Patent Description:
In recent years, printed building panels have gained increasing success. These types of decorative floor and wall panels usually comprise a thermoplastic substrate and a protective layer. The thermoplastic material is often polyvinyl chloride. The substrate is printed with a pattern resembling natural stone, wood, ceramics etc. The pattern is often printed by rotogravure printing or direct printing.

Recently digital printing has offered new possibilities to the flooring industry to customize decorative patterns for floor and wall applications and to print small quantities of substrates. By digital printing is conventionally meant printing by means of non-contact printing, for example using a Drop-on-Demand (DOD) technique. A drop of ink is placed with great accuracy on a surface. Examples of DOD techniques are piezoelectric DOD inkjet and thermal DOD inkjet. In a piezoelectric DOD inkjet printer, the piezoelectric material changes shape when a voltage is applied. The change of shape of the piezoelectric material generates a pressure pulse in the fluid, thereby ejecting a droplet of ink from the nozzle. In a thermal DOD inkjet printer, ink drops are ejected by forming an ink vapor bubble by heating the ink.

Digital printers use one of two methods to print: single-pass and multi-pass. In the first case, the surface to be printed is fed in a single pass over four print heads, representing the four primary colors (cyan, magenta, yellow and black), which results in faster printing. In multi-pass, the same surface travels a longer path since it goes through four successive passes (one per color). Multi-pass reduces the cost of the printer since there's only one drum for all the primary colors, whereas with single-pass, there has to be one drum per primary color, but of course printing times are at least four times as long.

Different kind of inks may be used, such as UV curable inks, solvent based inks and aqueous inks (also called waterborne or water based inks). When printing on a thermoplastic substrates such as a substrate adapted to from decorative surface coverings, printing is facilitated by using UV curable inks or solvent based inks compared to aqueous inks.

Inks based on organic solvents adhere directly to a plastic film and dry quickly on the plastic film surface.

There are also known organic inks based on relatively high-boiling water-free solvents. These solvents are non-explosive, but they dry only slowly. Disadvantages of these organic inks is that when dots of ink are applied they easily run, because drying is slow, and this militates against sharp profiles and the clean printing of different colors adjacent to one another.

<CIT> discloses a method of using a plastic film for printing with organic ink in an inkjet process, comprising ink jet printing directly on the plastic film with the organic ink, wherein the plastic is selected from polyvinyl chloride, polyethylene, polypropylene, polystyrene, polycarbonate, poly(meth)acrylate or mixtures of these, and the plastic film further comprises from <NUM> to <NUM>% of cellulose esters, where the esters contain acetyl, propionyl, or butyryl groups. <CIT> discloses an impregnated product that can be used as a base or carrier sheet in the manufacture of decorative vinyl-surfaced felt base floor coverings, wall coverings, and the like. The saturated base sheet of this invention is given a ground coat of a vinyl chloride organosol resin containing titanium dioxide pigment. The ground-coated sheet is then rotogravure printed with inks having aromatic and ketone solvents.

Printing with an aqueous ink on a thermoplastic substrate has proved to be difficult. A drop of an aqueous ink does not stay but tends to bleed on the thermoplastic surface, resulting in a print of low quality. However, due to environmental reasons, it is favorable to replace solvent based inks.

In order to provide an improved print on a thermoplastic material, obtained from digital printing of an aqueous pigment ink, <CIT> discloses an aqueous solution comprising a salt, preferably at least one metal salt, for being used as a primer before the digital printing step.

The metal salt may be a monovalent metal salt, for example comprising a monovalent ion such as Na+. The metal salt may be a polyvalent metal salt. Preferably, the polyvalent metal salt comprises divalent ions such as Ca<NUM>+, Cu<NUM>+, Ni<NUM>+, Mg<NUM>+, Zn<NUM>+, or Ba<NUM>+, or trivalent ions such as Al<NUM>+ or Fe<NUM>+. The metal salt may for example be sodium chloride or calcium chloride. The salt may also be a non-metal salt such as ammonium chloride.

The present invention aims to provide printed decorative floor and wall coverings comprising high quality images obtained from printing (including digital printing) of ink compositions directly on the thermoplastic surface.

