Technical field
[0001] The invention relates to improvements to embossed web materials, especially based
on tissue paper, of the multi-ply type, i.e. comprising at least two plies bonded
together, typically and preferably by gluing. The invention also relates to improvements
to the processing methods to emboss materials made of tissue paper or the like, to
obtain new and improved functional characteristics.
[0002] The invention also relates to a method for the production of a material of this type.
Prior art
[0003] Embossing is one of the operations that are normally performed on plies or sheets
of tissue paper, to produce paper articles for personal and household cleaning and
hygiene, and also for professional and industrial use, such as toilet paper, kitchen
towels, paper napkins and handkerchiefs and the like.
[0004] Embossing is an operation that is performed for the dual purpose of improving aesthetic
properties and increasing functional properties, in particular the softness, smoothness,
absorption capacity or thickness of the finished material.
[0005] Normally, a tissue paper material, such as kitchen towel or toilet paper, is produced
from two or more plies of paper embossed separately and subsequently bonded together
by applying a glue and laminating the plies between counter-rotating rollers defining
a lamination nip.
[0006] Embossing is, for example, performed by feeding each ply between an embossing roller,
provided with protuberances, and a pressure roller with an outer surface coated in
yielding material, such as rubber or the like. In some machines embossing is performed
between two rollers made of steel or another hard material, one equipped with protuberances
and the other with corresponding recesses. The protuberances of the embossing roller
produce corresponding protuberances or projections in the paper ply. The protuberances
formed in the two outermost plies are facing the inside of the finished product.
[0007] According to a possible technique (known as "tip-to-tip"), the two plies of paper
web material are bonded by making at least some of the protuberances of one ply coincide
with the protuberances of the other ply, having previously applied glue to the protuberances
of one of the two plies, or to at least some of these protuberances. In practice,
in tip-to-tip embossing machines two embossing rollers which emboss the two paper
plies separately by means of respective pressure rollers, form therebetween a lamination
nip, through which the two embossed plies are fed before being detached from the rollers.
In the lamination nip the protuberances of one roller coincide with the protuberances
of the other roller and the reciprocal distance between the rollers is such as to
cause localized compression of the plies at said protuberances.
[0008] A tip-to-tip embossing unit to obtain a product of this type is described in
US-A-3,414,459. Further tip-to-tip embossing units are described in
US-A-5,173,351;
US-A-6,032,712;
US-A-6,245,414;
US-A-6,053,232.
[0009] US-A-3,961,119 discloses a method for the production of a two-ply embossed web or sheet material,
wherein two plies are individually embossed between an embossing roller and a pressure
roller. The embossing rollers are provided with helically developing projections and
grooves. The first roller has projections with individual protrusions thereon, matching
with indentations provided on the helical projections of the second embossing roller.
Glue is applied on the first ply in correspondence of said individual protrusions,
such that the two plies are spot-glued to one another in correspondence of said protrusions
and indentations.
[0010] According to a different technique, known as "nested", the two plies are embossed
separately, each between an embossing roller and a counter-roller or pressure roller,
and then matched so that the protuberances of one ply are inserted between the protuberances
of the other ply. Lamination of the two plies to obtain reciprocal bonding is performed
between one of the embossing rollers an a laminating roller, while the two embossing
rollers do not normally touch. Examples of embossing-laminating devices of this type
are described in
US-A-3,556,907;
US-A-3,867,225;
US-A-5,339,730.
[0011] US-A-5,686,168 describes a method of nested embossing, wherein the plies are bonded by lamination
between two opposed embossing rollers.
[0012] US-A-6,578,617 and
US-A-6,470,945 describe embossing units that can perform embossing according to both techniques,
i.e. nested or tip-to-tip. To switch from tip-to-tip to nested embossing, the reciprocal
angular position and/or the reciprocal axial position of the two embossing rollers
can be modified.
[0013] US-A-6,261,666 describes an analogous device for alternatively performing tip-to-tip or nested embossing.
Another similar device is described in
US-A-6,109,326.
[0014] Initially, embossing was performed according to very simple geometric patterns, with
uniform distribution of truncated-cone or truncated-pyramid shaped protuberances.
These embossings had a prevalently technical function, and were used to produce a
product of adequate thickness and with sufficient softness and absorption capacity.
[0015] Currently, embossing must increasingly achieve a dual function, both technical-functional
and aesthetic. Therefore, embossing patterns and embossing devices have been developed
which make it possible to obtain a product that is aesthetically pleasing and at the
same time suitable to satisfy the aesthetic requirements and increasing commercial
requirements demanded of these products. Examples of complex embossing patterns with
a technical and aesthetic function are described in
US-A-6,136,413;
US-A-5,846,636;
US-A-6,106,928.
[0016] A new embossing technique that makes it possible to obtain particularly refined and
easily interchangeable motifs is described in
US-A-6,755,928 and in
US-A-6,681,826.
[0017] The technical function of embossing tissue paper products has always been aimed at
increasing the liquid absorption properties and apparent thickness of the product.
In fact, embossing was, and continues to be, utilized prevalently in the field of
kitchen towels, more than in the field of toilet paper.
Objects and summary of the invention
[0018] An object of the invention is to produce an embossing pattern that gives the tissue
paper a different function from that of conventional products.
[0019] This object is achieved with a method according to claim 1 and with a product according
to claim 4. Additional advantageous embodiments and features of the method and product
according to the invention are set forth in the dependent claims.
[0020] In substance, according to a first aspect, the invention relates to a method to increase
the cleaning capacity of a sheet of multi-ply tissue paper comprising a first surface
and a second surface, wherein at least one of said first and second surfaces is embossed
to obtain surface portions defining outwardly projecting protuberances projecting
of the sheet, delimited at least partly by substantially linear grooves extending
inside the sheet, said grooves defining spaces to collect a material removed by passing
said sheet over a surface to be cleaned, and said outwardly projecting protuberances
defining areas of surface contact with said surface to be cleaned.
[0021] Preferably, a glue is applied to some or all of the lines defining the bottom of
the substantially linear grooves. In this way the areas of embossed ply forming the
outwardly projecting protuberances are more resistant to compression, as the portion
of outwardly projecting ply material of the web material is at least partly surrounded
by lines of glue, which bond the material of the ply to the ply below, preventing
the intermediate ply material from collapsing. This increased resistance to compression
is useful both to preserve the form of the product wound in a roll, and to maintain
the three-dimensional nature of the embossing pattern during use, e.g. when the product
is passed over the surface to be cleaned exerting a certain amount of pressure.
