[0001] This invention relates to a method for manufacturing coated panels, as well as to
coated panels.
[0002] More particularly, the invention relates to a method for manufacturing coated panels,
which are of the type comprising a substrate and a decorative top layer provided on
top thereof. This may relate, for example, to floor panels substantially consisting
of a substrate, for example, a MDF or HDF (Medium or High Density Fiberboard) panel
and a top layer provided thereon, such as a laminate top layer.
[0003] In particular, the invention relates to a method for manufacturing coated panels
with a printed decor with a transparent or translucent layer of synthetic material
extending there above. It is known that such decor, whether or not by the intermediary
of primer layers, can be printed directly on the substrate. However, the decor also
may be provided on a material sheet, such as a paper sheet, which is incorporated
in said top layer. The transparent or translucent synthetic material layer forms a
protective layer above the printed decor and may comprise, for example, wear-resistant
particles, such as aluminum oxide. It is not excluded that this protective layer also
comprises a material sheet, such as a paper sheet. Such laminate floor panel may be
manufactured, for example, according to a DPL (Direct Pressure Laminate) or HPL (High
Pressure Laminate) technique. In the case of a DPL technique, one or more material
sheets provided with resin are brought, together with the substrate, in a press device,
where, by means of a pressing element and under the influence of increased pressure
and temperature, they are connected to each other as well as to the substrate. In
the case of a HPL technique, the top layer is formed separately on the basis of two
or more material sheets provided with resin, before the thus obtained top layer is
provided on the substrate, for example, by gluing it on the substrate.
[0004] Further, it is known, for example, from
WO 01/96689, that at the surface or the decorative side of such coated panels, a relief of impressed
portions can be formed, by which, for example, the natural structure of the motif
represented in said decor can be imitated. In this way, for example, in the case that
the decor represents a wood motif, one may work with a relief imitating a wood structure.
Such wood structure possibly may correspond to the underlying decor, by which then
so-called impressions in register with the printed decor are obtained.
[0005] For realizing a relief at the decorative side, as known, structured press elements
are applied. For manufacturing such press elements, various techniques are known,
for example, from
WO 2006/0066776. However, the press elements obtained by means of such methods still leave much to
be desired.
[0006] The present invention aims at an alternative method for manufacturing coated panels,
which, according to various preferred embodiments of the invention, can offer advantages
in respect to the state of the art.
[0007] To this aim, the present invention relates to a method for manufacturing coated panels,
wherein these panels are of the type comprising at least a substrate, a decor and
a top layer on the basis of synthetic material, wherein the method comprises at least
the following steps:
- producing a press element, wherein this press element is provided with a relief at
its surface, said relief comprising higher-situated zones and lower-situated zones;
- forming the aforementioned coated panels, wherein said press element is applied for
forming impressed portions in the decorative panels by means of said relief, and more
particularly in the decorative side of boards, from which then such coated panels
can be obtained;
with the characteristic that, when producing said press element, in a first step said
relief or at least a portion of this relief is formed, and in a second, subsequent
step a surface structure determining a different gloss degree is realized at the surface
of, at the one hand, at least a number of said higher-situated zones and, on the other
hand, at least a number of said lower-situated zones.
[0008] By "determining the gloss degree", it is meant that by means of the respective zones,
corresponding zones of different gloss degree are formed at the decorative side of
the formed coated panel. Preferably, this relates to a difference in gloss degree
clearly manifesting itself as matte and glossy at the decorative side of the coated
panels. Preferably, a difference in gloss degree is obtained at the decorative side,
wherein the matte zones have a gloss degree of 10, or still better less than 10, whereas
the glossy zones have a gloss degree of more than 10, or still better of more than
20. Independently from the respective absolute gloss degree, at the decorative side
of the coated panel preferably a difference between the glossy and matte zones of
at least 10 is obtained, all this measured according to DIN 67530.
[0009] When the gloss degree on the press plate is measured, a glossy zone preferably corresponds
to a gloss degree of more than 40, and still better of more than 100, and a matte
zone to a gloss degree of less than 40, also measured according to DIN 67530.
[0010] It is clear that higher-situated zones on the press element result in deeper-situated
impressed portions of the obtained coated panel. Due to the fact that zones, according
to their level on the press element, or on the decorative side of the floor panel,
can be provided with another gloss degree, it is possible to achieve in a smooth manner
special effects at the decorative side of the manufactured coated panels, such as
special depth effects. Also, at the decorative side of such coated panel, better imitations
of certain natural products, such as of certain wood species, can be realized.