A further aim of the present invention is to provide a method for producing said printed decorative floor and wall coverings.

The present invention discloses a printed decorative floor or wall covering comprising one or more polymer layers and comprising a decorative design print obtained by aqueous ink composition printing directly on at least one surface of said one or more polymer layers, said one or more polymer layers comprising a blend of, in relative proportions:.

the printed decorative floor or wall covering further comprising a cross-linked topcoat.

Preferred embodiments of the present invention disclose one or more of the following features:.

The present invention further discloses a process for the preparation of the printed decorative floor or wall covering, comprising the steps of:.

Preferred embodiments of the process for the preparation of said printed decorative floor or wall covering disclose one or more of the following features:.

The present invention provides decorative floor and wall coverings comprising high quality prints, obtained from printing of ink compositions directly on at least one surface of at least one polymer layer, said at least one polymer layer preferably being part of at least two polymer layers constituting said final floor or wall covering, said polymer layers comprising polyvinyl chloride and/or polyvinyl chloride copolymer(s).

It has been surprisingly found that the partial substitution of polyvinyl chloride and/or polyvinyl chloride copolymer(s) by one or more particular polymer(s), while reducing the amount of plasticizer(s), result in polymer layers with modified surface properties, obtainable from conventional processing conditions and enabling said high quality prints. With high quality prints the present invention means prints having a perfect delineation, sharpness, color strength and adherence to the polymer layer.

The present invention provides printed decorative floor or wall coverings comprising one or more polymer layers, said one or more polymer layers comprising a first polymer selected from the group consisting of polyvinyl chloride, polyvinyl chloride copolymer and mixtures thereof in a blend with a second polymer selected from the group consisting of:.

The polyvinyl chloride copolymers are copolymers of vinyl chloride and other ethylenically unsaturated monomers including for example vinyl alkanoates such as vinyl acetate, vinyl propionate and the like; vinyl halides such as vinylidene bromide, vinylidene chloride and the like; unsaturated hydrocarbons such as ethylene, propylene, isobutylene and the like; allyl compounds such as allyl acetate, allyl chloride and the like.

The polyvinyl chloride copolymer comprises at least <NUM>% by weight, preferably at least <NUM>% by weight, more preferably at least <NUM>% by weight, most preferably at least <NUM>% by weight of vinyl chloride.

The first polymer for being used in the polymer layers according to the present invention, is characterized by a Fikentscher K-value according to DIN <NUM> (<NUM>/<NUM> cyclohexanone @ <NUM>) comprised between <NUM> and <NUM>, preferably between <NUM> and <NUM>, more preferably between <NUM> and <NUM>.

The K-value, being derived from the solution viscosity, correlates intrinsic viscosity and average degree of polymerization. Typically the higher the K value the better the mechanical properties but the lower the flowability.

While for conventional PVC-based floor and wall coverings a K value comprised between <NUM> and <NUM> is preferred, it has been found that processing, in particular calendering, is improved for the polymer blend according to the present invention, wherein a first polymer with a K value less than <NUM>, preferably less than <NUM> is used.

The first polymer for being used in the at least two polymer layers according to the present invention, preferably is characterized by a number average molecular weight comprised between <NUM> and <NUM>/mole, more preferably between <NUM> and <NUM>/mole, most preferably between <NUM> and <NUM>/mole.

The homo- or copolymers i. ) comprising one or more vinyl alkanoate(s) are polymers comprising one or more vinyl alkanoate monomer(s), defined by the general formula RCOOCH=CH<NUM>, wherein R is an alkyl radical containing from <NUM> to <NUM> carbon atoms, and are preferably selected from the group consisting of vinyl formate, vinyl acetate, vinyl propionate, vinyl butyrate, vinyl octanoate and vinyl stearate.

Preferably the vinyl alkanoate copolymers comprise at least <NUM>% by weight, more preferably at least <NUM>% by weight, most preferably at least <NUM>% by weight or even at least <NUM>% by weight of vinyl acetate. Preferably the vinyl alkanoate polymer is polyvinyl acetate.