[0022] According to a different aspect, the invention relates to a tissue paper sheet material
with a first surface and a second surface, comprising at least two plies of tissue
paper bonded together by gluing, wherein a three-dimensional cleaning surface pattern
is produced on at least said first surface of said sheet material, to clean surfaces
over which said sheet material is passed with said three-dimensional surface pattern
in contact with the surface to be cleaned, and wherein said three-dimensional surface
pattern comprises surface portions defining outwardly projecting protuberances of
said sheet material, at least partly delimited by grooves with substantially linear
extension, extending towards the inside of said sheet material, said grooves defining
spaces to collect the material removed by passing said sheet over said surface to
be cleaned and said outwardly projecting protuberances defining areas of surface contact
with said surface to be cleaned.
[0023] According to a further aspect, the invention provides a tissue paper multi-ply sheet
material and a method for the manufacturing thereof, said sheet material including
at least a first outer ply and a second outer ply of tissue paper bonded by gluing,
said first outer ply having a first, outwardly facing surface and a second, inwardly
facing surface; wherein at least said first outer ply has a three-dimensional surface
pattern comprising outwardly projecting, bulging embossed protuberances defined by
portions of said first outer ply, at least partly surrounded by substantially linear
grooves, extending towards the inside of said sheet material, and wherein said first
outer ply is provided with glue applied on the second, inwardly facing surface of
said first outer ply in correspondence of said linear grooves.
[0024] Further advantageous features and embodiments of the method and of the material according
to the invention are set forth in the dependent claims, which are incorporated in
the present description, and will be described in more detail hereunder with reference
to some non-limiting embodiments of the invention.
Brief description of the drawings
[0025] The invention will be better understood by following the description and accompanying
drawing, which shows some non-limiting practical embodiments of the invention. More
specifically, in the drawing:
Figure 1 shows a diagram of a first embossing-laminating unit not falling within the
scope of the claims;
Figure 2 shows a diagram of a second embossing-laminating unit not falling within
the scope of the claims n;
Figures 2A, 2B show enlarged details of Figure 2;
Figures 3 to 5 show sections and partial axonometric views of a portion of a web material
not falling within the scope of the claims;
Figures 6 and 7 show schematic plan views of possible embodiments of the embossing
pattern not falling within the scope of the claims;
Figure 8 shows a schematic section of a web material according to a further embodiment
not falling within the scope of the claims;
Figure 9 shows a plan view of a fragment of a further embodiment not falling within
the scope of the claims;
Figure 10 shows a schematic local section according to X-X in Figure 9;
Figures 11 to 13 show schematic plan views of further embossing patterns;
Figure 14 shows a schematic side view of an embossing device according to one embodiment
of the invention;
Figure 15 shows an enlargement of the detail shown at XV in Fig.14;
Figures 16-18 show enlarged and diagrammatic cross sections of multi-ply products
according to the invention;
Figure 16A shows a top plan view of a multi-ply product according to the invention;
Figure 19 shows a top plan view of an intermediate ply of a multi-ply paper material
in one embodiment of the invention;
Figure 20 shows a diagrammatic cross section of a multi-ply paper sheet including
two intermediate sheets shaped as shown in Figure 19;
Figure 21 shows a diagrammatic side view of a modified embodiment of an embossing
unit for the manufacturing of an embossed material according to the invention;
Figure 22 shows an enlargement of the detail shown at XXII in Figure 21; and
Figure 23 shows a further embodiment of an embossing arrangement for the production
of an article according to the invention.
Detailed description of embodiments of the invention
[0026] Figure 1 shows a diagram of an embossing unit, also known as embossing-laminating
unit, indicated as a whole with 2. The unit comprises a first embossing roller 1 and
a second embossing roller 3, rotating about respective rotation axes 1A and 3A. The
directions of rotation are indicated with f1 and f3. A nip G is defined between the
two embossing rollers, through which two plies of tissue paper V1 and V3 are fed,
which are separately embossed by the rollers 1 and 3, respectively. Embossing takes
place by feeding each of the plies between the respective embossing roller 1 or 3
and a corresponding pressure roller 5 or 7, the axes of rotation of which are indicated
with 5A and 7A. The rollers 5 and 7 are coated with a layer of yielding material,
such as rubber or the like, in which protuberances, indicated schematically and as
a whole with 1P and 3P in Figure 1, with which the embossing rollers 1 and 3 are equipped
penetrate. Possible configurations of these protuberances will be described in detail
hereunder.
[0027] According to a possible embodiment, in a way known per se, the two rollers 1 and
3 can be phased to position the protuberances 1 P and 3P in the tip-to-tip or nested
configuration. In the first condition, in the lamination nip G at least some of the
protuberances of the roller 1 coincide with the protuberances of the roller 3 and
the distance between the rollers 1 and 3 is such that sufficient pressure is exerted
between the protuberances to cause lamination and bonding of the plies V1 and V3.
In the second condition, the protuberances 1 P are intercalated between the protuberances
3P. In this case, reciprocal adhesion between the two plies V1 and V3 is obtained
by lamination between the embossing roller 1 and a laminating roller 13. The two alternative
paths of the web material N formed by the two plies V1 and V3 are indicated with Nn
and Npp, said paths differing according to whether the material is processed with
the tip-to-tip technique (path Npp) of with the nested technique (path Nn). It would
also be possible for the embossing-laminating unit 2 to be suitable only to produce
using the tip-to-tip technique or using the nested technique. In the first case, the
laminating roller 13 can be omitted, while in both cases, the characteristic of being
able to variably phase the rollers 1, 3 can be omitted. When, on the other hand, the
unit is two-purpose and can operate both in tip-to-tip and nested mode, the rollers
are reciprocally positionable with angular and/or axial phasing. The mechanical members
and in particular the supports for the rollers 1 and 3 which allow adjustment are
known per se and will not be described in greater detail herein.
[0028] A glue dispensing unit is indicated schematically with 17, and applies a glue to
the radially projecting surfaces of the ply V1 embossed by the roller 1, when this
ply is still engaged with the surface of said roller 1.
[0029] Figure 2 schematically shows the conformation of a different possible embossing machine
or unit, of the type described, for example, in
WO-A-99/44414. The two plies of tissue paper, again indicated with V1 and V3, are fed towards an
embossing unit or embossing-laminating unit 100 comprising an embossing roller 101
equipped with protuberances 101 P and cooperating with a lamination or marrying roller
103, which can optionally be coated with a material which is softer, or more yielding
than the material forming the surface of the embossing roller 105. A glue dispenser
107 cooperates with the embossing roller 105 to apply glue to the protuberances produced
through embossing by the projections 101 P in the ply V1 through pressure between
the embossing roller 101 and a pressure roller 109 coated in rubber or another yielding
material.
[0030] According to a possible embodiment, before being guided about the pressure roller
109, the ply V1 is fed into a secondary embossing unit 111 with an embossing roller
113 cooperating with a pressure roller 115. The surface of the embossing roller 113
is equipped with micro-embossing protuberances 113P.
