit en papier.
10. Dispositif selon les revendications 1 à 7, dans lequel l'unité de gaufrage d'arrière-plan
(4, 5) est adaptée pour appliquer un microgaufrage (6) et un macrogaufrage (18) à
ladite une couche (7, 8) du produit en papier.
11. Dispositif selon la revendication 9 ou 10, dans lequel le motif de microgaufrage devant
être appliqué substantiellement uniformément à ladite une couche du produit en papier
comprend approximativement de 30 à 100 points/cm2, de préférence 40 points/cm2.
12. Dispositif selon la revendication 8 ou 10, dans lequel le motif de macrogaufrage devant
être appliqué substantiellement uniformément à ladite une couche du produit en papier
comprend moins de approximativement 25 points/cm2, et de préférence entre 5 et 16 points/cm2.
13. Dispositif selon l'une quelconque des revendications précédentes, dans lequel le produit
en papier comprend au moins trois couches (7, 8, 14) et l'unité de gaufrage d'arrière-plan
(4, 5) comprend en outre une combinaison médiane de rouleaux de gaufrage et contre-rouleau
(15) pour appliquer un macrogaufrage (18) à une couche médiane du produit en papier
multicouche.
14. Dispositif selon l'une quelconque des revendications précédentes, dans lequel le dispositif
comprend en outre une unité de calandre en amont ou en aval des unités de gaufrage,
vue dans la direction de traitement.
15. Dispositif selon l'une quelconque des revendications précédentes, comprenant une station
d'encollage (13) pour appliquer un adhésif, de préférence un adhésif teinté, à ladite
au moins une couche.
16. Produit en papier multicouche fabriqué au moyen d'un dispositif selon l'une quelconque
des revendications précédentes.
17. Procédé de gaufrage d'un produit en papier multicouche, comprenant les étapes suivantes
:
gaufrer au moins une couche (7, 8) du produit en papier multicouche au moyen d'une
unité de gaufrage d'arrière-plan,
gaufrer ladite au moins une couche (7) en aval de l'étape de gaufrage d'arrière-plan
au moyen d'une unité de gaufrage de décoration, comportant un rouleau de gaufrage
de décoration (10) et un contre-rouleau de décoration (11), dans lequel le rouleau
de gaufrage de décoration de l'unité de gaufrage de décoration a une profondeur de
gravure supérieure à 1,5 mm, de préférence supérieure à 1,5 mm et inférieure ou égale
à 3,5 mm, et mieux encore égale à 2,0 mm.
18. Procédé selon la revendication 17, dans lequel le contre-rouleau de décoration (11)
a une dureté supérieure à 60 Shore (A), de préférence supérieure à 60 Shore (A) et
inférieure ou égale à 95 Shore (A), et mieux encore égale à 80 Shore (A).
19. Procédé selon la revendication 17 ou 18, dans lequel, dans l'étape du gaufrage d'arrière-plan,
un macrogaufrage (18) est appliqué à ladite une couche (7, 8) du produit en papier.
20. Procédé selon la revendication 17 ou 18, dans lequel, dans l'étape du gaufrage d'arrière-plan,
un microgaufrage (6) est appliqué à ladite une couche (7, 8) du produit en papier.
21. Procédé selon la revendication 17 ou 18, dans lequel, dans l'étape du gaufrage d'arrière-plan,
un microgaufrage (6) et un macrogaufrage (18) sont appliqués à ladite une couche (7,
8) du produit en papier.
22. Procédé selon l'une quelconque des revendications 17 à 21, comprenant en outre l'étape
consistant à appliquer un adhésif, de préférence un adhésif teinté, à ladite au moins
une couche et à assembler ladite au moins une couche avec au moins une autre couche
du produit en papier.