The copolymers ii. ) comprising one or more alkenes and one or more vinyl alkanoate(s) are copolymers, wherein the one or more alkenes are defined by the general formula R<NUM>R<NUM>C=CR<NUM>R<NUM>, wherein R<NUM>, R<NUM>, R<NUM> and R<NUM> independently is a hydrogen or an alkyl radical containing from <NUM> to <NUM> carbon atoms, and are preferably selected from the group consisting of ethene, propene, <NUM>-butene, <NUM>-pentene, <NUM>-hexene, <NUM>-methyl-<NUM>-butene, <NUM>,<NUM>-dimethyl-<NUM>-pentene; and wherein the one or more vinyl alkanoate monomer(s) are defined as in paragraph <NUM>.

Preferably the alkene/vinyl alkanoate copolymer ii. ) comprises at least <NUM>% by weight, more preferably at least <NUM>% by weight, most preferably at least <NUM>% by weight or even at least <NUM>% by weight of one or more vinyl alkanoate(s) and <NUM>% or less, preferably <NUM>% or less, more preferably <NUM>% or less , most preferably <NUM>% or less of one or more <NUM>-alkene(s).

Preferably the alkene/vinyl alkanoate copolymer is an ethylene/vinyl acetate copolymer comprising at least <NUM>% by weight, preferably at least <NUM>% by weight, more preferably at least <NUM>% by weight, most preferably at least <NUM>% by weight of vinyl acetate.

The alkyl (meth)acrylate copolymers iii. ) comprise alkyl (meth)acrylates with <NUM> to <NUM> carbon atoms in the alkyl group; said alkyl (meth)acrylates are selected from the group consisting of methyl (meth)acrylate, ethyl (meth)acrylate, n-propyl (meth)acrylate, n-butyl (meth)acrylate, i-butyl (meth)acrylate, n-hexyl (meth)acrylate, and <NUM>-ethylhexyl (meth)acrylate.

The alkyl (meth)acrylate copolymers may be random copolymers.

Preferably, the alkyl (meth)acrylate copolymer iii. ) used in the present invention is a block copolymer, comprising from <NUM> to <NUM>% by weight, preferably from <NUM> to <NUM>% by weight of one or more block(s) comprising alkyl methacrylate monomers and from <NUM> to <NUM>% by weight, preferably from <NUM> to <NUM>% by weight of one or more blocks comprising alkyl acrylate monomers.

Preferably the glass transition temperature (measured by Differential Scanning Calorimetry, according to ASTM D3418 with a heating gradient of <NUM> per minute) of the alkyl methacrylate comprising blocks is comprised between <NUM> and <NUM>, more preferably between <NUM> and <NUM> and most preferably between <NUM> and <NUM>. The glass transition temperature of the alkyl acrylate comprising blocks is comprised between -<NUM> and -<NUM>, preferably between -<NUM> and -<NUM> and more preferably between -<NUM> and -<NUM>.

Preferably the alkyl (meth)acrylate copolymer is a di-block copolymer comprising a block comprising alkyl acrylate monomers and a block comprising alkyl methacrylate monomers such as for example a di-block copolymer comprising a block comprising n-butyl acrylate monomers and a block comprising methyl methacrylate monomers.

The alkyl (meth)acrylate copolymer more preferably is a tri-block copolymer comprising one block comprising alkyl acrylate monomers and two blocks comprising alkyl methacrylate monomers such as for example a tri-block copolymer comprising one block comprising n-butyl acrylate monomers and two blocks comprising methyl methacrylate monomers.

The one or more polymer layer(s) of the printed decorative floor or wall coverings according to the present invention comprise(s), per <NUM> parts by weight of the first polymer, between <NUM> and <NUM> parts by weight, preferably between <NUM> to <NUM> parts by weight, more preferably from <NUM> to <NUM> parts by weight, most preferably between <NUM> and <NUM> parts by weight or even between <NUM> and <NUM> parts by weight of second polymer.

The one or more polymer layer(s) of the printed decorative floor or wall coverings according to the present invention further may comprise, per <NUM> parts by weight of the first polymer, up to <NUM> parts by weight of one or more (co)polymers different from the second polymer such as for example a polyvinyl acetal, polyurethane, polyolefin among others.