[0011] It is noted that said surface structure determining the gloss degree can be obtained
by realizing a microstructure, such as a roughness, at the respective surface of the
pressing plate and/or by forming a cover layer at the respective surface, such as
a layer of chromium.
[0012] Preferably, for said press element a plate is applied which is substantially flat
at the pressing side, wherein this plate is provided with protruding portions and
these protruding portions form said higher-situated zones and the substantially flat
areas lying in between form said lower-situated zones. It is noted that such protruding
portions preferably protrude not more than 1 mm and still better not more than 0.5
mm above the lower-situated zones. It is clear that also in the lower-situated zones,
level differences may be present, which then preferably are not more than 0.2 mm and
still better are not more than 0.07 mm.
[0013] Preferably, for the material of the press element of the invention metal, such as
a steel alloy or a copper alloy, is applied.
[0014] In the step of forming the coated panels, preferably use is made of the also above-described
DPL technique.
[0015] Preferably, the higher-situated zones of the press element show a gloss degree-determining
surface structure over the majority of their surface, which differs from the gloss
degree-determining surface structure of the majority of the lower-situated zones,
wherein the higher-situated zones preferably show a higher gloss degree than the lower-situated
zones. In such manner, it is possible to achieve at the decorative side of the coated
panel effects in a particularly convincingly manner, wherein impressed portions are
present as matte or glossy accents in the respectively predominantly glossy or matte
surface.
[0016] In a particularly preferred embodiment, the press element is provided with a relief
having the form of a wood structure, wherein said higher-situated zones comprise at
least wood pores of this wood structure and wherein then preferably substantially
only the wood pores are provided with the surface structure determining a different
gloss degree.
[0017] It is clear that the present invention is not restricted to manufacturing coated
panels representing a wood structure or wood motif. The present invention can also
be applied when the printed decor and the pertaining structure relate to a stone motif,
a stone structure, respectively, or if this concerns fantasy motifs, fantasy structures,
respectively.
[0018] In general, the surface of the higher-situated zones, which is provided with a different
gloss degree, preferably shows a higher gloss degree in respect to the surface of
the lower-situated zones. In such manner, impressed portions can be emphasized most
efficiently and subtle.
[0019] Moreover, the present invention is particularly interesting when said decor represents
a motif and when said relief and the motif of said decor are in mutual correspondence,
such that said impressed portions in the decorative side follow said motif at least
partially or coincide therewith at least partially. Here, this relates to impressed
portions provided, so to say, "in register" with the underlying motif of the, preferably
printed, pattern. This embodiment allows obtaining particularly convincing imitations
of, for example, solid wood.
[0020] Preferably, in the step of making said press element, on the one hand, at least a
first series of treatments is performed on the press element, wherein at least said
higher-situated zones are formed, and, on the other hand, at least a second series
of treatments is performed on the press element, wherein substantially either only
the higher-situated zones or only the lower-situated zones of this press element are
subjected to this second series of treatments. According to this method, the step
of making the press element can be performed smoothly and efficiently. Preferably,
when performing at least a portion of said second series of treatments either the
lower-situated zones or the higher-situated zones, respectively, of the already formed
relief are physically or chemically shielded from the treatment concerned. Hereby,
the second series of treatments can be performed selectively on the respective zones
in a simpler manner.
[0021] Said shielding can be achieved by means of a material layer provided on the respective
zone, which material layer is resistant to the respective treatment and which, after
performing this second series of treatments, either is removed or not. So, for example,
a lacquer may be used which is resistant against etching, whether or not electrochemically,
with certain agents. Hereby, this may relate to a UV or air-drying lacquer. The application
of such material layer may take place by means of any application technique, for example,
by means of a printing technique, a spreading technique or an application technique
by means of a device comprising one or more rollers, wherein the rollers concerned
may or may not be engraved and may or may not be compressible, such as it is the case
with a rubber roller. Said application technique may or may not be digitally controlled.
In particular, a technique may be applied which as such is known from WO 2007/147376.
[0022] For said first series of treatments, one or a combination of two or more of the following
treatments can be applied:
- a chemical or electrochemical etching treatment;
- a machining treatment by means of a mechanical tool;
- a machining treatment from the list of spark erosion, laser treatment and ultrasonic
treatment;
- a mechanical or galvanic polishing treatment;
- a treatment wherein a covering layer is applied;
- a chromium plating;
- a treatment wherein a matte microstructure is obtained on the relief.