[0031] According to an advantageous embodiment, the ply V3 is fed through a second secondary
embossing unit 114, comprising an embossing roller 117, the surface of which is equipped
with projections or protuberances 117P, cooperating with a pressure roller 119 similar
to the pressure roller 115.
[0032] The secondary embossing unit 111 can be omitted, as can the secondary embossing unit
114, depending on the type of pattern and machining to be performed on the paper material
formed by the two plies V1, V3.
[0033] The glue applied by the dispensing unit 107 to the projections of the paper deformed
between the pressure roller 109 and the embossing roller 101 is used to reciprocally
bond the two plies, which for this purpose are laminated in the nip formed by the
embossing roller 101 and the mating roller 103 to form multi-ply web material N delivered
from the embossing unit 100.
[0034] Figures 3 to 8 schematically show, in various views and sections, portions of a multi-ply
web material produced with one or other of the embossing units in Figures 1 and 2,
or other equivalent embossing units, utilizing the concepts underlying the invention.
[0035] Figure 3 represents a local section and partial perspective view of a portion of
a multi-ply web material constituted by two plies V1 and V3 embossed and laminated
in tip-to-tip configuration with a glue C to bond the two plies at the level of grooves
produced on said plies by the protuberances 1 P and 3P of the embossing rollers 1,
3 of the device in Figure 1 or other equivalent device.
[0036] As can be seen in Figure 3, the grooves, indicated with 201 for the ply V1 and with
203 for the ply V3, have a substantially linear extension and defined therebetween
are bulging portions 205, 207 of the web material formed by the outwardly projecting
plies V1, V3 of the web material defining projections with an elongated extension
delimited by adjacent grooves 201, 203. Figure 6 schematically shows in a top view
a portion of the web material N, i.e. observed from the side of the ply V1, embossed
as described above. In this example, the projections 205 and the grooves 201 have
a slightly undulating linear shape and the width of the portions 205 is much greater
than the width of the grooves 201.
[0037] By passing a web material with this conformation over a surface to be cleaned, e.g.
when the web material N forms a sheet of kitchen towel, a very efficient cleaning
effect is obtained on the surface, due to the fact that the portions 205 of material
project outward to form contact and cleaning surfaces, while the grooves 201 define
areas to collect the substances or products located on the surface to be cleaned and
which must be removed. The rounded convex conformation of the outwardly projecting
portions 205 of the ply V1 and of the outwardly projecting portions 203 of the ply
V3 make the product soft and pleasing to the touch. In this embodiment, the cleaning
effect is provided to the same degree on both faces of the web material.
[0038] According to an advantageous embodiment of the invention, on both faces the portions
205, 207 project from the base plane of the original ply, i.e. from the surface on
which the first ply lies before deformation by embossing. In fact, in relation to
this plane the grooves 201, 203 project towards the inside of the web article and
the protuberances 205, 207 project outward to form bulges or embossings with positive
effect. Embossing with positive effect is intended as an effect of deformation through
embossing wherein the cellulose ply has been deformed to project from the surface
of the original ply in relation to the shape thereof prior to embossing.
[0039] To ensure that the outwardly facing convex portions 205, 207 are not compressed,
above all when the web product is wound in rolls, according to an advantageous embodiment
each ply V1, V3 is in actual fact composed of a plurality of cellulose layers, to
provide adequate consistency and mechanical resistance to the finished product.
[0040] According to a different embodiment, resistance to compression can be obtained by
producing the web material N with an embossing technique of the nested type, as indicated
schematically in Figure 4. In this case, the web material N is again formed by the
plies V1 and V3, where the ply V1 is embossed to obtain grooves, again indicated with
201, having a linear extension, defined between which are areas 205 with outwardly
projecting convex profiles, i.e. areas of positive embossing.
[0041] Conversely, the ply V3 is embossed to form thereon projections 209 facing the inside
of the web material N and inserted in the empty space defined by the portions 205
of the ply V1. The protuberances 209 therefore form supports for the convex areas
205 of the ply V1 preventing or in any case reducing compression thereof. In the example
shown in Figure 4, the protuberances 209 facing the inside of the web material are
approximately in the shape of truncated cones, but it must be understood that they
can also have a conformation with linear extension like the grooves 201 produced on
the ply V1. The two plies V1 and V3 are bonded by a glue 5 applied to the surface
of the ply V1 facing the ply V3 at the level of the grooves 201.
[0042] The conformation of the surface of the ply V1 can substantially be identical to the
one illustrated in Figure 6, with grooves 201 with an undulated linear extension and
corresponding convex projections 205 with a width preferably greater than the width
of the grooves 201. The article N configured as shown in Figure 4 will have a preferred
active surface defined by the ply V1, with a cleaning capacity, i.e. capacity to remove
dirt from the surfaces to be cleaned, substantially equivalent to that of the web
material N in Figure 3. Conversely, the lower surface of the material, defined by
the ply V3, has a lesser cleaning capacity, substantially equivalent to as that of
conventional products.
[0043] Figure 5 shows a local section and partial perspective view of a web material N obtained,
for example, with an embossing-laminating device of the type illustrated in Figures
2, 2A and 2B. In this case, the ply V1 is still embossed as described with reference
to Figures 3 and 4, with the formation of convex projections 205 with a substantially
linear extension delimited by grooves 201. The glue C with which the ply V1 is bonded
to the ply V3 below is applied at the level of the grooves 201. The ply V3 has micro-embossing
obtained with the embossing unit 114. In the example shown in Figure 5, the ply V1
has no micro-embossing, and therefore the secondary embossing unit 111 substantially
remained idle or is not present. It would also be possible for the ply V1 to have
micro-embossing over which the embossing forming the projections 205 and the grooves
201 is positioned.
[0044] The surface conformation of the ply V1 can be the same as that shown in Figure 6.
[0045] Figure 7 shows a top view of a different embossing pattern of the ply V1 and/or of
the ply V3. The same numbers indicate the same or equivalent parts to those shown
in Figure 6. The pattern is characterized by a more marked undulation of the protuberances
and of the grooves on the surface of the ply.
[0046] Figure 8 shows a local section of an embossed web material according to the invention
obtained, for example, with an embossing-laminating unit as shown in Figure 1. The
same numbers indicate the same or equivalent parts to those in Figure 4. In this case,
inside the empty space produced under the projections 205 are several adjacent protuberances
or projections 209 produced on the ply V3.
[0047] Figure 9 shows a top view of a fragment of an embossed web material according to
the invention, with a different surface structure. In this case grooves, again indicated
with 201, are produced on the surface of the ply V1, arranged to at least partly surround
raised areas, i.e. outwardly facing convex areas, indicated with 205. These areas
205 form projections embossed according to a positive embossing as defined above.