It now has been found that polymer layers comprising the above blend, allow for high quality prints when the second polymer is characterized by a glass transition temperature or an average glass transition temperature when block copolymers are concerned, of <NUM> or less, preferably comprised between -<NUM> and <NUM>, more preferably between <NUM> and <NUM>, most preferably between <NUM> and <NUM> or even between <NUM> and <NUM>, measured by Differential Scanning Calorimetry (DSC), according to ASTM D3418 with a heating gradient of <NUM> per minute.

By average glass transition temperature the present invention means the arithmetic mean of the two transitions, corresponding to the glass transition temperature for each type of block.

In general, the polymer layers of conventional PVC floor and wall coverings comprise about equivalent amounts of PVC (<NUM> parts) and of plasticizer (<NUM> parts).

The inventors further have found that optimization of print quality and processing conditions results from reducing the amount of plasticizer, or even entirely omitting the plasticizer(s), said plasticizer(s) in general being a liquid, characterized by a molecular weight of <NUM>/mole or less, preferably of <NUM>/mole or less, more preferably of <NUM>/mole or less.

The one or more polymer layer(s) of the printed decorative floor or wall coverings according to the present invention comprise(s), per <NUM> parts by weight of first polymer, up to <NUM> parts by weight, preferably from <NUM> to <NUM> parts by weight, more preferably from <NUM> to <NUM> parts by weight, most preferably from <NUM> to <NUM> parts by weight and or even <NUM> to <NUM> parts by weight of one or more plasticizer(s) selected from the group consisting dialkyl esters of cyclohexane dicarboxylic acids, dialkyl esters of aliphatic dicarboxylic acids, alkyl esters of aromatic mono- di-, tri-, or tetra-carboxylic acids, lower alkyl citrates, epoxidized or otherwise derivatized vegetable oils, lower alkyl phosphates and lower alkyl sulfonates.

Dialkyl esters of cyclohexane dicarboxylic acids are preferably selected from the group consisting of the C<NUM>-C<NUM> di-alkyl esters of (methyl) <NUM>,<NUM>- and <NUM>,<NUM>-cyclohexane dicarboxylic acid.

Dialkyl esters of aliphatic dicarboxylic acids are preferably selected from the group consisting of the C<NUM>-C<NUM> di-alkyl esters of a C<NUM>-C<NUM> dicarboxylic acid.

Alkyl esters of aromatic di-, tri-, or tetra-carboxylic acids are preferably selected from the group consisting of the C<NUM>-C<NUM> di-alkyl of ortho-, iso and terephthalic acid, the benzyl C<NUM>-C<NUM> alkyl esters of ortho-, iso and terephthalic acid, the C<NUM>-C<NUM> tri-alkyl esters of trimellitic acid and the C<NUM>-C<NUM> tetra-alkyl esters of pyromellitic acid.

Alkyl esters of aromatic monocarboxylic acid are preferably selected from the group consisting of the C<NUM>-C<NUM> alkyl esters of benzoic acid and di- and tri- C<NUM>-C<NUM> alkylene glycol dibenzoate.

Lower alkyl citrates are preferably selected from the C<NUM>-C<NUM> tri-alkyl esters of (acetyl) citric acid.

Epoxidized or otherwise derivatized vegetable oils are preferably selected from the group consisting of epoxidized soybean oils, epoxidized linseed oil, epoxidized soy oil and epoxidized tall oil.

Lower alkyl phospates are preferably selected from the group consisting of the C<NUM>-C<NUM> mono-alkyl diphenyl esters of phosphoric acid, the phenyl C<NUM>-C<NUM> di-alkyl esters of phosphoric acid and the C<NUM>-C<NUM> tri-alkyl esters of phosphoric acid.

Alkyl sulfonates are preferably selected from the group consisting of the phenyl- and cresyl esters of C<NUM>-C<NUM> alkyl sulfonic acid.

Diisononyl cyclohexanoate, diisooctyladipate, dioctyladipate, dioctyl terephthalate, dibutyl terephthalate, di-(<NUM>-ethylhexyl) phthalate, diisononyl phthalate, diisodecyl phthalate, di-n-octyl phthalate, isononylbenzoate, diethylene glycol dibenzoate, acetyl tributyl citrate and epoxidized soyabean oil are preferred plasticizers within the context of the present invention.