[0023] For said second series of treatments, one or a combination of two or more of the
following treatments can be applied:
- a chemical or electrochemical etching treatment;
- a mechanical or galvanic polishing treatment;
- a treatment wherein a covering layer is applied;
- a hard chromium plating;
- a treatment wherein a glossy microstructure is obtained on said protruding portions;
- a treatment wherein material is applied selectively.
[0024] In the following, several particular combinations of the above possibilities are
discussed specifically.
[0025] According to a first possibility, in a first series of treatments the pressing plate
or another press element can be provided with a structure in any manner, for example,
by etching, after which the lower-situated zones of the pressing plate are shielded
and the higher-situated zones are polished by means of the technique of electro-polishing.
[0026] According to a second possibility, in a first series of treatments the pressing plate
or any other press element can be substantially entirely or entirely chromium-plated
matte or sandblasted, after which the pressing plate is selectively chromium-plated
at the height of the higher-situated zones. This can be achieved, for example, by
shielding, in the chromium bath, the lower-situated zones by means of a resistant
material layer.
[0027] According to a third possibility, in a first series of treatments, the pressing plate
or any other press element can be chromium-plated substantially entirely or entirely
glossy, after which the pressing plate selectively is chromium-plated matte or is
sandblasted at the height of the lower-situated zones. This can be achieved, for example,
by shielding the higher-situated zones by means of a resistant material layer.
[0028] Generally, the higher-situated zones of a press element with the characteristics
of the present invention preferably cover less than 20% and still better less than
10% of the surface of the entire pressing side of the press element concerned.
[0029] The invention also relates to a coated panel, which is obtained by a method according
to the invention.
[0030] Preferably, the impressed portions of such coated panel substantially show another
gloss degree than the remaining, preferably substantially flat portions of the decorative
side. Herein, the impressed portions can be made glossier or more matte.
[0031] With the intention of better showing the characteristics of the invention, hereafter,
as an example without any limitative character, several preferred embodiments are
described, with reference to the accompanying drawings, wherein:
Figure 1 represents a cross-section through the top layer of a coated panel obtained
by means of the method of the present invention;
Figure 2 schematically represents a step of the method of the present invention;
Figure 3 schematically represents another step of the method of the present invention
according to a view on the area indicated by F3 in figure 2; and
Figure 4 , in a similar view, represents a variant.
[0032] Figure 1 represents a coated panel 1, which can be obtained according to the invention.
Such panel comprises at least a substrate 2, a decor 3 and a top layer 4 on the basis
of synthetic material 5. Herein, the decor 3 more particularly relates to a print,
which is provided on a material sheet 6 and which, provided with synthetic material
5, is included in the top layer 3 as a so-called decor layer 7. Above this decor layer,
a protective layer 8 on the basis of synthetic material is provided, which in this
case also comprises a material sheet 7 provided with synthetic material or resin.
[0033] It is noted that such top layer also can comprise hard particles situated at least
above the printed decor, however, such hard particles are not represented here. This
may relate, for example, to aluminum oxide particles with an average grain size between
0.1 and 200 µm.
[0034] According to the invention, the coated panel 1 has impressed portions 10 at the decorative
side 9, in this case, this relates at least to impressed portions 10 for imitating
wood pores. In the represented example, the impressed portions 10 have a higher gloss
degree than the remaining portions 11 of the decorative side 9.
[0035] Figure 2 schematically represents the step S1 of the method of the invention wherein
the coated panel 1 is formed. Herein, the coated panel 1 of figure 1 is formed by
means of the also above-mentioned DPL technique. To this aim, at least the substrate
2 or a board comprising this substrate 2, the decorative layer 7 and the protective
layer 8 are brought into a press device 12, where they are consolidated by means of
a press element 13. In the represented case, the stack also comprises a so-called
backing layer or balancing layer 14 at the underside, which layer is intended for
being provided at the underside of the substrate 2 and in this case also substantially
consists of a material sheet 6, such as a paper sheet, provided with synthetic material
5 or resin.
[0036] Figure 2 clearly shows that the press element 13 is provided with a relief 16 at
its surface or pressing side 15, said relief showing higher-situated zones 17 and
lower-situated zones 18. In the step of forming the coated panels 1, said press element
13 is applied for forming, by means of the relief 16, the already mentioned impressed
portions 10 and the structure of the remaining portions 11 in the decorative side
9 of the coated panels, or more particularly in the decorative sides of boards from
which such coated panels can be obtained.