[0048] Figure 9 shows a fragment of the web material with one of these projecting portions
205, surrounded by grooves 201 divided into four contiguous portions. It must be understood
that on the surface of the web material there can be a plurality of grooves 201 defining
the same number of projections 205 arranged according to a suitable pattern. The grooves
can have a different conformation, e.g. they can fully surround the projecting portions
205, and/or they can have a different geometrical shape in relation to the one shown.
[0049] Figure 10 shows a local section of a portion of the web material shown in Figure
9, in which it can be seen that arranged under the convex projection 205 are protuberances,
still indicated with 209, produced in the ply V3 and arranged in nested configuration
in the empty space inside the web material below the convex projections 205. It must
be understood that also in this case the lower ply V3 can be embossed with micro-embossing
as shown in Figure 5, or with a similar pattern to that of the ply V1 in a tip-to-tip
embossed configuration as shown in Figure 3 or in any other suitable way.
[0050] Therefore, in the embossing pattern in Figure 9 the projections 205 are constituted
by areas almost closed and surrounded by grooves 201, which no longer extend for a
substantially indefinite length like those in Figures 6 and 7. In any case, the convex
projecting portions 205 again define contact and cleaning surfaces, while the grooves
201 define spaces to collect the dirt and debris removed from the surface cleaned
with the web material N.
[0051] Figures 11 and 13 schematically show further possible embossing patterns according
to the invention. The lines represented in the drawings indicate embossing motifs
or patterns with linear extension, according to closed lines. In particular, Figure
11 shows embossing patterns characterized by embossed lines with double lobes, delimiting
an inner surface forming an outwardly facing convex projection of the web material.
Figure 12 shows an embossing pattern characterized by groups of closed, V-shaped embossing
lines with a wide aperture, arranged to produce a sort of flower. Figure 13 shows
closed embossing lines similar to the lines in Figure 12, but arranged according to
parallel and intercalated alignments.
[0052] In any case, the ply embossed with the embossing lines defining the outwardly projecting
areas of the web material can also have conventional embossing, intercalated with
these embossing lines forming the grooves, to "embed" the areas embossed with positive
embossing in areas embossed according to a conventional embossing motif.
[0053] Figure 14 shows a diagrammatic side view of an embodiment of an embossing unit for
manufacturing a multi-ply embossed paper sheet according to the invention in a particularly
preferred embodiment. The unit, designated 301 as a whole, includes a first embossing
roller 303 and a second embossing roller 305, defining a lamination nip 307 therebetween.
An enlargement of the lamination nip 307 is shown in Fig.15. Each embossing roller
303, 305 co-acts with a corresponding pressure roller 309, 311. The pressure rollers
309, 311 are provided with an outer pliable cover, made of elastically yielding material,
such as rubber or the like, shown at 309A and 311A respectively. Each embossing roller
forms, along with the corresponding pressure roller, an embossing nip, through which
a respective first and second outer ply V1 and V3 are fed. A glue applicator 313 applies
glue on the top surface of the embossing protrusions generated on ply V1 by the coaction
of rollers 303 and 309. A similar glue applicator can be arranged around the embossed
roller 305.
[0054] A first and a second intermediate plies V5, V7 are fed into the lamination nip 307
between embossing rollers 303, 305. Each ply V5, V7 is embossed in a respective auxiliary
embossing device 315, 317. Each auxiliary embossing device includes an embossing roller
315A, 317A provided with outwardly oriented protrusions (see enlargement of roller
315A), co-acting with a pressure roller 317A, 317B provided with an elastic yielding
surface.
[0055] As shown more specifically in Fig. 15, the two embossing rollers 303, 305 are provided
with protrusions 303P and 305P. In a preferred embodiment, the protrusions 303P, 305P
are arranged in a tip-to-tip or foot-to-foot arrangement as shown in detail in Fig.15.
This means that the protrusions of one roller are substantially in phase with those
of the opposing roller. The four plies V1, V3, V5, V7 are laminated together at the
mutually corresponding top surfaces of the opposing protrusions 303P, 305P, so that
they are glued together by means of the adhesive applied by the glue distributor 313
and possibly by the second glue distributor 313A (if present).
[0056] Fig 16 shows an enlarged diagrammatic cross section of a product which can be obtained
with the unit of Figs. 14, 15. The outer plies V1, V3 are embossed such as to form
bubbles or bulging protrusions B and B1 extending towards the outside. Inwardly oriented
depressions or grooves D and D1 are generated in the two plies by the protrusions
303P, 305P of the rollers 303 and 305. The two inner plies V5, V7 are arranged within
the outer plies V1, V3 and their protrusions (generated by auxiliary embossing devices
315, 317 protrude towards the outer plies V1, V3, such as to form a supporting structure,
which limits the risk of the bulging protrusions B, B1 collapsing towards the interior
of the product. The height H of the bulging protrusions extending towards the outside
of the product can be larger than the height h of the inner protrusions formed in
the intermediate plies. For example the height H can range from 1.2 to 1.6 mm and
preferably around 1.4 mm, while the height h can range between 1.0 and 1.4 and preferably
between 1.1 and 1.3 mm. It shall be understood that these values are given by way
of example only and are not to be considered limitative of the invention.
[0057] Fig.16A shows a top plan view of a fragment of a product according to the invention.
Bulging protrusions are shown again at B, each protrusion being surrounded by a closed
inwardly oriented linear groove or depression D. The bottom portions of the grooves
or depressions D (or at least part thereof) are provided with glue. In the example
shown each protrusion B is entirely surrounded by a groove or depression D extending
along a closed line. This line can be however only substantially closed, i.e. it can
partly but not entirely surround the protrusion B. According to some embodiments of
the invention, a substantially closed line shall be understood as a line, which covers
at least 60% and preferably at least 70% and most preferably at least 80% of the linear
perimeter of the protrusion B.
[0058] The bulging protrusions B extend towards the outside forming a sort of bubble. The
bubble is at least partly prevented from collapsing by the linear glue distribution
along the partly or entirely closed groove or depression line D surrounding the protrusions
B, in combination with the protrusions of the intermediate plies V5, V7.
[0059] A similar embossing pattern and a similar effect can be achieved in other embodiments
of the product according to the invention as described above.
[0060] Fig.17 shows a modified embodiment of the product according to the invention. In
this case only one intermediate ply V5 is provided and the second outer ply V3 is
substantially smooth, i.e. not embossed. This product can be achieved by removing
or making the auxiliary embossing device 313 inactive and by replacing the roller
305 with one which is substantially smooth, i.e. not provided with protrusions. As
an alternative, the roller 305 can be moved away from roller 303, such that the two
rollers are not pressed one against the outer in the lamination nip 307 and a further
marrying or lamination roller with a smooth surface is arranged e.g. downstream of
the nip 307, said marrying or lamination roller being pressed against the protrusions
of roller 303.