The inventors thus have found that high print quality and optimized processing conditions are obtained for one or more polymer layer(s) prepared from melt-mixing and calendering a composition comprising a blend of:.

said one or more polymer layer(s) further being characterized by a Young's modulus, measured according to ISO <NUM>, comprised between <NUM> and <NUM> GPa, preferably between <NUM> and <NUM> GPa, more preferably between <NUM> and <NUM> GPa and most preferably between <NUM> and <NUM> GPa,.

In particular the high print quality is related to the Young's modulus of the one or more layer(s) comprising said print.

Besides the polymer blend, compositions according to the present invention may comprise further ingredients such as stabilizers, fillers and pigments or dyes.

Examples of fillers suitable for the composition of the present invention can be any conventional filler, especially those types traditionally used in floor or wall coverings.

The filler can be organic, inorganic, or a combination of both. Examples include, but are not limited to coal fly ash, carbonate salts such as magnesium carbonate, calcium carbonate and calcium-magnesium carbonate, barium sulfate, carbon black, metal oxides, inorganic material, natural material, alumina trihydrate, magnesium hydroxide, bauxite, talc, mica, dolomite, barite, kaolin, silica, post-consumer glass, or post-industrial glass, synthetic and natural fiber, or any combination thereof.

Preferably the filler comprises talc, mica, calcium carbonate, magnesium carbonate, barite, kaolin, bauxite, dolomite, silica, glass, or any combination thereof.

Examples of pigments and dyes suitable for the composition of the present invention are metallic oxides such as titanium dioxide, iron oxide, zinc oxide and the like, metal hydroxides, metal powders, sulphides, sulphates, carbonates, silicates, iron blues, organic reds, organic maroons and the like.

Examples of stabilizers are benzotriazole and benzophenone compounds and hindred amine light stabilizers to reduce the degradation by sunlight and stabilizers to provide stability during heat processing which are typically metal compounds, particularly lead salts, organotin compounds, barium, cadmium and zinc salts, calcium/zinc stabilisers, phosphites and sterically hindered phenols.

The ink compositions for being used in the present invention are dryable and/or curable and are solvent containing, water based or solventless inks comprising one or more polymer(s) and/or oligomers selected from the group consisting of polyolefins, poly(meth)acrylics, polyesters, polyamides, polyvinyl chloride, latex, polycarbonates, polyurethanes, polyethers, alkyd resins and mixtures thereof and one or more dyes and/or pigments. By curable ink composition, the present invention means cross-linking under the influence of heat or under the influence of actinic radiation.

The print is a decorative design print. The decorative design may be natural designs and patterns such as a wood pattern or stone pattern. The decorative design may also be a fantasy design or pattern or a photograph.

The print may be obtained from a conventional printing process, such as for example offset printing, flexography, rotogravure or a digital printing process, such as single-pass and multi-pass.

In the case of a digital printing process, the printer is preferably an inkjet printer. Preferably, the printer is a DOD (Drop on Demand) piezo-electric inkjet printer. In particular the printer is a single pass DOD (Drop on Demand) piezo-electric inkjet printer. A thermal DOD inkjet printer may also be used.

For the particular case of single-pass digital printing of water based inks the prior application of a primer, such as for example disclosed in <CIT>, is advisable. For the particular case of multi-pass digital printing, the use of radiation curable inks is advisable.

The printed decorative floor or wall covering preferably comprises a protecting layer, arranged on and bonded to the printed surface preferably through calendering. Said protecting layer preferably comprises the polymer blend of the present invention.

A topcoat layer, comprising cross-linked material, preferably obtained from cross-linking radiation curable coating compositions, is arranged on a protecting layer in order to improve the wear resistance and chemical resistance of the protecting layer.

The topcoat layer is preferably obtained from curing a radiation curable coating composition, said radiation curable composition comprising ethylenically unsaturated polyacrylate, polyester or polyurethane polymers and/or oligomers and optionally ethylenically unsaturated monomers. The radiation curable composition preferably comprises a radiation curable aqueous polyurethane dispersion.