[0037] The particularity of the present invention is represented, amongst others, in figure
3. This figure 3 clearly represents a part of the step S0 for producing the press
element 13. Herein, the press element 13 is being provided with a relief 16 at its
surface or pressing side 15. The press element or pressing plate 13 represented at
the top in figure 3 is provided with the relief 16 in a first step, or at least is
provided with at least a portion of this relief 16. The relief 16 realized in this
first step shows the same or at least virtually the same gloss degree-determining
surface structure at the surface of the higher-situated zones 17 as well as at the
surface of the lower-situated zones 18. Here, this relates to a relatively matte surface
structure, which is represented schematically by means of the rough surface. Such
relief 16 and surface structure can be achieved, for example, by means of an etching
technique or a milling technique or a combination of both.
[0038] In a subsequent step, indicated here by arrow 19, a mutually differing gloss degree-determining
surface structure is realized at the surface of, on the one hand, at least a number
of the higher-situated zones 17 and, on the other hand, at least a number of the lower-situated
zones 18. To this aim, as represented, the lower-situated zones 18 are shielded with
a material layer 20, such that they are not or less affected by the treatment or treatments
performed in said subsequent step and thus substantially retain their surface structure
realized in said first step. For example, the treatment concerned may relate at least
to a treatment in which the technique of electro-polishing is applied, by which a
higher gloss degree is achieved at the location of the higher-situated zones 18.
[0039] Figure 4 shows another variant, wherein in said subsequent step a covering layer
21 is provided on said higher-situated zones 17 or at least on a number thereof, whereas
the lower-situated zones 16 are left undisturbed by the presence of said material
layer 20. Said covering layer may relate, for example, to a chromium layer, preferably
of the type that can be obtained by means of the technique of hard chromium plating,
by which a higher gloss degree can be achieved at the higher-situated zones 18.
[0040] It is clear that said material layer 20 preferably is removed after the respective
zones 17-18 have obtained their final, gloss degree-determining surface structure.
[0041] It is noted that the technique of the present invention preferably is applied for
manufacturing floor panels, which preferably are of the type which can be installed
free from glue. Glue-free installable floor panels are known as such, for example,
from WO 97/47834. However, the respective technique can also be applied for manufacturing
furniture panels, wall panels, ceiling panels and the like.
[0042] According to the invention, any material can be applied as a substrate. So, for example,
a wood-based board material, such as chipboard, MDF or HDF (Medium Density Fiberboard
or High Density Fiberboard) or plywood, can be applied.
[0043] Further, it is noted that the impressed portions, or at least the majority thereof,
which according to the invention are provided in the decorative side of the coated
panels, and thus in particular when impressed portions for imitating wood pores are
concerned, preferably are situated entirely above the printed decor, or in other words
do not penetrate into this printed decor or do not penetrate through this printed
decor. Namely, the impressed portions preferably remain restricted to the layer of
synthetic material provided above the printed decor, or still better remain restricted
to said protective layer.
[0044] As represented by means of figure 2, the coated panel obtained by means of the invention
preferably also comprises a backing layer.
[0045] Preferably, the consolidation in the press device, as in the case of figure 2, is
obtained substantially or exclusively by means of said synthetic material or the resin.
Such resin may be, for example, a thermo-hardening resin, such as melamine formaldehyde
resin.
[0046] It is also noted that the invention preferably is applied for manufacturing coated
panels, such as floor panels, wherein hard particles are present in the top layer,
such as particles of aluminum oxide or silicon carbide.
[0047] It is clear that the embodiments of the present invention represented in the figures
represent still further preferred embodiments mentioned in the introduction. For example,
it is clear that the press element 13 applied in the examples relates to a plate,
which is substantially flat at the pressing side 15, which plate is provided with
protruding portions then forming said higher-situated zones 17, whereas the substantially
flat zones lying in between form said lower-situated zones 18. Moreover, the higher-situated
zones 17 show the respective, gloss degree-determining surface structure over the
majority of their surface.
[0048] The present invention is in no way limited to the above-described embodiments, on
the contrary may such methods and coated panels be realized according to various variants,
without leaving the scope of the present invention.