[0061] Figs. 19, 20 show a further embossing pattern according to the invention. More specifically,
Fig.19 shows a top view of a fragment of one of the inner plies V5, V7. In this embodiment
the or each one of the inner plies has embossing lines surrounding bulging protrusions
BP in the shape of elongated projections. Fig. 20 shows the four-ply product resulting
from the embossing and lamination of plies V1, V3, V5, V7 with the embossing unit
301 of Fig. 14 using inner plies embossed according to the pattern in Fig.19. According
to some embodiments the inner plies V5, V7 are arranged randomly, as shown in Fig.20,
i.e. there is no pre-established correspondence between the protrusions of one ply
and those of the other ply.
[0062] Fig.18 shows still a further embodiment of the product according to the invention.
In this embodiment only one inner ply V5 is provides, said ply being provided with
protrusions which project from both surfaces towards both outer plies V1 and V3. The
product of Fig.18 can be obtained with an embossing and laminating unit shown in Figs,
21 and 22, and again designated 301 as a whole. The same reference numbers are used
to indicate elements and parts of the unit which are identical or equivalent to those
of Fig.14. The main difference between the two embodiments is that in Figs 21, 22
the auxiliary embossing unit 315 is comprised of two embossing rollers each provided
with protrusions (see Fig.22, showing an enlargement of the embossing nip between
rollers 315X, 315Y). The protrusions of the two rollers mesh with each other such
as to generate protrusions on both surfaces of the ply V5.
[0063] In all embodiments where inner plies are laminated along with outer plies as shown
e.g. in Figs. 16-20 the protrusions generated in the inner ply or plies are flattened
in correspondence of the depressions, i.e. the inwardly oriented grooves D of the
outer plies V1, V5.
[0064] According to a preferred embodiment of the invention, when the paper web has at two
inner plies and two outer plies, the inner plies are arranged in a tip-to-tip arrangement,
wherein at least part of the protrusions of the two plies are opposing each other
such as to increase the overall thickness of the product.
[0065] In a further embodiment, schematically shown in Fig.23, the two inner plies are embossed
in a tip-to-tip embossing and laminating unit 401 combined to the embossing and laminating
unit 301. The same reference numbers are used in Fig.23 to designate the same or equivalent
parts and elements as in Fig.21. The two inner plies V5, V7 are fed in respective
embossing nips formed by first and second embossing rollers 401, 403 and two pressure
rollers 405, 407. The two embossed plies V5, V7 are then fed through a lamination
nip between embossing rollers 401, 403 where they are bonded together. Glue can be
applied e.g. by means of a glue applicator 409 arranged around the periphery of embossing
roller 401 or alternatively around embossing roller 403. The unit 401 is quite the
same as unit 301, but the protrusions of the embossing rollers 401, 403 are smaller
in size and preferably of simpler shape. For example they can have the shape shown
in Fig.19. The protrusions of the embossing rollers 401, 403 can be distributed with
a density higher than 15 protrusions per square centimeter, and preferably between
20 and 300 protrusions per square centimeter, more preferably between 30 and 150 protursions
per square centimeter or any range within the values mentioned above.
[0066] It is understood that the drawing merely shows an example provided by way of a practical
arrangement of the invention, which can vary in forms and arrangement without however
departing from the scope of the concept underlying the invention.
1. Method for producing an embossed multi-ply tissue paper sheet, (N) comprising at least
a first outer ply (V1) and a second outer ply (V3), said first outer ply having a
first, outwardly facing surface and a second, inwardly facing surface, wherein at
least said first outer ply is embossed to obtain surface portions defining outwardly
projecting protuberances of the ply formed by bulging portions of sheet material,
at least partly surrounded by substantially linear grooves (201) projecting towards
the inside of the sheet, and wherein glue (C) is applied on the second, inwardly facing
surface of said first outer ply in correspondence of said linear grooves, to join
said first outer ply (V1) to said second outer ply (V3); and wherein between said
first outer ply (V1) and said second outer ply (V3) at least a first intermediate
embossed ply (V5) is arranged; embossing protrusions of said first intermediate embossed
ply being arranged in correspondence of the bulging embossed protuberances of at least
said first outer ply (V3).
2. Method according to claim 1, wherein said second outer ply (V3) is embossed to form
a three-dimensional surface pattern comprising outwardly projecting, bulging embossed
protuberances defined by portions of said second outer ply (V3), at least partly surrounded
by substantially linear grooves, extending towards the inside of said sheet material
(N); and wherein said second outer ply (V3) is provided with glue applied on an inwardly
facing surface of said second outer ply in correspondence of said linear grooves.
3. Method according to claim 1 or 2, wherein a second intermediate embossed ply (V7)
is arranged between said first outer ply (V1) and said second outer ply (V3).
4. A tissue paper multi-ply sheet material comprising at least a first outer ply (V1)
and a second outer ply (V3) of tissue paper bonded by gluing, said first outer ply
(V1) having a first, outwardly facing surface and a second, inwardly facing surface;
wherein at least said first outer ply (V1) has a three-dimensional surface pattern
comprising outwardly projecting, bulging embossed protuberances defined by portions
of said first outer ply (V1), at least partly surrounded by substantially linear grooves,
extending towards the inside of said sheet material; and wherein said first outer
ply (V1) is provided with glue (C) applied on the second, inwardly facing surface
of said first outer ply (V1) in correspondence of said linear grooves; and wherein
between said first outer ply (V1) and said second outer ply (V3) at least a first
intermediate embossed ply (V5) is arranged, embossing protrusions of said first intermediate
embossed ply (V5) being arranged in correspondence of the bulging embossed protuberances
of at least said first outer ply.
5. Multi-ply sheet material according to claim 4, wherein said outwardly projecting,
bulging embossed protuberances of said first outer ply (V1) are delimited by said
linear grooves forming substantially closed lines surrounding said bulging protuberances.
6. Multi-ply sheet material according to claim 4 or 5, wherein said second outer ply
(V3) has a three-dimensional surface pattern comprising outwardly projecting, bulging
embossed protuberances defined by portions of said second outer ply, at least partly
surrounded by substantially linear grooves, extending towards the inside of said sheet
material; and wherein said second outer ply is provided with glue applied on an inwardly
facing surface of said second outer ply in correspondence of said linear grooves.
7. Multi-ply sheet material according to claim 5, wherein said outwardly projecting,
bulging embossed protuberances on said second outer ply (V3) are delimited by said
linear grooves forming substantially closed lines surrounding said bulging embossed
protuberances.
8. Multi-ply sheet material according to claim 6 or 7, wherein between said first and
said second ply at least a first intermediate embossed ply is arranged, embossing
protrusions of said first intermediate embossed ply being arranged in correspondence
of the bulging embossed protuberances of said first outer ply and said second outer
ply.
9. Multi-ply sheet material according to claim 6 or 7 or 8, wherein the bulging embossed
protuberances of said first outer ply (V1) are arranged in a face-to-face arrangement
with the bulging embossed protuberances of said second outer ply (V3).