Wear resistant particles such as aluminium oxide particles may be included in the cross-linked topcoat layer. The cross-linked topcoat layer is preferably transparent.

The printed decorative floor or wall coverings of the present invention may include a reinforced layer, comprising a carrier, such as a glass mat and/or non-woven.

The decorative floor and wall coverings of the present invention optionally are provided with a baking layer.

According to a second aspect of the present invention a method for producing said decorative floor or wall coverings is provided.

In one embodiment the method comprises providing a polymer layer by melt-mixing and calendering the composition of the present invention and printing an ink composition on the top-surface of said polymer layer to form a printed layer.

In a second embodiment at least two polymer layers, obtained from melt-mixing and calendering the composition of the present invention are contacted through calendering to form a layer stack. An ink composition is printed on the top-surface of said layer stack to form a printed layer stack.

In a third embodiment at least two polymer layers, obtained from melt-mixing and calendering the composition of the present invention are provided. An ink composition is printed on at least one surface of at least one polymer layer. In this embodiment printing may be performed on the upper surface or the lower surface of the at least one polymer layer;.

Of particular interest within this third embodiment is the application of two or more prints wherein printing is performed on:.

Same pattern or design may be printed. Alternatively, the print or design may be different. Finally the two or more prints may together form a specific design.

The at least two polymer layers, of which at least one polymer layer comprises at least one print, subsequently are contacted through calendaring to form a printed layer stack.

Printing is performed after cooling down the one or more polymer layer(s) or the layer stack to a temperature comprised between <NUM> and <NUM>, preferably between <NUM> and <NUM>.

The step of drying- and/or curing the pigment ink composition comprises applying heat and/or actinic radiation to the ink composition.

Heat may be applied in form of for instance medium and/or short infrared irradiation and/or heated air.

Actinic radiation may be applied by exposure to actinic radiation such as ultraviolet (UV) radiation with a wavelength of for instance <NUM>-<NUM> obtained from for example medium and high-pressure mercury vapour lamps, lasers, pulsed lamps (flashlight), halogen lamps, excimer emitters, LED lamps.

On the other hand actinic irradiation comprises bombardment with high-energy electron beams (EB) at for instance <NUM>-<NUM> keV.

A protecting layer is preferably contacted and bonded to the printed surface of the printed layer or the printed layer stack through calendering to form the decorative floor or wall covering.

A cross-linkable topcoat is applied on the top surface of the decorative floor or wall covering.

A radiation curable composition, preferably a radiation curable aqueous polyurethane dispersion is homogeneously applied on the top surface of the decorative floor or wall covering standing at a temperature comprised between <NUM> and <NUM>, preferably between <NUM> and <NUM>.

The radiation curable compositions of the present invention may be applied by any suitable coating process known to those of ordinary skill in the art, for example by direct gravure coating, reverse gravure coating, offset gravure coating, smooth roll coating, curtain coating, spray coating and combinations thereof. Direct gravure coating and smooth roll coating are preferred.

After evaporation of water, in a convection oven at about <NUM>, the decorative floor or wall covering comprising the polyurethane top-layer optionally is heated to a temperature comprised between <NUM> and <NUM>, and subsequently is mechanically embossed before cross-linking.

For the particular case where the radiation curable composition is not water based, such as for example a <NUM>% solids or a near <NUM>% solids composition said composition preferable is applied to the decorative floor or wall covering and cross-linked after the embossing step.

Mechanical embossing preferably is performed before irradiation of the uncured top-layer.

The embossed decorative floor or wall covering, comprising the uncured polyurethane coating, subsequently is cooled down to a temperature comprised between <NUM> and <NUM>, preferably between <NUM> and <NUM> and subjected to actinic radiation to form the decorative floor or wall covering.

Mechanical embossing is performed by pressing a texture into the decorative floor or wall covering comprising the polyurethane layer atop. Embossing is carried out at a pressure comprised between <NUM> and <NUM>. cm-<NUM> and surface temperature comprised between <NUM> and <NUM>, preferably between <NUM> and <NUM>.