1. Method for manufacturing coated panels, wherein these panels (1) are of the type comprising
at least a substrate (2), a decor (3) and a top layer (4) on the basis of synthetic
material (5), wherein the method comprises at least the following steps:
- producing a press element (13), wherein this press element (13) is provided with
a relief (16) at its surface or pressing side (15), said relief (16) comprising higher-situated
zones (17) and lower-situated zones (18);
- forming the aforementioned coated panels (1), wherein said press element (13) is
applied for forming impressed portions (10) in the decorative side (9) of the coated
panels (1) by means of said relief (16), and more particularly in the decorative side
(9) of boards, from which then such coated panels (1) can be obtained;
with the characteristic that, when producing said press element (13), in a first step
said relief (16) or at least a portion of this relief (16) is formed, and in a second,
subsequent step (19) a surface structure determining a mutually different gloss degree
is realized at the surface of, at the one hand, at least a number of said higher-situated
zones (17) and, on the other hand, at least a number of said lower-situated zones
(18).
2. Method according to claim 1, characterized in that for said press element (13) a plate is applied, which is substantially flat at the
pressing side (15), wherein this plate is provided with protruding portions and these
protruding portions form said higher-situated zones (17) and the substantially flat
zones lying in between form said lower-situated zones (18).
3. Method according to claim 1 or 2, characterized in that said higher-situated zones (17) show a gloss degree-determining surface structure
over the majority of their surface, which surface structure differs from the gloss
degree-determining surface structure of the majority of the lower-situated zones (17),
wherein the higher-situated zones (17) preferably show a higher gloss degree than
the lower-situated zones (18).
4. Method according to any of the preceding claims, characterized in that the press element (13) is provided with a relief (16) having the form of a wood structure,
wherein said higher-situated zones (17) comprise at least wood pores of this wood
structure and wherein then preferably substantially only the wood pores are provided
with the different gloss degree-determining surface structure.
5. Method according to any of the preceding claims, characterized in that the surface of the higher-situated zones (17), which is provided with a different
gloss degree in respect to the surface of the lower-situated zones (18), has a higher
gloss degree.
6. Method according to any of the preceding claims, characterized in that said decor (3) represents a motif and that said relief (16) and the motif of said
decor (3) are in accordance with each other, such that said impressed portions (10)
in the decorative side (9) follow said motif at least partially or at least partially
coincide therewith.
7. Method according to any of the preceding claims, characterized in that in the step of producing said press element (13), on the one hand, at least a first
series of treatments is performed on the press element (13), wherein at least said
higher-situated zones (17) are formed, and, on the other hand, at least a second series
of treatments is performed on the press element (13), wherein substantially either
only the higher-situated zones (17) or only the lower-situated zones (18) of this
press element (13) are subjected to this second series of treatments.
8. Method according to claim 7, characterized in that when performing at least a part of said second series of treatments, either the lower-situated
zones (18) or the higher-situated zones (17), respectively, of the already formed
relief are physically or chemically shielded from the treatment concerned.
9. Method according to claim 8, characterized in that said shielding is achieved by means of a material layer (20) provided on the respective
zone (17-18), which material layer is resistant to the respective treatment and which,
after performing this second series of treatments, either is removed or not.
10. Method according to any of the claims 7 to 9,
characterized in that said first series of treatments comprises one or a combination of two or more of
the following treatments:
- a chemical or electrochemical etching treatment;
- a machining treatment by means of a mechanical tool;
- a machining treatment from the list of spark erosion, laser treatment and ultrasonic
treatment;
- a mechanical or galvanic polishing treatment;
- a treatment wherein a covering layer is applied;
- a chromium plating;
- a treatment wherein a matte microstructure is obtained on the relief.
11. Method according to any of the claims 7 to 10,
characterized in that said second series of treatments comprises one or a combination of two or more of
the following treatments:
- a chemical or electrochemical etching treatment;
- a mechanical or galvanic polishing treatment;
- a treatment wherein a covering layer is applied;
- a hard chromium plating;
- a treatment wherein a glossy microstructure is obtained on said protruding portions.
12. Coated panel, characterized in that it is obtained by a method according to any of the preceding claims.
13. Coated panel according to claim 12, characterized in that said impressed portions (10) substantially show another gloss degree than the remaining
portions (11) of the decorative side (9).
14. Coated panel according to claim 12 or 13, wherein the impressed portions (10) show
a higher gloss than said remaining portions (11).
15. Coated panel according to claim 12 or 13, wherein the impressed portions (10) show
a lower gloss degree than said remaining portions (11).