10. Multi-ply sheet material according to one or more of claims 6, 7 or 8 or 9, wherein
said inwardly facing linear grooves of said first outer ply (V1) and of said second
outer ply (V3) are phased in a tip-to-tip arrangement.
11. Multi-ply sheet material according to claim 8, 9 or 10, wherein: said first intermediate
embossed ply (V3) has a first surface facing said first outer ply (V1) and a second
surface facing said second outer ply (V3); and said first intermediate ply (V5) has
embossment protrusions projecting from both said first and second surface towards
said first outer ply (V1) and said second outer ply (V3), into cavities formed by
said bulging embossed protuberances of said first outer ply and of said second outer
ply.
12. Multi-ply sheet material according to claim 8, 9 or 10, including a second intermediate
embossed ply (V7) arranged between said first outer ply (V1) and said second outer
ply (V3).
13. Multi-ply sheet material according to claim 12, wherein said first and second intermediate
embossed plies (V5, V7) are provided each with embossing projections facing towards
the first outer ply (V1) and the second outer ply (V3) respectively.
14. Multi-ply sheet material according to claim 13, wherein said first and second intermediate
embossed plies (V5, V7) each have embossing projections formed by bulging embossed
protuberances facing towards said first and second outer ply (V1, V3) respectively,
said bulging embossed protuberances being surrounded by linear grooves facing away
from said first and second outer plies.
15. Multi-ply sheet material according to claim 12, 13 or 14, wherein said first and second
intermediate embossed plies (V5; V7) are arranged in a tip-to-tip arrangement.
16. Multi-ply sheet material according to one or more of claims 4 to 15, wherein said
first intermediate embossed ply (V4) is flattened in correspondence of said substantially
linear embossed grooves of said first outer ply (V1).
17. Multi-ply sheet material according to one or more of claims 4 to 16, wherein said
outwardly projecting, bulging embossed protuberances are each surrounded by glued
areas projecting inwardly inside said sheet material.
18. Multi-ply sheet material according to one or more of claims 4 to 17, wherein said
outwardly projecting, bulging embossed protuberances are bubble-shaped.
19. Multi-ply sheet material according to one or more of claims 4 to 18, wherein said
three-dimensional surface pattern is formed by deformation through embossing wherein
the embossed ply has been deformed to project outwardly from the surface of the original
ply.
1. Verfahren zur Herstellung eines geprägten mehrlagigen Tissuepapierblattes (N), umfassend
zumindest eine erste äußere Lage (V1) und eine zweite äußere Lage (V3), wobei die
erste äußere Lage eine erste, nach außen zeigende Oberfläche und eine zweite, nach
innen zeigende Oberfläche besitzt, wobei zumindest die erste äußere Lage geprägt wird,
um Oberflächenabschnitte zu erhalten, die durch gewölbte Abschnitte von Blattmaterial
geformte, nach außen stehende Vorsprünge der Lage bestimmen, die zumindest teilweise
von im Wesentlichen linearen, gegen die Innenseite des Blattes gerichteten Nuten (201)
umgeben sind, und wobei ein Kleber (C) auf der zweiten, nach innen zeigenden Oberfläche
der ersten äußeren Lage entsprechend den linearen Nuten aufgebracht wird, um die erste
äußere Lage (V1) mit der zweiten äußeren Lage (V3) zu verbinden, und wobei zwischen
der ersten äußeren Lage (V1) und der zweiten äußeren Lage (V3) zumindest eine erste
geprägte Zwischenlage angeordnet wird, wobei geprägte Ausbuchtungen der ersten geprägten
Zwischenlage in Übereinstimmung mit den gewölbten geprägten Vorsprüngen der wenigstens
ersten äußeren Lage (V3) angeordnet werden.
2. Verfahren nach Anspruch 1, wobei die zweite äußere Lage (V3) geprägt wird, um ein
dreidimensionales Oberflächenmuster zu bilden, das nach außen stehende, gewölbt geprägte
Vorsprünge umfasst, die durch Abschnitte der zweiten äußeren Lage (V3) bestimmt werden
und zumindest teilweise durch im Wesentlichen lineare, sich gegen die Innenseite des
Blattmaterials (N) erstreckende Nuten umgeben sind, und wobei die zweite äußere Lage
(V3) mit einem Kleber versehen wird, der auf einer nach innen zeigenden Oberfläche
der zweiten äußeren Lage in Übereinstimmung mit den linearen Nuten aufgebracht wird.
3. Verfahren nach Anspruch 1 oder 2, wobei eine zweite geprägte Zwischenlage (V7) zwischen
der ersten äußeren Lage (V1) und der zweiten äußeren Lage (V3) angeordnet wird.
4. Mehrlagiges Tissuepapier-Blattmaterial, umfassend zumindest eine erste äußere Lage
(V1) und eine zweite durch Kleben verbundene äußere Lage (V3) eines Tissuepapiers,
welche erste Lage (V1) eine erste, nach außen zeigende Oberfläche und eine zweite,
nach innen zeigende Oberfläche besitzt, wobei zumindest die erste äußere Lage (V1)
ein dreidimensionales Oberflächenmuster aufweißt, umfassend nach außen stehende, gewölbt
geprägte Vorsprünge, die durch Abschnitte der ersten äußeren Lage (V1) bestimmt und
zumindest teilweise von im Wesentlichen linearen, sich gegen die Innenseite des Blattmaterials
erstreckenden Nuten umgeben sind, und wobei die erste äußere Lage (V1) mit einem Kleber
(C) versehen ist, der auf die zweite, nach innen zeigende Oberfläche der ersten äußeren
Lage in Übereinstimmung mit den linearen Nuten aufgebracht ist, und wobei zwischen
der ersten äußeren Lage (V1) und der zweiten äußeren Lage (V3) zumindest eine erste
geprägte Zwischenlage (V5) angeordnet ist, wobei geprägte Vorsprünge der ersten geprägten
Zwischenlage (V5) in Übereinstimmung mit den gewölbt geprägten Vorsprüngen der wenigstens
ersten äußeren Lage angeordnet sind.
5. Mehrlagiges Blattmaterial nach Anspruch 4, wobei nach außen stehende, gewölbt geprägte
Vorsprünge der ersten äußeren Lage (V1) durch lineare Nuten begrenzt werden, die im
Wesentlichen geschlossene, die gewölbten Vorsprünge umgebende Linien bilden.
6. Mehrlagiges Blattmaterial nach Anspruch 4 oder 5, wobei die zweite äußere Lage (V3)
ein dreidimensionales Oberflächenmuster aufweist, umfassend nach außen stehende, gewölbt
geprägte Vorsprünge, die durch Abschnitte der zweiten äußeren Lage bestimmt und zumindest
teilweise von im Wesentlichen linearen sich gegen die Innenseite des Blattmaterials
erstreckenden Nuten umgeben sind, und wobei die zweite äußere Lage mit einem Kleber
versehen ist, der auf eine nach innen zeigenden Oberfläche der zweiten äußeren Lage
in Übereinstimmung mit den linearen Nuten aufgebracht ist.