The apparatus for mechanically embossing a substrate in general includes a cooled embossing roller and a backup roller operatively positioned within the embossing roller such that a nip is formed between the backup roller and the embossing roller whereby the substrate may pass through the nip and engage the embossing roller for imparting a mechanically embossed pattern. The apparatus further includes a profilometer capable of quantifying the mechanically embossed pattern as the substrate is being embossed.

In general the texture obtained from mechanical embossing is characterized by a depth comprised between about <NUM> to <NUM>, a width comprised between about <NUM> to <NUM>, a wall angle (angle relative to surface) comprised between about <NUM> to <NUM> degrees and a frequency of about <NUM> to <NUM> features per cm.

It has been observed that the bonding strength between two or more polymer layer(s) comprising the polymer blend of the present invention is comparable to the bonding strength between two or more layers of the current polyvinyl chloride floor or wall coverings.

Moreover the print does not reduce the bonding strength between the printed surface of one polymer layer and the printed or non-printed surface of an adjacent polymer layer.

Bonding between polymer layers, comprising the polymer blend of the present invention, is characterized peel strengths, according to ISO <NUM>:<NUM> (Resilient floor coverings - determination of peel resistance) in excess of 50N/<NUM>.

Furthermore, the print quality is not affected when contacting the printed surface with the printed or non-printed surface of an adjacent polymer layer.

The following illustrative examples are merely meant to exemplify the present invention and are not destined to limit or otherwise define the scope of the present invention.

A polymer layer is prepared from the composition as given in the table <NUM>.

A polymer layer of <NUM> thickness was prepared through melt-mixing in an extruder or internal and external mixer at a temperature of <NUM> and calendering in a roller mill at a temperature of <NUM>.

Two separate polymer layers of example <NUM> were bonded in a hot/cold-pressing step at <NUM> at approximately <NUM> bar pressure, followed by cooling down to <NUM>.

A peel strength, according to ISO <NUM>:<NUM> above 50N/<NUM> has been measured.

The polymer layer of example <NUM> was printed by means of a single pass digital printer with a water based ink. The print was dried during <NUM> seconds at <NUM> in an air ventilated oven. The printed image is fixated evenly over the surface of the polymer layer and a print result with good colour strength and resolution is achieved.

The printed polymer layer of example <NUM> was bonded to a transparent polymer layer with its printed surface in contact with the transparent polymer, the transparent polymer layer having the same composition as in table <NUM> except for pigment and filler.

Claim 1:
A printed decorative floor or wall covering comprising one or more polymer layers and comprising a decorative design print obtained by aqueous ink composition printing, preferably radiation-curable aqueous ink composition printing, directly on at least one surface of said one or more polymer layers, said one or more polymer layers comprising a blend of, in relative proportions:
- <NUM> parts by weight of a first polymer selected from the group consisting of polyvinyl chloride, copolymers of vinylchloride and other ethylenically unsaturated monomers, and mixtures thereof;
- from <NUM> to <NUM> parts by weight, preferably from <NUM> to <NUM> parts by weight, more preferably from <NUM> to <NUM> parts by weight of a second polymer selected from the group consisting of:
i.) homo- or copolymer(s) comprising one or more vinyl alkanoate(s) defined by the general formula RCOOCH=CH<NUM>, wherein R is an alkyl radical containing from <NUM> to <NUM> carbon atoms;
ii.) copolymers comprising one or more vinyl alkanoate(s), defined by the general formula RCOOCH=CH<NUM>, wherein R is an alkyl radical containing from <NUM> to <NUM> carbon atoms, and one or more alkene(s), defined by the general formula R<NUM>R<NUM>C=CR<NUM>R<NUM>, wherein R<NUM>, R<NUM>, R<NUM> and R<NUM> independently is a hydrogen or an alkyl radical containing from <NUM> to <NUM> carbon atoms;
iii.) copolymers of alkyl (meth)acrylate(s) with <NUM> to <NUM> carbon atom(s) in the alkyl group; and
iv.) mixtures of i.) and ii.); i.) and iii.); ii.) and iii.); and i.), ii.) and iii.).
the printed decorative flooring or wall covering further comprising a cross-linked topcoat.