7. Mehrlagiges Blattmaterial nach Anspruch 5, wobei die nach außen stehenden, gewölbt
geprägten Vorsprünge auf der zweiten äußeren Lage (V3) durch lineare Nuten begrenzt
sind, die im Wesentlichen geschlossene, die gewölbten Vorsprünge umgebende Linien
bilden.
8. Mehrlagiges Blattmaterial nach Anspruch 6 oder 7, wobei zwischen der ersten und zweiten
Lage zumindest eine geprägte Zwischenlage angeordnet ist, wobei geprägte Vorsprünge
der ersten geprägten Zwischenlage in Übereinstimmung mit den gewölbt geprägten Vorsprüngen
der ersten äußeren Lage und der zweiten äußeren Lage angeordnet sind.
9. Mehrlagiges Blattmaterial nach Anspruch 6 oder 7 oder 8, wobei die gewölbt geprägten
Vorsprünge der ersten äußeren Lage (V1) gegenüberliegend zu den gewölbt geprägten
Vorsprüngen der zweiten äußeren Lage (V3) angeordnet sind.
10. Mehrlagiges Blattmaterial nach einem oder mehreren der Ansprüche 6, 7 oder 8 oder
9, wobei die nach innen zeigendes linearen Nuten der ersten äußeren Lage (V1) und
der zweiten äußeren Lage (V3) auf einander in einer tip-to-tip Anordnung ausgerichtet
sind.
11. Mehrlagiges Blattmaterial nach Anspruch 8, 9 oder 10, wobei die erste geprägte Zwischenlage
(V3) eine erste der ersten äußeren Lage (V1) gegenüber liegende Oberfläche und eine
zweite der zweiten äußeren Lage (V3) gegenüber liegende Oberfläche aufweist, und diese
erste Zwischenlage (V5) Prägevorsprünge besitzt, die sich sowohl von der ersten als
auch von der zweiten Oberfläche gegen die erste äußerer Lage (V1) und die zweite äußere
Lage (V3) in Hohlräume erstrecken, die von den gewölbt geprägten Vorsprüngen der ersten
äußeren Lage und der zweiten äußeren Lage gebildet sind.
12. Mehrlagiges Blattmaterial nach Anspruch 8,9 oder 10, beinhaltend eine zweite geprägte
Zwischenlage (V7), die zwischen der ersten äußeren Lage (V1) und der zweiten äußeren
Lage (V3) angeordnet ist.
13. Mehrlagiges Blattmaterial nach Anspruch 12, wobei die ersten und zweiten geprägten
Zwischenlagen (V5, V7) jeweils mit gegen die erste äußere Lage (V1) und die zweite
äußere Lage (V3) gerichteten, geprägten Vorsprüngen versehen sind.
14. Mehrlagiges Blattmaterial nach Anspruch 13, wobei die ersten und zweiten geprägten
Zwischenlagen (V5, V7) jeweils geprägte Vorsprünge aufweisen, die durch gegen jeweils
die erste und zweite äußere Lage (V1, V3) gerichtete, gewölbt geprägte Vorsprünge
gebildet sind, welche gewölbt geprägte Vorsprünge durch lineare Nuten umgeben sind,
die von den ersten und zweiten äußeren Lagen weggerichtet sind.
15. Mehrlagiges Blattmaterial nach Anspruch 12, 13 oder 14, wobei die ersten und zweiten
geprägten Zwischenlagen (V5, V7) in einer tip-to-tip Anordnung ausgerichtet sind.
16. Mehrlagiges Blattmaterial nach einem oder mehreren der Ansprüche 4 bis 15, wobei die
erste geprägte Zwischenlage (V4) in Übereinstimmung mit den im Wesentlichen linear
geprägten Nuten der ersten äußeren Lage (V1) abgeflacht ist.
17. Mehrlagiges Blattmaterial nach einem oder mehreren der Ansprüche 4 bis 16, wobei die
nach außen gerichteten gewölbt geprägten Vorsprünge je von Klebebereichen umgeben
sind, die innerhalb des Blattmaterials nach innen zeigen.
18. Mehrlagiges Blattmaterial nach einem oder mehreren der Ansprüche 4 bis 17, wobei die
nach außen gerichteten gewölbt geprägten Vorsprünge blasenförmig sind.
19. Mehrlagiges Blattmaterial nach einem oder mehreren der Ansprüche 4 bis 18, wobei das
dreidimensionale Oberflächenmuster durch eine Prägeverformung gebildet ist, wobei
die geprägte Lage verformt worden ist, um von der Oberfläche der ursprünglichen Lage
nach außen zu zeigen.
1. Procédé de fabrication d'une feuille gaufrée de papier sanitaire et domestique à couches
multiples (N) comprenant au moins une première couche extérieure (V1) et une seconde
couche extérieure (V3), ladite première couche extérieure possédant une première surface
tournée vers l'extérieur et une seconde surface tournée vers l'intérieur, dans lequel
au moins ladite première couche extérieure est gaufrée pour obtenir des parties de
surface définissant des protubérances faisant saillie vers l'extérieur de la couche
formées par des parties gonflées de matériau en feuille, au moins partiellement entourées
par des rainures sensiblement linéaires (201) faisant saillie vers l'intérieur de
la feuille, et dans lequel de la colle (C) est appliquée sur la seconde surface tournée
vers l'intérieur de ladite première couche extérieure en correspondance avec lesdites
rainures linéaires, pour joindre ladite première couche extérieure (V1) à ladite seconde
couche extérieure (V3) ; et dans lequel entre ladite première couche extérieure (V1)
et ladite seconde couche extérieure (V3) au moins une première couche gaufrée intermédiaire
(V5) est agencée, des protubérances de gaufrage de ladite première couche gaufrée
intermédiaire étant agencées en correspondance avec les protubérances gaufrées gonflées
d'au moins ladite première couche extérieure (V3).
2. Procédé selon la revendication 1, dans lequel ladite seconde couche extérieure (V3)
est gaufrée pour former une configuration de surface tridimensionnelle comprenant
des protubérances gaufrées gonflées faisant saillie vers l'extérieur définies par
des parties de ladite seconde couche extérieure (V3), au moins partiellement entourées
par des rainures sensiblement linéaires, s'étendant vers l'intérieur dudit matériau
en feuille (N) ; et dans lequel ladite seconde couche extérieure (V3) est pourvue
de colle appliquée sur une surface tournée vers l'intérieur de ladite seconde couche
extérieure en correspondance avec lesdites rainures linéaires.
3. Procédé selon la revendication 1 ou 2, dans lequel une seconde couche gaufrée intermédiaire
(V7) est agencée entre ladite première couche extérieure (V1) et ladite seconde couche
extérieure (V3).
4. Matériau en feuille à couches multiples de papier sanitaire et domestique comprenant
au moins une première couche extérieure (V1) et une seconde couche extérieure (V3)
de papier sanitaire et domestique collées par collage, ladite première couche extérieure
(V1) possédant une première surface tournée vers l'extérieur et une seconde surface
tournée vers l'intérieur ; dans lequel au moins ladite première couche extérieure
(V1) comporte une configuration de surface tridimensionnelle comprenant des protubérances
gaufrées gonflées faisant saillie vers l'extérieur définies par des parties de ladite
première couche extérieure (V1), au moins partiellement entourées par des rainures
sensiblement linéaires, s'étendant vers l'intérieur dudit matériau en feuille ; et
dans lequel ladite première couche extérieure (V1) est pourvue de colle (C) appliquée
sur la seconde surface tournée vers l'intérieur de ladite première couche extérieure
(V1) en correspondance avec lesdites rainures linéaires ; et dans lequel, entre ladite
première couche extérieure (V1) et ladite seconde couche extérieure (V3), au moins
une première couche gaufrée intermédiaire (V5) est agencée, des protubérances de gaufrage
de ladite première couche gaufrée intermédiaire (V5) étant agencées en correspondance
avec les protubérances gaufrées gonflées d'au moins ladite première couche extérieure.
5. Matériau en feuille à couches multiples selon la revendication 4, dans lequel lesdites
protubérances gaufrées gonflées faisant saillie vers l'extérieur de ladite première
couche extérieure (V1) sont délimitées par lesdites rainures linéaires formant des
lignes sensiblement fermées entourant lesdites protubérances gonflées.
6. Matériau en feuille à couches multiples selon la revendication 4 ou 5, dans lequel
ladite seconde couche extérieure (V3) comporte une configuration de surface tridimensionnelle
comprenant des protubérances gaufrées gonflées faisant saillie vers l'extérieur définies
par des parties de ladite seconde couche extérieure, au moins partiellement entourées
par des rainures sensiblement linéaires, s'étendant vers l'intérieur dudit matériau
en feuille ; et dans lequel ladite seconde couche extérieure est pourvue de colle
appliquée sur une surface tournée vers l'intérieur de ladite seconde couche extérieure
en correspondance avec lesdites rainures linéaires.
7. Matériau en feuille à couches multiples selon la revendication 5, dans lequel lesdites
protubérances gaufrées gonflées faisant saillie vers l'extérieur sur ladite seconde
couche extérieure (V3) sont délimitées par lesdites rainures linéaires formant des
lignes sensiblement fermées entourant lesdites protubérances gaufrées gonflées.
8. Matériau en feuille à couches multiples selon la revendication 6 ou 7, dans lequel,
entre lesdites première et seconde couches, au moins une première couche gaufrée intermédiaire
est agencée, des protubérances de gaufrage de ladite première couche gaufrée intermédiaire
étant agencées en correspondance avec les protubérances gaufrées gonflées de ladite
première couche extérieure et ladite seconde couche extérieure.
9. Matériau en feuille à couches multiples selon la revendication 6 ou 7 ou 8, dans lequel
les protubérances gaufrées gonflées de ladite première couche extérieure (V1) présentent
un agencement face à face avec les protubérances gaufrées gonflées de ladite seconde
couche extérieure (V3).
10. Matériau en feuille à couches multiples selon une ou plusieurs des revendications
6, 7 ou 8 ou 9, dans lequel lesdites rainures linéaires tournées vers l'intérieur
de ladite première couche extérieure (V1) et de ladite seconde couche extérieure (V3)
présentent un agencement pointe à pointe.
11. Matériau en feuille à couches multiples
selon la revendication 8, 9 ou 10, dans lequel ladite première couche gaufrée intermédiaire
(V3) comporte une première surface tournée vers ladite première couche extérieure
(V1) et une seconde surface tournée vers ladite seconde couche extérieure (V3) ; et
ladite première couche intermédiaire (V5) comporte des protubérances de gaufrage faisant
saillie à partir desdites première et seconde surfaces vers ladite première couche
extérieure (V1) et ladite seconde couche extérieure (V3), dans des cavités formées
par lesdites protubérances gaufrées gonflées de ladite première couche extérieure
et de ladite seconde couche extérieure.
12. Matériau en feuille à couches multiples selon la revendication 8, 9 ou 10, comprenant
une seconde couche gaufrée intermédiaire (V7) agencée entre ladite première couche
extérieure (V1) et ladite seconde couche extérieure (V3).
13. Matériau en feuille à couches multiples selon la revendication 12, dans lequel lesdites
première et seconde couches gaufrées intermédiaires (V5, V7) sont chacune pourvues
de saillies de gaufrage tournées vers la première couche extérieure (V1) et la seconde
couche extérieure (V3), respectivement.
14. Matériau en feuille à couches multiples selon la revendication 13, dans lequel lesdites
première et seconde couches gaufrées intermédiaires (V5, V7) comportent chacune des
saillies de gaufrage formées par des protubérances gaufrées gonflées tournées vers
lesdites première et seconde couches extérieures (V1, V3), respectivement, lesdites
protubérances gaufrées gonflées étant entourées par des rainures linéaires tournées
dans une direction opposée auxdites première et seconde couches extérieures.
15. Matériau en feuille à couches multiples selon la revendication 12, 13 ou 14, dans
lequel lesdites première et seconde couches gaufrées intermédiaires (V5 ; V7) présentent
un agencement pointe à pointe.
16. Matériau en feuille à couches multiples selon une ou plusieurs des revendications
4 à 15, dans lequel ladite première couche gaufrée intermédiaire (V4) est aplatie
en correspondance avec lesdites rainures gaufrées sensiblement linéaires de ladite
première couche extérieure (V1).
17. Matériau en feuille à couches multiples selon une ou plusieurs des revendications
4 à 16, dans lequel lesdites protubérances gaufrées gonflées faisant saillie vers
l'extérieur sont chacune entourées par des zones collées faisant saillie vers l'intérieur
à l'intérieur dudit matériau en feuille.
18. Matériau en feuille à couches multiples selon une ou plusieurs des revendications
4 à 17, dans lequel lesdites protubérances gaufrées gonflées faisant saillie vers
l'extérieur présentent une forme de bulle.
19. Matériau en feuille à couches multiples selon une ou plusieurs des revendications
4 à 18, dans lequel ladite configuration de surface tridimensionnelle est formée par
déformation par l'intermédiaire de gaufrage dans lequel la couche gaufrée a été déformée
pour faire saillie vers l'extérieur à partir de la surface de la couche d'origine.